Implement new Repository and Entity classes

This commit adds new Repository and Entity classes which are better
abstracted from the rest of the application. They dont know anymore
about configuration options or how to parse to HTML because this is
not the job for the ORM but for other parts of the application.

The previous commits were a preparation for this big change.

An entity now represents just a single record from a specific table
of the database – nothing more. The repositories job is it to fetch
or update records of the database and instantiate the entities.

Another problem that was solved is the high amount of database queries
that was needed before. For example, on the blogs home page first were
all 10 latest post IDs fetched from the database and then another query
was executed with "WHERE id = :id" for *each* single post?! ...

This problem is solved with the new repository classes; they now use a
single query to fetch and build the entities of the 10 latest posts.

This change also solves the problem with database queries spread across
the application and limits the exzessive use of try/catch blocks which
were used before. The new classes make the whole code much cleaner. :)

53 files changed, 1248 insertions, 1104 deletions

diff --git a/admin/auth.php b/admin/auth.php
index 9674563..03460ba 100644
--- a/admin/auth.php
+++ b/admin/auth.php
@@ -28,11 +28,10 @@ if(Application::isAuthenticated()) {
 # IF: Login action
 #===============================================================================
 if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'username', 'password')) {
-	try {
-		$User = User\Factory::buildByUsername(HTTP::POST('username'));
-		$password = $User->getAttribute()->get('password');
+	$UserRepository = Application::getRepository('User');
 
-		if(password_verify(HTTP::POST('password'), $password)) {
+	if($User = $UserRepository->findBy('username', HTTP::POST('username'))) {
+		if(password_verify(HTTP::POST('password'), $User->get('password'))) {
 			$_SESSION['auth'] = $User->getID();
 			HTTP::redirect(Application::getAdminURL());
 		}
@@ -40,7 +39,9 @@ if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'username', 'pa
 		else {
 			$messages[] = $Language->text('authentication_failure');
 		}
-	} catch(User\Exception $Exception){
+	}
+
+	else {
 		$fake_hash = '$2y$10$xpnwDU2HumOgGQhVpMOP9uataEF82YXizniFhSUhYjUiXF8aoDk0C';
 		$fake_pass = HTTP::POST('password');
 
diff --git a/admin/index.php b/admin/index.php
index b3508b5..c0383c4 100644
--- a/admin/index.php
+++ b/admin/index.php
@@ -11,42 +11,28 @@ define('AUTHENTICATION', TRUE);
 require '../core/application.php';
 
 #===============================================================================
-# Fetch last items and item count
+# Get repositories
 #===============================================================================
-$execute = 'SELECT id FROM %s ORDER BY time_insert DESC LIMIT 1';
-$LastPageStatement = $Database->query(sprintf($execute, Page\Attribute::TABLE));
-$LastPostStatement = $Database->query(sprintf($execute, Post\Attribute::TABLE));
-$LastUserStatement = $Database->query(sprintf($execute, User\Attribute::TABLE));
+$PageRepository = Application::getRepository('Page');
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
-$execute = 'SELECT COUNT(*) FROM %s';
-$PageCountStatement = $Database->query(sprintf($execute, Page\Attribute::TABLE));
-$PostCountStatement = $Database->query(sprintf($execute, Post\Attribute::TABLE));
-$UserCountStatement = $Database->query(sprintf($execute, User\Attribute::TABLE));
-
-try {
-	$LastPage = Page\Factory::build($LastPageStatement->fetchColumn());
-	$LastPageUser = User\Factory::build($LastPage->get('user'));
-
-	$PageItemTemplate = generatePageItemTemplate($LastPage, $LastPageUser);
+#===============================================================================
+# Last items
+#===============================================================================
+if($Page = $PageRepository->getLast()) {
+	$User = $UserRepository->find($Page->get('user'));
+	$PageItemTemplate = generatePageItemTemplate($Page, $User);
 }
 
-catch(Page\Exception $Exception){}
-catch(User\Exception $Exception){}
-
-try {
-	$LastPost = Post\Factory::build($LastPostStatement->fetchColumn());
-	$LastPostUser = User\Factory::build($LastPost->get('user'));
-
-	$PostItemTemplate = generatePostItemTemplate($LastPost, $LastPostUser);
+if($Post = $PostRepository->getLast()) {
+	$User = $UserRepository->find($Post->get('user'));
+	$PostItemTemplate = generatePostItemTemplate($Post, $User);
 }
 
-catch(Post\Exception $Exception){}
-catch(User\Exception $Exception){}
-
-try {
-	$LastUser = User\Factory::build($LastUserStatement->fetchColumn());
-	$UserItemTemplate = generateUserItemTemplate($LastUser);
-} catch(User\Exception $Exception){}
+if($User = $UserRepository->getLast()) {
+	$UserItemTemplate = generateUserItemTemplate($User);
+}
 
 #===============================================================================
 # Build document
@@ -55,14 +41,13 @@ $HomeTemplate = Template\Factory::build('home');
 $HomeTemplate->set('LAST', [
 	'PAGE' => $PageItemTemplate ?? FALSE,
 	'POST' => $PostItemTemplate ?? FALSE,
-	'USER' => $UserItemTemplate ?? FALSE,
-
+	'USER' => $UserItemTemplate ?? FALSE
 ]);
 
 $HomeTemplate->set('COUNT', [
-	'PAGE' => $PageCountStatement->fetchColumn(),
-	'POST' => $PostCountStatement->fetchColumn(),
-	'USER' => $UserCountStatement->fetchColumn(),
+	'PAGE' => $PageRepository->getCount(),
+	'POST' => $PostRepository->getCount(),
+	'USER' => $UserRepository->getCount()
 ]);
 
 $MainTemplate = Template\Factory::build('main');
diff --git a/admin/page/delete.php b/admin/page/delete.php
index e1c95f0..2465f62 100644
--- a/admin/page/delete.php
+++ b/admin/page/delete.php
@@ -11,46 +11,46 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: Page\Exception
+# Get repositories
 #===============================================================================
-try {
-	$Page = Page\Factory::build(HTTP::GET('id'));
-	$Attribute = $Page->getAttribute();
+$PageRepository = Application::getRepository('Page');
 
-	if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
-		try {
-			if($Attribute->delete($Database)) {
-				HTTP::redirect(Application::getAdminURL('page/'));
-			}
-		} catch(PDOException $Exception) {
-			$messages[] = $Exception->getMessage();
+#===============================================================================
+# Throw 404 error if page could not be found
+#===============================================================================
+if(!$Page = $PageRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
+
+#===============================================================================
+# Check for delete request
+#===============================================================================
+if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
+	try {
+		if($PageRepository->delete($Page)) {
+			HTTP::redirect(Application::getAdminURL('page/'));
 		}
+	} catch(PDOException $Exception) {
+		$messages[] = $Exception->getMessage();
 	}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('page/form');
-	$FormTemplate->set('HTML', parseEntityContent($Page));
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'DELETE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$DeleteTemplate = Template\Factory::build('page/delete');
-	$DeleteTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_page_delete'));
-	$MainTemplate->set('HTML', $DeleteTemplate);
-	echo $MainTemplate;
 }
 
 #===============================================================================
-# CATCH: Page\Exception
+# Build document
 #===============================================================================
-catch(Page\Exception $Exception) {
-	Application::error404();
-}
+$FormTemplate = Template\Factory::build('page/form');
+$FormTemplate->set('HTML', parseEntityContent($Page));
+$FormTemplate->set('FORM', [
+	'TYPE' => 'DELETE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($Page->getAll(), CASE_UPPER),
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$DeleteTemplate = Template\Factory::build('page/delete');
+$DeleteTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_page_delete'));
+$MainTemplate->set('HTML', $DeleteTemplate);
+echo $MainTemplate;
diff --git a/admin/page/index.php b/admin/page/index.php
index 7527afa..63839a9 100644
--- a/admin/page/index.php
+++ b/admin/page/index.php
@@ -11,12 +11,19 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$PageRepository = Application::getRepository('Page');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('ADMIN.PAGE.LIST_SIZE');
 $site_sort = Application::get('ADMIN.PAGE.LIST_SORT');
 
-$lastSite = ceil($Database->query(sprintf('SELECT COUNT(id) FROM %s', Page\Attribute::TABLE))->fetchColumn() / $site_size);
+$count = $PageRepository->getCount();
+$lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
 $currentSite = intval($currentSite);
@@ -26,19 +33,17 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 }
 
 #===============================================================================
-# Fetch page IDs from database
+# Get paginated page list
 #===============================================================================
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$pageIDs = $Database->query(sprintf($execSQL, Page\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+$pages = $PageRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($pageIDs as $pageID) {
-	try {
-		$Page = Page\Factory::build($pageID);
-		$User = User\Factory::build($Page->get('user'));
-		$templates[] = generatePageItemTemplate($Page, $User);
-	}
-	catch(Page\Exception $Exception){}
-	catch(User\Exception $Exception){}
+foreach($pages as $Page) {
+	$User = $UserRepository->find($Page->get('user'));
+	$templates[] = generatePageItemTemplate($Page, $User);
 }
 
 #===============================================================================
diff --git a/admin/page/insert.php b/admin/page/insert.php
index 1f9d391..6acfcfb 100644
--- a/admin/page/insert.php
+++ b/admin/page/insert.php
@@ -10,20 +10,32 @@ define('AUTHENTICATION', TRUE);
 #===============================================================================
 require '../../core/application.php';
 
-$Attribute = new Page\Attribute();
+#===============================================================================
+# Get repositories
+#===============================================================================
+$PageRepository = Application::getRepository('Page');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
+# Instantiate new Page entity
+#===============================================================================
+$Page = new Page\Entity;
 
+#===============================================================================
+# Check for insert request
+#===============================================================================
 if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'insert')) {
-	$Attribute->set('user', HTTP::POST('user'));
-	$Attribute->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
-	$Attribute->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
-	$Attribute->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
-	$Attribute->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-	$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-	$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+	$Page->set('user', HTTP::POST('user'));
+	$Page->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
+	$Page->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
+	$Page->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$Page->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$Page->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$Page->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
 	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
 		try {
-			if($Attribute->insert($Database)) {
+			if($PageRepository->insert($Page)) {
 				HTTP::redirect(Application::getAdminURL('page/'));
 			}
 		} catch(PDOException $Exception) {
@@ -36,12 +48,12 @@ if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_
 	}
 }
 
-$userIDs = $Database->query(sprintf('SELECT id FROM %s ORDER BY fullname ASC', User\Attribute::TABLE));
-
-foreach($userIDs->fetchAll($Database::FETCH_COLUMN) as $userID) {
-	$User = User\Factory::build($userID);
-	$userAttributes[] = [
-		'ID' => $User->get('id'),
+#===============================================================================
+# Generate user list
+#===============================================================================
+foreach($UserRepository->getAll([], 'fullname ASC') as $User) {
+	$userList[] = [
+		'ID' => $User->getID(),
 		'FULLNAME' => $User->get('fullname'),
 		'USERNAME' => $User->get('username'),
 	];
@@ -54,8 +66,8 @@ $FormTemplate = Template\Factory::build('page/form');
 $FormTemplate->set('FORM', [
 	'TYPE' => 'INSERT',
 	'INFO' => $messages ?? [],
-	'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-	'USER_LIST' => $userAttributes ??  [],
+	'DATA' => array_change_key_case($Page->getAll(), CASE_UPPER),
+	'USER_LIST' => $userList ??  [],
 	'TOKEN' => Application::getSecurityToken()
 ]);
 
diff --git a/admin/page/search.php b/admin/page/search.php
index 7d879f4..b74615f 100644
--- a/admin/page/search.php
+++ b/admin/page/search.php
@@ -11,20 +11,15 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# IF: Handle search request
+# Check for search request
 #===============================================================================
 if($search = HTTP::GET('q')) {
-	if($pageIDs = Page\Item::getSearchResultIDs($search, $Database)) {
-		foreach($pageIDs as $pageID) {
-			try {
-				$Page = Page\Factory::build($pageID);
-				$User = User\Factory::build($Page->get('user'));
+	$PageRepository = Application::getRepository('Page');
+	$UserRepository = Application::getRepository('User');
 
-				$templates[] = generatePageItemTemplate($Page, $User);
-			}
-			catch(Page\Exception $Exception){}
-			catch(User\Exception $Exception){}
-		}
+	foreach($PageRepository->search($search) as $Page) {
+		$User = $UserRepository->find($Page->get('user'));
+		$templates[] = generatePageItemTemplate($Page, $User);
 	}
 }
 
diff --git a/admin/page/update.php b/admin/page/update.php
index 5e54b03..2db0bc1 100644
--- a/admin/page/update.php
+++ b/admin/page/update.php
@@ -11,69 +11,70 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: Page\Exception
+# Get repositories
 #===============================================================================
-try {
-	$Page = Page\Factory::build(HTTP::GET('id'));
-	$Attribute = $Page->getAttribute();
+$PageRepository = Application::getRepository('Page');
+$UserRepository = Application::getRepository('User');
 
-	if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
-		$Attribute->set('user', HTTP::POST('user'));
-		$Attribute->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
-		$Attribute->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
-		$Attribute->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
-		$Attribute->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-		$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-		$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+#===============================================================================
+# Throw 404 error if page could not be found
+#===============================================================================
+if(!$Page = $PageRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
 
