First draft for plugins system

6 files changed, 262 insertions, 57 deletions

diff --git a/app/Core/PluginBase.php b/app/Core/PluginBase.php
new file mode 100644
index 00000000..9c3d6e32
--- /dev/null
+++ b/app/Core/PluginBase.php
@@ -0,0 +1,31 @@
+<?php
+
+namespace Core;
+
+/**
+ * Plugin Base class
+ *
+ * @package  core
+ * @author   Frederic Guillot
+ */
+abstract class PluginBase extends Base
+{
+    /**
+     * Method called for each request
+     *
+     * @abstract
+     * @access public
+     */
+    abstract public function initialize();
+
+    /**
+     * Returns all classes that needs to be stored in the DI container
+     *
+     * @access public
+     * @return array
+     */
+    public function getClasses()
+    {
+        return array();
+    }
+}
diff --git a/app/Core/PluginLoader.php b/app/Core/PluginLoader.php
new file mode 100644
index 00000000..6030ded4
--- /dev/null
+++ b/app/Core/PluginLoader.php
@@ -0,0 +1,144 @@
+<?php
+
+namespace Core;
+
+use DirectoryIterator;
+use PDOException;
+
+/**
+ * Plugin Loader
+ *
+ * @package  core
+ * @author   Frederic Guillot
+ */
+class PluginLoader extends Base
+{
+    /**
+     * Schema version table for plugins
+     *
+     * @var string
+     */
+    const TABLE_SCHEMA = 'plugin_schema_versions';
+
+    /**
+     * Plugin folder
+     *
+     * @var string
+     */
+    const PATH = __DIR__.'/../../plugins';
+
+    /**
+     * Scan plugin folder and load plugins
+     *
+     * @access public
+     */
+    public function scan()
+    {
+        if (file_exists(self::PATH)) {
+            $dir = new DirectoryIterator(self::PATH);
+
+            foreach ($dir as $fileinfo) {
+                if (! $fileinfo->isDot() && $fileinfo->isDir()) {
+                    $plugin = $fileinfo->getFilename();
+                    $this->loadSchema($plugin);
+                    $this->load($plugin);
+                }
+            }
+        }
+    }
+
+    /**
+     * Load plugin
+     *
+     * @access public
+     */
+    public function load($plugin)
+    {
+        $class = '\Plugin\\'.$plugin.'\\Plugin';
+        $instance = new $class($this->container);
+
+        Tool::buildDic($this->container, $instance->getClasses());
+
+        $instance->initialize();
+    }
+
+    /**
+     * Load plugin schema
+     *
+     * @access public
+     * @param  string  $plugin
+     */
+    public function loadSchema($plugin)
+    {
+        $filename = __DIR__.'/../../plugins/'.$plugin.'/Schema/'.ucfirst(DB_DRIVER).'.php';
+
+        if (file_exists($filename)) {
+            require($filename);
+            $this->migrateSchema($plugin);
+        }
+    }
+
+    /**
+     * Execute plugin schema migrations
+     *
+     * @access public
+     * @param  string  $plugin
+     */
+    public function migrateSchema($plugin)
+    {
+        $last_version = constant('\Plugin\\'.$plugin.'\Schema\VERSION');
+        $current_version = $this->getSchemaVersion($plugin);
+
+        try {
+
+            $this->db->startTransaction();
+            $this->db->getDriver()->disableForeignKeys();
+
+            for ($i = $current_version + 1; $i <= $last_version; $i++) {
+                $function_name = '\Plugin\\'.$plugin.'\Schema\version_'.$i;
+
+                if (function_exists($function_name)) {
+                    call_user_func($function_name, $this->db->getConnection());
+                }
+            }
+
+            $this->db->getDriver()->enableForeignKeys();
+            $this->db->closeTransaction();
+            $this->setSchemaVersion($plugin, $i - 1);
+        }
+        catch (PDOException $e) {
+            $this->db->cancelTransaction();
+            $this->db->getDriver()->enableForeignKeys();
+            die('Unable to migrate schema for the plugin: '.$plugin.' => '.$e->getMessage());
+        }
+    }
+
+    /**
+     * Get current plugin schema version
+     *
+     * @access public
+     * @param  string  $plugin
+     * @return integer
+     */
+    public function getSchemaVersion($plugin)
+    {
+        return (int) $this->db->table(self::TABLE_SCHEMA)->eq('plugin', strtolower($plugin))->findOneColumn('version');
+    }
+
+    /**
+     * Save last plugin schema version
+     *
+     * @access public
+     * @param  string   $plugin
+     * @param  integer  $version
+     * @return boolean
+     */
+    public function setSchemaVersion($plugin, $version)
+    {
+        $dictionary = array(
+            strtolower($plugin) => $version
+        );
+
+        return $this->db->getDriver()->upsert(self::TABLE_SCHEMA, 'plugin', 'version', $dictionary);
+    }
+}
diff --git a/app/Core/Router.php b/app/Core/Router.php
index 6e7576d6..36bbfd55 100644
--- a/app/Core/Router.php
+++ b/app/Core/Router.php
@@ -213,49 +213,17 @@ class Router extends Base
         if (! empty($_GET['controller']) && ! empty($_GET['action'])) {
             $controller = $this->sanitize($_GET['controller'], 'app');
             $action = $this->sanitize($_GET['action'], 'index');
+            $plugin = ! empty($_GET['plugin']) ? $this->sanitize($_GET['plugin'], '') : '';
         }
         else {
-            list($controller, $action) = $this->findRoute($this->getPath($uri, $query_string));
+            list($controller, $action) = $this->findRoute($this->getPath($uri, $query_string)); // TODO: add plugin for routes
+            $plugin = '';
         }
 
