<?php
namespace EEPROM;

use Exception;
use Imagick;
use JsonSerializable;

class UploadNotFoundException extends Exception {};
class UploadCreationFailedException extends Exception {};

final class Upload implements JsonSerializable {
    private const ID_CHARS = 'AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz0123456789-_';

    public function getId(): string {
        return $this->upload_id;
    }

    public function getPath(): string {
        return PRM_UPLOADS . '/' . $this->getId();
    }
    public function getThumbPath(): string {
        return PRM_THUMBS . '/' . $this->getId();
    }
    public function getRemotePath(): string {
        return '/uploads/' . $this->getId();
    }
    public function getPublicUrl(bool $forceReal = false): string {
        if(!$forceReal && Config::has('Uploads', 'short_domain'))
            return '//' . Config::get('Uploads', 'short_domain') . '/' . $this->getId();
        return '//' . $_SERVER['HTTP_HOST'] . $this->getRemotePath();
    }
    public function getPublicThumbUrl(bool $forceReal = false): string {
        return $this->getPublicUrl($forceReal) . '.t';
    }

    public function getUserId(): int {
        return $this->user_id ?? 0;
    }
    public function setUserId(int $userId): void {
        $this->user_id = $userId;
    }
    public function getUser(): User {
        return User::byId($this->getUserId());
    }
    public function setUser(User $user): void {
        $this->setUserId($user->getId());
    }

    public function getApplicationId(): int {
        return $this->app_id ?? 0;
    }
    public function setApplicationId(int $appId): void {
        $this->app_id = $appId;

        $updateAppl = DB::prepare('
            UPDATE `prm_uploads`
            SET `app_id` = :app
            WHERE `upload_id` = :upload
        ');
        $updateAppl->bindValue('app', $appId);
        $updateAppl->bindValue('upload', $this->getId());
        $updateAppl->execute();
    }
    public function getApplication(): User {
        return Application::byId($this->getApplicationId());
    }
    public function setApplication(Application $app): void {
        $this->setApplicationId($app->getId());
    }

    public function getType(): string {
        return $this->upload_type ?? 'text/plain';
    }
    public function isImage(): bool {
        return substr($this->getType(), 0, 6) === 'image/';
    }
    public function isVideo(): bool {
        return substr($this->getType(), 0, 6) === 'video/';
    }
    public function isAudio(): bool {
        return substr($this->getType(), 0, 6) === 'audio/';
    }

    public function getName(): string {
        return $this->upload_name ?? '';
    }

    public function getSize(): int {
        return $this->upload_size ?? 0;
    }

    public function getHash(): string {
        return $this->upload_hash ?? str_pad('', 64, '0');
    }

    public function getCreated(): int {
        return $this->upload_created;
    }

    public function getLastAccessed(): int {
        return $this->upload_accessed ?? 0;
    }
    public function bumpAccess(): void {
        if(empty($this->getId()))
            return;
        $this->upload_accessed = time();
        $bumpAccess = DB::prepare('
            UPDATE `prm_uploads`
            SET `upload_accessed` = NOW()
            WHERE `upload_id` = :upload
        ');
        $bumpAccess->bindValue('upload', $this->getId());
        $bumpAccess->execute();
    }

    public function getExpires(): int {
        return $this->upload_expires ?? 0;
    }
    public function hasExpired(): bool {
        return $this->getExpires() > 1 && $this->getExpires() <= time();
    }

    public function getDeleted(): int {
        return $this->upload_deleted ?? 0;
    }
    public function isDeleted(): bool {
        return $this->getDeleted() > 0;
    }

    public function getDMCA(): int {
        return $this->upload_dmca ?? 0;
    }
    public function isDMCA(): bool {
        return $this->getDMCA() > 0;
    }

    public function getExpiryBump(): int {
        return $this->upload_bump ?? 0;
    }

    public function bumpExpiry(): void {
        if(empty($this->getId()) || $this->getExpires() < 1)
            return;
        $bumpSeconds = $this->getExpiryBump();

        if($bumpSeconds < 1)
            return;
        $this->upload_expires = time() + $bumpSeconds;

