<?php
/**
 * TThemeManager class
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2014 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @package Prado\Web\UI
 */

namespace Prado\Web\UI;
use Prado\Exceptions\TIOException;
use Prado\Exceptions\TConfigurationException;
use Prado\Prado;
use Prado\TApplicationMode;

/**
 * TTheme class
 *
 * TTheme represents a particular theme. It is merely a collection of skins
 * that are applicable to the corresponding controls.
 *
 * Each theme is stored as a directory and files under that directory.
 * The theme name is the directory name. When TTheme is created, the files
 * whose name has the extension ".skin" are parsed and saved as controls skins.
 *
 * A skin is essentially a list of initial property values that are to be applied
 * to a control when the skin is applied.
 * Each type of control can have multiple skins identified by the SkinID.
 * If a skin does not have SkinID, it is the default skin that will be applied
 * to controls that do not specify particular SkinID.
 *
 * Whenever possible, TTheme will try to make use of available cache to save
 * the parsing time.
 *
 * To apply a theme to a particular control, call {@link applySkin}.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package Prado\Web\UI
 * @since 3.0
 */
class TTheme extends \Prado\TApplicationComponent implements ITheme
{
	/**
	 * prefix for cache variable name used to store parsed themes
	 */
	const THEME_CACHE_PREFIX='prado:theme:';
	/**
	 * Extension name of skin files
	 */
	const SKIN_FILE_EXT='.skin';
	/**
	 * @var string theme path
	 */
	private $_themePath;
	/**
	 * @var string theme url
	 */
	private $_themeUrl;
	/**
	 * @var array list of skins for the theme
	 */
	private $_skins=null;
	/**
	 * @var string theme name
	 */
	private $_name='';
	/**
	 * @var array list of css files
	 */
	private $_cssFiles=array();
	/**
	 * @var array list of js files
	 */
	private $_jsFiles=array();

	/**
	 * Constructor.
	 * @param string theme path
	 * @param string theme URL
	 * @throws TConfigurationException if theme path does not exist or any parsing error of the skin files
	 */
	public function __construct($themePath,$themeUrl)
	{
		$this->_themeUrl=$themeUrl;
		$this->_themePath=realpath($themePath);
		$this->_name=basename($themePath);
		$cacheValid=false;
		// TODO: the following needs to be cleaned up (Qiang)
		if(($cache=$this->getApplication()->getCache())!==null)
		{
			$array=$cache->get(self::THEME_CACHE_PREFIX.$themePath);
			if(is_array($array))
			{
				list($skins,$cssFiles,$jsFiles,$timestamp)=$array;
				if($this->getApplication()->getMode()!==TApplicationMode::Performance)
				{
					if(($dir=opendir($themePath))===false)
						throw new TIOException('theme_path_inexistent',$themePath);
					$cacheValid=true;
					while(($file=readdir($dir))!==false)
					{
						if($file==='.' || $file==='..')
							continue;
						else if(basename($file,'.css')!==$file)
							$this->_cssFiles[]=$themeUrl.'/'.$file;
						else if(basename($file,'.js')!==$file)
							$this->_jsFiles[]=$themeUrl.'/'.$file;
						else if(basename($file,self::SKIN_FILE_EXT)!==$file && filemtime($themePath.DIRECTORY_SEPARATOR.$file)>$timestamp)
						{
							$cacheValid=false;
							break;
						}
					}
					closedir($dir);
					if($cacheValid)
						$this->_skins=$skins;
				}
				else
				{
					$cacheValid=true;
					$this->_cssFiles=$cssFiles;
					$this->_jsFiles=$jsFiles;
					$this->_skins=$skins;
				}
			}
		}
		if(!$cacheValid)
		{
			$this->_cssFiles=array();
			$this->_jsFiles=array();
			$this->_skins=array();
			if(($dir=opendir($themePath))===false)
				throw new TIOException('theme_path_inexistent',$themePath);
			while(($file=readdir($dir))!==false)
			{
				if($file==='.' || $file==='..')
					continue;
				else if(basename($file,'.css')!==$file)
					$this->_cssFiles[]=$themeUrl.'/'.$file;
				else if(basename($file,'.js')!==$file)
					$this->_jsFiles[]=$themeUrl.'/'.$file;
				else if(basename($file,self::SKIN_FILE_EXT)!==$file)
				{
					$template=new TTemplate(file_get_contents($themePath.'/'.$file),$themePath,$themePath.'/'.$file);
					foreach($template->getItems() as $skin)
					{
						if(!isset($skin[2]))  // a text string, ignored
							continue;
						else if($skin[0]!==-1)
							throw new TConfigurationException('theme_control_nested',$skin[1],dirname($themePath));
						$type=$skin[1];
						$id=isset($skin[2]['skinid'])?$skin[2]['skinid']:0;
						unset($skin[2]['skinid']);
						if(isset($this->_skins[$type][$id]))
							throw new TConfigurationException('theme_skinid_duplicated',$type,$id,dirname($themePath));
						/*
						foreach($skin[2] as $name=>$value)
						{
							if(is_array($value) && ($value[0]===TTemplate::CONFIG_DATABIND || $value[0]===TTemplate::CONFIG_PARAMETER))
								throw new TConfigurationException('theme_databind_forbidden',dirname($themePath),$type,$id);
						}
						*/
						$this->_skins[$type][$id]=$skin[2];
					}
				}
			}
			closedir($dir);
			sort($this->_cssFiles);
			sort($this->_jsFiles);
			if($cache!==null)
				$cache->set(self::THEME_CACHE_PREFIX.$themePath,array($this->_skins,$this->_cssFiles,$this->_jsFiles,time()));
		}
	}

