<?php

namespace SilverStripe\CMS\Controllers;

use SearchContext;
use SearchFilter;
use SilverStripe\Filesystem\Storage\AssetNameGenerator;
use SilverStripe\ORM\ArrayList;
use SilverStripe\ORM\DataList;
use SilverStripe\ORM\FieldType\DBHTMLText;
use SilverStripe\ORM\Versioning\Versioned;
use SilverStripe\ORM\DataObject;
use SilverStripe\ORM\SS_List;
use SilverStripe\Security\Security;
use SilverStripe\Security\PermissionProvider;
use SilverStripe\Admin\CMSBatchAction;
use SilverStripe\Admin\CMSBatchActionHandler;
use SilverStripe\Admin\LeftAndMain;
use Session;
use Requirements;
use File;
use DateField;
use HiddenField;
use GridFieldConfig;
use GridFieldToolbarHeader;
use GridFieldSortableHeader;
use GridFieldFilterHeader;
use GridFieldDataColumns;
use GridFieldPaginator;
use GridFieldEditButton;
use GridFieldDeleteAction;
use GridFieldDetailForm;
use GridFieldLevelup;
use GridField;
use Controller;
use LiteralField;
use SS_HTTPRequest;
use TabSet;
use Tab;
use CompositeField;
use UploadField;
use FormField;
use SS_HTTPResponse;
use Convert;
use SS_HTTPResponse_Exception;
use HeaderField;
use FieldGroup;
use DropdownField;
use CheckboxField;
use FieldList;
use FormAction;
use Object;
use Form;
use TextField;
use Folder;
use Injector;
use Director;
use ArrayData;


/**
 * AssetAdmin is the 'file store' section of the CMS.
 * It provides an interface for manipulating the File and Folder objects in the system.
 *
 * @package cms
 * @subpackage assets
 */
class AssetAdmin extends LeftAndMain implements PermissionProvider{

	private static $url_segment = 'assets';

	private static $url_rule = '/$Action/$ID';

	private static $menu_title = 'Files';

	private static $tree_class = 'Folder';

	/**
	 * Amount of results showing on a single page.
	 *
	 * @config
	 * @var int
	 */
	private static $page_length = 15;

	/**
	 * @config
	 * @see Upload->allowedMaxFileSize
	 * @var int
	 */
	private static $allowed_max_file_size;

	private static $allowed_actions = array(
		'addfolder',
		'delete',
		'AddForm',
		'SearchForm',
		'getsubtree'
	);

	private static $required_permission_codes = 'CMS_ACCESS_AssetAdmin';

	/**
	 * Return fake-ID "root" if no ID is found (needed to upload files into the root-folder)
	 */
	public function currentPageID() {
		if(is_numeric($this->getRequest()->requestVar('ID')))	{
			return $this->getRequest()->requestVar('ID');
		} elseif (isset($this->urlParams['ID']) && is_numeric($this->urlParams['ID'])) {
			return $this->urlParams['ID'];
		} elseif(Session::get("{$this->class}.currentPage")) {
			return Session::get("{$this->class}.currentPage");
		} else {
			return 0;
		}
	}

	/**
	 * Set up the controller
	 */
	public function init() {
		parent::init();

		Versioned::set_stage(Versioned::DRAFT);

		Requirements::javascript(CMS_DIR . "/client/dist/js/AssetAdmin.js");
		Requirements::add_i18n_javascript(CMS_DIR . '/client/lang', false, true);
		Requirements::css(CMS_DIR . '/client/dist/styles/bundle.css');
		CMSBatchActionHandler::register('delete', 'SilverStripe\\CMS\\Controllers\\AssetAdmin_DeleteBatchAction', 'Folder');
	}

	/**
	 * Returns the files and subfolders contained in the currently selected folder,
	 * defaulting to the root node. Doubles as search results, if any search parameters
	 * are set through {@link SearchForm()}.
	 *
	 * @return SS_List
	 */
	public function getList() {
		$folder = $this->currentPage();
		$context = $this->getSearchContext();
		// Overwrite name filter to search both Name and Title attributes
		$context->removeFilterByName('Name');
		$params = $this->getRequest()->requestVar('q');
		/** @var DataList $list */
		$list = $context->getResults($params);