-		if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
-			try {
-				$Attribute->update($Database);
-			} catch(PDOException $Exception) {
-				$messages[] = $Exception->getMessage();
-			}
-		}
+#===============================================================================
+# Check for update request
+#===============================================================================
+if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
+	$Page->set('user', HTTP::POST('user'));
+	$Page->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
+	$Page->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
+	$Page->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$Page->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$Page->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$Page->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
-		else {
-			$messages[] = $Language->text('error_security_csrf');
+	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
+		try {
+			$PageRepository->update($Page);
+		} catch(PDOException $Exception) {
+			$messages[] = $Exception->getMessage();
 		}
 	}
 
-	$userIDs = $Database->query(sprintf('SELECT id FROM %s ORDER BY fullname ASC', User\Attribute::TABLE));
-
-	foreach($userIDs->fetchAll($Database::FETCH_COLUMN) as $userID) {
-		$User = User\Factory::build($userID);
-		$userAttributes[] = [
-			'ID' => $User->get('id'),
-			'FULLNAME' => $User->get('fullname'),
-			'USERNAME' => $User->get('username'),
-		];
+	else {
+		$messages[] = $Language->text('error_security_csrf');
 	}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('page/form');
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'UPDATE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-		'USER_LIST' => $userAttributes ??  [],
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$PageUpdateTemplate = Template\Factory::build('page/update');
-	$PageUpdateTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_page_update'));
-	$MainTemplate->set('HTML', $PageUpdateTemplate);
-	echo $MainTemplate;
 }
 
 #===============================================================================
-# CATCH: Page\Exception
+# Generate user list
 #===============================================================================
-catch(Page\Exception $Exception) {
-	Application::error404();
+foreach($UserRepository->getAll([], 'fullname ASC') as $User) {
+	$userList[] = [
+		'ID' => $User->getID(),
+		'FULLNAME' => $User->get('fullname'),
+		'USERNAME' => $User->get('username'),
+	];
 }
+
+#===============================================================================
+# Build document
+#===============================================================================
+$FormTemplate = Template\Factory::build('page/form');
+$FormTemplate->set('FORM', [
+	'TYPE' => 'UPDATE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($Page->getAll(), CASE_UPPER),
+	'USER_LIST' => $userList ??  [],
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$PageUpdateTemplate = Template\Factory::build('page/update');
+$PageUpdateTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_page_update'));
+$MainTemplate->set('HTML', $PageUpdateTemplate);
+echo $MainTemplate;
diff --git a/admin/post/delete.php b/admin/post/delete.php
index 94b60fc..1f398e1 100644
--- a/admin/post/delete.php
+++ b/admin/post/delete.php
@@ -11,46 +11,46 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: Post\Exception
+# Get repositories
 #===============================================================================
-try {
-	$Post = Post\Factory::build(HTTP::GET('id'));
-	$Attribute = $Post->getAttribute();
+$PostRepository = Application::getRepository('Post');
 
-	if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
-		try {
-			if($Attribute->delete($Database)) {
-				HTTP::redirect(Application::getAdminURL('post/'));
-			}
-		} catch(PDOException $Exception) {
-			$messages[] = $Exception->getMessage();
+#===============================================================================
+# Throw 404 error if post could not be found
+#===============================================================================
+if(!$Post = $PostRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
+
+#===============================================================================
+# Check for delete request
+#===============================================================================
+if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
+	try {
+		if($PostRepository->delete($Post)) {
+			HTTP::redirect(Application::getAdminURL('post/'));
 		}
+	} catch(PDOException $Exception) {
+		$messages[] = $Exception->getMessage();
 	}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('post/form');
-	$FormTemplate->set('HTML', parseEntityContent($Post));
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'DELETE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$DeleteTemplate = Template\Factory::build('post/delete');
-	$DeleteTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_post_delete'));
-	$MainTemplate->set('HTML', $DeleteTemplate);
-	echo $MainTemplate;
 }
 
 #===============================================================================
-# CATCH: Post\Exception
+# Build document
 #===============================================================================
-catch(Post\Exception $Exception) {
-	Application::error404();
-}
+$FormTemplate = Template\Factory::build('post/form');
+$FormTemplate->set('HTML', parseEntityContent($Post));
+$FormTemplate->set('FORM', [
+	'TYPE' => 'DELETE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($Post->getAll(), CASE_UPPER),
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$DeleteTemplate = Template\Factory::build('post/delete');
+$DeleteTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_post_delete'));
+$MainTemplate->set('HTML', $DeleteTemplate);
+echo $MainTemplate;
diff --git a/admin/post/index.php b/admin/post/index.php
index 8eedfbd..f6fcfb6 100644
--- a/admin/post/index.php
+++ b/admin/post/index.php
@@ -11,12 +11,19 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('ADMIN.POST.LIST_SIZE');
 $site_sort = Application::get('ADMIN.POST.LIST_SORT');
 
-$lastSite = ceil($Database->query(sprintf('SELECT COUNT(id) FROM %s', Post\Attribute::TABLE))->fetchColumn() / $site_size);
+$count = $PostRepository->getCount();
+$lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
 $currentSite = intval($currentSite);
@@ -26,19 +33,17 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 }
 
 #===============================================================================
-# Fetch post IDs from database
+# Get paginated post list
 #===============================================================================
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$postIDs = $Database->query(sprintf($execSQL, Post\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+$posts = $PostRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($postIDs as $postID) {
-	try {
-		$Post = Post\Factory::build($postID);
-		$User = User\Factory::build($Post->get('user'));
-		$templates[] = generatePostItemTemplate($Post, $User);
-	}
-	catch(Post\Exception $Exception){}
-	catch(User\Exception $Exception){}
+foreach($posts as $Post) {
+	$User = $UserRepository->find($Post->get('user'));
+	$templates[] = generatePostItemTemplate($Post, $User);
 }
 
 #===============================================================================
diff --git a/admin/post/insert.php b/admin/post/insert.php
index b4e2542..c640a39 100644
--- a/admin/post/insert.php
+++ b/admin/post/insert.php
@@ -10,20 +10,32 @@ define('AUTHENTICATION', TRUE);
 #===============================================================================
 require '../../core/application.php';
 
-$Attribute = new Post\Attribute();
+#===============================================================================
+# Get repositories
+#===============================================================================
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
+# Instantiate new Post entity
+#===============================================================================
+$Post = new Post\Entity;
 
+#===============================================================================
+# Check for insert request
+#===============================================================================
 if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'insert')) {
-	$Attribute->set('user', HTTP::POST('user'));
-	$Attribute->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
-	$Attribute->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
-	$Attribute->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
-	$Attribute->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-	$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-	$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+	$Post->set('user', HTTP::POST('user'));
+	$Post->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
+	$Post->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
+	$Post->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$Post->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$Post->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$Post->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
 	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
 		try {
-			if($Attribute->insert($Database)) {
+			if($PostRepository->insert($Post)) {
 				HTTP::redirect(Application::getAdminURL('post/'));
 			}
 		} catch(PDOException $Exception) {
@@ -36,12 +48,12 @@ if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_
 	}
 }
 
-$userIDs = $Database->query(sprintf('SELECT id FROM %s ORDER BY fullname ASC', User\Attribute::TABLE));
-
-foreach($userIDs->fetchAll($Database::FETCH_COLUMN) as $userID) {
-	$User = User\Factory::build($userID);
-	$userAttributes[] = [
-		'ID' => $User->get('id'),
+#===============================================================================
+# Generate user list
+#===============================================================================
+foreach($UserRepository->getAll([], 'fullname ASC') as $User) {
+	$userList[] = [
+		'ID' => $User->getID(),
 		'FULLNAME' => $User->get('fullname'),
 		'USERNAME' => $User->get('username'),
 	];
@@ -54,8 +66,8 @@ $FormTemplate = Template\Factory::build('post/form');
 $FormTemplate->set('FORM', [
 	'TYPE' => 'INSERT',
 	'INFO' => $messages ?? [],
-	'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-	'USER_LIST' => $userAttributes ??  [],
+	'DATA' => array_change_key_case($Post->getAll(), CASE_UPPER),
+	'USER_LIST' => $userList ??  [],
 	'TOKEN' => Application::getSecurityToken()
 ]);
 
diff --git a/admin/post/search.php b/admin/post/search.php
index 616359e..cfa2159 100644
--- a/admin/post/search.php
+++ b/admin/post/search.php
@@ -11,20 +11,15 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# IF: Handle search request
+# Check for search request
 #===============================================================================
 if($search = HTTP::GET('q')) {
-	if($postIDs = Post\Item::getSearchResultIDs($search, [NULL, NULL, NULL], $Database)) {
-		foreach($postIDs as $postID) {
-			try {
-				$Post = Post\Factory::build($postID);
-				$User = User\Factory::build($Post->get('user'));
+	$PostRepository = Application::getRepository('Post');
+	$UserRepository = Application::getRepository('User');
 
-				$templates[] = generatePostItemTemplate($Post, $User);
-			}
-			catch(Post\Exception $Exception){}
-			catch(User\Exception $Exception){}
-		}
+	foreach($PostRepository->search($search) as $Post) {
+		$User = $UserRepository->find($Post->get('user'));
+		$templates[] = generatePostItemTemplate($Post, $User);
 	}
 }
 
diff --git a/admin/post/update.php b/admin/post/update.php
index e22a54a..df0956b 100644
--- a/admin/post/update.php
+++ b/admin/post/update.php
@@ -11,69 +11,70 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: Post\Exception
+# Get repositories
 #===============================================================================
-try {
-	$Post = Post\Factory::build(HTTP::GET('id'));
-	$Attribute = $Post->getAttribute();
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
-	if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
-		$Attribute->set('user', HTTP::POST('user'));
-		$Attribute->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
-		$Attribute->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
-		$Attribute->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
-		$Attribute->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-		$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-		$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+#===============================================================================
+# Throw 404 error if post could not be found
+#===============================================================================
+if(!$Post = $PostRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
 
-		if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
-			try {
-				$Attribute->update($Database);
-			} catch(PDOException $Exception) {
-				$messages[] = $Exception->getMessage();
-			}
-		}
+#===============================================================================
+# Check for update request
+#===============================================================================
+if(HTTP::issetPOST('user', 'slug', 'name', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
+	$Post->set('user', HTTP::POST('user'));
+	$Post->set('slug', HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('name')));
+	$Post->set('name', HTTP::POST('name') ? HTTP::POST('name') : NULL);
+	$Post->set('body', HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$Post->set('argv', HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$Post->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$Post->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
-		else {
-			$messages[] = $Language->text('error_security_csrf');
+	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
+		try {
+			$PostRepository->update($Post);
+		} catch(PDOException $Exception) {
+			$messages[] = $Exception->getMessage();
 		}
 	}
 
-	$userIDs = $Database->query(sprintf('SELECT id FROM %s ORDER BY fullname ASC', User\Attribute::TABLE));
-
-	foreach($userIDs->fetchAll($Database::FETCH_COLUMN) as $userID) {
-		$User = User\Factory::build($userID);
-		$userAttributes[] = [
-			'ID' => $User->get('id'),
-			'FULLNAME' => $User->get('fullname'),
-			'USERNAME' => $User->get('username'),
-		];
+	else {
+		$messages[] = $Language->text('error_security_csrf');
 	}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('post/form');
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'UPDATE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(), CASE_UPPER),
-		'USER_LIST' => $userAttributes ??  [],
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$PostUpdateTemplate = Template\Factory::build('post/update');
-	$PostUpdateTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_post_update'));
-	$MainTemplate->set('HTML', $PostUpdateTemplate);
-	echo $MainTemplate;
 }
 
 #===============================================================================
-# CATCH: Post\Exception
+# Generate user list
 #===============================================================================
-catch(Post\Exception $Exception) {
-	Application::error404();
+foreach($UserRepository->getAll([], 'fullname ASC') as $User) {
+	$userList[] = [
+		'ID' => $User->getID(),
+		'FULLNAME' => $User->get('fullname'),
+		'USERNAME' => $User->get('username'),
+	];
 }
+
+#===============================================================================
+# Build document
+#===============================================================================
+$FormTemplate = Template\Factory::build('post/form');
+$FormTemplate->set('FORM', [
+	'TYPE' => 'UPDATE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($Post->getAll(), CASE_UPPER),
+	'USER_LIST' => $userList ??  [],
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$PostUpdateTemplate = Template\Factory::build('post/update');
+$PostUpdateTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_post_update'));
+$MainTemplate->set('HTML', $PostUpdateTemplate);
+echo $MainTemplate;
diff --git a/admin/user/delete.php b/admin/user/delete.php
index 6f0af6f..758e536 100644
--- a/admin/user/delete.php
+++ b/admin/user/delete.php
@@ -11,46 +11,46 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: User\Exception
+# Get repositories
 #===============================================================================
-try {
-	$User = User\Factory::build(HTTP::GET('id'));
-	$Attribute = $User->getAttribute();
+$UserRepository = Application::getRepository('User');
 
-	if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
-		try {
-			if($Attribute->delete($Database)) {
-				HTTP::redirect(Application::getAdminURL('user/'));
-			}
-		} catch(PDOException $Exception) {
-			$messages[] = $Exception->getMessage();
+#===============================================================================
+# Throw 404 error if user could not be found
+#===============================================================================
+if(!$User = $UserRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
+
+#===============================================================================
+# Check for delete request
+#===============================================================================
+if(HTTP::issetPOST(['token' => Application::getSecurityToken()], 'delete')) {
+	try {
+		if($UserRepository->delete($User)) {
+			HTTP::redirect(Application::getAdminURL('user/'));
 		}
+	} catch(PDOException $Exception) {
+		$messages[] = $Exception->getMessage();
 	}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('user/form');
-	$FormTemplate->set('HTML', parseEntityContent($User));
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'DELETE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(['password']), CASE_UPPER),
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$DeleteTemplate = Template\Factory::build('user/delete');
-	$DeleteTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_user_delete'));
-	$MainTemplate->set('HTML', $DeleteTemplate);
-	echo $MainTemplate;
 }
 