        $bumpExpiry = DB::prepare('
            UPDATE `prm_uploads`
            SET `upload_expires` = NOW() + INTERVAL :seconds SECOND
            WHERE `upload_id` = :upload
        ');
        $bumpExpiry->bindValue('seconds', $bumpSeconds);
        $bumpExpiry->bindValue('upload', $this->getId());
        $bumpExpiry->execute();
    }

    public function restore(): void {
        $this->upload_deleted = null;
        $restore = DB::prepare('
            UPDATE `prm_uploads`
            SET `upload_deleted` = NULL
            WHERE `upload_id` = :id
        ');
        $restore->bindValue('id', $this->getId());
        $restore->execute();
    }

    public function delete(bool $hard): void {
        $this->upload_deleted = time();

        if($hard) {
            if(is_file($this->getPath()))
                unlink($this->getPath());
            if(is_file($this->getThumbPath()))
                unlink($this->getThumbPath());

            if($this->getDMCA() < 1) {
                $delete = DB::prepare('
                    DELETE FROM `prm_uploads`
                    WHERE `upload_id` = :id
                ');
                $delete->bindValue('id', $this->getId());
                $delete->execute();
            }
        } else {
            $delete = DB::prepare('
                UPDATE `prm_uploads`
                SET `upload_deleted` = NOW()
                WHERE `upload_id` = :id
            ');
            $delete->bindValue('id', $this->getId());
            $delete->execute();
        }
    }

    public function jsonSerialize() {
        return [
            'id' => $this->getId(),
            'url' => $this->getPublicUrl(),
            'urlf' => $this->getPublicUrl(true),
            'thumb' => $this->getPublicThumbUrl(),
            'name' => $this->getName(),
            'type' => $this->getType(),
            'size' => $this->getSize(),
            'user' => $this->getUserId(),
            'appl' => $this->getApplicationId(),
            'hash' => $this->getHash(),
            'created' => date('c', $this->getCreated()),
            'accessed' => $this->getLastAccessed() < 1 ? null : date('c', $this->getLastAccessed()),
            'expires' => $this->getExpires() < 1 ? null : date('c', $this->getExpires()),
            'deleted' => $this->getDeleted() < 1 ? null : date('c', $this->getDeleted()),
            'dmca' => $this->getDMCA() < 1 ? null : date('c', $this->getDMCA()),
        ];
    }

    public static function generateId(int $length = 32): string {
        $token = random_bytes($length);
        $chars = strlen(self::ID_CHARS);

        for($i = 0; $i < $length; $i++)
            $token[$i] = self::ID_CHARS[ord($token[$i]) % $chars];

        return $token;
    }

    public static function create(
        Application $app, User $user,
        string $fileName, string $fileType,
        string $fileSize, string $fileHash,
        int $fileExpiry, bool $bumpExpiry
    ): self {
        $appId = $app->getId();
        $userId = $user->getId();

        if(strpos($fileType, '/') === false || $fileSize < 1 || strlen($fileHash) !== 64 || $fileExpiry < 0)
            throw new UploadCreationFailedException('Bad args.');

        $id = self::generateId();
        $create = DB::prepare('
            INSERT INTO `prm_uploads` (
                `upload_id`, `app_id`, `user_id`, `upload_name`,
                `upload_type`, `upload_size`, `upload_hash`, `upload_ip`,
                `upload_expires`, `upload_bump`
            ) VALUES (
                :id, :app, :user, :name, :type, :size,
                UNHEX(:hash), INET6_ATON(:ip),
                FROM_UNIXTIME(:expire), :bump
            )
        ');
        $create->bindValue('id', $id);
        $create->bindValue('app', $appId < 1 ? null : $appId);
        $create->bindValue('user', $userId < 1 ? null : $userId);
        $create->bindValue('ip', $_SERVER['REMOTE_ADDR']);
        $create->bindValue('name', $fileName);
        $create->bindValue('type', $fileType);
        $create->bindValue('hash', $fileHash);
        $create->bindValue('size', $fileSize);
        $create->bindValue('expire', $fileExpiry > 0 ? (time() + $fileExpiry) : 0);
        $create->bindValue('bump', $bumpExpiry ? $fileExpiry : 0);
        $create->execute();

