<?php declare(strict_types=1);
namespace openvk\Web\Models\Entities;
use Chandler\Database\DatabaseConnection;
use openvk\Web\Util\Shell\Exceptions\UnknownCommandException;
use openvk\Web\Util\Shell\Shell;

/**
 * @method setName(string)
 * @method setPerformer(string)
 * @method setLyrics(string)
 * @method setExplicit(bool)
 */
class Audio extends Media
{
    protected $tableName     = "audios";
    protected $fileExtension = "mpd";

    # Taken from winamp :D
    const genres = [
        'A Cappella', 'Abstract', 'Acid', 'Acid Jazz', 'Acid Punk', 'Acoustic', 'AlternRock', 'Alternative', 'Ambient', 'Anime', 'Art Rock', 'Audio Theatre', 'Audiobook', 'Avantgarde', 'Ballad', 'Baroque', 'Bass', 'Beat', 'Bebob', 'Bhangra', 'Big Band', 'Big Beat', 'Black Metal', 'Bluegrass', 'Blues', 'Booty Bass', 'Breakbeat', 'BritPop', 'Cabaret', 'Celtic', 'Chamber Music', 'Chanson', 'Chillout', 'Chorus', 'Christian Gangsta Rap', 'Christian Rap', 'Christian Rock', 'Classic Rock', 'Classical', 'Club', 'Club-House', 'Comedy', 'Contemporary Christian', 'Country', 'Crossover', 'Cult', 'Dance', 'Dance Hall', 'Darkwave', 'Death Metal', 'Disco', 'Downtempo', 'Dream', 'Drum & Bass', 'Drum Solo', 'Dub', 'Dubstep', 'Duet', 'EBM', 'Easy Listening', 'Eclectic', 'Electro', 'Electroclash', 'Electronic', 'Emo', 'Ethnic', 'Euro-House', 'Euro-Techno', 'Eurodance', 'Experimental', 'Fast Fusion', 'Folk', 'Folk-Rock', 'Folklore', 'Freestyle', 'Funk', 'Fusion', 'G-Funk', 'Game', 'Gangsta Rap', 'Garage', 'Garage Rock', 'Global', 'Goa', 'Gospel', 'Gothic', 'Gothic Rock', 'Grunge', 'Hard Rock', 'Hardcore', 'Heavy Metal', 'Hip-Hop', 'House', 'Humour', 'IDM', 'Illbient', 'Indie', 'Indie Rock', 'Industrial', 'Industro-Goth', 'Instrumental', 'Instrumental Pop', 'Instrumental Rock', 'JPop', 'Jam Band', 'Jazz', 'Jazz+Funk', 'Jungle', 'Krautrock', 'Latin', 'Leftfield', 'Lo-Fi', 'Lounge', 'Math Rock', 'Meditative', 'Merengue', 'Metal', 'Musical', 'National Folk', 'Native American', 'Negerpunk', 'Neoclassical', 'Neue Deutsche Welle', 'New Age', 'New Romantic', 'New Wave', 'Noise', 'Nu-Breakz', 'Oldies', 'Opera', 'Other', 'Podcast', 'Polka', 'Polsk Punk', 'Pop', 'Pop / Funk', 'Pop-Folk', 'Porn Groove', 'Post-Punk', 'Post-Rock', 'Power Ballad', 'Pranks', 'Primus', 'Progressive Rock', 'Psybient', 'Psychedelic', 'Psychedelic Rock', 'Psychobilly', 'Psytrance', 'Punk', 'Punk Rock', 'R&B', 'Rap', 'Rave', 'Reggae', 'Retro', 'Revival', 'Rhythmic Soul', 'Rock', 'Rock & Roll', 'Salsa', 'Samba', 'Satire', 'Shoegaze', 'Showtunes', 'Ska', 'Slow Jam', 'Slow Rock', 'Sonata', 'Soul', 'Sound Clip', 'Soundtrack', 'Southern Rock', 'Space', 'Space Rock', 'Speech', 'Swing', 'Symphonic Rock', 'Symphony', 'Synthpop', 'Tango', 'Techno', 'Techno-Industrial', 'Terror', 'Thrash Metal', 'Top 40', 'Touhou', 'Trailer', 'Trance', 'Tribal', 'Trip-Hop', 'Trop Rock', 'Vocal', 'World Music'
    ];

