<?php

/*
 * Copyright (C) 2007-2017	Andre Beckedorf
 * 				<evilJazz _AT_ katastrophos _DOT_ net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

define("CACHE_SQLITE_FILE", "./data/cache.db");
define("CACHE_EXPIRY_SECONDS", 30 * 24 * 60 * 60); // 30 days...

function fetchfile($URL, &$effectiveURL)
{
        $c = curl_init();
        curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($c, CURLOPT_URL, $URL);
        curl_setopt($c, CURLOPT_ENCODING, "gzip");
        curl_setopt($c, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($c, CURLOPT_USERAGENT, "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:40.0) Gecko/20100101 Firefox/40.0"); // YEP.
        $contents = curl_exec($c);
        $effectiveURL = curl_getinfo($c, CURLINFO_EFFECTIVE_URL);
        curl_close($c);

        if ($contents)
                return $contents;
        else
                return FALSE;
}

class CoverArtResult
{
        var $title;
        var $detailsURL;
        var $thumbnailImageURL;
        var $imageURL;
}

abstract class AbstractCoverArtProvider
{
        abstract public function getCoverArtList($artist, $album, $limit = 0);

        public function getCoverArtImage($artist, $album)
        {
                $coverArtList = $this->getCoverArtList($artist, $album, 1);
                $result = array();
                $this->tryDownloadImage($result, $coverArtList->items, 'image/jpeg');
                return $result;
        }

        public function name()
        {
                return get_class($this);
        }

        protected function getHTMLDom($url)
        {
                $startTime = microtime(true);

                $dom = new DomDocument();
                $effectiveURL = $url;
                $html = fetchfile($url, $effectiveURL);

                $htmlLoaded = @$dom->loadHTML($html);

                $endTime = microtime(true);
                $fetchTime = $endTime - $startTime;

                $result->dom = $dom;
                //$result->html = $html;
                $result->details['fetchTime'] = $fetchTime;
                $result->details['url'] = $url;
                $result->details['effectiveURL'] = $effectiveURL;
                $result->loaded = $htmlLoaded;

                return $result;
        }

        protected function getDOMNodesByXPath($dom, $xpath, $limit = 0, $xpathStopCondition = "")
        {
                $stopEval = false;

                $result->items = array();

                $result->details['xpath'] = $xpath;
                if (!empty($xpathStopCondition))
                        $result->details['xpathStopCondition'] = $xpathStopCondition;

                if (isset($dom->dom))
                        $domDoc = $dom->dom;
                else if (is_subclass_of($dom, "DOMNode"))
                {
                        $domDoc = $dom->ownerDocument;
                        $domNode = $dom;
                }
                else
                        $domDoc = NULL;

                if (!is_null($domDoc))
                {
                        $xp = new DomXPath($domDoc);
                        $stopEval = false;

                        if (!empty($xpathStopCondition))
                        {
                                if (isset($domNode))
                                        $items = $xp->evaluate($xpathStopCondition, $domNode);
                                else
                                        $items = $xp->evaluate($xpathStopCondition);

                                $stopEval = $items->length > 0;
                                $result->details['xpathStopConditionMatched'] = $stopEval;
                        }

                        if (!$stopEval)
                        {
                                $startTime = microtime(true);

                                if (isset($domNode))
                                        $items = $xp->evaluate($xpath, $domNode);
                                else
                                        $items = $xp->evaluate($xpath);

                                if (is_object($items))
                                {
                                        $i = 0;
                                        foreach ($items as $item)
                                        {
                                                $result->items[] = $item;
                                                ++$i;

                                                if ($limit > 0 && $i == $limit)
                                                        break;
                                        }
                                }
                                else if (!empty($items))
                                        $result->items[] = $items;

                                $count = count($result->items);

                                $endTime = microtime(true);
                                $evalTime = $endTime - $startTime;
                                $result->details['evalTime'] = $evalTime;
                        }
                }

                return $result;
        }

        protected function getListByXPath($dom, $xpath, $limit = 0, $xpathStopCondition = "", $invalidItemFilter = "")
        {
                $result = $this->getDOMNodesByXPath($dom, $xpath, $limit, $xpathStopCondition);
                $list = array();

                foreach ($result->items as $item)
                {
                        if (is_object($item))
                                $item = $item->nodeValue;

                        if (!empty($item) && $item != $invalidItemFilter)
                                $list[] = $item;
                }

