<?php

namespace app\components;

use ErrorException;
use Yii;
use yii\helpers\ArrayHelper;

/**
 * FUNCTION
 *		A class that is used to parse the XML content file.
 * USAGE
 *		Call setStartTime - sets the start time
 *		Call setXMLFile(filename) - set the filename of our XML file
 *		Call startParse - starts parsing the document and inserting the data in our
 *		MySQL database.
 * PROPERTIES
 *		The basic properties to get this class going:
 *		count_rows (@int):
 *			How many rows we have done so far
 *		count_rows_temp (@int):
 *			A temporary counter (--Reset after ECHO_STATS_FREQUENCY rows)
 *
 *		XML tags and their contents
 *		current_tag (@string):
 *			Hold what tag we currently are in
 *		permitted_tags (@array)
 *			An array that holds the permitted tags
 *
 *		Properties for the XML structure:
 *		-------
 *		CONTENT LINKS (content_links):
 *		topic (@string)
 *		type (@string)
 *		resource (@string)
 *		catid (@int)
 *
 *		CONTENT DESCRIPTION (content_description):
 *		external_page (@string)
 *		title (@string)
 *		description (@string)
 *		priority (@int)
 * METHODS
 *		startParse, _startTagProcessor, _endTagProcessor, _charDataProcessor
 ****/
class ContentParserComponent extends ParserComponent
{
    public $descriptions = [];
    public $links = [];

    public  $count_rows;
    public  $count_rows_temp;
    public  $current_tag;
    public  $permitted_tags;

//(content_links)
    public  $topic;
    public  $type;
    public  $resource;
    public  $catid;

//(content_description)
    public  $external_page;
    public  $title;
    public  $description;
    public  $priority;
    public  $ext_topic;

    public function startParse()
    {
        $this->printToConsole("Start parsing content.rdf.u8 file");

        $this->xml_file = 'data/content.rdf.u8';
        $this->setStartTime();
        //Starts with clean properties

        //(content_links)
        $this->topic = '';
        $this->type = '';
        $this->resource = '';

        //(content_description)
        $this->external_page = '';
        $this->title = '';
        $this->description = '';
        $this->priority = 0;
        $this->ext_topic = '';

        $this->current_tag = '';

        //Here we specify what tags are legal

        $this->permitted_tags = ['link', 'link1'];

        $this->_startToParse();

        //Print out that it is finished!
        $this->printToConsole("Finished processing content RDF file!");
        $this->printToConsole("Inserted rows into the database: $this->count_rows");
    }

    /**
     * Function that processes the start tags.
     * @param object $__parser What parser is it dude? heh
     * @param string $__tag_name The name of the current tagname
     * $param array $__attributes Attributes of the tag_name
     **/
    public function _startTagProcessor($__parser, $__tag_name, $__attributes)
    {

        //Sets what tag we currently are in
        $this->current_tag = $__tag_name;

        //Check if the current tag is topic
        if ($this->current_tag == 'Topic')
        {
            //Reset catid
            $this->catid = '';

            //If it's true get id
            $this->topic = $__attributes['r:id'];
        }

        //Check if the current tag is external page
        if (strtolower($this->current_tag) == 'externalpage')
        {
            //If it's true get id
            $this->external_page = $__attributes['about'];
        }

        //Check if the tag is equal to some of our permitted tags
        if (ArrayHelper::isIn(strtolower($this->current_tag), $this->permitted_tags))
        {
            //Set type to be equal with the name
            $this->type = $__tag_name;

            //Set the resource to be equal the resource found in the tag
            $this->resource = $__attributes['r:resource'];
        }
    }

    /**
     * This is our end tag processor.
     * @param object $__parser What parser is it dude? heh
     * @param string $__tag_name The name of the current tag name
     **/
    public function _endTagProcessor($__parser, $__tag_name)
    {
        $db = Yii::$app->db;

        //Check if the end tag is external_page
        if (strtolower($__tag_name) == 'externalpage')
        {
            if (strpos($this->topic, "Top/Science") === FALSE) return;

            $this->descriptions[] = [
                $this->external_page,
                trim($this->title),
                trim($this->description),
                $this->priority,
                $this->ext_topic,
            ];

            $this->count_rows++; //Count rows
            $this->count_rows_temp++; //Temporary count rows - used to make a milestone

            $this->external_page = '';
            $this->title = '';
            $this->description = '';
            $this->priority = 0;
            $this->ext_topic = '';
            $this->current_tag = '';

            if (count($this->descriptions) == $this->batchInsertRowsCount) {
                $db->createCommand()->batchInsert('content_description',
                    [
                        'externalpage',
                        'title',
                        'description',
                        'priority',
                        'topic'
                    ],
                    $this->descriptions
                )->execute();
                $this->descriptions = [];
            }


        }

        //Check if the end tag is in the range of permitted tags
        if (ArrayHelper::isIn(strtolower($__tag_name), $this->permitted_tags))
        {
            if (strpos($this->topic, "Top/Science") === FALSE) return;

            $this->links[] = [
                $this->catid,
                $this->topic,
                $this->type,
                $this->resource
            ];

            $this->count_rows++; //Count rows
            $this->count_rows_temp++; //Temporary count rows - used to make a milestone

            $this->type = '';
            $this->resource = '';
            $this->current_tag = '';

            if (count($this->links == $this->batchInsertRowsCount)) {
                $db->createCommand()->batchInsert(
                    'content_links',
                    [
                        'catid',
                        'topic',
                        'type',
                        'resource'
                    ],
                    $this->links
                )->execute();
                $this->links = [];
            }

        }

        //Check if the stats are set
        if (ECHO_STATS) {
            //Check if ECHO_STATS_FREQUENCY is reached
            if ($this->count_rows_temp == ECHO_STATS_FREQUENCY)
            {
                $this->count_rows_temp = 0;
                $this->_echoStatus($this->start_time, $this->count_rows, 'Yet another '.ECHO_STATS_FREQUENCY.' rows reached! - content RDF document');
            }
        }
    }


    public function _charDataProcessor($__parser, $__data)
    {
        //Checks if there is something between the tags
        if(trim($__data) != '')
        {
            //Finds out what kind of data it is
            switch($this->current_tag) {
                case 'catid':
                    $this->catid = $__data;
                    break;
                case 'd:Title':
                    $this->title = $__data;
                    break;
                case 'd:Description':
                    $this->description = $__data;
                    break;
                case 'priority':
                    $this->priority = $__data;
                    break;
                case 'topic':
                    $this->ext_topic = $__data;
                    break;
                default:
                    break;
            }
        }
    }
}