JSend View Model

gistfile1.php

<?php defined('SYSPATH') or die('No direct script access.');
/**
 * Strict JSend response formatting
 *
 * @author	kemo <github.com/kemo>
 * @see		http://labs.omniti.com/labs/jsend
 */ 
class View_Ajax {

	// Release version
	const VERSION = '1.0.1';

	/**
	 * @var		Array of return data
	 */
	protected $_data = array(
		// Must-set
		'data'		=> array(),
		'status'	=> 'success',	// success, error
		
		// Optional, on error
		'code'		=> NULL,
		'message'	=> NULL,
	);
	
	/**
	 * @param	array	initial array of data
	 */
	public function __construct(array $data = NULL)
	{
		if (NULL !== $data)
		{
			$this->set($data);
		}
	}
	
	/**
	 * Magic getter method
	 */
	public function __get($key)
	{
		if (isset($this->_data[$key]))
		{
			return $this->_data[$key];
		}
		elseif (isset($this->_data['data'][$key]))
		{
			return $this->_data['data'][$key];
		}
		
		throw new Kohana_Exception('Nonexisting key requested: :key', array(
			':key' => $key
		));
	}
	
	/**
	 * Magic setter method
	 */
	public function __set($key, $value)
	{
		return $this->set($key, $value);
	}
	
	/**
	 * What happens when casted to string?
	 */
	public function __toString()
	{
		return $this->render();
	}
	
	/**
	 * Binds a param by reference
	 * 
	 * @param	string	key
	 * @param	mixed	var
	 * @return	object	$this
	 */
	public function bind($key, & $value)
	{
		if (isset($this->_data[$key]))
		{
			$this->validate($key, $value);
			
			$this->_data[$key] =& $value;
		}
		else
		{
			$this->_data['data'][$key] =& $value;
		}
		
		return $this;
	}
	
	/**
	 * @param	int		$code
	 * @return	mixed	$code on get / $this on set
	 */
	public function code($code = NULL)
	{
		if (NULL === $code)
			return $this->_data['code'];
		
		$this->_data['code'] = $code;
		
		return $this;
	}
	
	/**
	 * @param	string	$message
	 * @return	mixed	$message on get // $this on set
	 */
	public function message($message = NULL)
	{
		if (NULL === $message)
			return $this->_data['message'];
		
		$this->_data['message'] = $message;
		
		return $this;
	}
	
	/**
	 * Renders the current dataset
	 * @return	string	JSON encoded data
	 */
	public function render()
	{
		foreach ($this->_data as $key => $value)
		{
			// Unset empty params
			if (NULL === $this->_data[$key])
			{
				unset($this->_data[$key]);
			}
		}
		
		return json_encode($this->_data);
	}
	
	/**
	 * Sets a key => value pair or an array of values
	 * 
	 * @chainable
	 * @param	mixed	string key or array of key => value pairs
	 * @param	mixed	value
	 * @return	object	$this
	 */
	public function set($key, $value = NULL)
	{
		if (is_array($key))
		{
			foreach ($key as $name => $value)
			{
				$this->set($name, $value);
			}
			
			return $this;
		}
		elseif (isset($this->_data[$key]))
		{
			$this->validate($key, $value);
			
			$this->_data[$key] = $value;
		}
		else
		{
			$this->_data['data'][$key] = $value;
		}
		
		return $this;
	}
	
	/**
	 * @param	string	$status
	 * @return	mixed	$status on get // $this on set
	 */
	public function status($status = NULL)
	{
		if (NULL === $status)
			return $this->_data['status'];
		
		if ( ! in_array($status, array('error','success')))
			throw new Kohana_Exception('Status must be error or success');
				
		$this->_data['status'] = $status;
		
		return $this;
	}
	
	/**
	 * Validates the data type of var being set
	 * 
	 * @param	string	key being set
	 * @param	mixed	value being set
	 * @return	bool	TRUE if passed, exception thrown otherwise
	 * @throws	Kohana_Exception
	 */
	public function validate($key, $value)
	{
		// Validate data types
		switch ($key)
		{
			case 'data' :
				
				if ( ! is_array($value))
					throw new Kohana_Exception('`data` param must be an array');
				
			break;
		}
		
		return TRUE;
	}
}