<?php
    declare(strict_types = 1);
    
    require 'secrets.php';
    require 'mpfuncs.php';
    
    const BASE_URL = 'https://api.spotify.com/v1/';
    const AUTH_URL = 'https://accounts.spotify.com/';
    const DATE_FILE = 'prev_date.txt';
    const DATE_FORM = 'm/d/Y';
    const MONTHS = [
        '01' => 'January',
        '02' => 'February',
        '03' => 'March',
        '04' => 'April',
        '05' => 'May',
        '06' => 'June',
        '07' => 'July',
        '08' => 'August',
        '09' => 'September',
        '10' => 'October',
        '11' => 'November',
        '12' => 'December',
    ];
        
    $code = $_GET['code'];
    
    if (!$code) {
        exit(1);
    }
    
    $today = new DateTime;
    
    #print_r($today);
    
    $prevDTTxt = file_get_contents(DATE_FILE);
    
    $prevDT = $prevDTTxt ? DateTime::createFromFormat(DATE_FORM, $prevDTTxt) : DateTime::createFromFormat(DATE_FORM, $today->format('m/') . '01' . $today->format('/Y'));
    
    if (strcmp($prevDT->format('m'), $today->format('m')) < 0) {
        $prevDT = DateTime::createFromFormat(DATE_FORM, $today->format('m/') . '01' . $today->format('/Y'));
    }
    
    
    #Handle Spotify Token Authorization
    
    $token_data = [
        'grant_type' => 'authorization_code',
        'code' => $code,
        'redirect_uri' => REDIRECT_URI
    ];
    $token_data = http_build_query($token_data);
    
    $token_opts = [
        'http' => [
            'method' => 'POST',
            /*'header' => "Content-type: application/x-www-form-urlencoded\r\n"
                     . "Content-Length: " . strlen($token_data) . "\r\n"
                     . "Authorization: Basic " . base64_encode('868e2cba00de4819900dd8a647a7ba7d:' . CLIENT_SECRET) . "\r\n",*/
            'header' => "Authorization: Basic " . base64_encode('868e2cba00de4819900dd8a647a7ba7d:' . CLIENT_SECRET) . " \r\n",
            'content' => $token_data
        ]
    ];
        
    $token_context = stream_context_create($token_opts);
    
    $spot_req = file_get_contents(AUTH_URL . 'api/token', false, $token_context);
    
    #echo $spot_req;
    $spot_json = json_decode($spot_req, true);

    $spot_token = $spot_json['access_token'];
    
    $me_opts = [
        'http' => [
            'method' => 'GET',
            'header' => 'Authorization: Bearer ' . $spot_token . "\r\n"
        ]
    ];
    
    $me_context = stream_context_create($me_opts);
    
    $me_resp = file_get_contents(BASE_URL . 'me', false, $me_context);
    $me_json = json_decode($me_resp, true);
    $me_id = $me_json['id'];
    
    echo '<br />';
    #print_r($me_resp);
    
    $page = 1;
    $html = file_get_contents('https://www.marketplace.org/latest-music');
    $DOM = new DOMDocument;
    $DOM->loadHTML($html);
    $headers = $DOM->getElementsByTagName('h2');
    $divs = $DOM->getElementsByTagName('div');
    
    $recentEpDT;
    $episodePages = [];
    
    foreach ($headers as $header) {
        if ($header->hasAttribute('class') && $header->getAttribute('class') === 'river--hed') {
            $recentEpDT = DateTime::createFromFormat(DATE_FORM, explode(':', $header->nodeValue)[0]);
            break;
        }
    }
    
    $prevDate = (int) $prevDT->format('d');
    $recentEpDate = (int) $recentEpDT->format('d');
    $daysToGet = ($prevDate === 1) ? $recentEpDate : $recentEpDate - $prevDate;
    $daysToGet = $daysToGet - 2 * (int) ($daysToGet / 7);
    
    if ($daysToGet === 0) {
        echo 'No new episodes since last check.';
        exit(0);
    }

    
    do {
        $episodePages[] = parseEpisodePage($divs, $daysToGet);
    } while ($daysToGet > 0 && ($DOM->loadHTML(file_get_contents('https://www.marketplace.org/latest-music?page=' . ++$page))) && ($divs = $DOM->getElementsByTagName('div')) );

