<?php 
/**
 * Pagination Component, responsible for managing the DATA required for pagination.
 */
class PaginationComponent extends Object
{
    // Configuration/Default variables
/**
 * Specify whether the component will use AJAX links if available.
 * Tests for the presence of the RequestHandler component and if present will generate
 * AJAX links. However, if the prototype library js has not been included, normal updates
 * will take place.
 *
 * @var boolean
 * @access public
 */
	var $ajaxAutoDetect = true;
/**
 * Specify the div to update if using ajax updates
 *
 * @var string
 * @access public
 */
	var $ajaxDivUpdate = "content";
/**
 * The id of a form ID to be submitted with all pagination ajax links.
 *
 * @var string
 * @access public
 */
	var $ajaxFormId = NULL;
/**
 * Specify link style
 *
 * @var string "html"/"ajax"
 * @access public
 */
	var $style = "html";
/**
 * Specify link parameter style
 *
 * @var string "get"/"pretty"
 * @access public
 */
	var $paramStyle = "get";
/**
 * Used only for pretty style urls - must match the 
 *
 * @var string "get"/"pretty"
 * @access public
 */
	var $paramSeperator = "/";
/**
 * Specify DEFAULT start page number
 *
 * @var integer
 * @access public
 */
	var $page = 1;
/**
 * Specify DEFAULT number of items to be displayed per page. Also used as the limit
 * for the subsequent SQL search.
 *
 * @var integer
 * @access public
 */
	var $show = 5;
/**
 * Specify DEFAULT sort column.
 *
 * @var string
 * @access public
 */
	var $sortBy = 'id';
/**
 * Specify DEFAULT sort direction.
 *
 * @var string
 * @access public
 */
	var $direction = 'ASC';
/**
 * Specify the maximum number of pages to be included in the list of pages. Should be an odd number, otherwise rounded down.
 *
 * @var integer
 * @access public
 */
    var $maxPages = 10;
/**
 * Options for results per page.
 *
 * @var array
 * @access public
 */
    var $resultsPerPage = array(2,5,10,20,50,100,500);
/**
 * Show links to the first and last page, if the number of pages exceeds the maxPage count.
 *
 * @var boolean
 * @access public
 */
	var $showLimits = true;
/**
 * An array of parameter names which cannot be specified by the url
 *
 * @var array
 * @access public
 */
	var $privateParams = Array();

    // Do not edit below this line unless you wish to customize the core functionality of this Component
/**
 * Place holder for the sort class. Irrelavent for models without associations
 *
 * @var boolean
 * @access private
 */
	var $sortByClass = NULL;
/**
 * Place holder for the model class.
 *
 * @var boolean
 * @access private
 */
	var $modelClass = NULL;
/**
 * Place holder for the base url
 *
 * @var boolean
 * @access private
 */
	var $url = NULL;
/**
 * Place holder for the controller
 *
 * @var boolean
 * @access private
 */
    var $controller = true;
/**
 * Place holder for the sanitize object
 *
 * @var boolean
 * @access private
 */
	var $sanitize = true;
/**
 * Place holder for the data array passed to the view
 *
 * @var boolean
 * @access private
 */
	var $paging;

/**
 * Startup - Link the component to the controller.
 *
 * @param controller
 */
    function startup(&$controller)
    {
		$this->controller =& $controller;    	
    }
/**
 * Initialize the pagination data.
 *
 * @param unknown
 * @param array
 * @options array
 * @return array
 */
    function init($criteria=NULL,$parameters=Array(),$options=Array())
    {
		uses('sanitize');
		$this->Sanitize = &new Sanitize;

		$this->_initFields($options);
		$this->_checkAjax();
		$this->_initSort();
		$this->_initPaging($parameters);
		$this->_initURL();

		$this->_setParameter("show",$parameters);
		// If the number of results per page isn't in the list, reset to default
		if ((isset($this->paging["show"]))&&(!in_array($this->paging["show"],$this->resultsPerPage)))
		{
			$this->paging["show"]=$this->paging['Defaults']['show'];
		}
		