    # Taken from: https://web.archive.org/web/20220322153107/https://dev.vk.com/reference/objects/audio-genres
    const vkGenres = [
        "Rock"               => 1,
        "Pop"                => 2,
        "Rap"                => 3,
        "Hip-Hop"            => 3, # VK API lists №3 as Rap & Hip-Hop, but these genres are distinct in OpenVK
        "Easy Listening"     => 4,
        "House"              => 5,
        "Dance"              => 5,
        "Instrumental"       => 6,
        "Metal"              => 7,
        "Alternative"        => 21,
        "Dubstep"            => 8,
        "Jazz"               => 1001,
        "Blues"              => 1001,
        "Drum & Bass"        => 10,
        "Trance"             => 11,
        "Chanson"            => 12,
        "Ethnic"             => 13,
        "Acoustic"           => 14,
        "Vocal"              => 14,
        "Reggae"             => 15,
        "Classical"          => 16,
        "Indie Pop"          => 17,
        "Speech"             => 19,
        "Disco"              => 22,
        "Other"              => 18,
    ];

    private function fileLength(string $filename): int
    {
        if(!Shell::commandAvailable("ffmpeg") || !Shell::commandAvailable("ffprobe"))
            throw new \Exception();

        $error   = NULL;
        $streams = Shell::ffprobe("-i", $filename, "-show_streams", "-select_streams a", "-loglevel error")->execute($error);
        if($error !== 0)
            throw new \DomainException("$filename is not recognized as media container");
        else if(empty($streams) || ctype_space($streams))
            throw new \DomainException("$filename does not contain any audio streams");

        $vstreams = Shell::ffprobe("-i", $filename, "-show_streams", "-select_streams v", "-loglevel error")->execute($error);
        
        # check if audio has cover (attached_pic)
        preg_match("%attached_pic=([0-1])%", $vstreams, $hasCover);
        if(!empty($vstreams) && !ctype_space($vstreams) && ((int)($hasCover[1]) !== 1))
            throw new \DomainException("$filename is a video");

        $durations = [];
        preg_match_all('%duration=([0-9\.]++)%', $streams, $durations);
        if(sizeof($durations[1]) === 0)
            throw new \DomainException("$filename does not contain any meaningful audio streams");

        $length = 0;
        foreach($durations[1] as $duration) {
            $duration = floatval($duration);
            if($duration < 1.0 || $duration > 65536.0)
                throw new \DomainException("$filename does not contain any meaningful audio streams");
            else
                $length = max($length, $duration);
        }

        return (int) round($length, 0, PHP_ROUND_HALF_EVEN);
    }

    /**
     * @throws \Exception
     */
    protected function saveFile(string $filename, string $hash): bool
    {
        $duration = $this->fileLength($filename);

        $kid = openssl_random_pseudo_bytes(16);
        $key = openssl_random_pseudo_bytes(16);
        $tok = openssl_random_pseudo_bytes(28);
        $ss  = ceil($duration / 15);

        $this->stateChanges("kid", $kid);
        $this->stateChanges("key", $key);
        $this->stateChanges("token", $tok);
        $this->stateChanges("segment_size", $ss);
        $this->stateChanges("length", $duration);

        try {
            $args = [
                str_replace("enabled", "available", OPENVK_ROOT),
                str_replace("enabled", "available", $this->getBaseDir()),
                $hash,
                $filename,

                bin2hex($kid),
                bin2hex($key),
                bin2hex($tok),
                $ss,
            ];

            if(Shell::isPowershell()) {
                Shell::powershell("-executionpolicy bypass", "-File", __DIR__ . "/../shell/processAudio.ps1", ...$args)
                ->start();
            } else {
                Shell::bash(__DIR__ . "/../shell/processAudio.sh", ...$args) // Pls workkkkk
                ->start();                                                    // idk, not tested :")
            }

            # Wait until processAudio will consume the file
            $start = time();
            while(file_exists($filename))
                if(time() - $start > 5)
                    throw new \RuntimeException("Timed out waiting FFMPEG");

         } catch(UnknownCommandException $ucex) {
             exit(OPENVK_ROOT_CONF["openvk"]["debug"] ? "bash/pwsh is not installed" : VIDEOS_FRIENDLY_ERROR);
         }

        return true;
    }

    function getTitle(): string
    {
        return $this->getRecord()->name;
    }

    function getPerformer(): string
    {
        return $this->getRecord()->performer;
    }

    function getName(): string
    {
        return $this->getPerformer() . " — " . $this->getTitle();
    }

    function getGenre(): ?string
    {
        return $this->getRecord()->genre;
    }

    function getLyrics(): ?string
    {
        return !is_null($this->getRecord()->lyrics) ? htmlspecialchars($this->getRecord()->lyrics, ENT_DISALLOWED | ENT_XHTML) : NULL;
    }

