<?php



class IndexerComponent extends Object {



    /**

     * @var AppController

     */

    var $controller;



    /**

     * @var QueueComponent

     */

    var $Queue;



    /**

     * @var Index

     */

    var $Index;





    var $components = array('Queue');



    function initialize (&$controller, $settings = array()) {



        $this->controller =& $controller;



        $this->Index = ClassRegistry::init('Index');

    }



    private function _import()  {

        App::import('Vendor', 'html_to_text');

        App::import('Vendor','get_time_left');

        App::import('Vendor', 'resolve_url');

        App::import('Vendor', 'tsep_crawler');

        App::import('Vendor', 'tsep_indexer');

        App::import('Vendor', 'start_script');

        App::import('Vendor', 'random_string');

    }



    /**

     * _begin

     * Creates the indexer_running.tmp file

     */

    private function _begin() {



        register_shutdown_function(array($this, 'end'));



        $fp = @fopen(TMP.'indexer_running.tmp', 'w');

        @fclose($fp);

    }

    /**

     * _end

     * removes the indexer_running.tmp file

     */

    private function _end () {

        @unlink(TMP.'indexer_running.tmp');

    }





    /**

     * Helper function on PHP shutdown

     */

    function end () {

        $this->_end();

    }





    private function _singular () {

        if(!file_exists(TMP.'indexer_running.tmp')) {

            return true;

        }

        else {

            return false;

        }

    }



    private function _generateAuth () {



        App::import('Vendor', 'random_string');



        $randstr = random_string(10);



        file_put_contents(TMP.'auth.tmp', $randstr);



        return $randstr;



    }



    private function _verifyAuth ($auth_key) {



        $auth = @file_get_contents(TMP.'auth.tmp');



        if($auth_key != $auth) {



            return false;

        }

        else{



            @unlink(TMP.'auth.tmp');



            return true;

        }

    }





    private function _run () {



        if(!$this->_singular()) {

            $this->log('Singular; Indexing aborted');



            return false;

        }

        else {



            //Register the indexer is running

            $this->_begin();



            $this->log('Checking for jobs', LOG_INFO);



            if($this->Queue->isJob('indexer')) {



                $job = $this->Queue->getJob('indexer');



                $this->log('Job found; Processing Job');



                $new_job = $this->_index($job);



                if($new_job) {



                    $this->Queue->addJob($new_job['function_name'], $new_job['params'], 'indexer');

                }



                $this->_end();



                return $this->_generateAuth();



            }

            else {



                $this->log('No jobs found; aborting', LOG_INFO);



                $this->_end();



                return false;

            }

        }



    }









    /**

     * _index

     * Indexes the job given

     * @param array $job The Job to index

     * @return mixed false on completion, array job to be requeued on incompletion

     */

    private function _index($job) {



        $this->log('#0003 Initializing', LOG_INFO);



        if (empty($job)) {



            $this->log('Invalid Job given to indexer');

            return false;

        }



        $this->log('Loading framework');



        $id = $job['function_name'];





        if (!empty($job['params'])) {



            //We are resuming

            $this->log('Resuming from previous state');



            $indexer = $job['params']['indexer'];

            $crawler = $job['params']['crawler'];



        }

        else {



            //We are initializing

            $this->log('Loading dependancies', LOG_INFO);



            $profile = $this->Index->Profile->findById($id);



            if(empty($profile)) {



                $this->log('#0001 Invalid Profile Request; Indexing Failed.', LOG_ERROR);



                return false;

            }



            $stopwords = $this->Index->Profile->Stopword->find('all');



            //TODO: Specify a different user agent for ea. indexing profile



            $crawler = new TSEPCrawler($profile['Profile']['url'], $profile['Profile']['regex'], Configure::read('UserAgent'));

            $indexer = new TSEPIndexer($stopwords);



            $this->log('Deleting indexes');



            $this->Index->deleteAll(array('Index.profile_id' => $id), false);

        }



        $this->log('Beginning crawl');



        while ($page = $crawler->crawl()) {



            if($indexer->parse($page)) {



                $save = $this->Index->create(array(

                    'Index' => array(

                        'profile_id' => $id,

                        'url' => $page->url,

                        'text' => $page->content

                    )

                ));



                $this->log('Saving Page', LOG_INFO);

                $this->Index->save($save);



            }



            if (get_time_left() <= 10) {



                //Return job to be requeued

                return array(

                    'function_name' => $id,

                    'params' => array(

                        'crawler' => $crawler,

                        'indexer' => $indexer

                    )

                );

            }



        }



        $this->log('Indexing Complete');



        return false;

    }



    /**

     * Processes the Indexing Queue

     * @param string $auth_key The authorization key provided

     * @return mixed string on incompletion, false on completion

     */

    function processRequest ($auth_key) {



        $this->log('Processing Request');



        if (!$this->_verifyAuth($auth_key)) {



            $this->log('Authentication Failed', LOG_INFO);



            return false;

        }

        else {

            $this->log('Authentication Success', LOG_INFO);



            $this->_import();



            return $this->_run();

        }

    }



    /**

     * Submit an indexing request

     * @param string $id The profile to index

     * @return string the auth key

     */

    function submitRequest ($id) {



        $this->log('#0002 Request submitted', LOG_INFO);



        $this->Queue->addJob($id, array(), 'indexer');



        return $this->_generateAuth();

    }



}