		// Don't filter list when a detail view is requested,
		// to avoid edge cases where the filtered list wouldn't contain the requested
		// record due to faulty session state (current folder not always encoded in URL, see #7408).
		if(!$folder->ID
			&& $this->getRequest()->requestVar('ID') === null
			&& ($this->getRequest()->param('ID') == 'field')
		) {
			return $list;
		}

		// Re-add previously removed "Name" filter as combined filter
		// TODO Replace with composite SearchFilter once that API exists
		if(!empty($params['Name'])) {
			$list = $list->filterAny(array(
				'Name:PartialMatch' => $params['Name'],
				'Title:PartialMatch' => $params['Name']
			));
		}

		// Always show folders at the top
		$list = $list->sort('(CASE WHEN "File"."ClassName" = \'Folder\' THEN 0 ELSE 1 END), "Name"');

		// If a search is conducted, check for the "current folder" limitation.
		// Otherwise limit by the current folder as denoted by the URL.
		if(empty($params) || !empty($params['CurrentFolderOnly'])) {
			$list = $list->filter('ParentID', $folder->ID);
		}

		// Category filter
		if(!empty($params['AppCategory'])
			&& !empty(File::config()->app_categories[$params['AppCategory']])
		) {
			$exts = File::config()->app_categories[$params['AppCategory']];
			$list = $list->filter('Name:PartialMatch', $exts);
		}

		// Date filter
		if(!empty($params['CreatedFrom'])) {
			$fromDate = new DateField(null, null, $params['CreatedFrom']);
			$list = $list->filter("Created:GreaterThanOrEqual", $fromDate->dataValue().' 00:00:00');
		}
		if(!empty($params['CreatedTo'])) {
			$toDate = new DateField(null, null, $params['CreatedTo']);
			$list = $list->filter("Created:LessThanOrEqual", $toDate->dataValue().' 23:59:59');
		}

		return $list;
	}

	public function getEditForm($id = null, $fields = null) {
		Requirements::javascript(FRAMEWORK_DIR . '/client/dist/js/AssetUploadField.js');
		Requirements::css(FRAMEWORK_DIR . '/client/dist/styles/AssetUploadField.css');

		$form = parent::getEditForm($id, $fields);
		$folder = ($id && is_numeric($id)) ? DataObject::get_by_id('Folder', $id, false) : $this->currentPage();
		$fields = $form->Fields();
		$title = ($folder && $folder->isInDB()) ? $folder->Title : _t('AssetAdmin.FILES', 'Files');
		$fields->push(new HiddenField('ID', false, $folder ? $folder->ID : null));

		// Remove legacy previewable behaviour.
		$form->removeExtraClass('cms-previewable');
		/** @skipUpgrade */
		$form->Fields()->removeByName('SilverStripeNavigator');

		// File listing
		$gridFieldConfig = GridFieldConfig::create()->addComponents(
			new GridFieldToolbarHeader(),
			new GridFieldSortableHeader(),
			new GridFieldFilterHeader(),
			new GridFieldDataColumns(),
			new GridFieldPaginator(self::config()->page_length),
			new GridFieldEditButton(),
			new GridFieldDeleteAction(),
			new GridFieldDetailForm(),
			GridFieldLevelup::create($folder->ID)->setLinkSpec($this->Link('show') . '/%d')
		);

		$gridField = GridField::create('File', $title, $this->getList(), $gridFieldConfig);
		/** @var GridFieldDataColumns $columns */
		$columns = $gridField->getConfig()->getComponentByType('GridFieldDataColumns');
		$columns->setDisplayFields(array(
			'StripThumbnail' => '',
			'Title' => _t('File.Title', 'Title'),
			'Created' => _t('AssetAdmin.CREATED', 'Date'),
			'Size' => _t('AssetAdmin.SIZE', 'Size'),
		));
		$columns->setFieldCasting(array(
			'Created' => 'DBDatetime->Nice'
		));
		$gridField->setAttribute(
			'data-url-folder-template',
			Controller::join_links($this->Link('show'), '%s')
		);