    function getLength(): int
    {
        return $this->getRecord()->length;
    }

    function getFormattedLength(): string
    {
        $len  = $this->getLength();
        $mins = floor($len / 60);
        $secs = $len - ($mins * 60);

        return (
            str_pad((string) $mins, 2, "0", STR_PAD_LEFT)
            . ":" .
            str_pad((string) $secs, 2, "0", STR_PAD_LEFT)
        );
    }

    function getSegmentSize(): float
    {
        return $this->getRecord()->segment_size;
    }

    function getListens(): int
    {
        return $this->getRecord()->listens;
    }

    function getOriginalURL(bool $force = false): string
    {
        $disallowed = !OPENVK_ROOT_CONF["openvk"]["preferences"]["music"]["exposeOriginalURLs"] && !$force;
        if(!$this->isAvailable() || $disallowed)
            return ovk_scheme(true)
                . $_SERVER["HTTP_HOST"] . ":"
                . $_SERVER["HTTP_PORT"]
                . "/assets/packages/static/openvk/audio/nomusic.mp3";

        $key = bin2hex($this->getRecord()->token);

        return str_replace(".mpd", "_fragments", $this->getURL()) . "/original_$key.mp3";
    }

    function getURL(?bool $force = false): string
    {
        if ($this->isWithdrawn()) return "";

        return parent::getURL();
    }

    function getKeys(): array
    {
        $keys[bin2hex($this->getRecord()->kid)] = bin2hex($this->getRecord()->key);

        return $keys;
    }

    function isAnonymous(): bool
    {
        return false;
    }

    function isExplicit(): bool
    {
        return (bool) $this->getRecord()->explicit;
    }

    function isWithdrawn(): bool
    {
        return (bool) $this->getRecord()->withdrawn;
    }

    function isUnlisted(): bool
    {
        return (bool) $this->getRecord()->unlisted;
    }

    # NOTICE may flush model to DB if it was just processed
    function isAvailable(): bool
    {
        if($this->getRecord()->processed)
            return true;

        # throttle requests to isAvailable to prevent DoS attack if filesystem is actually an S3 storage
        if(time() - $this->getRecord()->checked < 5)
            return false;

        try {
            $fragments = str_replace(".mpd", "_fragments", $this->getFileName());
            $original = "original_" . bin2hex($this->getRecord()->token) . ".mp3";
            if(file_exists("$fragments/$original")) {
                # Original gets uploaded after fragments
                $this->stateChanges("processed", 0x01);

                return true;
            }
        } finally {
            $this->stateChanges("checked", time());
            $this->save();
        }

        return false;
    }

    function isInLibraryOf($entity): bool
    {
        return sizeof(DatabaseConnection::i()->getContext()->table("audio_relations")->where([
            "entity" => $entity->getId() * ($entity instanceof Club ? -1 : 1),
            "audio"  => $this->getId(),
        ])) != 0;
    }

    function add($entity): bool
    {
        if($this->isInLibraryOf($entity))
            return false;

        $entityId  = $entity->getId() * ($entity instanceof Club ? -1 : 1);
        $audioRels = DatabaseConnection::i()->getContext()->table("audio_relations");
        if(sizeof($audioRels->where("entity", $entityId)) > 65536)
            throw new \OverflowException("Can't have more than 65536 audios in a playlist");

        $audioRels->insert([
            "entity" => $entityId,
            "audio"  => $this->getId(),
        ]);

        return true;
    }

    function remove($entity): bool
    {
        if(!$this->isInLibraryOf($entity))
            return false;

        DatabaseConnection::i()->getContext()->table("audio_relations")->where([
            "entity" => $entity->getId() * ($entity instanceof Club ? -1 : 1),
            "audio"  => $this->getId(),
        ])->delete();

        return true;
    }

    function listen($entity, Playlist $playlist = NULL): bool
    {
        $listensTable = DatabaseConnection::i()->getContext()->table("audio_listens");
        $lastListen   = $listensTable->where([
            "entity" => $entity->getRealId(),
            "audio"  => $this->getId(),
        ])->order("index DESC")->fetch();
        
        if(!$lastListen || (time() - $lastListen->time >= $this->getLength())) {
            $listensTable->insert([
                "entity" => $entity->getRealId(),
                "audio"  => $this->getId(),
                "time"   => time(),
                "playlist" => $playlist ? $playlist->getId() : NULL,
            ]);

            if($entity instanceof User) {
                $this->stateChanges("listens", ($this->getListens() + 1));
                $this->save();

                if($playlist) {
                    $playlist->incrementListens();
                    $playlist->save();
                }
            }