 #===============================================================================
-# CATCH: User\Exception
+# Build document
 #===============================================================================
-catch(User\Exception $Exception) {
-	Application::error404();
-}
+$FormTemplate = Template\Factory::build('user/form');
+$FormTemplate->set('HTML', parseEntityContent($User));
+$FormTemplate->set('FORM', [
+	'TYPE' => 'DELETE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($User->getAll(['password']), CASE_UPPER),
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$DeleteTemplate = Template\Factory::build('user/delete');
+$DeleteTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_user_delete'));
+$MainTemplate->set('HTML', $DeleteTemplate);
+echo $MainTemplate;
diff --git a/admin/user/index.php b/admin/user/index.php
index 8ae4f1a..78219f3 100644
--- a/admin/user/index.php
+++ b/admin/user/index.php
@@ -11,12 +11,18 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('ADMIN.USER.LIST_SIZE');
 $site_sort = Application::get('ADMIN.USER.LIST_SORT');
 
-$lastSite = ceil($Database->query(sprintf('SELECT COUNT(id) FROM %s', User\Attribute::TABLE))->fetchColumn() / $site_size);
+$count = $UserRepository->getCount();
+$lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
 $currentSite = intval($currentSite);
@@ -26,16 +32,16 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 }
 
 #===============================================================================
-# Fetch user IDs from database
+# Get paginated user list
 #===============================================================================
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$userIDs = $Database->query(sprintf($execSQL, User\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+$users = $UserRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($userIDs as $userID) {
-	try {
-		$User = User\Factory::build($userID);
-		$templates[] = generateUserItemTemplate($User);
-	} catch(User\Exception $Exception){}
+foreach($users as $User) {
+	$templates[] = generateUserItemTemplate($User);
 }
 
 #===============================================================================
diff --git a/admin/user/insert.php b/admin/user/insert.php
index acb49ad..96fcb84 100644
--- a/admin/user/insert.php
+++ b/admin/user/insert.php
@@ -10,22 +10,33 @@ define('AUTHENTICATION', TRUE);
 #===============================================================================
 require '../../core/application.php';
 
-$Attribute = new User\Attribute();
+#===============================================================================
+# Get repositories
+#===============================================================================
+$UserRepository = Application::getRepository('User');
 
+#===============================================================================
+# Instantiate new User entity
+#===============================================================================
+$User = new User\Entity;
+
+#===============================================================================
+# Check for insert request
+#===============================================================================
 if(HTTP::issetPOST('slug', 'username', 'password', 'fullname', 'mailaddr', 'body', 'argv', 'time_insert', 'time_update', 'insert')) {
-	$Attribute->set('slug',     HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('username')));
-	$Attribute->set('username', HTTP::POST('username') ? HTTP::POST('username') : NULL);
-	$Attribute->set('password', HTTP::POST('password') ? password_hash(HTTP::POST('password'), PASSWORD_BCRYPT, ['cost' => 10]) : FALSE);
-	$Attribute->set('fullname', HTTP::POST('fullname') ? HTTP::POST('fullname') : NULL);
-	$Attribute->set('mailaddr', HTTP::POST('mailaddr') ? HTTP::POST('mailaddr') : NULL);
-	$Attribute->set('body',     HTTP::POST('body') ? HTTP::POST('body') : NULL);
-	$Attribute->set('argv',     HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-	$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-	$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+	$User->set('slug',     HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('username')));
+	$User->set('username', HTTP::POST('username') ? HTTP::POST('username') : NULL);
+	$User->set('password', HTTP::POST('password') ? password_hash(HTTP::POST('password'), PASSWORD_BCRYPT, ['cost' => 10]) : FALSE);
+	$User->set('fullname', HTTP::POST('fullname') ? HTTP::POST('fullname') : NULL);
+	$User->set('mailaddr', HTTP::POST('mailaddr') ? HTTP::POST('mailaddr') : NULL);
+	$User->set('body',     HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$User->set('argv',     HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$User->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$User->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
 	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
 		try {
-			if($Attribute->insert($Database)) {
+			if($UserRepository->insert($User)) {
 				HTTP::redirect(Application::getAdminURL('user/'));
 			}
 		} catch(PDOException $Exception) {
@@ -45,7 +56,7 @@ $FormTemplate = Template\Factory::build('user/form');
 $FormTemplate->set('FORM', [
 	'TYPE' => 'INSERT',
 	'INFO' => $messages ?? [],
-	'DATA' => array_change_key_case($Attribute->getAll(['password']), CASE_UPPER),
+	'DATA' => array_change_key_case($User->getAll(['password']), CASE_UPPER),
 	'TOKEN' => Application::getSecurityToken()
 ]);
 
diff --git a/admin/user/update.php b/admin/user/update.php
index f53d996..1f3309b 100644
--- a/admin/user/update.php
+++ b/admin/user/update.php
@@ -11,59 +11,59 @@ define('AUTHENTICATION', TRUE);
 require '../../core/application.php';
 
 #===============================================================================
-# TRY: User\Exception
+# Get repositories
 #===============================================================================
-try {
-	$User = User\Factory::build(HTTP::GET('id'));
-	$Attribute = $User->getAttribute();
+$UserRepository = Application::getRepository('User');
 
-	if(HTTP::issetPOST('slug', 'username', 'password', 'fullname', 'mailaddr', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
-		$Attribute->set('slug',     HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('username')));
-		$Attribute->set('username', HTTP::POST('username') ? HTTP::POST('username') : NULL);
-		$Attribute->set('password', HTTP::POST('password') ? password_hash(HTTP::POST('password'), PASSWORD_BCRYPT, ['cost' => 10]) : FALSE);
-		$Attribute->set('fullname', HTTP::POST('fullname') ? HTTP::POST('fullname') : NULL);
-		$Attribute->set('mailaddr', HTTP::POST('mailaddr') ? HTTP::POST('mailaddr') : NULL);
-		$Attribute->set('body',     HTTP::POST('body') ? HTTP::POST('body') : NULL);
-		$Attribute->set('argv',     HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
-		$Attribute->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
-		$Attribute->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
+#===============================================================================
+# Throw 404 error if user could not be found
+#===============================================================================
+if(!$User = $UserRepository->find(HTTP::GET('id'))) {
+	Application::error404();
+}
 
-		if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
-			try {
-				$Attribute->update($Database);
-			} catch(PDOException $Exception) {
-				$messages[] = $Exception->getMessage();
-			}
-		}
+#===============================================================================
+# Check for update request
+#===============================================================================
+if(HTTP::issetPOST('slug', 'username', 'password', 'fullname', 'mailaddr', 'body', 'argv', 'time_insert', 'time_update', 'update')) {
+	$User->set('slug',     HTTP::POST('slug') ? HTTP::POST('slug') : generateSlug(HTTP::POST('username')));
+	$User->set('username', HTTP::POST('username') ? HTTP::POST('username') : NULL);
+	$User->set('password', HTTP::POST('password') ? password_hash(HTTP::POST('password'), PASSWORD_BCRYPT, ['cost' => 10]) : FALSE);
+	$User->set('fullname', HTTP::POST('fullname') ? HTTP::POST('fullname') : NULL);
+	$User->set('mailaddr', HTTP::POST('mailaddr') ? HTTP::POST('mailaddr') : NULL);
+	$User->set('body',     HTTP::POST('body') ? HTTP::POST('body') : NULL);
+	$User->set('argv',     HTTP::POST('argv') ? HTTP::POST('argv') : NULL);
+	$User->set('time_insert', HTTP::POST('time_insert') ?: date('Y-m-d H:i:s'));
+	$User->set('time_update', HTTP::POST('time_update') ?: date('Y-m-d H:i:s'));
 
-		else {
-			$messages[] = $Language->text('error_security_csrf');
+	if(HTTP::issetPOST(['token' => Application::getSecurityToken()])) {
+		try {
+			$UserRepository->update($User);
+		} catch(PDOException $Exception) {
+			$messages[] = $Exception->getMessage();
 		}
 	}
 
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$FormTemplate = Template\Factory::build('user/form');
-	$FormTemplate->set('FORM', [
-		'TYPE' => 'UPDATE',
-		'INFO' => $messages ?? [],
-		'DATA' => array_change_key_case($Attribute->getAll(['password']), CASE_UPPER),
-		'TOKEN' => Application::getSecurityToken()
-	]);
-
-	$InsertTemplate = Template\Factory::build('user/update');
-	$InsertTemplate->set('HTML', $FormTemplate);
-
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('NAME', $Language->text('title_user_update'));
-	$MainTemplate->set('HTML', $InsertTemplate);
-	echo $MainTemplate;
+	else {
+		$messages[] = $Language->text('error_security_csrf');
+	}
 }
 
 #===============================================================================
-# CATCH: User\Exception
+# Build document
 #===============================================================================
-catch(User\Exception $Exception) {
-	Application::error404();
-}
+$FormTemplate = Template\Factory::build('user/form');
+$FormTemplate->set('FORM', [
+	'TYPE' => 'UPDATE',
+	'INFO' => $messages ?? [],
+	'DATA' => array_change_key_case($User->getAll(['password']), CASE_UPPER),
+	'TOKEN' => Application::getSecurityToken()
+]);
+
+$InsertTemplate = Template\Factory::build('user/update');
+$InsertTemplate->set('HTML', $FormTemplate);
+
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('NAME', $Language->text('title_user_update'));
+$MainTemplate->set('HTML', $InsertTemplate);
+echo $MainTemplate;
diff --git a/core/application.php b/core/application.php
index a84669f..e4c481f 100644
--- a/core/application.php
+++ b/core/application.php
@@ -164,9 +164,13 @@ if(Application::get('CORE.SEND_304') === TRUE AND !defined('ADMINISTRATION')) {
 	#===========================================================================
 	$execute = '(SELECT time_update FROM %s ORDER BY time_update DESC LIMIT 1) AS %s';
 
-	$pageSQL = sprintf($execute, Page\Attribute::TABLE, Page\Attribute::TABLE);
-	$postSQL = sprintf($execute, Post\Attribute::TABLE, Post\Attribute::TABLE);
-	$userSQL = sprintf($execute, User\Attribute::TABLE, User\Attribute::TABLE);
+	$pageTable = Page\Repository::getTableName();
+	$postTable = Post\Repository::getTableName();
+	$userTable = User\Repository::getTableName();
+
+	$pageSQL = sprintf($execute, $pageTable, $pageTable);
+	$postSQL = sprintf($execute, $postTable, $postTable);
+	$userSQL = sprintf($execute, $postTable, $postTable);
 
 	$Statement = $Database->query("SELECT {$pageSQL}, {$postSQL}, {$userSQL}");
 
diff --git a/core/functions.php b/core/functions.php
index 31a295b..55744f1 100644
--- a/core/functions.php
+++ b/core/functions.php
@@ -1,16 +1,20 @@
 <?php
+use Page\Entity as Page;
+use Post\Entity as Post;
+use User\Entity as User;
+use Template\Template as Template;
+use Template\Factory as TemplateFactory;
+
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generateNaviTemplate(int $current, $location, $namespace): Template\Template {
-	$Database = Application::getDatabase();
-	$Attribute = "{$namespace}\\Attribute";
-
-	$Statement = $Database->query(sprintf('SELECT COUNT(id) FROM %s', $Attribute::TABLE));
+function generateNaviTemplate(int $current, $location, $namespace): Template {
+	$Repository = Application::getRepository($namespace);
 
-	$lastSite = ceil($Statement->fetchColumn() / Application::get(strtoupper($namespace).'.LIST_SIZE'));
+	$listSize = Application::get(strtoupper($namespace).'.LIST_SIZE');
+	$lastSite = ceil($Repository->getCount() / $listSize);
 
-	$PaginationTemplate = Template\Factory::build('pagination');
+	$PaginationTemplate = TemplateFactory::build('pagination');
 	$PaginationTemplate->set('THIS', $current);
 	$PaginationTemplate->set('LAST', $lastSite);
 	$PaginationTemplate->set('HREF', "{$location}?site=%d");
@@ -21,29 +25,29 @@ function generateNaviTemplate(int $current, $location, $namespace): Template\Tem
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generatePageNaviTemplate($current): Template\Template {
+function generatePageNaviTemplate($current): Template {
 	return generateNaviTemplate($current, Application::getPageURL(), 'Page');
 }
 
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generatePostNaviTemplate($current): Template\Template {
+function generatePostNaviTemplate($current): Template {
 	return generateNaviTemplate($current, Application::getPostURL(), 'Post');
 }
 
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generateUserNaviTemplate($current): Template\Template {
+function generateUserNaviTemplate($current): Template {
 	return generateNaviTemplate($current, Application::getUserURL(), 'User');
 }
 
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generatePageItemTemplate(Page\Item $Page, User\Item $User): Template\Template {
-	$Template = Template\Factory::build('page/item');
+function generatePageItemTemplate(Page $Page, User $User): Template {
+	$Template = TemplateFactory::build('page/item');
 	$Template->set('PAGE', generateItemTemplateData($Page));
 	$Template->set('USER', generateItemTemplateData($User));
 