                $result->items = $list;

                return $result;
        }

        protected function tryDownloadImage(&$result, $imageURLs, $mimetype = 'image/jpeg')
        {
                $result['success'] = false;

                if (count($imageURLs) > 0)
                {
                        $imageData = false;
                        $i = 0;
                        while ($imageData === false && $i < count($imageURLs))
                        {
                                $imageData = fetchfile($imageURLs[$i]);
                                ++$i;
                        }

                        if ($imageData)
                        {
                                $result['imagedata'] = $imageData;
                                $result['mimetype'] = $mimetype;
                                $result['success'] = true;
                        }
                }
        }
}

class CoverArtProviderAmazon extends AbstractCoverArtProvider
{
        private $topLevelDomain;

        function __construct($topLevelDomain = "com")
        {
                $this->topLevelDomain = $topLevelDomain;
        }

        public function name()
        {
                return AbstractCoverArtProvider::name() . "_" . $this->topLevelDomain;
        }

        public function getCoverArtList($artist, $album, $limit = 0)
        {
                $list->results = array();

                $dom = $this->getHTMLDom('http://www.amazon.' . $this->topLevelDomain . '/gp/search/?search-alias=popular&unfiltered=1&sort=salesrank&field-keywords=&field-artist=' . urlencode($artist) . '&field-title=' . urlencode($album));
                $list->details[] = $dom->details;

                $resultNodes = $this->getDOMNodesByXPath(
                        $dom,
                        '//div[@id="atfResults" or @id="btfResults"]//li[starts-with(@id, "result_") and contains(.//img/@class, "s-access-image") and not(contains(.//img/@src, "no-img-"))]',
                        $limit
                );
                $list->details[] = $resultNodes;

                foreach ($resultNodes->items as $resultNode)
                {
                        $titleList = $this->getListByXPath($resultNode, './/a[contains(@class, "s-access-detail-page")]/@title'); $list->details[] = $titleList;
                        $detailsList = $this->getListByXPath($resultNode, './/a[contains(@class, "s-access-detail-page")]/@href'); $list->details[] = $detailsList;
                        $thumbnailImageList = $this->getListByXPath($resultNode, './/img[contains(@class, "s-access-image")]/@src'); $list->details[] = $thumbnailImageList;

                        $coverArtItem = new CoverArtResult();
                        $coverArtItem->title = $titleList->items[0];
                        $coverArtItem->detailsURL = $detailsList->items[0];
                        $coverArtItem->thumbnailImageURL = $thumbnailImageList->items[0];
                        $coverArtItem->imageURL = preg_replace("/\._.*?\.jpg/", ".jpg", $coverArtItem->thumbnailImageURL); // Replace ._AA160_.jpg with .jpg

                        if ($coverArtItem->thumbnailImageURL != "" && $coverArtItem->imageURL != "")
                            $list->results[] = $coverArtItem;
                }

                return $list;
        }
}

class CoverArtProviderGoogleImages extends AbstractCoverArtProvider
{
        private $topLevelDomain;

        function __construct($topLevelDomain = "com")
        {
                $this->topLevelDomain = $topLevelDomain;
        }

        public function name()
        {
                return AbstractCoverArtProvider::name() . "_" . $this->topLevelDomain;
        }

        public function getCoverArtList($artist, $album, $limit = 0)
        {
                $list->results = array();

                // tbm=isch -> We want image search
                // tbs=isz:l -> We want large images
                $dom = $this->getHTMLDom('http://www.google.' . $this->topLevelDomain . '/search?tbm=isch&tbs=isz:l&q=Album+%22' . urlencode($artist) . '%22+%22' . urlencode($album) . '%22');
                $list->details[] = $dom->details;

                $resultNodes = $this->getDOMNodesByXPath($dom, '//div[@id="rg_s"]//div[contains(@class,"rg_di")]', $limit);
                $list->details[] = $resultNodes;

                foreach ($resultNodes->items as $resultNode)
                {
                        $metaList = $this->getListByXPath($resultNode, './/div[contains(@class,"rg_meta")]/text()'); $list->details[] = $metaList;

                        $coverArtItem = new CoverArtResult();

                        // Get metadata from rg_meta JSON payload...
                        $meta = json_decode($metaList->items[0]);
                        
                        $coverArtItem->title = $meta->pt;
                        $coverArtItem->detailsURL = $meta->ru;
                        $coverArtItem->imageURL = $meta->ou;
                        $coverArtItem->thumbnailImageURL = $meta->tu;

                        if ($coverArtItem->thumbnailImageURL != "" && $coverArtItem->imageURL != "")
                            $list->results[] = $coverArtItem;
                }

                return $list;
        }
}

class CoverArtProviderLastFM extends AbstractCoverArtProvider
{
        public function getCoverArtList($artist, $album, $limit = 0)
        {
                $list->results = array();

