savant2.php

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		// find the template source.
		$file = $this->findFile('template', $tpl);
		if (! $file) {
			return $this->error(
				SAVANT2_ERROR_NOTEMPLATE,
				array('template' => $tpl)
			);
		}
		
		// are we compiling source into a script?
		if (is_object($this->_compiler)) {
			// compile the template source and get the path to the
			// compiled script (will be returned instead of the
			// source path)
			$result = $this->_compiler->compile($file);
		} else {
			// no compiling requested, return the source path
			$result = $file;
		}
		
		// is there a script from the compiler?
		if (! $result || $this->isError($result)) {
		
			if ($setScript) {
				$this->_script = null;
			}
			
			// return an error, along with any error info
			// generated by the compiler.
			return $this->error(
				SAVANT2_ERROR_NOSCRIPT,
				array(
					'template' => $tpl,
					'compiler' => $result
				)
			);
			
		} else {
		
			if ($setScript) {
				$this->_script = $result;
			}
			
			return $result;
			
		}
	}
	
	
	/**
	* 
	* This is a an alias to loadTemplate() that cannot set the script.
	* 
	* @access public
	*
	* @param string $tpl The template source name to look for.
	* 
	* @return string The full path to the compiled template script.
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOTEMPLATE code.
	* 
	*/
	
	function findTemplate($tpl = null)
	{
		return $this->loadTemplate($tpl, false);
	}
	
	
	/**
	* 
	* Executes a template script and returns the results as a string.
	* 
	* @param string $_tpl The name of the template source file ...
	* automatically searches the template paths and compiles as needed.
	* 
	* @return string The output of the the template script.
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOSCRIPT code.
	* 
	*/
	
	function fetch($_tpl = null)
	{
		// clear prior output
		$this->_output = null;
		
		// load the template script
		$_result = $this->loadTemplate($_tpl, true);
		
		// is there a template script to be processed?
		if ($this->isError($_result)) {
			return $_result;
		}
		
		// unset so as not to introduce into template scope
		unset($_tpl);
		unset($_result);
		
		// never allow a 'this' property
		if (isset($this->this)) {
			unset($this->this);
		}
		
		// are we extracting variables into local scope?
		if ($this->_extract) {
			// extract references to this object's public properties.
			// this allows variables assigned by-reference to refer all
			// the way back to the model logic.  variables assigned
			// by-copy only refer back to the property.
			foreach (array_keys(get_object_vars($this)) as $_prop) {
				if (substr($_prop, 0, 1) != '_') {
					// set a variable-variable to an object property
					// reference
					$$_prop =& $this->$_prop;
				}
			}
			
			// unset private loop vars
			unset($_prop);
		}
		
		// start capturing output into a buffer
		ob_start();
		
		// include the requested template filename in the local scope
		// (this will execute the view logic).
		include $this->_script;
		
		// done with the requested template; get the buffer and 
		// clear it.
		$this->_output = ob_get_contents();
		ob_end_clean();
		
		// done!
		return $this->applyFilters();
	}
	
	
	/**
	* 
	* Execute and display a template script.
	* 
	* @param string $tpl The name of the template file to parse;
	* automatically searches through the template paths.
	* 
	* @return void
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOSCRIPT code.
	* 
	* @see fetch()
	* 
	*/
	
	function display($tpl = null)
	{
		$result = $this->fetch($tpl);
		if ($this->isError($result)) {
			return $result;
		} else {
			echo $result;
		}
	}
	
	
	// -----------------------------------------------------------------
	//
	// Plugins
	//
	// -----------------------------------------------------------------
	
	
	/**
	*
	* Loads a plugin class and instantiates it within Savant2.
	*
	* @access public
	*
	* @param string $name The plugin name (not including Savant2_Plugin_
	* prefix).
	*
	* @param array $conf An associative array of plugin configuration
	* options.
	*
	* @param bool $savantRef Default false.  When true, sets the $Savant
	* property of the filter to a reference to this Savant object.
	*
	* @return void
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOPLUGIN code.
	* 
	*/
	
	function loadPlugin($name, $conf = array(), $savantRef = null)
	{
		// if no $savantRef is provided, use the default.
		if (is_null($savantRef)) {
			$savantRef = $this->_reference;
		}
		
		// some basic information
		$class = "Savant2_Plugin_$name";
		$file = "$class.php";
		