		$this->_setParameter("page",$parameters);
		$this->_setParameter("sortBy",$parameters);
		$this->_setParameter("sortByClass",$parameters); // Overriding the model class if specified.
		$this->_setParameter("direction",$parameters);

		$this->_check4Form();

		$this->_setPrivateParameter("ajaxDivUpdate");
		$this->_setPrivateParameter("ajaxFormId");
		$this->_setPrivateParameter("maxPages");
		$this->_setPrivateParameter("showLimits");
		$this->_setPrivateParameter("style");
		$this->_setPrivateParameter("paramStyle");
		$this->_setPrivateParameter("paramSeperator");
		$this->_setPrivateParameter("url");

		if (isset($this->total)) // If the field is already set, we  passed in the options the total number of results
		{
			$count = $this->total;
		}
		else
		{
			$count = $this->controller->{$this->modelClass}->findCount($criteria,0);	
		}
		$this->checkPage($count);
		$this->paging['total'] = $count;
		$this->trimResultsPerPage($count);

		$this->_setPrivateParameter("resultsPerPage");

    	$this->paging['pageCount'] = ceil($count / $this->paging['show'] );

    	$this->controller->set('paging',$this->paging);
    	
        $this->order = $this->paging['sortByClass'].".".$this->paging['sortBy'].' '.strtoupper($this->paging['direction']);
        
    	// For backwards compatability & clarity
    	$this->limit = $this->paging['show'];
    	$this->page = $this->paging['page'];
    	
    	// For less code in the calling method..
    	return (Array($this->order,$this->paging['show'],$this->paging['page']));
	}
	
/**
 * Don't give the choice to display pages with no results
 *
 * @param integer
 */
    function trimResultsPerPage ($count = 0)
    {
        while (($limit = current($this->resultsPerPage))&&(!isset($capKey))) 
        {
            if ($limit >= $count) 
            {
                $capKey = key($this->resultsPerPage);
            }
        	next($this->resultsPerPage);
        
	        if (isset($capKey))
        	{
            	array_splice($this->resultsPerPage, ($capKey+1));
            }
        }
    }

/**
 * Set the page to the last if there would be no results, and to 1 if a negetive
 * page number is specified
 *
 * @param integer
 */
    function checkPage ($count = 0) 
    {
      if ((($this->paging['page']-1)*$this->paging['show'])>=$count) 
      {
            $this->paging['page'] = floor($count/$this->paging['show']+0.99);
      }
    }
	
/**
 * Set Object fields
 *
 * @param unknown
 */
	function _initFields($options)
	{
		foreach($options as $option=>$val)
		{
			$this->$option = $val;
		}
	}
/**
 * Set Pagination with default Parameters
 *
 * @param unknown
 */
	function _initPaging($parameters)
	{
		$this->paging['importParams']=$parameters;
		$this->paging['Defaults'] = Array (
										"page"=>$this->page,
										"show"=>$this->show,
										"sortBy"=>$this->sortBy,
										"sortByClass"=>$this->sortByClass,
										"direction"=>$this->direction
											);		
	}
/**
 * If everything is in place, use Ajax by default
 *
 * @param unknown
 */
	function _checkAjax()
	{
		if (($this->ajaxAutoDetect==true)&&(isset($this->controller->RequestHandler)&&(in_array("Ajax",$this->controller->helpers))))
		{
			$this->style = "ajax";			
		}
	}

/**
 * Set the DEFAULT sort class
 *
 * @param unknown
 */
	function _initSort()
	{
		if (!$this->modelClass)
		{
		    $ModelClass = $this->modelClass = $this->controller->modelClass;
		}
		else
		{
			$ModelClass = $this->modelClass;
		}
		if (!$this->sortBy)
		{
		$this->sortBy = $this->controller->$ModelClass->primaryKey;
		}
		if (!$this->sortByClass)
		{
			$this->sortByClass = $ModelClass;
		}
	}