@@ -53,8 +57,8 @@ function generatePageItemTemplate(Page\Item $Page, User\Item $User): Template\Te
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generatePostItemTemplate(Post\Item $Post, User\Item $User): Template\Template {
-	$Template = Template\Factory::build('post/item');
+function generatePostItemTemplate(Post $Post, User $User): Template {
+	$Template = TemplateFactory::build('post/item');
 	$Template->set('POST', generateItemTemplateData($Post));
 	$Template->set('USER', generateItemTemplateData($User));
 
@@ -64,8 +68,8 @@ function generatePostItemTemplate(Post\Item $Post, User\Item $User): Template\Te
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generateUserItemTemplate(User\Item $User): Template\Template {
-	$Template = Template\Factory::build('user/item');
+function generateUserItemTemplate(User $User): Template {
+	$Template = TemplateFactory::build('user/item');
 	$Template->set('USER', generateItemTemplateData($User));
 
 	return $Template;
@@ -74,16 +78,16 @@ function generateUserItemTemplate(User\Item $User): Template\Template {
 #===============================================================================
 # Helper function to reduce duplicate code
 #===============================================================================
-function generateItemTemplateData(Item $Item): array {
-	$ATTR = $Item->getAttribute()->getAll(['password']);
+function generateItemTemplateData(EntityInterface $Entity): array {
+	$ATTR = $Entity->getAll(['password']);
 	$ATTR = array_change_key_case($ATTR, CASE_UPPER);
 
-	$preparsed = parseContentTags($Item->get('body'));
+	$preparsed = parseContentTags($Entity->get('body'));
 
 	return [
-		'URL' => Application::getEntityURL($Item),
-		'GUID' => generatePseudoGUID($Item),
-		'ARGV' => parseArguments($Item->get('argv')),
+		'URL' => Application::getEntityURL($Entity),
+		'GUID' => generatePseudoGUID($Entity),
+		'ARGV' => parseArguments($Entity->get('argv')),
 
 		'ATTR' => $ATTR,
 
@@ -95,11 +99,11 @@ function generateItemTemplateData(Item $Item): array {
 		],
 
 		'BODY' => [
-			'TEXT' => function() use($Item) {
+			'TEXT' => function() use($Entity) {
 				return $preparsed;
 			},
-			'HTML' => function() use($Item) {
-				return parseEntityContent($Item);
+			'HTML' => function() use($Entity) {
+				return parseEntityContent($Entity);
 			}
 		]
 	];
@@ -108,12 +112,12 @@ function generateItemTemplateData(Item $Item): array {
 #===============================================================================
 # Generate pseudo GUID for entity
 #===============================================================================
-function generatePseudoGUID(Item $Entity) {
+function generatePseudoGUID(EntityInterface $Entity) {
 	switch(get_class($Entity)) {
-		case "Page\Item":
+		case "Page\Entity":
 			$attr = Application::get('PAGE.FEED_GUID');
 			break;
-		case "Post\Item":
+		case "Post\Entity":
 			$attr = Application::get('POST.FEED_GUID');
 			break;
 		default:
@@ -134,12 +138,14 @@ function parseContentTags(string $text): string {
 	$entity_tags = '#\{(POST|PAGE|USER)\[([0-9]+)\]\}#';
 
 	$text = preg_replace_callback($entity_tags, function($matches) {
-		$namespace = ucfirst(strtolower($matches[1])).'\\Factory';
+		$namespace = ucfirst(strtolower($matches[1]));
+		$Repository = Application::getRepository($namespace);
 
-		try {
-			$Entity = $namespace::build($matches[2]);
+		if($Entity = $Repository->find($matches[2])) {
 			return Application::getEntityURL($Entity);
-		} catch(Exception $Exception) {
+		}
+
+		else {
 			return '{undefined}';
 		}
 	}, $text);
@@ -156,15 +162,15 @@ function parseContentTags(string $text): string {
 #===============================================================================
 # Parse entity content
 #===============================================================================
-function parseEntityContent(Item $Item): string {
-	switch($class = get_class($Item)) {
-		case 'Page\Item':
+function parseEntityContent(EntityInterface $Entity): string {
+	switch($class = get_class($Entity)) {
+		case 'Page\Entity':
 			$prefix = 'PAGE';
 			break;
-		case 'Post\Item':
+		case 'Post\Entity':
 			$prefix = 'POST';
 			break;
-		case 'User\Item':
+		case 'User\Entity':
 			$prefix = 'USER';
 			break;
 		default:
@@ -175,7 +181,7 @@ function parseEntityContent(Item $Item): string {
 	$Parsedown = new Parsedown();
 	$Parsedown->setUrlsLinked(FALSE);
 
-	$text = parseContentTags($Item->get('body'));
+	$text = parseContentTags($Entity->get('body'));
 
 	if(Application::get("$prefix.EMOTICONS")) {
 		$text = parseUnicodeEmoticons($text);
@@ -409,34 +415,37 @@ function generateSlug($string, $separator = '-') {
 # Function to get data from specific page in templates
 #===============================================================================
 function PAGE(int $id): array {
-	try {
-		$Page = Page\Factory::build($id);
+	$Repository = Application::getRepository('Page');
+
+	if($Page = $Repository->find($id)) {
 		return generateItemTemplateData($Page);
-	} catch(Page\Exception $Exception) {
-		return [];
 	}
+
+	return [];
 }
 
 #===============================================================================
 # Function to get data from specific post in templates
 #===============================================================================
 function POST(int $id): array {
-	try {
-		$Post = Post\Factory::build($id);
+	$Repository = Application::getRepository('Post');
+
+	if($Post = $Repository->find($id)) {
 		return generateItemTemplateData($Post);
-	} catch(Post\Exception $Exception) {
-		return [];
 	}
+
+	return [];
 }
 
 #===============================================================================
 # Function to get data from specific user in templates
 #===============================================================================
 function USER(int $id): array {
-	try {
-		$User = User\Factory::build($id);
+	$Repository = Application::getRepository('User');
+
+	if($User = $Repository->find($id)) {
 		return generateItemTemplateData($User);
-	} catch(User\Exception $Exception) {
-		return [];
 	}
+
+	return [];
 }
diff --git a/core/include/feed/main.php b/core/include/feed/main.php
index 4dc7c81..637c54b 100644
--- a/core/include/feed/main.php
+++ b/core/include/feed/main.php
@@ -1,9 +1,8 @@
 <?php
 #===============================================================================
-# Get instances
+# Get repositories
 #===============================================================================
-$Database = Application::getDatabase();
-$Language = Application::getLanguage();
+$UserRepository = Application::getRepository('User');
 
 #===============================================================================
 # HEADER: Content-Type for XML document
@@ -14,26 +13,21 @@ HTTP::responseHeader(HTTP::HEADER_CONTENT_TYPE, HTTP::CONTENT_TYPE_XML);
 # Post feed
 #===============================================================================
 if(!isset($param) OR $param !== 'page') {
-	$POST['FEED_SORT'] = Application::get('POST.FEED_SORT');
-	$POST['FEED_SIZE'] = Application::get('POST.FEED_SIZE');
+	$PostRepository = Application::getRepository('Post');
 
-	$execSQL = "SELECT id FROM %s ORDER BY {$POST['FEED_SORT']} LIMIT {$POST['FEED_SIZE']}";
-	$postIDs = $Database->query(sprintf($execSQL, Post\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+	$posts = $PostRepository->getPaginated(
+		Application::get('POST.FEED_SORT'),
+		Application::get('POST.FEED_SIZE')
+	);
 
-	foreach($postIDs as $postID) {
-		try {
-			$Post = Post\Factory::build($postID);
-			$User = User\Factory::build($Post->get('user'));
+	foreach($posts as $Post) {
+		$User = $UserRepository->find($Post->get('user'));
 
-			$ItemTemplate = Template\Factory::build('feed/item_post');
-			$ItemTemplate->set('POST', generateItemTemplateData($Post));
-			$ItemTemplate->set('USER', generateItemTemplateData($User));
+		$ItemTemplate = Template\Factory::build('feed/item_post');
+		$ItemTemplate->set('POST', generateItemTemplateData($Post));
+		$ItemTemplate->set('USER', generateItemTemplateData($User));
 
-			$post_templates[] = $ItemTemplate;
-		}
-
-		catch(Post\Exception $Exception){}
-		catch(User\Exception $Exception){}
+		$post_templates[] = $ItemTemplate;
 	}
 }
 
@@ -41,26 +35,21 @@ if(!isset($param) OR $param !== 'page') {
 # Page feed
 #===============================================================================
 if(!isset($param) OR $param !== 'post') {
-	$PAGE['FEED_SORT'] = Application::get('PAGE.FEED_SORT');
-	$PAGE['FEED_SIZE'] = Application::get('PAGE.FEED_SIZE');
-
-	$execSQL = "SELECT id FROM %s ORDER BY {$PAGE['FEED_SORT']} LIMIT {$PAGE['FEED_SIZE']}";
-	$pageIDs = $Database->query(sprintf($execSQL, Page\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+	$PageRepository = Application::getRepository('Page');
 
-	foreach($pageIDs as $pageID) {
-		try {
-			$Page = Page\Factory::build($pageID);
-			$User = User\Factory::build($Page->get('user'));
+	$pages = $PageRepository->getPaginated(
+		Application::get('PAGE.FEED_SORT'),
+		Application::get('PAGE.FEED_SIZE')
+	);
 
-			$ItemTemplate = Template\Factory::build('feed/item_page');
-			$ItemTemplate->set('PAGE', generateItemTemplateData($Page));
-			$ItemTemplate->set('USER', generateItemTemplateData($User));
+	foreach($pages as $Page) {
+		$User = $UserRepository->find($Page->get('user'));
 
-			$page_templates[] = $ItemTemplate;
-		}
+		$ItemTemplate = Template\Factory::build('feed/item_page');
+		$ItemTemplate->set('PAGE', generateItemTemplateData($Page));
+		$ItemTemplate->set('USER', generateItemTemplateData($User));
 
-		catch(Page\Exception $Exception){}
-		catch(User\Exception $Exception){}
+		$page_templates[] = $ItemTemplate;
 	}
 }
 
diff --git a/core/include/home.php b/core/include/home.php
index 76c9287..bc73bef 100644
--- a/core/include/home.php
+++ b/core/include/home.php
@@ -1,23 +1,21 @@
 <?php
 #===============================================================================
-# Get instances
+# Get repositories
 #===============================================================================
-$Database = Application::getDatabase();
-$Language = Application::getLanguage();
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
-$execSQL = 'SELECT id FROM %s ORDER BY '.Application::get('POST.LIST_SORT').' LIMIT '.Application::get('POST.LIST_SIZE');
-$Statement = $Database->query(sprintf($execSQL, Post\Attribute::TABLE));
-
-$postIDs = $Statement->fetchAll($Database::FETCH_COLUMN);
+#===============================================================================
+# Get paginated post list
+#===============================================================================
+$posts = $PostRepository->getPaginated(
+	Application::get('POST.LIST_SORT'),
+	Application::get('POST.LIST_SIZE')
+);
 
-foreach($postIDs as $postID) {
-	try {
-		$Post = Post\Factory::build($postID);
-		$User = User\Factory::build($Post->get('user'));
-		$templates[] = generatePostItemTemplate($Post, $User);
-	}
-	catch(Post\Exception $Exception){}
-	catch(User\Exception $Exception){}
+foreach($posts as $Post) {
+	$User = $UserRepository->find($Post->get('user'));
+	$templates[] = generatePostItemTemplate($Post, $User);
 }
 
 #===============================================================================
@@ -35,7 +33,8 @@ $MainTemplate = Template\Factory::build('main');
 $MainTemplate->set('HTML', $HomeTemplate);
 $MainTemplate->set('HEAD', [
 	'NAME' => Application::get('BLOGMETA.HOME'),
-	'DESC' => Application::get('BLOGMETA.NAME').' – '.Application::get('BLOGMETA.DESC'),
+	'DESC' => Application::get('BLOGMETA.NAME').' – '
+		.Application::get('BLOGMETA.DESC'),
 	'PERM' => Application::getURL()
 ]);
 
diff --git a/core/include/page/list.php b/core/include/page/list.php
index 7618009..f7541fa 100644
--- a/core/include/page/list.php
+++ b/core/include/page/list.php
@@ -2,16 +2,21 @@
 #===============================================================================
 # Get instances
 #===============================================================================
-$Database = Application::getDatabase();
 $Language = Application::getLanguage();
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$PageRepository = Application::getRepository('Page');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('PAGE.LIST_SIZE');
 $site_sort = Application::get('PAGE.LIST_SORT');
 
-$count = $Database->query(sprintf('SELECT COUNT(id) FROM %s', Page\Attribute::TABLE))->fetchColumn();
+$count = $PageRepository->getCount();
 $lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
@@ -24,23 +29,23 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 #===============================================================================
 # Single redirect
 #===============================================================================
-if(Application::get('PAGE.SINGLE_REDIRECT') === TRUE AND $count === '1') {
-	$Statement = $Database->query(sprintf('SELECT id FROM %s LIMIT 1', Page\Attribute::TABLE));
-	$Page = Page\Factory::build($Statement->fetchColumn());
+if(Application::get('PAGE.SINGLE_REDIRECT') === TRUE AND $count === 1) {
+	$Page = $PageRepository->getLast();
 	HTTP::redirect(Application::getEntityURL($Page));
 }
 