		if(!$folder->hasMethod('canAddChildren') || ($folder->hasMethod('canAddChildren') && $folder->canAddChildren())) {
			// TODO Will most likely be replaced by GridField logic
			$addFolderBtn = new LiteralField(
				'AddFolderButton',
				sprintf(
					'<a class="ss-ui-button font-icon-folder-add no-text cms-add-folder-link" title="%s" data-icon="add" data-url="%s" href="%s"></a>',
					_t('Folder.AddFolderButton', 'Add folder'),
					Controller::join_links($this->Link('AddForm'), '?' . http_build_query(array(
						'action_doAdd' => 1,
						'ParentID' => $folder->ID,
						'SecurityID' => $form->getSecurityToken()->getValue()
					))),
					Controller::join_links($this->Link('addfolder'), '?ParentID=' . $folder->ID)
				)
			);
		} else {
			$addFolderBtn = '';
		}

		// Move existing fields to a "details" tab, unless they've already been tabbed out through extensions.
		// Required to keep Folder->getCMSFields() simple and reuseable,
		// without any dependencies into AssetAdmin (e.g. useful for "add folder" views).
		if(!$fields->hasTabSet()) {
			$tabs = new TabSet('Root',
				$tabList = new Tab('ListView', _t('AssetAdmin.ListView', 'List View')),
				$tabTree = new Tab('TreeView', _t('AssetAdmin.TreeView', 'Tree View'))
			);
			$tabList->addExtraClass("content-listview cms-tabset-icon list");
			$tabTree->addExtraClass("content-treeview cms-tabset-icon tree");
			if($fields->count() && $folder && $folder->isInDB()) {
				$tabs->push($tabDetails = new Tab('DetailsView', _t('AssetAdmin.DetailsView', 'Details')));
				$tabDetails->addExtraClass("content-galleryview cms-tabset-icon edit");
				foreach($fields as $field) {
					$fields->removeByName($field->getName());
					$tabDetails->push($field);
				}
			}
			$fields->push($tabs);
		}

		// we only add buttons if they're available. User might not have permission and therefore
		// the button shouldn't be available. Adding empty values into a ComposteField breaks template rendering.
		$actionButtonsComposite = CompositeField::create()->addExtraClass('cms-actions-row');
		if($addFolderBtn) $actionButtonsComposite->push($addFolderBtn);

		// Add the upload field for new media
		if($currentPageID = $this->currentPageID()){
			Session::set("{$this->class}.currentPage", $currentPageID);
		}

		$folder = $this->currentPage();

		$uploadField = UploadField::create('AssetUploadField', '');
		$uploadField->setConfig('previewMaxWidth', 40);
		$uploadField->setConfig('previewMaxHeight', 30);
		$uploadField->setConfig('changeDetection', false);
		$uploadField->addExtraClass('ss-assetuploadfield');
		$uploadField->removeExtraClass('ss-uploadfield');
		$uploadField->setTemplate('AssetUploadField');

		if($folder->exists()) {
			$path = $folder->getFilename();
			$uploadField->setFolderName($path);
		} else {
			$uploadField->setFolderName('/'); // root of the assets
		}

		$exts = $uploadField->getValidator()->getAllowedExtensions();
		asort($exts);
		$uploadField->Extensions = implode(', ', $exts);

		// List view
		$fields->addFieldsToTab('Root.ListView', array(
			$actionsComposite = CompositeField::create(
				$actionButtonsComposite
			)->addExtraClass('cms-content-toolbar field'),
			$uploadField,
			new HiddenField('ID'),
			$gridField
		));

		// Tree view
		$fields->addFieldsToTab('Root.TreeView', array(
			clone $actionsComposite,
			// TODO Replace with lazy loading on client to avoid performance hit of rendering potentially unused views
			new LiteralField(
				'Tree',
				FormField::create_tag(
					'div',
					array(
						'class' => 'cms-tree',
						'data-url-tree' => $this->Link('getsubtree'),
						'data-url-savetreenode' => $this->Link('savetreenode')
					),
					$this->SiteTreeAsUL()
				)
			)
		));