            $entity->setLast_played_track($this->getId());
            $entity->save();

            return true;
        }

        $lastListen->update([
            "time" => time(),
        ]);

        return false;
    }

    /**
     * Returns compatible with VK API 4.x, 5.x structure.
     *
     * Always sets album(_id) to NULL at this time.
     * If genre is not present in VK genre list, fallbacks to "Other".
     * The url and manifest properties will be set to false if the audio can't be played (processing, removed).
     *
     * Aside from standard VK properties, this method will also return some OVK extended props:
     * 1. added - Is in the library of $user?
     * 2. editable - Can be edited by $user?
     * 3. withdrawn - Removed due to copyright request?
     * 4. ready - Can be played at this time?
     * 5. genre_str - Full name of genre, NULL if it's undefined
     * 6. manifest - URL to MPEG-DASH manifest
     * 7. keys - ClearKey DRM keys
     * 8. explicit - Marked as NSFW?
     * 9. searchable - Can be found via search?
     * 10. unique_id - Unique ID of audio
     *
     * @notice that in case if exposeOriginalURLs is set to false in config, "url" will always contain link to nomusic.mp3,
     * unless $forceURLExposure is set to true.
     *
     * @notice may trigger db flush if the audio is not processed yet, use with caution on unsaved models.
     *
     * @param ?User $user user, relative to whom "added", "editable" will be set
     * @param bool $forceURLExposure force set "url" regardless of config
     */
    function toVkApiStruct(?User $user = NULL, bool $forceURLExposure = false): object
    {
        $obj = (object) [];
        $obj->unique_id  = base64_encode((string) $this->getId());
        $obj->id         = $obj->aid = $this->getVirtualId();
        $obj->artist     = $this->getPerformer();
        $obj->title      = $this->getTitle();
        $obj->duration   = $this->getLength();
        $obj->album_id   = $obj->album = NULL; # i forgor to implement
        $obj->url        = false;
        $obj->manifest   = false;
        $obj->keys       = false;
        $obj->genre_id   = $obj->genre = self::vkGenres[$this->getGenre() ?? ""] ?? 18; # return Other if no match
        $obj->genre_str  = $this->getGenre();
        $obj->owner_id   = $this->getOwner()->getId();
        if($this->getOwner() instanceof Club)
            $obj->owner_id *= -1;

        $obj->lyrics = NULL;
        if(!is_null($this->getLyrics()))
            $obj->lyrics = $this->getId();

        $obj->added      = $user && $this->isInLibraryOf($user);
        $obj->editable   = $user && $this->canBeModifiedBy($user);
        $obj->searchable = !$this->isUnlisted();
        $obj->explicit   = $this->isExplicit();
        $obj->withdrawn  = $this->isWithdrawn();
        $obj->ready      = $this->isAvailable() && !$obj->withdrawn;
        if($obj->ready) {
            $obj->url      = $this->getOriginalURL($forceURLExposure);
            $obj->manifest = $this->getURL();
            $obj->keys     = $this->getKeys();
        }

        return $obj;
    }

    function setOwner(int $oid): void
    {
        # WARNING: API implementation won't be able to handle groups like that, don't remove
        if($oid <= 0)
            throw new \OutOfRangeException("Only users can be owners of audio!");

        $this->stateChanges("owner", $oid);
    }

    function setGenre(string $genre): void
    {
        if(!in_array($genre, Audio::genres)) {
            $this->stateChanges("genre", NULL);
            return;
        }

        $this->stateChanges("genre", $genre);
    }

    function setCopyrightStatus(bool $withdrawn = true): void {
        $this->stateChanges("withdrawn", $withdrawn);
    }

    function setSearchability(bool $searchable = true): void {
        $this->stateChanges("unlisted", !$searchable);
    }

    function setToken(string $tok): void {
        throw new \LogicException("Changing keys is not supported.");
    }

    function setKid(string $kid): void {
        throw new \LogicException("Changing keys is not supported.");
    }

    function setKey(string $key): void {
        throw new \LogicException("Changing keys is not supported.");
    }

    function setLength(int $len): void {
        throw new \LogicException("Changing length is not supported.");
    }

    function setSegment_Size(int $len): void {
        throw new \LogicException("Changing length is not supported.");
    }

    function delete(bool $softly = true): void
    {
        $ctx = DatabaseConnection::i()->getContext();
        $ctx->table("audio_relations")->where("audio", $this->getId())
            ->delete();
        $ctx->table("audio_listens")->where("audio", $this->getId())
            ->delete();
        $ctx->table("playlist_relations")->where("media", $this->getId())
            ->delete();

        parent::delete($softly);
    }
}