APICHANGE: use static $modelClass for DMS, instead of pass through a classname when getting a DMS instance.

FEATURE: add the "Documents" tab to page CMS fields, make the displayed fields customisable by DMSDocument subclass

code/DMS.php

@@ -7,19 +7,22 @@ class DMS implements DMSInterface {
 	//The number should be a multiple of 10
 	static $dmsFolderSize = 1000;
 	static $dmsPath;    //DMS path set on creation
-	protected $modelClass;
+	static $modelClass = 'DMSDocument';
+	
+	static function set_model_class($className){
+		self::$modelClass = $className;
+	}
 
 	/**
 	 * Factory method that returns an instance of the DMS. This could be any class that implements the DMSInterface.
 	 * @static
 	 * @return DMSInterface An instance of the Document Management System
 	 */
-	static function getDMSInstance($className="DMSDocument") {
+	static function getDMSInstance() {
 		self::$dmsPath = BASE_PATH . DIRECTORY_SEPARATOR . self::$dmsFolder;
 
 		$dms = new DMS();
 		self::createStorageFolder(self::$dmsPath);
-		$dms->modelClass = $className;
 		return $dms;
 	}
 
@@ -44,7 +47,7 @@ class DMS implements DMSInterface {
 		$filePath = self::transformFileToFilePath($file);
 		
 		//create a new document and get its ID
-		$modelClass = $this->modelClass;
+		$modelClass = self::$modelClass;
 		$doc = new $modelClass();
 		$doc->write();
 		$doc->storeDocument($filePath);

code/DMSDocument.php

@@ -12,6 +12,13 @@ class DMSDocument extends DataObject implements DMSDocumentInterface {
 		'Pages' => 'SiteTree',
 		'Tags' => 'DMSTag'
 	);
+	
+	static $display_fields = array(
+		'ID'=>'ID',
+		'Title'=>'Title',
+		'Filename'=>'Filename',
+		'LastChanged'=>'LastChanged'
+	);
 
 	/**
 	 * Associates this document with a Page. This method does nothing if the association already exists.

code/DMSSiteTreeExtension.php

@@ -4,4 +4,20 @@ class DMSSiteTreeExtension extends DataExtension {
 	static $belongs_many_many = array(
 		'Documents' => 'DMSDocument'
 	);
+	
+	function updateCMSFields(&$fields){
+		$documentsListConfig = GridFieldConfig_RecordEditor::create();
+		$modelClass = DMS::$modelClass;
+		$documentsListConfig->getComponentByType('GridFieldDataColumns')->setDisplayFields($modelClass::$display_fields);
+		
+		$fields->addFieldToTab(
+			'Root.Documents', 
+			GridField::create(
+				'Documents', 
+				false, 
+				$this->owner->Documents(),
+				$documentsListConfig
+			)
+		);
+	}
 }