		// Move actions to "details" tab (they don't make sense on list/tree view)
		$actions = $form->Actions();
		$saveBtn = $actions->fieldByName('action_save');
		$deleteBtn = $actions->fieldByName('action_delete');
		$actions->removeByName('action_save');
		$actions->removeByName('action_delete');
		if(($saveBtn || $deleteBtn) && $fields->fieldByName('Root.DetailsView')) {
			$fields->addFieldToTab(
				'Root.DetailsView',
				CompositeField::create($saveBtn,$deleteBtn)->addExtraClass('Actions')
			);
		}


		$fields->setForm($form);
		$form->setTemplate($this->getTemplatesWithSuffix('_EditForm'));
		// TODO Can't merge $FormAttributes in template at the moment
		$form->addExtraClass('cms-edit-form ' . $this->BaseCSSClasses());
		$form->setAttribute('data-pjax-fragment', 'CurrentForm');
		$form->Fields()->findOrMakeTab('Root')->setTemplate('CMSTabSet');

		// Optionally handle form submissions with 'X-Formschema-Request'
		// which rely on having validation errors returned as structured data
		$form->setValidationResponseCallback(function() use ($form) {
			$request = $this->getRequest();
			if($request->getHeader('X-Formschema-Request')) {
				$data = $this->getSchemaForForm($form);
				$response = new SS_HTTPResponse(Convert::raw2json($data));
				$response->addHeader('Content-Type', 'application/json');
				return $response;

			}
		});


		$this->extend('updateEditForm', $form);

		return $form;
	}

	/**
	 * @param SS_HTTPRequest $request
	 * @return DBHTMLText
	 */
	public function addfolder($request) {
		$obj = $this->customise(array(
			'EditForm' => $this->AddForm()
		));

		if($request->isAjax()) {
			// Rendering is handled by template, which will call EditForm() eventually
			$content = $obj->renderWith($this->getTemplatesWithSuffix('_Content'));
		} else {
			$content = $obj->renderWith($this->getViewer('show'));
		}

		return $content;
	}

	public function delete($data, $form) {
		$className = $this->stat('tree_class');

		$record = DataObject::get_by_id($className, $data['ID']);
		if($record && !$record->canDelete()) {
			return Security::permissionFailure();
		}
		if(!$record || !$record->ID) {
			throw new SS_HTTPResponse_Exception("Bad record ID #" . (int)$data['ID'], 404);
		}
		$parentID = $record->ParentID;
		$record->delete();
		$this->setCurrentPageID(null);

		$this->getResponse()->addHeader('X-Status', rawurlencode(_t('LeftAndMain.DELETED', 'Deleted.')));
		$this->getResponse()->addHeader('X-Pjax', 'Content');
		return $this->redirect(Controller::join_links($this->Link('show'), $parentID ? $parentID : 0));
	}

	/**
	 * Get the search context
	 *
	 * @return SearchContext
	 */
	public function getSearchContext() {
		$context = File::singleton()->getDefaultSearchContext();

		// Namespace fields, for easier detection if a search is present
		/** @var FormField $field */
		foreach($context->getFields() as $field) {
			$field->setName(sprintf('q[%s]', $field->getName()));
		}
		/** @var SearchFilter $filter */
		foreach($context->getFilters() as $filter) {
			$filter->setFullName(sprintf('q[%s]', $filter->getFullName()));
		}

		// Customize fields
		$dateHeader = HeaderField::create('q[Date]', _t('CMSSearch.FILTERDATEHEADING', 'Date'), 4);
		$dateFrom = DateField::create('q[CreatedFrom]', _t('CMSSearch.FILTERDATEFROM', 'From'))
		->setConfig('showcalendar', true);
		$dateTo = DateField::create('q[CreatedTo]',_t('CMSSearch.FILTERDATETO', 'To'))
		->setConfig('showcalendar', true);
		$dateGroup = FieldGroup::create(
			$dateHeader,
			$dateFrom,
			$dateTo
		);
		$context->addField($dateGroup);
		$appCategories = array(
			'archive' => _t('AssetAdmin.AppCategoryArchive', 'Archive', 'A collection of files'),
			'audio' => _t('AssetAdmin.AppCategoryAudio', 'Audio'),
			'document' => _t('AssetAdmin.AppCategoryDocument', 'Document'),
			'flash' => _t('AssetAdmin.AppCategoryFlash', 'Flash', 'The fileformat'),
			'image' => _t('AssetAdmin.AppCategoryImage', 'Image'),
			'video' => _t('AssetAdmin.AppCategoryVideo', 'Video'),
		);
		$context->addField(
			$typeDropdown = new DropdownField(
				'q[AppCategory]',
				_t('AssetAdmin.Filetype', 'File type'),
				$appCategories
			)
		);