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$pageIDs = $Database->query(sprintf($execSQL, Page\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+#===============================================================================
+# Get paginated page list
+#===============================================================================
+$pages = $PageRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($pageIDs as $pageID) {
-	try {
-		$Page = Page\Factory::build($pageID);
-		$User = User\Factory::build($Page->get('user'));
-		$templates[] = generatePageItemTemplate($Page, $User);
-	}
-	catch(Page\Exception $Exception){}
-	catch(User\Exception $Exception){}
+foreach($pages as $Page) {
+	$User = $UserRepository->find($Page->get('user'));
+	$templates[] = generatePageItemTemplate($Page, $User);
 }
 
 #===============================================================================
diff --git a/core/include/page/main.php b/core/include/page/main.php
index 01ef40d..39e1d3c 100644
--- a/core/include/page/main.php
+++ b/core/include/page/main.php
@@ -1,79 +1,72 @@
 <?php
 #===============================================================================
-# Get instances
+# Get repositories
 #===============================================================================
-$Database = Application::getDatabase();
-$Language = Application::getLanguage();
+$PageRepository = Application::getRepository('Page');
+$UserRepository = Application::getRepository('User');
 
 #===============================================================================
-# TRY: Page\Exception
+# Try to find page by slug URL or unique ID
 #===============================================================================
-try {
-	if(Application::get('PAGE.SLUG_URLS')) {
-		$Page = Page\Factory::buildBySlug($param);
+if(Application::get('PAGE.SLUG_URLS')) {
+	if(!$Page = $PageRepository->findBy('slug', $param)) {
+		if($Page = $PageRepository->find($param)) {
+			HTTP::redirect(Application::getEntityURL($Page));
+		}
 	}
+}
 
-	else {
-		$Page = Page\Factory::build($param);
+else {
+	if(!$Page = $PageRepository->find($param)) {
+		if($Page = $PageRepository->findBy('slug', $param)) {
+			HTTP::redirect(Application::getEntityURL($Page));
+		}
 	}
+}
 
-	$User = User\Factory::build($Page->get('user'));
-
-	$page_data = generateItemTemplateData($Page);
-	$user_data = generateItemTemplateData($User);
-
-	#===============================================================================
-	# Add page data for previous and next page
-	#===============================================================================
-	try {
-		$PrevPage = Page\Factory::build($Page->getPrevID());
-		$page_data['PREV'] = generateItemTemplateData($PrevPage);
-	} catch(Page\Exception $Exception){}
-
-	try {
-		$NextPage = Page\Factory::build($Page->getNextID());
-		$page_data['NEXT'] = generateItemTemplateData($NextPage);
-	} catch(Page\Exception $Exception){}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$PageTemplate = Template\Factory::build('page/main');
-	$PageTemplate->set('PAGE', $page_data);
-	$PageTemplate->set('USER', $user_data);
+#===============================================================================
+# Throw 404 error if page could not be found
+#===============================================================================
+if(!isset($Page)) {
+	Application::error404();
+}
 
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('HTML', $PageTemplate);
-	$MainTemplate->set('HEAD', [
-		'NAME' => $page_data['ATTR']['NAME'],
-		'DESC' => description($page_data['BODY']['HTML'](), Application::get('PAGE.DESCRIPTION_SIZE')),
-		'PERM' => $page_data['URL'],
-		'OG_IMAGES' => $page_data['FILE']['LIST']
-	]);
+#===============================================================================
+# Generate template data
+#===============================================================================
+$User = $UserRepository->find($Page->get('user'));
+$page_data = generateItemTemplateData($Page);
+$user_data = generateItemTemplateData($User);
 
-	# Get access to the current item data from main template
-	$MainTemplate->set('TYPE', 'PAGE');
-	$MainTemplate->set('PAGE', $page_data);
-	$MainTemplate->set('USER', $user_data);
+#===============================================================================
+# Add template data for previous and next page
+#===============================================================================
+if($PrevPage = $PageRepository->findPrev($Page)) {
+	$page_data['PREV'] = generateItemTemplateData($PrevPage);
+}
 
-	echo $MainTemplate;
+if($NextPage = $PageRepository->findNext($Page)) {
+	$page_data['NEXT'] = generateItemTemplateData($NextPage);
 }
 
 #===============================================================================
-# CATCH: Page\Exception
+# Build document
 #===============================================================================
-catch(Page\Exception $Exception) {
-	try {
-		if(Application::get('PAGE.SLUG_URLS') === FALSE) {
-			$Page = Page\Factory::buildBySlug($param);
-		} else {
-			$Page = Page\Factory::build($param);
-		}
+$PageTemplate = Template\Factory::build('page/main');
+$PageTemplate->set('PAGE', $page_data);
+$PageTemplate->set('USER', $user_data);
 
-		HTTP::redirect(Application::getEntityURL($Page));
-	}
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('TYPE', 'PAGE');
+$MainTemplate->set('PAGE', $page_data);
+$MainTemplate->set('USER', $user_data);
+$MainTemplate->set('HTML', $PageTemplate);
+$MainTemplate->set('HEAD', [
+	'NAME' => $page_data['ATTR']['NAME'],
+	'DESC' => description($page_data['BODY']['HTML'](),
+		Application::get('PAGE.DESCRIPTION_SIZE')),
+	'PERM' => $page_data['URL'],
+	'OG_IMAGES' => $page_data['FILE']['LIST']
+]);
 
-	catch(Page\Exception $Exception) {
-		Application::error404();
-	}
-}
+echo $MainTemplate;
diff --git a/core/include/post/list.php b/core/include/post/list.php
index 84de108..4599883 100644
--- a/core/include/post/list.php
+++ b/core/include/post/list.php
@@ -2,16 +2,21 @@
 #===============================================================================
 # Get instances
 #===============================================================================
-$Database = Application::getDatabase();
 $Language = Application::getLanguage();
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('POST.LIST_SIZE');
 $site_sort = Application::get('POST.LIST_SORT');
 
-$count = $Database->query(sprintf('SELECT COUNT(id) FROM %s', Post\Attribute::TABLE))->fetchColumn();
+$count = $PostRepository->getCount();
 $lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
@@ -24,23 +29,23 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 #===============================================================================
 # Single redirect
 #===============================================================================
-if(Application::get('POST.SINGLE_REDIRECT') === TRUE AND $count === '1') {
-	$Statement = $Database->query(sprintf('SELECT id FROM %s LIMIT 1', Post\Attribute::TABLE));
-	$Post = Post\Factory::build($Statement->fetchColumn());
+if(Application::get('POST.SINGLE_REDIRECT') === TRUE AND $count === 1) {
+	$Post = $PostRepository->getLast();
 	HTTP::redirect(Application::getEntityURL($Post));
 }
 
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$postIDs = $Database->query(sprintf($execSQL, Post\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+#===============================================================================
+# Get paginated post list
+#===============================================================================
+$posts = $PostRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($postIDs as $postID) {
-	try {
-		$Post = Post\Factory::build($postID);
-		$User = User\Factory::build($Post->get('user'));
-		$templates[] = generatePostItemTemplate($Post, $User);
-	}
-	catch(Post\Exception $Exception){}
-	catch(User\Exception $Exception){}
+foreach($posts as $Post) {
+	$User = $UserRepository->find($Post->get('user'));
+	$templates[] = generatePostItemTemplate($Post, $User);
 }
 
 #===============================================================================
diff --git a/core/include/post/main.php b/core/include/post/main.php
index 57cc402..86008f6 100644
--- a/core/include/post/main.php
+++ b/core/include/post/main.php
@@ -1,79 +1,72 @@
 <?php
 #===============================================================================
-# Get instances
+# Get repositories
 #===============================================================================
-$Database = Application::getDatabase();
-$Language = Application::getLanguage();
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
 #===============================================================================
-# TRY: Post\Exception
+# Try to find post by slug URL or unique ID
 #===============================================================================
-try {
-	if(Application::get('POST.SLUG_URLS')) {
-		$Post = Post\Factory::buildBySlug($param);
+if(Application::get('POST.SLUG_URLS')) {
+	if(!$Post = $PostRepository->findBy('slug', $param)) {
+		if($Post = $PostRepository->find($param)) {
+			HTTP::redirect(Application::getEntityURL($Post));
+		}
 	}
+}
 
-	else {
-		$Post = Post\Factory::build($param);
+else {
+	if(!$Post = $PostRepository->find($param)) {
+		if($Post = $PostRepository->findBy('slug', $param)) {
+			HTTP::redirect(Application::getEntityURL($Post));
+		}
 	}
+}
 
-	$User = User\Factory::build($Post->get('user'));
-
-	$post_data = generateItemTemplateData($Post);
-	$user_data = generateItemTemplateData($User);
-
-	#===============================================================================
-	# Add post data for previous and next post
-	#===============================================================================
-	try {
-		$PrevPost = Post\Factory::build($Post->getPrevID());
-		$post_data['PREV'] = generateItemTemplateData($PrevPost);
-	} catch(Post\Exception $Exception){}
-
-	try {
-		$NextPost = Post\Factory::build($Post->getNextID());
-		$post_data['NEXT'] = generateItemTemplateData($NextPost);
-	} catch(Post\Exception $Exception){}
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$PostTemplate = Template\Factory::build('post/main');
-	$PostTemplate->set('POST', $post_data);
-	$PostTemplate->set('USER', $user_data);
+#===============================================================================
+# Throw 404 error if post could not be found
+#===============================================================================
+if(!isset($Post)) {
+	Application::error404();
+}
 
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('HTML', $PostTemplate);
-	$MainTemplate->set('HEAD', [
-		'NAME' => $post_data['ATTR']['NAME'],
-		'DESC' => description($post_data['BODY']['HTML'](), Application::get('POST.DESCRIPTION_SIZE')),
-		'PERM' => $post_data['URL'],
-		'OG_IMAGES' => $post_data['FILE']['LIST']
-	]);
+#===============================================================================
+# Generate template data
+#===============================================================================
+$User = $UserRepository->find($Post->get('user'));
+$post_data = generateItemTemplateData($Post);
+$user_data = generateItemTemplateData($User);
 
-	# Get access to the current item data from main template
-	$MainTemplate->set('TYPE', 'POST');
-	$MainTemplate->set('POST', $post_data);
-	$MainTemplate->set('USER', $user_data);
+#===============================================================================
+# Add template data for previous and next post
+#===============================================================================
+if($PrevPost = $PostRepository->findPrev($Post)) {
+	$post_data['PREV'] = generateItemTemplateData($PrevPost);
+}
 
-	echo $MainTemplate;
+if($NextPost = $PostRepository->findNext($Post)) {
+	$post_data['NEXT'] = generateItemTemplateData($NextPost);
 }
 
 #===============================================================================
-# CATCH: Post\Exception
+# Build document
 #===============================================================================
-catch(Post\Exception $Exception) {
-	try {
-		if(Application::get('POST.SLUG_URLS') === FALSE) {
-			$Post = Post\Factory::buildBySlug($param);
-		} else {
-			$Post = Post\Factory::build($param);
-		}
+$PostTemplate = Template\Factory::build('post/main');
+$PostTemplate->set('POST', $post_data);
+$PostTemplate->set('USER', $user_data);
 
-		HTTP::redirect(Application::getEntityURL($Post));
-	}
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('TYPE', 'POST');
+$MainTemplate->set('POST', $post_data);
+$MainTemplate->set('USER', $user_data);
+$MainTemplate->set('HTML', $PostTemplate);
+$MainTemplate->set('HEAD', [
+	'NAME' => $post_data['ATTR']['NAME'],
+	'DESC' => description($post_data['BODY']['HTML'](),
+		Application::get('POST.DESCRIPTION_SIZE')),
+	'PERM' => $post_data['URL'],
+	'OG_IMAGES' => $post_data['FILE']['LIST']
+]);
 
-	catch(Post\Exception $Exception) {
-		Application::error404();
-	}
-}
+echo $MainTemplate;
diff --git a/core/include/search/main.php b/core/include/search/main.php
index 6bc6bdc..564f0dd 100644
--- a/core/include/search/main.php
+++ b/core/include/search/main.php
@@ -2,15 +2,22 @@
 #===============================================================================
 # Get instances
 #===============================================================================
-$Database = Application::getDatabase();
 $Language = Application::getLanguage();
 
-$D_LIST = $Database->query(sprintf('SELECT DISTINCT DAY(time_insert) AS temp FROM %s ORDER BY temp', Post\Attribute::TABLE));
-$M_LIST = $Database->query(sprintf('SELECT DISTINCT MONTH(time_insert) AS temp FROM %s ORDER BY temp', Post\Attribute::TABLE));
-$Y_LIST = $Database->query(sprintf('SELECT DISTINCT YEAR(time_insert) AS temp FROM %s ORDER BY temp', Post\Attribute::TABLE));
+#===============================================================================
+# Get repositories
+#===============================================================================
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
 if($search = HTTP::GET('q')) {
-	if(!$postIDs = Post\Item::getSearchResultIDs($search, [HTTP::GET('d'), HTTP::GET('m'), HTTP::GET('y')], $Database)) {
+	$filter = [
+		'day'   => HTTP::GET('d'),
+		'month' => HTTP::GET('m'),
+		'year'  => HTTP::GET('y')
+	];
+
+	if(!$posts = $PostRepository->search($search, $filter)) {
 		$message = $Language->text('search_no_results', escapeHTML($search));
 	}
 }
@@ -22,9 +29,9 @@ $form_data = [
 		'Y' => HTTP::GET('y'),
 	],
 	'OPTIONS' => [
-		'D' => $D_LIST->fetchAll($Database::FETCH_COLUMN),
-		'M' => $M_LIST->fetchAll($Database::FETCH_COLUMN),
-		'Y' => $Y_LIST->fetchAll($Database::FETCH_COLUMN),
+		'D' => $PostRepository->getDistinctDays(),
+		'M' => $PostRepository->getDistinctMonths(),
+		'Y' => $PostRepository->getDistinctYears(),
 	]
 ];
 