                $detailURL = 'http://www.lastfm.com/music/' . urlencode($artist) . '/' . urlencode($album);

                $dom = $this->getHTMLDom($detailURL);

                $list->details[] = $dom;

                $resultNodes = $this->getDOMNodesByXPath($dom, '/html[.//img[@class="cover-art"]]', $limit);
                $list->details[] = $resultNodes;

                foreach ($resultNodes->items as $resultNode)
                {
                        $imageList = $this->getListByXPath($resultNode, '//img[@class="cover-art"]/@src'); $list->details[] = $imageList;
                        $titleList = $this->getListByXPath($resultNode, '//img[@class="cover-art"]/@alt'); $list->details[] = $titleList;
                        $thumbnailImageList = $imageList;

                        $coverArtItem = new CoverArtResult();
                        $coverArtItem->title = utf8_decode($titleList->items[0]);
                        $coverArtItem->detailsURL = $detailURL;
                        $coverArtItem->thumbnailImageURL = $thumbnailImageList->items[0];
                        $coverArtItem->imageURL = str_replace("/u/174s/", "/u/", $imageList->items[0]);

                        if ($coverArtItem->thumbnailImageURL != "" &&
                            $coverArtItem->imageURL != "" &&
                            stristr($coverArtItem->thumbnailImageURL, "c6f59c1e5e7240a4c0d427abd71f3dbb") === FALSE && // Placeholder image, probably hash
                            stristr($coverArtItem->imageURL, "c6f59c1e5e7240a4c0d427abd71f3dbb") === FALSE &&
                            stristr($coverArtItem->thumbnailImageURL, "noimage") === FALSE &&
                            stristr($coverArtItem->imageURL, "noimage") === FALSE)
                            $list->results[] = $coverArtItem;
                }

                return $list;
        }
}

class CoverArtProviderCache extends AbstractCoverArtProvider
{
        private $coverArtProviders;
        private $coverArtProviderQueryLimit;
        private $dbh;
        private $selectStmt;
        private $insertSearchStmt;
        private $insertResultStmt;

        function __construct($coverArtProviders = NULL, $coverArtProviderQueryLimit = 0)
        {
                if (is_null($coverArtProviders))
                {
                        global $globalCoverArtProviders;
                        $coverArtProviders = $globalCoverArtProviders;
                }

                $this->coverArtProviders = $coverArtProviders;
                $this->coverArtProviderQueryLimit = $coverArtProviderQueryLimit;

                $createDB = !file_exists(CACHE_SQLITE_FILE);

            $this->dbh = new PDO('sqlite:' . CACHE_SQLITE_FILE);

            if ($createDB)
            {
                $this->dbh->exec('
                                CREATE TABLE "searches" (
                                        "search_id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
                                        "provider_name" TEXT NOT NULL COLLATE NOCASE,
                                        "artist" TEXT NOT NULL COLLATE NOCASE,
                                        "album" TEXT NOT NULL COLLATE NOCASE,
                                        "timestamp" INTEGER NOT NULL
                                );

                                CREATE TABLE "searches_results" (
                                    "result_id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
                                        "search_id" INTEGER,
                                        "index" INTEGER NOT NULL,
                                        "title" TEXT NOT NULL,
                                        "details_url" TEXT NOT NULL,
                                        "thumbnail_image_url" TEXT NOT NULL,
                                        "image_url" TEXT NOT NULL
                                );

                                CREATE INDEX "searches_provider_name" on searches (provider_name ASC);
                                CREATE INDEX "searches_artist" on searches (artist ASC);
                                CREATE INDEX "searches_album" on searches (album ASC);
                                CREATE INDEX "searches_results_search_id" on searches_results (search_id ASC);

                                CREATE TRIGGER delete_searches_results DELETE ON searches
                                BEGIN
                                        DELETE FROM searches_results WHERE search_id = OLD.search_id;
                                END;
                ');
            }

                $this->selectStmt = $this->dbh->prepare(
                        "SELECT * FROM searches " .
                        "LEFT JOIN searches_results AS sr ON sr.search_id = searches.search_id " .
                        "WHERE provider_name = ? AND artist = ? AND album = ? ORDER BY `index`;"
                );

                if (!$this->selectStmt)
                {
                    echo "\nPDO::errorInfo():\n";
                    print_r($this->dbh->errorInfo());
                }

                $this->insertSearchStmt = $this->dbh->prepare(
                        "INSERT INTO searches (search_id, provider_name, artist, album, timestamp) " .
                        "VALUES (NULL, ?, ?, ?, ?);"
                );

                if (!$this->insertSearchStmt)
                {
                    echo "\nPDO::errorInfo():\n";
                    print_r($this->dbh->errorInfo());
                }