/**
 * Set the base url for updates.
 *
 * @param unknown
 */
	function _initURL()
	{
		if ($this->url) // A url was specified in the paramters
		{
			if (substr($this->url, -1, 1)<>"/")
			{
				$this->url .= "/";
			}
		}
		else // No url in the parameters, derive it.
		{
			if ($this->paramStyle=="get")
			{
				$this->url = str_replace($this->controller->webroot,"/",$this->controller->here);
			}
			else
			{
				$this->url = "";
				if (isset($this->controller->params['admin']))
				{
					$this->url .= "/".$this->controller->params['admin'];
					$action = substr($this->controller->action, strlen($this->controller->params['admin']."_"));
				}
				else
				{
					$action = $this->controller->action;
				}
				if ($this->controller->plugin)
				{
					$this->url .= "/".$this->controller->plugin;
				}
				$this->url .= "/".$this->controller->name;
				$this->url .= "/".$action;
				if (isset($this->paging['importParams']['_unamedParameters']))
				{
					$unnamedString = implode ("/", $this->paging['importParams']['_unamedParameters']);
					$this->url .= "/".$unnamedString;
					unset($this->paging['importParams']['_unamedParameters']);
				}
				$this->url .= "/";
			}
		}
		if (defined('BASE_URL')) { // Hack for no mod_rewrite
			$this->url = preg_replace( "!".BASE_URL."!", '', $this->url); // Remove the base from the url
			$this->url = preg_replace("!\?.*!", '', $this->url); // Remove the get parameters
		}
	}

/**
 * If the parameters have been changed/set by a form action, update the params array.
 * Would perhaps be best to redirect to the equivalent url, which isn't implemented as
 * the relavent method is in the helper and as such inaccessible here.
 *
 * @param unknown
 */
	function _check4Form()
	{
		if(isset($this->controller->data['pagination']))
		{
			if (isset($this->controller->data['pagination']['sortByComposite']))
			{
				$Composite = Array();
				$Composite = explode("::",$this->controller->data['pagination']['sortByComposite']);
				if (isset($Composite[0]))
				{
					$this->controller->data['pagination']['sortBy'] = $Composite[0];	
				}
				if (isset($Composite[1]))
				{
					$this->controller->data['pagination']['direction'] = $Composite[1];	
				}
				if (isset($Composite[2]))
				{
					$this->controller->data['pagination']['sortByClass'] = $Composite[2];	
				}
				else
				{
					$this->controller->data['pagination']['sortByClass'] = $this->paging['Defaults']['sortByClass'];
				}
				unset($this->controller->data['pagination']['sortByComposite']);			
			}
			foreach($this->controller->data['pagination'] as $parameter=>$value)
			{
				
				if (!in_array($parameter, $this->privateParams))
				{
					$this->paging[$parameter] = $this->Sanitize->paranoid($value,array("-","_"));
				}				
			}
		}
	}

/**
 * Set a parameter to be passed to the view which cannot be specified/overriden from the url.
 *
 * @param unknown
 */
	function _setPrivateParameter($parameter)
	{
		$this->paging[$parameter]= $this->$parameter;
	}

/**
 * Set a parameter to be passed to the view overriden from the url if present.
 *
 * @param unknown
 * @param array
 * @param field
 */
	function _setParameter($parameter,$parameters=Array(),$field=NULL)
	{
		$field = $field?$field:$parameter;

		if (in_array($parameter, $this->privateParams))
		{
			$this->paging[$field] = $this->paging['Defaults'][$field];
		}
		else
		{
			if ($this->paramStyle=="get")
			{
				if (isset($_GET[$parameter]))
				{
					$this->paging[$field] = $this->Sanitize->paranoid($_GET[$parameter],array("-","_"));		
				}
				else
				{
					$this->paging[$field]= $this->$field;
				}
			}
			elseif ($this->paramStyle=="pretty")
			{
				if (isset($parameters[$parameter]))
				{
					$this->paging[$field] = $this->Sanitize->paranoid($parameters[$parameter],array("-","_"));		
				}
				else
				{
					$this->paging[$field]= $this->$field;
				}
			}
			else
			{
				echo ("parameter error");
				die;
			}
		}
	}
}
?>