@@ -36,15 +43,10 @@ $search_data = [
 #===============================================================================
 # Build document
 #===============================================================================
-if(isset($postIDs) AND !empty($postIDs)) {
-	foreach($postIDs as $postID) {
-		try {
-			$Post = Post\Factory::build($postID);
-			$User = User\Factory::build($Post->get('user'));
-			$templates[] = generatePostItemTemplate($Post, $User);
-		}
-		catch(Post\Exception $Exception){}
-		catch(User\Exception $Exception){}
+if(!empty($posts)) {
+	foreach($posts as $Post) {
+		$User = $UserRepository->find($Post->get('user'));
+		$templates[] = generatePostItemTemplate($Post, $User);
 	}
 
 	$ResultTemplate = Template\Factory::build('search/result');
diff --git a/core/include/user/list.php b/core/include/user/list.php
index b64eee5..f6f794a 100644
--- a/core/include/user/list.php
+++ b/core/include/user/list.php
@@ -2,16 +2,20 @@
 #===============================================================================
 # Get instances
 #===============================================================================
-$Database = Application::getDatabase();
 $Language = Application::getLanguage();
 
 #===============================================================================
+# Get repositories
+#===============================================================================
+$UserRepository = Application::getRepository('User');
+
+#===============================================================================
 # Pagination
 #===============================================================================
 $site_size = Application::get('USER.LIST_SIZE');
 $site_sort = Application::get('USER.LIST_SORT');
 
-$count = $Database->query(sprintf('SELECT COUNT(id) FROM %s', User\Attribute::TABLE))->fetchColumn();
+$count = $UserRepository->getCount();
 $lastSite = ceil($count / $site_size);
 
 $currentSite = HTTP::GET('site') ?? 1;
@@ -24,20 +28,22 @@ if($currentSite < 1 OR ($currentSite > $lastSite AND $lastSite > 0)) {
 #===============================================================================
 # Single redirect
 #===============================================================================
-if(Application::get('USER.SINGLE_REDIRECT') === TRUE AND $count === '1') {
-	$Statement = $Database->query(sprintf('SELECT id FROM %s LIMIT 1', User\Attribute::TABLE));
-	$User = User\Factory::build($Statement->fetchColumn());
+if(Application::get('USER.SINGLE_REDIRECT') === TRUE AND $count === 1) {
+	$User = $UserRepository->getLast();
 	HTTP::redirect(Application::getEntityURL($User));
 }
 
-$execSQL = "SELECT id FROM %s ORDER BY {$site_sort} LIMIT ".(($currentSite-1) * $site_size).", {$site_size}";
-$userIDs = $Database->query(sprintf($execSQL, User\Attribute::TABLE))->fetchAll($Database::FETCH_COLUMN);
+#===============================================================================
+# Get paginated user list
+#===============================================================================
+$users = $UserRepository->getPaginated(
+	$site_sort,
+	$site_size,
+	($currentSite-1) * $site_size
+);
 
-foreach($userIDs as $userID) {
-	try {
-		$User = User\Factory::build($userID);
-		$templates[] = generateUserItemTemplate($User);
-	} catch(User\Exception $Exception){}
+foreach($users as $User) {
+	$templates[] = generateUserItemTemplate($User);
 }
 
 #===============================================================================
diff --git a/core/include/user/main.php b/core/include/user/main.php
index 34ec883..c0cb20d 100644
--- a/core/include/user/main.php
+++ b/core/include/user/main.php
@@ -1,81 +1,73 @@
 <?php
 #===============================================================================
-# Get instances
+# Get repositories
 #===============================================================================
-$Database = Application::getDatabase();
-$Language = Application::getLanguage();
+$PageRepository = Application::getRepository('Page');
+$PostRepository = Application::getRepository('Post');
+$UserRepository = Application::getRepository('User');
 
 #===============================================================================
-# TRY: User\Exception
+# Try to find user by slug URL or unique ID
 #===============================================================================
-try {
-	if(Application::get('USER.SLUG_URLS')) {
-		$User = User\Factory::buildBySlug($param);
+if(Application::get('USER.SLUG_URLS')) {
+	if(!$User = $UserRepository->findBy('slug', $param)) {
+		if($User = $UserRepository->find($param)) {
+			HTTP::redirect(Application::getEntityURL($User));
+		}
 	}
+}
 
-	else {
-		$User = User\Factory::build($param);
+else {
+	if(!$User = $UserRepository->find($param)) {
+		if($User = $UserRepository->findBy('slug', $param)) {
+			HTTP::redirect(Application::getEntityURL($User));
+		}
 	}
+}
 
-	$user_data = generateItemTemplateData($User);
-
-	#===============================================================================
-	# Add user data for previous and next user
-	#===============================================================================
-	try {
-		$PrevUser = User\Factory::build($User->getPrevID());
-		$user_data['PREV'] = generateItemTemplateData($PrevUser);
-	} catch(User\Exception $Exception){}
-
-	try {
-		$NextUser = User\Factory::build($User->getNextID());
-		$user_data['NEXT'] = generateItemTemplateData($NextUser);
-	} catch(User\Exception $Exception){}
-
-	$PostCountStatement = $Database->query(sprintf('SELECT COUNT(*) FROM %s WHERE user = %d', Post\Attribute::TABLE, $User->getID()));
-	$PageCountStatement = $Database->query(sprintf('SELECT COUNT(*) FROM %s WHERE user = %d', Page\Attribute::TABLE, $User->getID()));
-
-	#===============================================================================
-	# Build document
-	#===============================================================================
-	$UserTemplate = Template\Factory::build('user/main');
-	$UserTemplate->set('USER', $user_data);
-	$UserTemplate->set('COUNT', [
-		'POST' => $PostCountStatement->fetchColumn(),
-		'PAGE' => $PageCountStatement->fetchColumn()
-	]);
+#===============================================================================
+# Throw 404 error if user could not be found
+#===============================================================================
+if(!isset($User)) {
+	Application::error404();
+}
 
-	$MainTemplate = Template\Factory::build('main');
-	$MainTemplate->set('HTML', $UserTemplate);
-	$MainTemplate->set('HEAD', [
-		'NAME' => $user_data['ATTR']['FULLNAME'],
-		'DESC' => description($user_data['BODY']['HTML'](), Application::get('USER.DESCRIPTION_SIZE')),
-		'PERM' => $user_data['URL'],
-		'OG_IMAGES' => $user_data['FILE']['LIST']
-	]);
+#===============================================================================
+# Generate template data
+#===============================================================================
+$user_data = generateItemTemplateData($User);
 
-	# Get access to the current item data from main template
-	$MainTemplate->set('TYPE', 'USER');
-	$MainTemplate->set('USER', $user_data);
+#===============================================================================
+# Add template data for previous and next user
+#===============================================================================
+if($PrevUser = $UserRepository->findPrev($User)) {
+	$user_data['PREV'] = generateItemTemplateData($PrevUser);
+}
 
-	echo $MainTemplate;
+if($NextUser = $UserRepository->findNext($User)) {
+	$user_data['NEXT'] = generateItemTemplateData($NextUser);
 }
 
 #===============================================================================
-# CATCH: User\Exception
+# Build document
 #===============================================================================
-catch(User\Exception $Exception) {
-	try {
-		if(Application::get('USER.SLUG_URLS') === FALSE) {
-			$User = User\Factory::buildBySlug($param);
-		} else {
-			$User = User\Factory::build($param);
-		}
+$UserTemplate = Template\Factory::build('user/main');
+$UserTemplate->set('USER', $user_data);
+$UserTemplate->set('COUNT', [
+	'POST' => $PostRepository->getCountByUser($User),
+	'PAGE' => $PageRepository->getCountByUser($User)
+]);
 
-		HTTP::redirect(Application::getEntityURL($User));
-	}
+$MainTemplate = Template\Factory::build('main');
+$MainTemplate->set('TYPE', 'USER');
+$MainTemplate->set('USER', $user_data);
+$MainTemplate->set('HTML', $UserTemplate);
+$MainTemplate->set('HEAD', [
+	'NAME' => $user_data['ATTR']['FULLNAME'],
+	'DESC' => description($user_data['BODY']['HTML'](),
+		Application::get('USER.DESCRIPTION_SIZE')),
+	'PERM' => $user_data['URL'],
+	'OG_IMAGES' => $user_data['FILE']['LIST']
+]);
 
-	catch(User\Exception $Exception) {
-		Application::error404();
-	}
-}
+echo $MainTemplate;
diff --git a/core/namespace/Application.php b/core/namespace/Application.php
index f9a8196..7473e1f 100644
--- a/core/namespace/Application.php
+++ b/core/namespace/Application.php
@@ -6,6 +6,7 @@ class Application {
 	#===============================================================================
 	private static $Database;
 	private static $Language;
+	private static $repositories = [];
 
 	#===============================================================================
 	# Configuration array
@@ -68,6 +69,21 @@ class Application {
 	}
 