                $this->insertResultStmt = $this->dbh->prepare(
                        "INSERT INTO searches_results (result_id, search_id, `index`, title, details_url, thumbnail_image_url, image_url) " .
                        "VALUES (NULL, ?, ?, ?, ?, ?, ?);"
                );

                if (!$this->insertResultStmt)
                {
                    echo "\nPDO::errorInfo():\n";
                    print_r($this->dbh->errorInfo());
                }
        }

        public function getCoverArtList($artist, $album, $limit = 0)
        {
                $listLimit = $limit;
                $list->results = array();

                $coverArtProviderQueried = 0;

                foreach ($this->coverArtProviders as $provider)
                {
                        $success = $this->selectStmt->execute(array($provider->name(), $artist, $album));
                        $rows = $this->selectStmt->fetchAll();
                        $resultsValid = false;

                        if ($success && count($rows) > 0)
                        {
                                $resultsValid = $rows[0]["timestamp"] > time() - CACHE_EXPIRY_SECONDS;
                                if (!$resultsValid)
                                {
                                        //echo "Cached results expired, removing " . $rows[0][0];
                                        $this->dbh->exec("DELETE FROM searches WHERE search_id = " . $rows[0][0] . ";");
                                }
                        }

                        if ($resultsValid)
                        {
                                //echo "Something was found in the cache...";
                                $coverArtList->results = array();

                                foreach ($rows as $row)
                                {
                                        if (is_null($row["image_url"]))
                                                break;

                                        $coverArtItem = new CoverArtResult();
                                        $coverArtItem->title = $row["title"];
                                        $coverArtItem->detailsURL = $row["details_url"];
                                        $coverArtItem->thumbnailImageURL = $row["thumbnail_image_url"];
                                        $coverArtItem->imageURL = $row["image_url"];

                                        if ($coverArtItem->thumbnailImageURL != "" && $coverArtItem->imageURL != "")
                                            $coverArtList->results[] = $coverArtItem;

                                        if ($limit > 0 && count($coverArtList->results) == $listLimit)
                                                break;
                                }
                        }
                        else
                        {
                                //echo "Nothing found in the cache...";
                                $coverArtList = $provider->getCoverArtList($artist, $album, $listLimit);

                                $this->dbh->beginTransaction();

                                if ($this->insertSearchStmt->execute(array($provider->name(), $artist, $album, time())))
                                {
                                        $searchID = $this->dbh->lastInsertId();
                                        //echo "Search inserted: " . $searchID;

                                        foreach ($coverArtList->results as $index => $result)
                                        {
                                                $this->insertResultStmt->execute(array(
                                                        $searchID,
                                                        $index,
                                                        $result->title,
                                                        $result->detailsURL,
                                                        $result->thumbnailImageURL,
                                                        $result->imageURL
                                                ));
                                        }
                                }

                                $this->dbh->commit();
                        }

                        $list->results = array_merge($list->results, $coverArtList->results);

                        if ($limit > 0)
                        {
                                $listLimit = max(0, $listLimit - count($coverArtList->results));
                                if ($listLimit == 0)
                                        break;
                        }

                        if (count($coverArtList->results) > 0)
                                ++$coverArtProviderQueried;

                        if ($this->coverArtProviderQueryLimit > 0 &&
                                count($coverArtList->results) > 0 &&
                                $coverArtProviderQueried == $this->coverArtProviderQueryLimit)
                                break;
                }

                return $list;
        }
}

$globalCoverArtProviders = array(
        new CoverArtProviderLastFM(),
        new CoverArtProviderGoogleImages("de"),
        new CoverArtProviderGoogleImages("com"),
        new CoverArtProviderAmazon("de"),
        new CoverArtProviderAmazon("com")
);

function getCoverArtResults($artist, $album, $limit = 0, $coverArtProviders = NULL)
{
        $results = array();
        $listLimit = $limit;

        if (is_null($coverArtProviders))
        {
                global $globalCoverArtProviders;
                $coverArtProviders = $globalCoverArtProviders;
        }

        foreach ($coverArtProviders as $provider)
        {
                $coverArtList = $provider->getCoverArtList($artist, $album, $listLimit);
                $results = array_merge($results, $coverArtList->results);

                if ($limit > 0)
                {
                        $listLimit = max(0, $listLimit - count($coverArtList->results));
                        if ($listLimit == 0)
                                break;
                }
        }

        return $results;
}

?>