	/**
	 * @return string theme name
	 */
	public function getName()
	{
		return $this->_name;
	}

	/**
	 * @param string theme name
	 */
	protected function setName($value)
	{
		$this->_name = $value;
	}

	/**
	 * @return string the URL to the theme folder (without ending slash)
	 */
	public function getBaseUrl()
	{
		return $this->_themeUrl;
	}

	/**
	 * @param string the URL to the theme folder
	 */
	protected function setBaseUrl($value)
	{
		$this->_themeUrl=rtrim($value,'/');
	}

	/**
	 * @return string the file path to the theme folder
	 */
	public function getBasePath()
	{
		return $this->_themePath;
	}

	/**
	 * @param string tthe file path to the theme folder
	 */
	protected function setBasePath($value)
	{
		$this->_themePath=$value;
	}

	/**
	 * @return array list of skins for the theme
	 */
	public function getSkins()
	{
		return $this->_skins;
	}

	/**
	 * @param array list of skins for the theme
	 */
	protected function setSkins($value)
	{
		$this->_skins = $value;
	}

	/**
	 * Applies the theme to a particular control.
	 * The control's class name and SkinID value will be used to
	 * identify which skin to be applied. If the control's SkinID is empty,
	 * the default skin will be applied.
	 * @param TControl the control to be applied with a skin
	 * @return boolean if a skin is successfully applied
	 * @throws TConfigurationException if any error happened during the skin application
	 */
	public function applySkin($control)
	{
		$type=get_class($control);
		if(($id=$control->getSkinID())==='')
			$id=0;
		if(isset($this->_skins[$type][$id]))
		{
			foreach($this->_skins[$type][$id] as $name=>$value)
			{
				Prado::trace("Applying skin $name to $type",'Prado\Web\UI\TThemeManager');
				if(is_array($value))
				{
					switch($value[0])
					{
						case TTemplate::CONFIG_EXPRESSION:
							$value=$this->evaluateExpression($value[1]);
							break;
						case TTemplate::CONFIG_ASSET:
							$value=$this->_themeUrl.'/'.ltrim($value[1],'/');
							break;
						case TTemplate::CONFIG_DATABIND:
							$control->bindProperty($name,$value[1]);
							break;
						case TTemplate::CONFIG_PARAMETER:
							$control->setSubProperty($name,$this->getApplication()->getParameters()->itemAt($value[1]));
							break;
						case TTemplate::CONFIG_TEMPLATE:
							$control->setSubProperty($name,$value[1]);
							break;
						case TTemplate::CONFIG_LOCALIZATION:
							$control->setSubProperty($name,Prado::localize($value[1]));
							break;
						default:
							throw new TConfigurationException('theme_tag_unexpected',$name,$value[0]);
							break;
					}
				}
				if(!is_array($value))
				{
					if(strpos($name,'.')===false)	// is simple property or custom attribute
					{
						if($control->hasProperty($name))
						{
							if($control->canSetProperty($name))
							{
								$setter='set'.$name;
								$control->$setter($value);
							}
							else
								throw new TConfigurationException('theme_property_readonly',$type,$name);
						}
						else
							throw new TConfigurationException('theme_property_undefined',$type,$name);
					}
					else	// complex property
						$control->setSubProperty($name,$value);
				}
			}
			return true;
		}
		else
			return false;
	}

	/**
	 * @return array list of CSS files (URL) in the theme
	 */
	public function getStyleSheetFiles()
	{
		return $this->_cssFiles;
	}

	/**
	 * @param array list of CSS files (URL) in the theme
	 */
	protected function setStyleSheetFiles($value)
	{
		$this->_cssFiles=$value;
	}

	/**
	 * @return array list of Javascript files (URL) in the theme
	 */
	public function getJavaScriptFiles()
	{
		return $this->_jsFiles;
	}

	/**
	 * @param array list of Javascript files (URL) in the theme
	 */
	protected function setJavaScriptFiles($value)
	{
		$this->_jsFiles=$value;
	}
}