		$typeDropdown->setEmptyString(' ');

		$context->addField(
			new CheckboxField('q[CurrentFolderOnly]', _t('AssetAdmin.CurrentFolderOnly', 'Limit to current folder?'))
		);
		$context->getFields()->removeByName('q[Title]');

		return $context;
	}

	/**
	 * Returns a form for filtering of files and assets gridfield.
	 * Result filtering takes place in {@link getList()}.
	 *
	 * @return Form
	 * @see AssetAdmin.js
	 */
	public function SearchForm() {
		$folder = $this->currentPage();
		$context = $this->getSearchContext();

		$fields = $context->getSearchFields();
		$actions = new FieldList(
			FormAction::create('doSearch',  _t('CMSMain_left_ss.APPLY_FILTER', 'Apply Filter'))
				->addExtraClass('ss-ui-action-constructive'),
			Object::create('ResetFormAction', 'clear', _t('CMSMain_left_ss.RESET', 'Reset'))
		);

		$form = new Form($this, 'filter', $fields, $actions);
		$form->setFormMethod('GET');
		$form->setFormAction(Controller::join_links($this->Link('show'), $folder->ID));
		$form->addExtraClass('cms-search-form');
		$form->loadDataFrom($this->getRequest()->getVars());
		$form->disableSecurityToken();
		// This have to match data-name attribute on the gridfield so that the javascript selectors work
		$form->setAttribute('data-gridfield', 'File');
		return $form;
	}

	public function AddForm() {
		$negotiator = $this->getResponseNegotiator();
		$form = Form::create(
			$this,
			'AddForm',
			new FieldList(
				new TextField("Name", _t('File.Name')),
				new HiddenField('ParentID', false, $this->getRequest()->getVar('ParentID'))
			),
			new FieldList(
				FormAction::create('doAdd', _t('AssetAdmin_left_ss.GO','Go'))
					->addExtraClass('ss-ui-action-constructive')->setAttribute('data-icon', 'accept')
					->setTitle(_t('AssetAdmin.ActionAdd', 'Add folder'))
			)
		)->setHTMLID('Form_AddForm');
		$form->setValidationResponseCallback(function() use ($negotiator, $form) {
			$request = $this->getRequest();
			if($request->isAjax() && $negotiator) {
				$form->setupFormErrors();
				$result = $form->forTemplate();

				return $negotiator->respond($request, array(
					'CurrentForm' => function() use($result) {
						return $result;
					}
				));
			}
		});
		$form->setTemplate($this->getTemplatesWithSuffix('_EditForm'));
		// TODO Can't merge $FormAttributes in template at the moment
		$form->addExtraClass('add-form cms-add-form cms-edit-form cms-panel-padded center ' . $this->BaseCSSClasses());

		return $form;
	}

	/**
	 * Add a new group and return its details suitable for ajax.
	 *
	 * @todo Move logic into Folder class, and use LeftAndMain->doAdd() default implementation.
	 *
	 * @param array $data
	 * @param Form $form
	 * @return SS_HTTPResponse|string
	 */
	public function doAdd($data, $form) {
		$class = $this->stat('tree_class');

		// check create permissions
		if(!singleton($class)->canCreate()) {
			return Security::permissionFailure($this);
		}

		// check addchildren permissions
		/** @var File $parentRecord */
		if(
			singleton($class)->hasExtension('SilverStripe\ORM\Hierarchy\Hierarchy')
			&& isset($data['ParentID'])
			&& is_numeric($data['ParentID'])
			&& $data['ParentID']
		) {
			$parentRecord = DataObject::get_by_id($class, $data['ParentID']);
			if($parentRecord->hasMethod('canAddChildren') && !$parentRecord->canAddChildren()) {
				return Security::permissionFailure($this);
			}
		} else {
			$parentRecord = null;
		}

