<?php

namespace buibr\xmlepg;

use XMLReader;
use SimpleXMLElement;
use RuntimeException;
use DateTimeZone;

class EpgParser {

    //	Source datas.
    private $file;
    private $url;
    private $content;
    //	for temporary file if from content or from url.
    private $isTemp;
    public $temp_dir = '/tmp'; //unix, change this for windows.
    //	channel settings
    private $channels;
    private $channels_groupby = '@id';
    //	programmes settings.
    private $epgdata;
    private $epgdata_groupby = '@id';
    //	filter
    private $channelfilter = [];
    private $ignoreDescr = [];
    //	zone.
    private $targetTimeZone;
    //	callbacks
    public $onError;

    public function __construct() {
        $this->targetTimeZone = \date_default_timezone_get();
    }

    /**
     * @param mixed $file`
     */
    public function setFile($file): void {
        $this->file = $file;
    }

    /**
     * @param mixed $url - url
     */
    public function setUrl($url): void {
        $this->url = $url;
    }

    /**
     * @param mixed $content = xml parsed string.
     */
    public function setContent($content): void {
        $this->content = $content;
    }

    /**
     * @param mixed $channelfilter
     */
    public function setChannelfilter($channelfilter): void {
        $this->channelfilter[$channelfilter] = 1;
    }

    /**
     * @param string $descr
     */
    public function setIgnoreDescr(string $descr): void {
        $this->ignoreDescr[$descr] = 1;
    }

    /**
     * @param mixed $targetTimeZone
     */
    public function setTargetTimeZone($targetTimeZone): void {
        $this->targetTimeZone = $targetTimeZone;
    }

    /**
     * Set group by for channels must be channels atribute.
     * @param $group - channel will be grouped with. must be @id or pgram attribute.
     */
    public function setChannelGroup($group) {
        $this->channels_groupby = $group;
    }

    /**
     * Set group by for channels must be channels atribute.
     * 	@id = array index starting from 0
     * @param $group - programes will be grouped with. must be @id or pgram attribute.
     */
    public function setProgrammGroup($group) {
        $this->epgdata_groupby = $group;
    }

    /**
     * Parse the date from string in posible formats.
     */
    public function getDate(string $date) {

        try {
            $dt = \DateTime::createFromFormat('YmdHis P', $date, new DateTimeZone('UTC'));
            $dt->setTimezone(new DateTimeZone($this->targetTimeZone));
            return $dt->format('Y-m-d H:i:s');
        } catch (\Exception $e) {

        } catch (\Error $e) {

        }

        try {
            $dt = \DateTime::createFromFormat('YmdHis', $date, new DateTimeZone('UTC'));
            $dt->setTimezone(new DateTimeZone($this->targetTimeZone));
            return $dt->format('Y-m-d H:i:s');
        } catch (\Exception $e) {

        } catch (\Error $e) {

        }


        try {
            $ex = explode(' ', $date);
            $sd = $ex[0];
            $ed = $ex[1];

            if (strlen($sd) == 13) {
                $sd = "{$sd}0";
            }

            $date = $sd . " " . $ed;

            $dt = \DateTime::createFromFormat('YmdHis P', $date, new DateTimeZone('UTC'));
            $dt->setTimezone(new DateTimeZone($this->targetTimeZone));
            return $dt->format('Y-m-d H:i:s');
        } catch (\Exception $e) {

        } catch (\Error $e) {

        }


        return null;
    }

    /**
     * @param $descr
     *
     * @return string
     */
    private function filterDescr($descr): string {
        if (array_key_exists($descr, $this->ignoreDescr)) {
            return '';
        }
        return $descr;
    }

    /**
     * @return mixed
     */
    public function getChannels() {
        return $this->channels;
    }

    /**
     * @return array
     */
    public function getEpgdata() {
        return $this->epgdata;
    }

    /**
     *
     */
    public function resetChannelfilter(): void {
        $this->channelfilter = [];
    }

    /**
     *
     */
    private function channelMatchFilter(string $channel): bool {
        return array_key_exists($channel, $this->channelfilter);
    }

    /**
     * @throws \RuntimeException
     * @throws \Exception
     */
    public function parseFile(): void {

        if (!$this->file) {
            throw new \RuntimeException('missing file: please use setFile before parse');
        }

        if (!file_exists($this->file)) {
            throw new \RuntimeException('file does not exists: ' . $this->file);
        }

        //
        $xml = new XMLReader();

        //	compress.zlib://'
        $xml->open($this->file);

        /** @noinspection PhpStatementHasEmptyBodyInspection */
        /** @noinspection LoopWhichDoesNotLoopInspection */
        /** @noinspection MissingOrEmptyGroupStatementInspection */
        while ($xml->read() && $xml->name !== 'channel') {

        }

        $i = 0;
        while ($xml->name === 'channel') {
            $element = new SimpleXMLElement($xml->readOuterXML());

            /** @noinspection	PhpUndefinedFieldInspection */
            $group_by = $this->channels_groupby === '@id' ? (@$i++) : (string) $element->attributes()->{$this->epgdata_groupby};

            //	se the id
            $channel_id = $group_by ?: 1;

