minor: add a file store class to handle storing and loading of files to the disk

main/inc/lib/file_store.class.php

@@ -0,0 +1,95 @@
+<?php
+
+/**
+ *
+ * @copyright (c) 2012 University of Geneva
+ * @license GNU General Public License - http://www.gnu.org/copyleft/gpl.html
+ * @author Laurent Opprecht <laurent@opprecht.info>
+ */
+class FileStore
+{
+
+    /**
+     *
+     * @param int $c_id
+     * @param string $sub_path 
+
+     * @return FileStore 
+     */
+    static function course($c_id, $sub_path = '') 
+    { 
+        
+        $sys_path = api_get_path(SYS_COURSE_PATH);
+        $course = api_get_course_info_by_id($c_id);
+        $course_path = $course['path'];
+        $path = $sys_path . $course_path . $sub_path;
+        if (!is_dir($path)) {
+            $mode = api_get_permissions_for_new_directories();
+            $success = mkdir($path, $mode, true);
+            if (!$success) {
+                return false;
+            }
+        }
+        return new self($path);
+    }
+
+    protected $root = '';
+
+    public function __construct($root)
+    {
+        $root = ltrim($root, '/');
+        $root .= '/';
+        $this->root = $root;
+    }
+
+    public function root()
+    {
+        return $this->root;
+    }
+
+    function accept($filename)
+    {
+        return (bool) filter_extension($filename);
+    }
+
+    function add($path)
+    {
+        $root = $this->root();
+        $id = $this->new_id();
+
+        $new_path = "$root/$id";
+        $success = @move_uploaded_file($path, $new_path);
+        return $success ? $id : false;
+    }
+    
+    function remove($path){
+        
+        $root = $this->root();
+        $full_path = "$root/$path";
+        if(is_file($full_path)){
+            $result = unlink($full_path);
+            return $result;
+        }
+        return  false;
+    }
+
+    function get($id)
+    {
+        $root = $this->root();
+        $result = "$root/$id";
+        return $result;
+    }
+
+    function new_id()
+    {
+        $root = $this->root();
+        $id = uniqid('');
+        $path = "$root/$id";
+        while (file_exists($path)) {
+            $id = uniqid('');
+            $path = "$root/$id";
+        }
+        return $id;
+    }
+
+}