 	#===============================================================================
+	# Return singleton repository instance
+	#===============================================================================
+	public function getRepository(string $namespace): Repository {
+		$identifier = strtolower($namespace);
+		$repository = "$namespace\Repository";
+
+		if(!isset(self::$repositories[$identifier])) {
+			$Repository = new $repository(self::getDatabase());
+			self::$repositories[$identifier] = $Repository;
+		}
+
+		return self::$repositories[$identifier];
+	}
+
+	#===============================================================================
 	# Return unique CSRF token for the current session
 	#===============================================================================
 	public static function getSecurityToken(): string {
@@ -142,15 +158,15 @@ class Application {
 	#===============================================================================
 	# Return absolute URL of a specifc entity
 	#===============================================================================
-	public function getEntityURL(Item $Entity) {
+	public function getEntityURL(EntityInterface $Entity) {
 		switch($class = get_class($Entity)) {
-			case 'Page\Item':
+			case 'Page\Entity':
 				$attr = self::get('PAGE.SLUG_URLS') ? 'slug' : 'id';
 				return self::getPageURL($Entity->get($attr).'/');
-			case 'Post\Item':
+			case 'Post\Entity':
 				$attr = self::get('POST.SLUG_URLS') ? 'slug' : 'id';
 				return self::getPostURL($Entity->get($attr).'/');
-			case 'User\Item':
+			case 'User\Entity':
 				$attr = self::get('USER.SLUG_URLS') ? 'slug' : 'id';
 				return self::getUserURL($Entity->get($attr).'/');
 			default:
diff --git a/core/namespace/Attribute.php b/core/namespace/Attribute.php
deleted file mode 100644
index c874a57..0000000
--- a/core/namespace/Attribute.php
+++ /dev/null
@@ -1,84 +0,0 @@
-<?php
-abstract class Attribute {
-
-	#===============================================================================
-	# Set attribute
-	#===============================================================================
-	public function set($attribute, $value) {
-		return $this->{$attribute} = $value;
-	}
-
-	#===============================================================================
-	# Get attribute
-	#===============================================================================
-	public function get($attribute) {
-		return $this->{$attribute} ?? NULL;
-	}
-
-	#===============================================================================
-	# Get all attributes
-	#===============================================================================
-	public function getAll($exclude = []): array {
-		$attributes = get_object_vars($this);
-
-		return array_filter($attributes, function($attribute) use($exclude) {
-			return !in_array($attribute, $exclude);
-		}, ARRAY_FILTER_USE_KEY);
-	}
-
-	#===============================================================================
-	# Get array with not FALSE attributes
-	#===============================================================================
-	protected function getFilteredAttributes(): array {
-		return array_filter(get_object_vars($this), function($value) {
-			return $value !== FALSE;
-		});
-	}
-
-	#===============================================================================
-	# Insert database item
-	#===============================================================================
-	public function insert(\Database $Database): bool {
-		$part[0] = '';
-		$part[1] = '';
-
-		$attributes = $this->getFilteredAttributes();
-
-		foreach($attributes as $column => $value) {
-			$part[0] .= "{$column},";
-			$part[1] .= '?,';
-		}
-
-		$part[0] = rtrim($part[0], ',');
-		$part[1] = rtrim($part[1], ',');
-
-		$Statement = $Database->prepare('INSERT INTO '.static::TABLE." ({$part[0]}) VALUES ({$part[1]})");
-		return $Statement->execute(array_values($attributes));
-	}
-
-	#===============================================================================
-	# Update database item
-	#===============================================================================
-	public function update(\Database $Database): bool {
-		$part = '';
-
-		$attributes = $this->getFilteredAttributes();
-
-		foreach($attributes as $column => $value) {
-			$part .= "{$column} = ?,";
-		}
-
-		$part = rtrim($part, ',');
-
-		$Statement = $Database->prepare('UPDATE '.static::TABLE.' SET '.$part.' WHERE id = '.(int) $this->get('id'));
-		return $Statement->execute(array_values($attributes));
-	}
-
-	#===============================================================================
-	# Delete database item
-	#===============================================================================
-	public function delete(\Database $Database): bool {
-		$Statement = $Database->prepare('DELETE FROM '.static::TABLE.' WHERE id = ?');
-		return $Statement->execute([$this->get('id')]);
-	}
-}
diff --git a/core/namespace/Entity.php b/core/namespace/Entity.php
new file mode 100644
index 0000000..4bedd37
--- /dev/null
+++ b/core/namespace/Entity.php
@@ -0,0 +1,47 @@
+<?php
+abstract class Entity implements EntityInterface {
+	protected $id;
+	protected $time_insert;
+	protected $time_update;
+
+	#===============================================================================
+	# Get attribute
+	#===============================================================================
+	public function get(string $attribute) {
+		return $this->{$attribute} ?? NULL;
+	}
+
+	#===============================================================================
+	# Set attribute
+	#===============================================================================
+	public function set(string $attribute, $value) {
+		return $this->{$attribute} = $value;
+	}
+
+	#===============================================================================
+	# Return ID
+	#===============================================================================
+	final public function getID(): int {
+		return $this->id;
+	}
+
+	#===============================================================================
+	# Get all attributes
+	#===============================================================================
+	public function getAll(array $exclude = []): array {
+		$attributes = get_object_vars($this);
+
+		return array_filter($attributes, function($attribute) use($exclude) {
+			return !in_array($attribute, $exclude);
+		}, ARRAY_FILTER_USE_KEY);
+	}
+
+	#===============================================================================
+	# Get array with all non-false attributes
+	#===============================================================================
+	public function getFilteredAttributes(): array {
+		return array_filter(get_object_vars($this), function($value) {
+			return $value !== FALSE;
+		});
+	}
+}
diff --git a/core/namespace/EntityInterface.php b/core/namespace/EntityInterface.php
new file mode 100644
index 0000000..8eaa089
--- /dev/null
+++ b/core/namespace/EntityInterface.php
@@ -0,0 +1,8 @@
+<?php
+interface EntityInterface {
+	public function get(string $attribute);
+	public function set(string $attribute, $value);
+
+	public function getID(): int;
+	public function getAll(array $exclude = []): array;
+}
diff --git a/core/namespace/Item.php b/core/namespace/Item.php
deleted file mode 100644
index 453a3e6..0000000
--- a/core/namespace/Item.php
+++ /dev/null
@@ -1,98 +0,0 @@
-<?php
-abstract class Item implements ItemInterface {
-	protected $Database   = NULL;
-	protected $Attribute  = NULL;
-	protected $Reflection = NULL;
-
-	#===============================================================================
-	# Abstract item constructor
-	#===============================================================================
-	public final function __construct($itemID, \Database $Database) {
-		$this->Database = $Database;
-
-		$this->Reflection = new ReflectionObject($this);
-
-		$attribute = "{$this->Reflection->getNamespaceName()}\\Attribute";
-		$exception = "{$this->Reflection->getNamespaceName()}\\Exception";
-
-		#===============================================================================
-		# Checking if item in database exists
-		#===============================================================================
-		$Statement = $Database->prepare(sprintf('SELECT * FROM %s WHERE id = ?', $attribute::TABLE));
-		$Statement->execute([$itemID]);
-
-		#===============================================================================
-		# Checking if retrieving data failed
-		#===============================================================================
-		if(!$this->Attribute = $Statement->fetchObject($attribute)) {
-			throw new $exception(sprintf('%s\\Item with ID %s does not exist', $this->Reflection->getNamespaceName(), (int) $itemID));
-		}
-	}
-
-	#===============================================================================
-	# Return attribute by name (short hand wrapper)
-	#===============================================================================
-	public function get($attribute) {
-		return $this->Attribute->get($attribute);
-	}
-
-	#===============================================================================
-	# Return Attribute object
-	#===============================================================================
-	public final function getAttribute(): Attribute {
-		return $this->Attribute;
-	}
-
-	#===============================================================================
-	# Return unique ID
-	#===============================================================================
-	public final function getID(): int {
-		return $this->Attribute->get('id');
-	}
-
-	#===============================================================================
-	# Return previous item ID
-	#===============================================================================
-	public function getPrevID(): int {
-		$execute = 'SELECT id FROM %s WHERE time_insert < ? ORDER BY time_insert DESC LIMIT 1';
-
-		$attribute = "{$this->Reflection->getNamespaceName()}\\Attribute";
-		$Statement = $this->Database->prepare(sprintf($execute, $attribute::TABLE));
-
-		if($Statement->execute([$this->Attribute->get('time_insert')])) {
-			return $Statement->fetchColumn();
-		}
-
-		return 0;
-	}
-
-	#===============================================================================
-	# Return next item ID
-	#===============================================================================
-	public function getNextID(): int {
-		$execute = 'SELECT id FROM %s WHERE time_insert > ? ORDER BY time_insert ASC LIMIT 1';
-
-		$attribute = "{$this->Reflection->getNamespaceName()}\\Attribute";
-		$Statement = $this->Database->prepare(sprintf($execute, $attribute::TABLE));
-
-		if($Statement->execute([$this->Attribute->get('time_insert')])) {
-			return $Statement->fetchColumn();
-		}
-
-		return 0;
-	}
-
-	#===============================================================================
-	# Return unique ID based on specific field comparison with value
-	#===============================================================================
-	public static function getIDByField($field, $value, \Database $Database): int {
-		$attribute = (new ReflectionClass(get_called_class()))->getNamespaceName().'\\Attribute';
-		$Statement = $Database->prepare('SELECT id FROM '.$attribute::TABLE." WHERE {$field} = ?");
-
-		if($Statement->execute([$value])) {
-			return $Statement->fetchColumn();
-		}
-
-		return 0;
-	}
-}
diff --git a/core/namespace/ItemFactory.php b/core/namespace/ItemFactory.php
deleted file mode 100644
index d81ff9f..0000000
--- a/core/namespace/ItemFactory.php
+++ /dev/null
@@ -1,23 +0,0 @@
-<?php
-abstract class ItemFactory extends Factory {
-
-	#===========================================================================
-	# Build instance by ID
-	#===========================================================================
-	public static function build($itemID): Item {
-		if(!$Instance = parent::fetchInstance($itemID)) {
-			$Item = (new ReflectionClass(get_called_class()))->getNamespaceName().'\\Item';
-			$Instance = parent::storeInstance($itemID, new $Item($itemID, \Application::getDatabase()));
-		}
-
-		return $Instance;
-	}
-
-	#===========================================================================
-	# Build instance by slug
-	#===========================================================================
-	public static function buildBySlug($slug): Item {
-		$Item = (new ReflectionClass(get_called_class()))->getNamespaceName().'\\Item';
-		return self::build($Item::getIDByField('slug', $slug, \Application::getDatabase()));
-	}
-}
diff --git a/core/namespace/ItemInterface.php b/core/namespace/ItemInterface.php
deleted file mode 100644
index efee734..0000000
--- a/core/namespace/ItemInterface.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-interface ItemInterface {
-	public function __construct($itemID, \Database $Database);
-}
diff --git a/core/namespace/Page/Attribute.php b/core/namespace/Page/Attribute.php
deleted file mode 100644
index 05eaa33..0000000
--- a/core/namespace/Page/Attribute.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?php
-namespace Page;
-
-class Attribute extends \Attribute {
-
-	#===============================================================================
-	# Pre-Define database table columns
-	#===============================================================================
-	protected $id   = FALSE;
-	protected $user = FALSE;
-	protected $slug = FALSE;
-	protected $name = FALSE;
-	protected $body = FALSE;
-	protected $argv = FALSE;
-	protected $time_insert = FALSE;
-	protected $time_update = FALSE;
-
-	#===============================================================================
-	# Define database table name
-	#===============================================================================
-	const TABLE = 'page';
-}
diff --git a/core/namespace/Page/Entity.php b/core/namespace/Page/Entity.php
new file mode 100644
index 0000000..6ca5979
--- /dev/null
+++ b/core/namespace/Page/Entity.php
@@ -0,0 +1,13 @@
+<?php
+namespace Page;
+
+class Entity extends \Entity {
+	protected $id   = FALSE;
+	protected $user = FALSE;
+	protected $slug = FALSE;
+	protected $name = FALSE;
+	protected $body = FALSE;
+	protected $argv = FALSE;
+	protected $time_insert = FALSE;
+	protected $time_update = FALSE;
+}
diff --git a/core/namespace/Page/Exception.php b/core/namespace/Page/Exception.php
deleted file mode 100644
index c41bddc..0000000
--- a/core/namespace/Page/Exception.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-namespace Page;
-
-class Exception extends \Exception {}
diff --git a/core/namespace/Page/Factory.php b/core/namespace/Page/Factory.php
deleted file mode 100644
index 2fcc361..0000000
--- a/core/namespace/Page/Factory.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-namespace Page;
-
-class Factory extends \ItemFactory {}
diff --git a/core/namespace/Page/Item.php b/core/namespace/Page/Item.php
deleted file mode 100644
index cbc99e6..0000000
--- a/core/namespace/Page/Item.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-namespace Page;
-
-class Item extends \Item {
-	const CONFIGURATION = 'PAGE';
-
-	#===============================================================================
-	# Return unique page IDs for search results
-	#===============================================================================
-	public static function getSearchResultIDs($search, \Database $Database): array {
-		$Statement = $Database->prepare(sprintf("SELECT id FROM %s WHERE
-			MATCH(name, body) AGAINST(? IN BOOLEAN MODE) LIMIT 20", Attribute::TABLE));
-
-		if($Statement->execute([$search])) {
-			return $Statement->fetchAll($Database::FETCH_COLUMN);
-		}
-
-		return [];
-	}
-}
diff --git a/core/namespace/Page/Repository.php b/core/namespace/Page/Repository.php
new file mode 100644
index 0000000..b76ef85
--- /dev/null
+++ b/core/namespace/Page/Repository.php
@@ -0,0 +1,17 @@
+<?php
+namespace Page;
+
+class Repository extends \Repository {
+	public static function getTableName(): string { return 'page'; }
+	public static function getClassName(): string { return 'Page\Entity'; }
+
+	public function getCountByUser(\User\Entity $User): int {
+		$query = 'SELECT COUNT(id) FROM %s WHERE user = ?';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute([$User->getID()]);
+
+		return $Statement->fetchColumn();
+	}
+}
diff --git a/core/namespace/Post/Attribute.php b/core/namespace/Post/Attribute.php
deleted file mode 100644
index 20aafae..0000000
--- a/core/namespace/Post/Attribute.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?php
-namespace Post;
-
-class Attribute extends \Attribute {
-
-	#===============================================================================
-	# Pre-Define database table columns
-	#===============================================================================
-	protected $id   = FALSE;
-	protected $user = FALSE;
-	protected $slug = FALSE;
-	protected $name = FALSE;
-	protected $body = FALSE;