            /** @noinspection PhpUndefinedFieldInspection */
            $this->channels[$channel_id] = [
                'id' => (string) $element->attributes()->id,
                'display-name' => (string) $element->{'display-name'},
                'url' => (string) $element->{'url'},
                'email' => (string) $element->{'email'},
                'icon' => null,
            ];
            if (isset($element->{'icon'}) && $element->{'icon'} instanceof SimpleXMLElement) {
                $attributes = $element->{'icon'}->attributes();
                $pathinfo = pathinfo($attributes->src);

                if (empty($attributes->src)) {
                    $this->channels[$channel_id]['icon'] = (string) $element->{'icon'};
                    $xml->next('channel');
                    unset($element);
                } elseif (!filter_var($attributes->src, FILTER_VALIDATE_URL)) {
                    $this->channels[$channel_id]['icon'] = (string) $element->{'icon'};
                    $xml->next('channel');
                    unset($element);
                } elseif (empty($pathinfo['extension'])) {
                    $this->channels[$channel_id]['icon'] = (string) $element->{'icon'};
                    $xml->next('channel');
                    unset($element);
                    continue;
                } else {
                    $this->channels[$channel_id]['icon'] = (string) $attributes->src;
                }
            }

            $xml->next('channel');
            unset($element);
        }

        $xml->close();
        $xml->open($this->file);

        /** @noinspection PhpStatementHasEmptyBodyInspection */
        /** @noinspection LoopWhichDoesNotLoopInspection */
        /** @noinspection MissingOrEmptyGroupStatementInspection */
        while ($xml->read() && $xml->name !== 'programme') {

        }

        while ($xml->name === 'programme') {
            $element = new SimpleXMLElement($xml->readOuterXML());

            /** @noinspection PhpUndefinedFieldInspection */
            if (!\count($this->channelfilter) || (\count($this->channelfilter) && $this->channelMatchFilter((string) $element->attributes()->channel))) {

                /** @noinspection 	PhpUndefinedFieldInspection */
                $startString = $this->getDate((string) $element->attributes()->start);

                /** @noinspection	PhpUndefinedFieldInspection */
                $stopString = $this->getDate((string) $element->attributes()->stop);

                /** @noinspection	PhpUndefinedFieldInspection */
                $grouper = $this->epgdata_groupby === '@id' ? (@$i++) : (string) $element->attributes()->{$this->epgdata_groupby};

                $icon = (string) $element->icon;
                if (empty($icon) && !empty($element->icon->attributes()->src)) {
                    $icon = (string) $element->icon->attributes()->src;
                }

                /** @noinspection PhpUndefinedFieldInspection */
                $this->epgdata[$grouper ?: 0] = [
                    'start' => $startString,
                    'start_raw' => (string) $element->attributes()->start,
                    'channel' => (string) $element->attributes()->channel,
                    'stop' => $stopString,
                    'title' => (string) $element->title,
                    'sub-title' => (string) $element->{'sub-title'},
                    'desc' => $this->filterDescr((string) $element->desc),
                    'date' => (int) (string) $element->date,
                    'category' => (string) $element->category,
                    'credits' => (string) $element->credits,
                    'country' => (string) $element->country,
                    'icon' => $icon,
                    'episode-num' => (string) $element->{'episode-num'},
                ];
            }

            $xml->next('programme');
            unset($element);
        }

        $xml->close();

        if ($this->isTemp) {
            @unlink($this->file);
        }
    }

    /**
     * @throws \RuntimeException
     * @throws \Exception
     */
    public function parseUrl(): void {

        if (!$this->url) {
            throw new \RuntimeException('Url missing: please use setUrl before parseUrl');
        }

        if (!filter_var($this->url, FILTER_VALIDATE_URL)) {
            throw new \RuntimeException('Url invalid: ' . $this->url);
        }

        $this->content = @\file_get_contents($this->url);

        if (!strpos($http_response_header[0], "200")) {
            throw new \RuntimeException("Invalid response headers: " . $http_response_header[0], 1);
        }

        $this->checkXml();
        $this->saveTemp(); // will save the file.
        $this->parseFile();
    }

    /**
     * @throws \RuntimeException
     * @throws \Exception
     */
    public function parseContent(): void {

        if (!$this->content) {
            throw new \RuntimeException('Url missing: please use setUrl before parseUrl');
        }

        $this->checkXml();
        $this->saveTemp(); // will save the file.
        $this->parseFile();
    }

    /**
     * Save content to temp file from ulr or from content.
     */
    public function saveTemp(): void {
        if (empty($this->temp_dir)) {
            $this->temp_dir = '/tmp/';
        }

        $length = 15;
        $filename = substr(str_shuffle(str_repeat($x = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ', ceil($length / strlen($x)))), 1, $length);

        $this->file = $this->temp_dir . '/' . $filename . '.xml';

        if (!\file_put_contents($this->file, $this->content)) {
            throw new \RuntimeException("Writing to {$this->file} is not possible.");
        }

        $this->isTemp = true;
        $this->content = null;
    }

    /**
     * Check content of response from xml f is xml
     * @throws \RuntimeException
     */
    public function checkXml() {
        libxml_use_internal_errors(true);
        $doc = simplexml_load_string($this->content);
        if (!$doc) {
            $errors = libxml_get_errors();
            @$errors = $errors[0];

            throw new \RuntimeException("Content of this request its not XML: $errors");
        }
    }
}