		// is it loaded?
		if (! $this->_classExists($class)) {
			
			$result = $this->findFile('resource', $file);
			if (! $result) {
				return $this->error(
					SAVANT2_ERROR_NOPLUGIN,
					array('plugin' => $name)
				);
			} else {
				include_once $result;
			}
		}
		
		// is it instantiated?
		if (! isset($this->_resource['plugin'][$name]) ||
			! is_object($this->_resource['plugin'][$name]) ||
			! is_a($this->_resource['plugin'][$name], $class)) {
			
			// instantiate it
			$this->_resource['plugin'][$name] =& new $class($conf);
			
			// add a Savant reference if requested
			if ($savantRef) {
				$this->_resource['plugin'][$name]->Savant =& $this;
			}
			
		}
	}
	
	
	/**
	*
	* Unloads one or more plugins from Savant2.
	*
	* @access public
	*
	* @param string|array $name The plugin name (not including Savant2_Plugin_
	* prefix).  If null, unloads all plugins; if a string, unloads that one
	* plugin; if an array, unloads all plugins named as values in the array.
	*
	* @return void
	* 
	*/
	
	function unloadPlugin($name = null)
	{
		if (is_null($name)) {
			$this->_resource['plugin'] = array();
		} else {
			settype($name, 'array');
			foreach ($name as $key) {
				if (isset($this->_resource['plugin'][$key])) {
					unset($this->_resource['plugin'][$key]);
				}
			}
		}
	}
	
	
	/**
	*
	* Executes a plugin with arbitrary parameters and returns the
	* result.
	* 
	* @access public
	* 
	* @param string $name The plugin name (not including Savant2_Plugin_
	* prefix).
	*
	* @return mixed The plugin results.
	*
	* @throws object An error object with a SAVANT2_ERROR_NOPLUGIN code.
	* 
	* @see loadPlugin()
	* 
	*/
	
	function splugin($name)
	{
		// attempt to load the plugin
		$result = $this->loadPlugin($name);
		if ($this->isError($result)) {
			return $result;
		}
		
		// call the plugin's "plugin()" method with arguments,
		// dropping the first argument (the plugin name)
		$args = func_get_args();
		array_shift($args);
		return call_user_func_array(
			array(&$this->_resource['plugin'][$name], 'plugin'), $args
		);
	}
	
	
	/**
	*
	* Executes a plugin with arbitrary parameters and displays the
	* result.
	* 
	* @access public
	* 
	* @param string $name The plugin name (not including Savant2_Plugin_
	* prefix).
	*
	* @return void
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOPLUGIN code.
	* 
	*/
	
	function plugin($name)
	{
		$args = func_get_args();
		
		$result = call_user_func_array(
			array(&$this, 'splugin'),
			$args
		);
		
		if ($this->isError($result)) {
			return $result;
		} else {
			echo $result;
		}
	}
	
	
	/**
	*
	* PHP5 ONLY: Magic method alias to plugin().
	* 
	* E.g., instead of $this->plugin('form', ...) you would use
	* $this->form(...).  You can set this to use any other Savant2 method
	* by issuing, for example, setCall('splugin') to use splugin() ... which 
	* is really the only other sensible choice.
	* 
	* @access public
	* 
	* @param string $func The plugin name.
	*
	* @param array $args Arguments passed to the plugin.
	*
	* @return void
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOPLUGIN code.
	* 
	*/
	
	function __call($func, $args)
	{
		// add the plugin name to the args
		array_unshift($args, $func);
		
		// call the plugin() method
		return call_user_func_array(
			array(&$this, $this->_call),
			$args
		);
	}
	
	
	// -----------------------------------------------------------------
	//
	// Filters
	//
	// -----------------------------------------------------------------
	
	
	/**
	*
	* Loads a filter class and instantiates it within Savant2.
	*
	* @access public
	*
	* @param string $name The filter name (not including Savant2_Filter_
	* prefix).
	*
	* @param array $conf An associative array of filter configuration
	* options.
	* 
	* @param bool $savantRef Default false.  When true, sets the $Savant
	* property of the filter to a reference to this Savant object.
	*
	* @return void
	* 
	* @throws object An error object with a SAVANT2_ERROR_NOFILTER code.
	* 
	*/
	
	function loadFilter($name, $conf = array(), $savantRef = null)
	{
		// if no $savantRef is provided, use the default.
		if (is_null($savantRef)) {
			$savantRef = $this->_reference;
		}
		