        try {
            return self::byId($id);
        } catch(UploadNotFoundException $ex) {
            throw new UploadCreationFailedException;
        }
    }

    public static function byId(string $id): self {
        $getUpload = DB::prepare('
            SELECT `upload_id`, `app_id`, `user_id`, `upload_name`, `upload_type`, `upload_size`, `upload_bump`,
                UNIX_TIMESTAMP(`upload_created`) AS `upload_created`,
                UNIX_TIMESTAMP(`upload_accessed`) AS `upload_accessed`,
                UNIX_TIMESTAMP(`upload_expires`) AS `upload_expires`,
                UNIX_TIMESTAMP(`upload_deleted`) AS `upload_deleted`,
                UNIX_TIMESTAMP(`upload_dmca`) AS `upload_dmca`,
                INET6_NTOA(`upload_ip`) AS `upload_ip`,
                LOWER(HEX(`upload_hash`)) AS `upload_hash`
            FROM `prm_uploads`
            WHERE `upload_id` = :id
            AND `upload_deleted` IS NULL
        ');
        $getUpload->bindValue('id', $id);
        $upload = $getUpload->execute() ? $getUpload->fetchObject(self::class) : false;

        if(!$upload)
            throw new UploadNotFoundException;

        return $upload;
    }

    public static function byHash(string $hash): ?self {
        $getUpload = DB::prepare('
            SELECT `upload_id`, `app_id`, `user_id`, `upload_name`, `upload_type`, `upload_size`, `upload_bump`,
                UNIX_TIMESTAMP(`upload_created`) AS `upload_created`,
                UNIX_TIMESTAMP(`upload_accessed`) AS `upload_accessed`,
                UNIX_TIMESTAMP(`upload_expires`) AS `upload_expires`,
                UNIX_TIMESTAMP(`upload_deleted`) AS `upload_deleted`,
                UNIX_TIMESTAMP(`upload_dmca`) AS `upload_dmca`,
                INET6_NTOA(`upload_ip`) AS `upload_ip`,
                LOWER(HEX(`upload_hash`)) AS `upload_hash`
            FROM `prm_uploads`
            WHERE `upload_hash` = UNHEX(:hash)
        ');
        $getUpload->bindValue('hash', $hash);
        $upload = $getUpload->execute() ? $getUpload->fetchObject(self::class) : false;
        return $upload ? $upload : null;
    }

    public static function deleted(): array {
        $getDeleted = DB::prepare('
            SELECT `upload_id`, `app_id`, `user_id`, `upload_name`, `upload_type`, `upload_size`, `upload_bump`,
                UNIX_TIMESTAMP(`upload_created`) AS `upload_created`,
                UNIX_TIMESTAMP(`upload_accessed`) AS `upload_accessed`,
                UNIX_TIMESTAMP(`upload_expires`) AS `upload_expires`,
                UNIX_TIMESTAMP(`upload_deleted`) AS `upload_deleted`,
                UNIX_TIMESTAMP(`upload_dmca`) AS `upload_dmca`,
                INET6_NTOA(`upload_ip`) AS `upload_ip`,
                LOWER(HEX(`upload_hash`)) AS `upload_hash`
            FROM `prm_uploads`
            WHERE `upload_deleted` IS NOT NULL
            OR `upload_dmca` IS NOT NULL
            OR `user_id` IS NULL
            OR `app_id` IS NULL
        ');
        if(!$getDeleted->execute())
            return [];

