<?php
/**
 * Datasource renderer JSON
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package WB
 * @subpackage db
 */

WBClass::load('WBDatasource_Renderer');

/**
 * Datasource renderer JSON
 *
 * @version 1.0.0
 * @package WB
 * @subpackage db
 */
class WBDatasource_Renderer_JSON extends WBDatasource_Renderer
{
    /**
     * Configuration parameters
     */
    protected $config   =   array(
                                    'addbom'    =>  0
                                    );


    /**
     * temporary file
     * @var WBFile
     */
    protected $file;

    /**
     * current file stream
     * @var resource
     */
    protected $stream;

    /**
     * cleanup
     *
     * remove temporary file
     */
    public function __destruct()
    {
        if ($this->file) {
            $this->file->unlink();
        }
    }

    /**
     * start rendering
     *
     * Open stream to render view
     */
    public function start($view)
    {
        $this->config['addbom'] =   intval($this->config['addbom']);

        if ($this->file) {
            $this->file->unlink();
        }
        $this->file =   WBClass::create('WBFile');
        $this->file->mkdir('var/tmp');
        $this->file->tempnam('json');
    }

    /**
     * render single item
     *
     * The consumer for data source iteratrion
     * @param array $item
     */
    public function renderItem($item)
    {
        $json   =   json_encode($item);

        // Append
        if ($this->stream) {
            fputs($this->stream, ",\n");
            fputs($this->stream, $json);
            return;
        }

        // Init file
        $this->stream   =   fopen($this->file->realpath(), 'w');
        fputs($this->stream, "[\n");
        if ($this->config['addbom']) {
            fputs($this->stream, "\xEF\xBB\xBF");
        }
        fputs($this->stream, $json);
    }

    /**
     * finish rendering
     *
     * Things to do after iterating through datasource
     */
    public function end()
    {
        if (!$this->stream) {
            return;
        }
        fputs($this->stream, "\n]\n");
        fclose($this->stream);
        $this->stream   =   null;
    }

    /**
     * get actual file
     *
     * @return WBFile
     */
    public function getFile()
    {
        return $this->file;
    }
}