		// some basic information
		$class = "Savant2_Filter_$name";
		$file = "$class.php";
		
		// is it loaded?
		if (! $this->_classExists($class)) {
			
			$result = $this->findFile('resource', $file);
			if (! $result) {
				return $this->error(
					SAVANT2_ERROR_NOFILTER,
					array('filter' => $name)
				);
			} else {
				include_once $result;
			}
		}
		
		// is it instantiated?
		if (! isset($this->_resource['filter'][$name]) ||
			! is_object($this->_resource['filter'][$name]) ||
			! is_a($this->_resource['filter'][$name], $class)) {
			
			// instantiate it
			$this->_resource['filter'][$name] =& new $class($conf);
			
			// add a Savant reference if requested
			if ($savantRef) {
				$this->_resource['filter'][$name]->Savant =& $this;
			}
			
		}
	}
	
	
	/**
	*
	* Unloads one or more filters from Savant2.
	*
	* @access public
	*
	* @param string|array $name The filter name (not including Savant2_Filter_
	* prefix).  If null, unloads all filters; if a string, unloads that one
	* filter; if an array, unloads all filters named as values in the array.
	*
	* @return void
	* 
	*/
	
	function unloadFilter($name = null)
	{
		if (is_null($name)) {
			$this->_resource['filter'] = array();
		} else {
			settype($name, 'array');
			foreach ($name as $key) {
				if (isset($this->_resource['filter'][$key])) {
					unset($this->_resource['filter'][$key]);
				}
			}
		}
	}
	
	
	/**
	*
	* Apply all loaded filters, in order, to text.
	*
	* @access public
	*
	* @param string $text The text to which filters should be applied. 
	* If null, sets the text to $this->_output.
	* 
	* @return string The text after being passed through all loded
	* filters.
	* 
	*/
	
	function applyFilters($text = null)
	{
		// set to output text if no text specified
		if (is_null($text)) {
			$text = $this->_output;
		}
		
		// get the list of filter names...
		$filter = array_keys($this->_resource['filter']);
		
		// ... and apply them each in turn.
		foreach ($filter as $name) {
			$this->_resource['filter'][$name]->filter($text);
		}
		
		// done
		return $text;
	}
	
	
	// -----------------------------------------------------------------
	//
	// Error handling
	//
	// -----------------------------------------------------------------
	
	
	/**
	*
	* Returns an error object.
	* 
	* @access public
	* 
	* @param int $code A SAVANT2_ERROR_* constant.
	* 
	* @param array $info An array of error-specific information.
	* 
	* @return object An error object of the type specified by
	* $this->_error.
	* 
	*/
	
	function &error($code, $info = array())
	{
		// the error config array
		$conf = array(
			'code' => $code,
			'text' => 'Savant2: ',
			'info' => (array) $info
		);
		
		// set an error message from the globals
		if (isset($GLOBALS['_SAVANT2']['error'][$code])) {
			$conf['text'] .= $GLOBALS['_SAVANT2']['error'][$code];
		} else {
			$conf['text'] .= '???';
		}
		
		// set up the error class name
		if ($this->_error) {
			$class = 'Savant2_Error_' . $this->_error;
		} else {
			$class = 'Savant2_Error';
		}

		// set up the error class file name
		$file = $class . '.php';
		
		// is it loaded?
		if (! $this->_classExists($class)) {
			
			// find the error class
			$result = $this->findFile('resource', $file);
			if (! $result) {
				// could not find the custom error class, revert to
				// Savant_Error base class.
				$class = 'Savant2_Error';
				$result = dirname(__FILE__) . '/Savant2/Error.php';
			}
			
			// include the error class
			include_once $result;
		}
		
		// instantiate and return the error class
		$err =& new $class($conf);
		return $err;
	}
	
	
	/**
	*
	* Tests if an object is of the Savant2_Error class.
	* 
	* @access public
	* 
	* @param object &$obj The object to be tested.
	* 
	* @return boolean True if $obj is an error object of the type
	* Savant2_Error, or is a subclass that Savant2_Error. False if not.
	*
	*/
	
	function isError(&$obj)
	{
		if (is_object($obj)) {
			if (is_a($obj, 'Savant2_Error') ||
				is_subclass_of($obj, 'Savant2_Error')) {
				return true;
			}
		}
		
		return false;
	}
}
?>