-	protected $argv = FALSE;
-	protected $time_insert = FALSE;
-	protected $time_update = FALSE;
-
-	#===============================================================================
-	# Define database table name
-	#===============================================================================
-	const TABLE = 'post';
-}
diff --git a/core/namespace/Post/Entity.php b/core/namespace/Post/Entity.php
new file mode 100644
index 0000000..399f5bb
--- /dev/null
+++ b/core/namespace/Post/Entity.php
@@ -0,0 +1,13 @@
+<?php
+namespace Post;
+
+class Entity extends \Entity {
+	protected $id   = FALSE;
+	protected $user = FALSE;
+	protected $slug = FALSE;
+	protected $name = FALSE;
+	protected $body = FALSE;
+	protected $argv = FALSE;
+	protected $time_insert = FALSE;
+	protected $time_update = FALSE;
+}
diff --git a/core/namespace/Post/Exception.php b/core/namespace/Post/Exception.php
deleted file mode 100644
index 29b9345..0000000
--- a/core/namespace/Post/Exception.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-namespace Post;
-
-class Exception extends \Exception {}
diff --git a/core/namespace/Post/Factory.php b/core/namespace/Post/Factory.php
deleted file mode 100644
index 20b29cc..0000000
--- a/core/namespace/Post/Factory.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-namespace Post;
-
-class Factory extends \ItemFactory {}
diff --git a/core/namespace/Post/Item.php b/core/namespace/Post/Item.php
deleted file mode 100644
index e8b4615..0000000
--- a/core/namespace/Post/Item.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-namespace Post;
-
-class Item extends \Item {
-	const CONFIGURATION = 'POST';
-
-	#===============================================================================
-	# Return unique post IDs for search results
-	#===============================================================================
-	public static function getSearchResultIDs($search, array $date, \Database $Database): array {
-		$D = ($D = intval($date[0])) !== 0 ? $D : 'NULL';
-		$M = ($M = intval($date[1])) !== 0 ? $M : 'NULL';
-		$Y = ($Y = intval($date[2])) !== 0 ? $Y : 'NULL';
-
-		$Statement = $Database->prepare(sprintf("SELECT id FROM %s WHERE 
-			({$Y} IS NULL OR YEAR(time_insert) = {$Y})  AND
-			({$M} IS NULL OR MONTH(time_insert) = {$M}) AND
-			({$D} IS NULL OR DAY(time_insert) = {$D})   AND
-			MATCH(name, body) AGAINST(? IN BOOLEAN MODE) LIMIT 20", Attribute::TABLE));
-
-		if($Statement->execute([$search])) {
-			return $Statement->fetchAll($Database::FETCH_COLUMN);
-		}
-
-		return [];
-	}
-}
diff --git a/core/namespace/Post/Repository.php b/core/namespace/Post/Repository.php
new file mode 100644
index 0000000..5a3d834
--- /dev/null
+++ b/core/namespace/Post/Repository.php
@@ -0,0 +1,17 @@
+<?php
+namespace Post;
+
+class Repository extends \Repository {
+	public static function getTableName(): string { return 'post'; }
+	public static function getClassName(): string { return 'Post\Entity'; }
+
+	public function getCountByUser(\User\Entity $User): int {
+		$query = 'SELECT COUNT(id) FROM %s WHERE user = ?';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute([$User->getID()]);
+
+		return $Statement->fetchColumn();
+	}
+}
diff --git a/core/namespace/Repository.php b/core/namespace/Repository.php
new file mode 100644
index 0000000..2c238b8
--- /dev/null
+++ b/core/namespace/Repository.php
@@ -0,0 +1,323 @@
+<?php
+abstract class Repository {
+	protected $Database;
+	protected $entities = [];
+
+	abstract public static function getTableName(): string;
+	abstract public static function getClassName(): string;
+
+	public function __construct(Database $Database) {
+		$this->Database = $Database;
+	}
+
+	#===============================================================================
+	# Adds an entity to the runtime cache
+	#===============================================================================
+	protected function storeInstance(int $identifier, EntityInterface $Entity) {
+		return $this->entities[$identifier] = $Entity;
+	}
+
+	#===============================================================================
+	# Adds an array of entities to the runtime cache
+	#===============================================================================
+	protected function storeMultipleInstances(array $entities) {
+		foreach($entities as $Entity) {
+			$this->storeInstance($Entity->getID(), $Entity);
+		}
+
+		return $entities;
+	}
+
+	#===============================================================================
+	# Gets an entity from the runtime cache
+	#===============================================================================
+	protected function fetchInstance(int $identifier) {
+		return $this->entities[$identifier] ?? FALSE;
+	}
+
+	#===============================================================================
+	# Removes an entity from the runtime cache
+	#===============================================================================
+	protected function removeInstance(int $identifier) {
+		if(isset($this->cache[$identifier])) {
+			unset($this->cache[$identifier]);
+		}
+	}
+
+	#===========================================================================
+	# Insert entity
+	#===========================================================================
+	public function insert(EntityInterface $Entity): bool {
+		$attributes = $Entity->getFilteredAttributes();
+
+		foreach($attributes as $field => $value) {
+			$fields[] = $field;
+			$values[] = '?';
+		}
+
+		$fields = implode(', ', $fields ?? []);
+		$values = implode(', ', $values ?? []);
+
+		$query = 'INSERT INTO %s (%s) VALUES(%s)';
+		$query = sprintf($query, static::getTableName(), $fields, $values);
+
+		$Statement = $this->Database->prepare($query);
+		return $Statement->execute(array_values($attributes));
+	}
+
+	#===========================================================================
+	# Update entity
+	#===========================================================================
+	public function update(EntityInterface $Entity): bool {
+		$attributes = $Entity->getFilteredAttributes();
+
+		foreach($attributes as $field => $value) {
+			$params[] = "$field = ?";
+		}
+
+		$params = implode(', ', $params ?? []);
+
+		$query = 'UPDATE %s SET %s WHERE id = '.intval($Entity->getID());
+		$query = sprintf($query, static::getTableName(), $params);
+
+		$Statement = $this->Database->prepare($query);
+		return $Statement->execute(array_values($attributes));
+	}
+
+	#===========================================================================
+	# Delete entity
+	#===========================================================================
+	public function delete(EntityInterface $Entity): bool {
+		$query = 'DELETE FROM %s WHERE id = ?';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->prepare($query);
+		return $Statement->execute([$Entity->getID()]);
+	}
+
+	#===========================================================================
+	# Find entity based on primary key
+	#===========================================================================
+	public function find(int $id): ?EntityInterface {
+		if($Entity = $this->fetchInstance($id)) {
+			return $Entity;
+		}
+
+		return $this->findBy('id', $id);
+	}
+
+	#===============================================================================
+	# Find entity based on specific field comparison
+	#===============================================================================
+	public function findBy(string $field, $value): ?EntityInterface {
+		$query = 'SELECT * FROM %s WHERE %s = ?';
+		$query = sprintf($query, static::getTableName(), $field);
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute([$value]);
+
+		if($Entity = $Statement->fetchObject(static::getClassName())) {
+			$this->storeInstance($Entity->getID(), $Entity);
+			return $Entity;
+		}
+
+		return NULL;
+	}
+
+	#===============================================================================
+	# Find previous entitiy
+	#===============================================================================
+	public function findPrev(EntityInterface $Entity): ?EntityInterface {
+		$query = 'SELECT * FROM %s WHERE time_insert < ? ORDER BY time_insert DESC LIMIT 1';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute([$Entity->get('time_insert')]);
+
+		if($Entity = $Statement->fetchObject(static::getClassName())) {
+			$this->storeInstance($Entity->getID(), $Entity);
+			return $Entity;
+		}
+
+		return NULL;
+	}
+
+	#===============================================================================
+	# Find next entity
+	#===============================================================================
+	public function findNext(EntityInterface $Entity): ?EntityInterface {
+		$query = 'SELECT * FROM %s WHERE time_insert > ? ORDER BY time_insert ASC LIMIT 1';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute([$Entity->get('time_insert')]);
+
+		if($Entity = $Statement->fetchObject(static::getClassName())) {
+			$this->storeInstance($Entity->getID(), $Entity);
+			return $Entity;
+		}
+
+		return NULL;
+	}
+
+	#===========================================================================
+	# Find last (which means the newest) entity
+	#===========================================================================
+	public function getLast(): ?EntityInterface {
+		$query = 'SELECT * FROM %s ORDER BY time_insert DESC LIMIT 1';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->query($query);
+
+		if($Entity = $Statement->fetchObject(static::getClassName())) {
+			$this->storeInstance($Entity->getID(), $Entity);
+			return $Entity;
+		}
+
+		return NULL;
+	}
+
+	#===========================================================================
+	# Get entity count
+	#===========================================================================
+	public function getCount(): int {
+		$query = 'SELECT COUNT(id) FROM %s';
+		$query = sprintf($query, static::getTableName());
+
+		return $this->Database->query($query)->fetchColumn();
+	}
+
+	#===========================================================================
+	# Get paginated entity list
+	#===========================================================================
+	public function getPaginated(string $order, int $limit, int $offset = 0): array {
+		return $this->getAll([], $order, "$offset,$limit");
+	}
+
+	#===========================================================================
+	# Get all entities
+	#===========================================================================
+	public function getAll(array $filter = [], string $order = null, string $limit = null): array {
+		$select = 'SELECT * FROM '.static::getTableName();
+		$wheres = [];
+		$params = [];
+
+		if(!empty($filter)) {
+			foreach($filter as $column => $value) {
+				$wheres[] = "$column = ?";
+				$params[] = $value;
+			}
+
+			$where = 'WHERE '.implode(' AND ', $wheres);
+		}
+
+		if($order) {
+			$order = "ORDER BY $order";
+		}
+
+		if($limit) {
+			$limit = "LIMIT $limit";
+		}
+
+		$query = "$select %s %s %s";
+		$query = sprintf($query, $where ?? '', $order ?? '', $limit ?? '');
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute($params);
+
+		if($entities = $Statement->fetchAll($this->Database::FETCH_CLASS, static::getClassName())) {
+			$this->storeMultipleInstances($entities);
+			return $entities;
+		}
+
+		return [];
+	}
+
+	#===============================================================================
+	# Get entities based on search query
+	#===============================================================================
+	public function search(string $search, array $filter = []): array {
+		if($search === '*') {
+			return $this->getAll([], NULL, 20);
+		}
+
+		if(strlen($filter['year'] ?? '') !== 0) {
+			$extend[] = 'YEAR(time_insert) = ? AND';
+			$params[] = $filter['year'];
+		}
+
+		if(strlen($filter['month'] ?? '') !== 0) {
+			$extend[] = 'MONTH(time_insert) = ? AND';
+			$params[] = $filter['month'];
+		}
+
+		if(strlen($filter['day'] ?? '') !== 0) {
+			$extend[] = 'DAY(time_insert) = ? AND';
+			$params[] = $filter['day'];
+		}
+
+		$dateparts = implode(' ', $extend ?? []);
+
+		$query = 'SELECT * FROM %s WHERE %s MATCH(name, body)
+			AGAINST(? IN BOOLEAN MODE) LIMIT 20';
+		$query = sprintf($query, static::getTableName(), $dateparts);
+
+		$Statement = $this->Database->prepare($query);
+		$Statement->execute(array_merge($params ?? [], [$search]));
+
+		if($entities = $Statement->fetchAll($this->Database::FETCH_CLASS, static::getClassName())) {
+			$this->storeMultipleInstances($entities);
+			return $entities;
+		}
+
+		return [];
+	}
+
+	#===============================================================================
+	# Get a list of distinct days
+	#===============================================================================
+	public function getDistinctDays(): array {
+		$query = 'SELECT DISTINCT DAY(time_insert) AS d FROM %s ORDER BY d';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->query($query);
+
+		if($result = $Statement->fetchAll($this->Database::FETCH_COLUMN)) {
+			return $result;
+		}
+
+		return [];
+	}
+
+	#===============================================================================
+	# Get a list of distinct months
+	#===============================================================================
+	public function getDistinctMonths(): array {
+		$query = 'SELECT DISTINCT MONTH(time_insert) AS m FROM %s ORDER BY m';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->query($query);
+
+		if($result = $Statement->fetchAll($this->Database::FETCH_COLUMN)) {
+			return $result;
+		}
+
+		return [];
+	}
+
+	#===============================================================================
+	# Get a list of distinct years
+	#===============================================================================
+	public function getDistinctYears(): array {
+		$query = 'SELECT DISTINCT YEAR(time_insert) AS y FROM %s ORDER BY y';
+		$query = sprintf($query, static::getTableName());
+
+		$Statement = $this->Database->query($query);
+
+		if($result = $Statement->fetchAll($this->Database::FETCH_COLUMN)) {
+			return $result;
+		}
+
+		return [];
+	}
+}
diff --git a/core/namespace/User/Attribute.php b/core/namespace/User/Attribute.php
deleted file mode 100644
index ccd31b5..0000000
--- a/core/namespace/User/Attribute.php
+++ /dev/null
@@ -1,24 +0,0 @@
-<?php
-namespace User;
-
-class Attribute extends \Attribute {
-
-	#===============================================================================
-	# Pre-Define database table columns
-	#===============================================================================
-	protected $id       = FALSE;
-	protected $slug     = FALSE;
-	protected $username = FALSE;
-	protected $password = FALSE;
-	protected $fullname = FALSE;
-	protected $mailaddr = FALSE;
-	protected $body     = FALSE;
-	protected $argv     = FALSE;
-	protected $time_insert = FALSE;
-	protected $time_update = FALSE;
-
-	#===============================================================================
-	# Define database table name
-	#===============================================================================
-	const TABLE = 'user';
-}
diff --git a/core/namespace/User/Entity.php b/core/namespace/User/Entity.php
new file mode 100644
index 0000000..fdfaf9e
--- /dev/null
+++ b/core/namespace/User/Entity.php
@@ -0,0 +1,15 @@
+<?php
+namespace User;
+
+class Entity extends \Entity {
+	protected $id       = FALSE;
+	protected $slug     = FALSE;
+	protected $username = FALSE;
+	protected $password = FALSE;
+	protected $fullname = FALSE;
+	protected $mailaddr = FALSE;
+	protected $body     = FALSE;
+	protected $argv     = FALSE;
+	protected $time_insert = FALSE;
+	protected $time_update = FALSE;
+}
diff --git a/core/namespace/User/Exception.php b/core/namespace/User/Exception.php
deleted file mode 100644
index fdbe733..0000000
--- a/core/namespace/User/Exception.php
+++ /dev/null
@@ -1,4 +0,0 @@
-<?php
-namespace User;
-
-class Exception extends \Exception {}
diff --git a/core/namespace/User/Factory.php b/core/namespace/User/Factory.php
deleted file mode 100644
index 81930e6..0000000
--- a/core/namespace/User/Factory.php
+++ /dev/null
@@ -1,8 +0,0 @@
-<?php
-namespace User;
-
-class Factory extends \ItemFactory {
-	public static function buildByUsername($username): \Item {
-		return self::build(Item::getIDByField('username', $username, \Application::getDatabase()));
-	}
-}
diff --git a/core/namespace/User/Item.php b/core/namespace/User/Item.php
deleted file mode 100644
index 5039287..0000000
--- a/core/namespace/User/Item.php
+++ /dev/null
@@ -1,6 +0,0 @@
-<?php
-namespace User;
-
-class Item extends \Item {
-	const CONFIGURATION = 'USER';
-}
diff --git a/core/namespace/User/Repository.php b/core/namespace/User/Repository.php
new file mode 100644
index 0000000..59205b3
--- /dev/null
+++ b/core/namespace/User/Repository.php
@@ -0,0 +1,7 @@
+<?php
+namespace User;
+
+class Repository extends \Repository {
+	public static function getTableName(): string { return 'user'; }
+	public static function getClassName(): string { return 'User\Entity'; }
+}