-        return $this->load(
-            __DIR__.'/../Controller/'.ucfirst($controller).'.php',
-            $controller,
-            '\Controller\\'.ucfirst($controller),
-            $action
-        );
-    }
-
-    /**
-     * Load a controller and execute the action
-     *
-     * @access private
-     * @param  string $filename
-     * @param  string $controller
-     * @param  string $class
-     * @param  string $method
-     * @return bool
-     */
-    private function load($filename, $controller, $class, $method)
-    {
-        if (file_exists($filename)) {
-
-            require $filename;
-
-            if (! method_exists($class, $method)) {
-                return false;
-            }
-
-            $this->action = $method;
-            $this->controller = $controller;
-
-            $instance = new $class($this->container);
-            $instance->beforeAction($controller, $method);
-            $instance->$method();
-
-            return true;
-        }
+        $class = empty($plugin) ? '\Controller\\'.ucfirst($controller) : '\Plugin\\'.ucfirst($plugin).'\Controller\\'.ucfirst($controller);
 
-        return false;
+        $instance = new $class($this->container);
+        $instance->beforeAction($controller, $action);
+        $instance->$action();
     }
 }
diff --git a/app/Core/Template.php b/app/Core/Template.php
index ba869ee6..b75f7da1 100644
--- a/app/Core/Template.php
+++ b/app/Core/Template.php
@@ -13,11 +13,12 @@ use LogicException;
 class Template extends Helper
 {
     /**
-     * Template path
+     * List of template overrides
      *
-     * @var string
+     * @access private
+     * @var array
      */
-    const PATH = 'app/Template/';
+    private $overrides = array();
 
     /**
      * Render a template
@@ -33,16 +34,10 @@ class Template extends Helper
      */
     public function render($__template_name, array $__template_args = array())
     {
-        $__template_file = self::PATH.$__template_name.'.php';
-
-        if (! file_exists($__template_file)) {
-            throw new LogicException('Unable to load the template: "'.$__template_name.'"');
-        }
-
         extract($__template_args);
 
         ob_start();
-        include $__template_file;
+        include $this->getTemplateFile($__template_name);
         return ob_get_clean();
     }
 