    /*
    echo '<br />';

    print_r($date_headers);
    
    echo '<br />';
    print_r($episodes);
    */
    
    print_r($episodePages);
    
    # Check if this month's playlist exists
    
    $playlistName = MONTHS[$today->format('m')] . ' Marketplace Tracks';
    
    $checkPlaylistOpts = [
        'http' => [
            'method' => 'GET',
            'header' => 'Authorization: Bearer ' . $spot_token . "\r\n"
        ]
    ];
    
    $checkPlaylistContext = stream_context_create($checkPlaylistOpts);
    
    $checkPlaylistReq = file_get_contents(BASE_URL  . 'me/playlists', false, $checkPlaylistContext);
    
    $checkPlaylistJson = json_decode($checkPlaylistReq, true);
            
    foreach ($checkPlaylistJson['items'] as $playlist) {
        #TODO should check if $user owns playlist
        if (!strcmp($playlistName, $playlist['name'])) {
            $playlistID = $playlist['id'];
        }
    }
    
    #echo 'playlistID' . $playlistID;
    
    # Create new playlist if one does not exist
    # DEVELOPMENT TEMP ALWAYS CREATE NEW PLAYLIST
    #if (!$playlistID) {
    if (true) {

        $playlist_data = [
            'name' => $playlistName,
        ];
        
        $playlist_opts = [
            'http' => [
                'method' => 'POST',
                'header' => 'Authorization: Bearer ' . $spot_token . "\r\n"
                        . 'Content-Type application/json \r\n',
                'content' => json_encode($playlist_data)
            ]
        ];

        $playlist_context = stream_context_create($playlist_opts);
        $playlist_req = file_get_contents(BASE_URL . 'users/' . $me_id . '/playlists', false, $playlist_context);
        $playlist_json = json_decode($playlist_req, true);
        $playlistID = $playlist_json['id'];
        
        #echo '<br />' . $playlistID;
        
    }
    
    $uris = [];
    
    foreach ( array_reverse($episodePages) as $episodes) {
        foreach ( array_reverse($episodes) as $episode) {

        $track_opts = [
            'http' => [
                'method' => 'GET',
                'header' => 'Authorization: Bearer ' . $spot_token . "\r\n"
            ]
        ];
    
        $track_context = stream_context_create($track_opts);
    
            foreach ($episode as $song_info) {
    
                $track_search_url = BASE_URL . 'search?q=track:' . urlencode($song_info['title']) 
                                    . '+artist:' . urlencode($song_info['artist']) . '&type=track';
             
                #echo '<br />' . $track_search_url;
                #echo '<br />';
            
                $trackReq = file_get_contents($track_search_url, false, $track_context);
                if ($trackReq) {
                    $trackJSON = json_decode($trackReq, true);
                    $trackJSON = $trackJSON['tracks'];
            
                    print_r($trackJSON);
                    
                    if ($trackJSON['total'] === 0) {
                        continue;
                    }
            
                    $uris[] = $trackJSON['items'][0]['uri'];
            
                    #rate limit
                    sleep(1);

                }
            }
        }
    }
        
    $update_data = [
        'uris' => $uris,
    ];
    
    echo '<br /> update_data <br />';
    #print_r($update_data);
    
    $update_opts = [
        'http' => [
            'method' => 'POST',
            'header' => 'Authorization: Bearer ' . $spot_token . "\r\n"
                     . 'Content-Type application/json \r\n',
            'content' => json_encode($update_data)
        ]
    ];
    
    $update_context = stream_context_create($update_opts);
    $update_url = BASE_URL . 'users/' . $me_id . '/playlists/' . $playlistID . '/tracks';
    echo '<br />' . $update_url;
    echo '<br />';
    echo '<br />' . count($uris);
    echo '<br />';
    print_r(json_encode($update_data));
    $update_req = file_get_contents(BASE_URL . 'users/' . $me_id . '/playlists/' . $playlistID . '/tracks', false, $update_context);
    print_r($update_req);
    
    file_put_contents(DATE_FILE, $recentEpDT->format(DATE_FORM));