		// Check parent
		$parentID = $parentRecord && $parentRecord->ID
			? (int)$parentRecord->ID
			: 0;
		// Build filename
		$filename = isset($data['Name'])
			? basename($data['Name'])
			: _t('AssetAdmin.NEWFOLDER',"NewFolder");
		if($parentRecord && $parentRecord->ID) {
			$filename = $parentRecord->getFilename() . '/' . $filename;
		}

		// Get the folder to be created

		// Ensure name is unique
		foreach($this->getNameGenerator($filename) as $filename) {
			if(! File::find($filename) ) {
				break;
			}
		}

		// Create record
		$record = Folder::create();
		$record->ParentID = $parentID;
		$record->Name = $record->Title = basename($filename);
		$record->write();


		if($parentRecord) {
			return $this->redirect(Controller::join_links($this->Link('show'), $parentRecord->ID));
		} else {
			return $this->redirect($this->Link());
		}
	}

	/**
	 * Get an asset renamer for the given filename.
	 *
	 * @param string $filename Path name
	 * @return AssetNameGenerator
	 */
	protected function getNameGenerator($filename){
		return Injector::inst()
			->createWithArgs('AssetNameGenerator', array($filename));
	}

	/**
	 * Custom currentPage() method to handle opening the 'root' folder
	 */
	public function currentPage() {
		$id = $this->currentPageID();
		if($id && is_numeric($id) && $id > 0) {
			$folder = DataObject::get_by_id('Folder', $id);
			if($folder && $folder->isInDB()) {
				return $folder;
			}
		}
		$this->setCurrentPageID(null);
		return new Folder();
	}

	public function getSiteTreeFor($className, $rootID = null, $childrenMethod = null, $numChildrenMethod = null, $filterFunction = null, $minNodeCount = 30) {
		if (!$childrenMethod) $childrenMethod = 'ChildFolders';
		if (!$numChildrenMethod) $numChildrenMethod = 'numChildFolders';
		return parent::getSiteTreeFor($className, $rootID, $childrenMethod, $numChildrenMethod, $filterFunction, $minNodeCount);
	}

	public function getCMSTreeTitle() {
		return Director::absoluteBaseURL() . "assets";
	}

	public function SiteTreeAsUL() {
		return $this->getSiteTreeFor($this->stat('tree_class'), null, 'ChildFolders', 'numChildFolders');
	}

	/**
	 * @param bool $unlinked
	 * @return ArrayList
	 */
	public function Breadcrumbs($unlinked = false) {
		$items = parent::Breadcrumbs($unlinked);

		// The root element should explicitly point to the root node.
		// Uses session state for current record otherwise.
		$items[0]->Link = Controller::join_links($this->Link('show'), 0);

		// If a search is in progress, don't show the path
		if($this->getRequest()->requestVar('q')) {
			$items = $items->limit(1);
			$items->push(new ArrayData(array(
				'Title' => _t('LeftAndMain.SearchResults', 'Search Results'),
				'Link' => Controller::join_links($this->Link(), '?' . http_build_query(array('q' => $this->getRequest()->requestVar('q'))))
			)));
		}

		// If we're adding a folder, note that in breadcrumbs as well
		if($this->getRequest()->param('Action') == 'addfolder') {
			$items->push(new ArrayData(array(
				'Title' => _t('Folder.AddFolderButton', 'Add folder'),
				'Link' => false
			)));
		}

		return $items;
	}

	public static function menu_title($class = null, $localised = true) {
		// Deprecate this menu title if installed alongside new asset admin
		if($localised && class_exists('SilverStripe\AssetAdmin\Controller\AssetAdmin')) {
			// Don't conflict with legacy translations
			return _t('AssetAdmin.CMSMENU_OLD', 'Files (old)');
		}
		return parent::menu_title(null, $localised);
	}

	public function providePermissions() {
		$title = static::menu_title();
		return array(
			"CMS_ACCESS_AssetAdmin" => array(
				'name' => _t('CMSMain.ACCESS', "Access to '{title}' section", array('title' => $title)),
				'category' => _t('Permission.CMS_ACCESS_CATEGORY', 'CMS Access')
			)
		);
	}

}