@@ -62,4 +57,41 @@ class Template extends Helper
             $template_args + array('content_for_layout' => $this->render($template_name, $template_args))
         );
     }
+
+    /**
+     * Define a new template override
+     *
+     * @access public
+     * @param  string  $original_template
+     * @param  string  $new_template
+     */
+    public function setTemplateOverride($original_template, $new_template)
+    {
+        $this->overrides[$original_template] = $new_template;
+    }
+
+    /**
+     * Find template filename
+     *
+     * Core template name: 'task/show'
+     * Plugin template name: 'myplugin:task/show'
+     *
+     * @access public
+     * @param  string  $template_name
+     * @return string
+     */
+    public function getTemplateFile($template_name)
+    {
+        $template_name = isset($this->overrides[$template_name]) ? $this->overrides[$template_name] : $template_name;
+
+        if (strpos($template_name, ':') !== false) {
+            list($plugin, $template) = explode(':', $template_name);
+            $path = __DIR__.'/../../plugins/'.ucfirst($plugin).'/Template/'.$template.'.php';
+        }
+        else {
+            $path = __DIR__.'/../Template/'.$template_name.'.php';
+        }
+
+        return $path;
+    }
 }
diff --git a/app/Core/Tool.php b/app/Core/Tool.php
index 84e42ba8..7939a80e 100644
--- a/app/Core/Tool.php
+++ b/app/Core/Tool.php
@@ -2,6 +2,8 @@
 
 namespace Core;
 
+use Pimple\Container;
+
 /**
  * Tool class
  *
@@ -23,7 +25,6 @@ class Tool
         $fp = fopen($filename, 'w');
 
         if (is_resource($fp)) {
-
             foreach ($rows as $fields) {
                 fputcsv($fp, $fields);
             }
@@ -51,4 +52,24 @@ class Tool
 
         return $identifier;
     }
+
+    /**
+     * Build dependency injection container from an array
+     *
+     * @static
+     * @access public
+     * @param  Container  $container
+     * @param  array      $namespaces
+     */
+    public static function buildDIC(Container $container, array $namespaces)
+    {
+        foreach ($namespaces as $namespace => $classes) {
+            foreach ($classes as $name) {
+                $class = '\\'.$namespace.'\\'.$name;
+                $container[lcfirst($name)] = function ($c) use ($class) {
+                    return new $class($c);
+                };
+            }
+        }
+    }
 }
diff --git a/app/Core/Translator.php b/app/Core/Translator.php
index e3d19692..e9aa1f3f 100644
--- a/app/Core/Translator.php
+++ b/app/Core/Translator.php
@@ -15,7 +15,7 @@ class Translator
      *
      * @var string
      */
-    const PATH = 'app/Locale/';
+    const PATH = 'app/Locale';
 
     /**
      * Locale
@@ -196,18 +196,27 @@ class Translator
      * @static
      * @access public
      * @param  string   $language   Locale code: fr_FR
+     * @param  string   $path       Locale folder
      */
-    public static function load($language)
+    public static function load($language, $path = self::PATH)
     {
         setlocale(LC_TIME, $language.'.UTF-8', $language);
 
-        $filename = self::PATH.$language.DIRECTORY_SEPARATOR.'translations.php';
+        $filename = $path.DIRECTORY_SEPARATOR.$language.DIRECTORY_SEPARATOR.'translations.php';
 
         if (file_exists($filename)) {
-            self::$locales = require $filename;
-        }
-        else {
-            self::$locales = array();
+            self::$locales = array_merge(self::$locales, require($filename));
         }
     }
+
+    /**
+     * Clear locales stored in memory
+     *
+     * @static
+     * @access public
+     */
+    public static function unload()
+    {
+        self::$locales = array();
+    }
 }