        $deleted = [];

        while($upload = $getDeleted->fetchObject(self::class))
            $deleted[] = $upload;

        return $deleted;
    }

    public static function expired(): array {
        $getExpired = DB::prepare('
            SELECT `upload_id`, `app_id`, `user_id`, `upload_name`, `upload_type`, `upload_size`, `upload_bump`,
                UNIX_TIMESTAMP(`upload_created`) AS `upload_created`,
                UNIX_TIMESTAMP(`upload_accessed`) AS `upload_accessed`,
                UNIX_TIMESTAMP(`upload_expires`) AS `upload_expires`,
                UNIX_TIMESTAMP(`upload_deleted`) AS `upload_deleted`,
                UNIX_TIMESTAMP(`upload_dmca`) AS `upload_dmca`,
                INET6_NTOA(`upload_ip`) AS `upload_ip`,
                LOWER(HEX(`upload_hash`)) AS `upload_hash`
            FROM `prm_uploads`
            WHERE `upload_expires` IS NOT NULL
            AND `upload_expires` <= NOW()
            AND `upload_dmca` IS NULL
        ');
        if(!$getExpired->execute())
            return [];

        $deleted = [];

        while($upload = $getExpired->fetchObject(self::class))
            $deleted[] = $upload;

        return $deleted;
    }

    public static function all(int $limit = 0, string $after = ''): array {
        $query = '
            SELECT `upload_id`, `app_id`, `user_id`, `upload_name`, `upload_type`, `upload_size`, `upload_bump`,
                UNIX_TIMESTAMP(`upload_created`) AS `upload_created`,
                UNIX_TIMESTAMP(`upload_accessed`) AS `upload_accessed`,
                UNIX_TIMESTAMP(`upload_expires`) AS `upload_expires`,
                UNIX_TIMESTAMP(`upload_deleted`) AS `upload_deleted`,
                UNIX_TIMESTAMP(`upload_dmca`) AS `upload_dmca`,
                INET6_NTOA(`upload_ip`) AS `upload_ip`,
                LOWER(HEX(`upload_hash`)) AS `upload_hash`
            FROM `prm_uploads`
        ';

        if(!empty($after))
            $query .= ' WHERE `upload_id` > :after';

        $query .= ' ORDER BY `upload_id`';

        if($limit > 0)
            $query .= sprintf(' LIMIT %d', $limit);

        $getUploads = DB::prepare($query);

        if(!empty($after))
            $getUploads->bindValue('after', $after);

        $getUploads->execute();
        $out = [];

        while($upload = $getUploads->fetchObject(self::class))
            $out[] = $upload;

        return $out;
    }

    public function supportsThumbnail(): bool {
        return $this->isImage() || $this->isAudio() || $this->isVideo();
    }

    public function createThumbnail(): void {
        $tmpFile = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'eeprom' . bin2hex(random_bytes(10)) . '.jpg';

        try {
            if($this->isImage())
                $imagick = new Imagick($this->getPath());
            elseif($this->isAudio())
                $imagick = $this->getCoverFromAudio($tmpFile);
            elseif($this->isVideo())
                $imagick = $this->getFrameFromVideo($tmpFile);

            if(!isset($imagick))
                return;

            $imagick->setImageFormat('jpg');
            $imagick->setImageCompressionQuality(40);

            $thumbRes = 100;
            $width = $imagick->getImageWidth();
            $height = $imagick->getImageHeight();

            if ($width > $height) {
                $resizeWidth = $width * $thumbRes / $height;
                $resizeHeight = $thumbRes;
            } else {
                $resizeWidth = $thumbRes;
                $resizeHeight = $height * $thumbRes / $width;
            }

            $imagick->resizeImage(
                $resizeWidth, $resizeHeight,
                Imagick::FILTER_GAUSSIAN, 0.7
            );

            $imagick->cropImage(
                $thumbRes,
                $thumbRes,
                ($resizeWidth - $thumbRes) / 2,
                ($resizeHeight - $thumbRes) / 2
            );

            $imagick->writeImage($this->getThumbPath());
        } catch(Exception $ex) {}

        if(is_file($tmpFile))
            unlink($tmpFile);
    }

    private function getFrameFromVideo(string $path): Imagick {
        shell_exec(sprintf('ffmpeg -i %s -ss 00:00:01.000 -vframes 1 %s', $this->getPath(), $path));
        return new Imagick($path);
    }

    private function getCoverFromAudio(string $path): Imagick {
        shell_exec(sprintf('ffmpeg -i %s -an -vcodec copy %s', $this->getPath(), $path));
        return new Imagick($path);
    }
}