<?php
/**
 * Simple MediaService
 * - fetchFromGraph(mediaId) -> gets Graph API URL and downloads
 * - storeContent($bytes, $destPath)
 * - createThumbnail($srcPath, $thumbPath)
 */
class MediaService {
    private $token;
    private $apiUrl;
    private $uploadsDir;

    public function __construct() {
        $this->token = getConfigFromDB('whatsapp_token', '');
        $this->apiUrl = rtrim(getConfigFromDB('whatsapp_api_url', 'https://graph.facebook.com/v22.0/'), '/');
        $this->uploadsDir = __DIR__ . '/../uploads/media';
        if (!is_dir($this->uploadsDir)) mkdir($this->uploadsDir, 0755, true);
    }

    public function fetchAndStoreFromGraph($mediaId, $subdir = '') {
        // Obtener metadata (url)
        $endpoint = "{$this->apiUrl}/{$mediaId}";
        $ch = curl_init();
        curl_setopt_array($ch, [
            CURLOPT_URL => $endpoint,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HTTPHEADER => ['Authorization: Bearer ' . $this->token],
            CURLOPT_TIMEOUT => 15
        ]);
        $resp = curl_exec($ch);
        $http = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $err = curl_error($ch);
        curl_close($ch);

        if ($err || $http >= 400) {
            throw new Exception('Graph API fetch failed: ' . $err);
        }
        $decoded = json_decode($resp, true);
        $mediaUrl = $decoded['url'] ?? ($decoded['data'][0]['url'] ?? null);
        if (!$mediaUrl) throw new Exception('No media url from Graph');

        // Descargar contenido (primer intento)
        $content = $this->downloadUrl($mediaUrl);
        if ($content === false) {
            // Reintentar con header Referer (algunos endpoints requieren referer)
            $content = $this->downloadUrl($mediaUrl, ['Referer: https://graph.facebook.com']);
        }
        if ($content === false) throw new Exception('Failed to download media content from ' . $mediaUrl);

        // Detectar extension desde mime o url
        $mime = $decoded['mime_type'] ?? null;
        $ext = $this->extensionFromMime($mime) ?: pathinfo(parse_url($mediaUrl, PHP_URL_PATH), PATHINFO_EXTENSION) ?: 'bin';

        $dir = $this->uploadsDir . ($subdir ? '/' . trim($subdir, '/') : '');
        if (!is_dir($dir)) mkdir($dir, 0755, true);

        $filename = uniqid('m_') . '.' . $ext;
        $fullPath = $dir . '/' . $filename;
        file_put_contents($fullPath, $content);

        $result = ['local_file' => 'uploads/media' . ($subdir ? '/' . trim($subdir, '/') : '') . '/' . $filename, 'mime_type' => $mime, 'size' => filesize($fullPath)];

        // Si es imagen, generar miniatura
        if ($this->isImageMime($mime) || preg_match('#^jpe?g|png|gif$#i', $ext)) {
            $thumbPath = $dir . '/thumb_' . $filename . '.jpg';
            $thumbRel = dirname($result['local_file']) . '/thumb_' . $filename . '.jpg';
            if ($this->createThumbnail($fullPath, $thumbPath)) {
                $result['local_thumb'] = $thumbRel;
            }
        }

        return $result;
    }

    // Nuevo: descargar y almacenar desde una URL directa
    public function fetchAndStoreFromUrl($url, $subdir = '') {
        $content = $this->downloadUrl($url);
        if ($content === false) {
            $content = $this->downloadUrl($url, ['Referer: https://graph.facebook.com']);
        }
        if ($content === false) throw new Exception('Failed to download media content from url ' . $url);

        // intentar inferir mime
        $mime = null;
        $ext = pathinfo(parse_url($url, PHP_URL_PATH), PATHINFO_EXTENSION) ?: 'bin';
        $dir = $this->uploadsDir . ($subdir ? '/' . trim($subdir, '/') : '');
        if (!is_dir($dir)) mkdir($dir, 0755, true);
        $filename = uniqid('m_') . '.' . $ext;
        $fullPath = $dir . '/' . $filename;
        file_put_contents($fullPath, $content);

        $result = ['local_file' => 'uploads/media' . ($subdir ? '/' . trim($subdir, '/') : '') . '/' . $filename, 'mime_type' => $mime, 'size' => filesize($fullPath)];

        // Si parece imagen, intentar crear thumb
        if (preg_match('#jpe?g|png|gif#i', $ext)) {
            $thumbPath = $dir . '/thumb_' . $filename . '.jpg';
            $thumbRel = dirname($result['local_file']) . '/thumb_' . $filename . '.jpg';
            if ($this->createThumbnail($fullPath, $thumbPath)) {
                $result['local_thumb'] = $thumbRel;
            }
        }

        return $result;
    }

    public function downloadUrl($url, $extraHeaders = []) {
        // Incluir Authorization Bearer si está configurado (necesario para algunos endpoints)
        $authHeader = [];
        if (!empty($this->token)) {
            $authHeader[] = 'Authorization: Bearer ' . $this->token;
        }
        $headers = array_merge(['User-Agent: WhatsAppMediaFetcher/1.0', 'Accept: */*'], $authHeader, $extraHeaders);

        $ch = curl_init();
        curl_setopt_array($ch, [
            CURLOPT_URL => $url,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_FOLLOWLOCATION => true,
            CURLOPT_TIMEOUT => 120,
            CURLOPT_HTTPHEADER => $headers,
        ]);
        $content = curl_exec($ch);
        $err = curl_error($ch);
        $http = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);
        if ($err || $http >= 400) return false;
        return $content;
    }

    public function extensionFromMime($mime) {
        if (!$mime) return null;
        // Remover parámetros del mime type (ej: "audio/ogg; codecs=opus" -> "audio/ogg")
        $baseMime = strtolower(trim(explode(';', $mime)[0]));
        $map = [
            'image/jpeg' => 'jpg',
            'image/png' => 'png',
            'image/gif' => 'gif',
            'image/webp' => 'webp',
            'image/svg+xml' => 'svg',
            'audio/mpeg' => 'mp3',
            'audio/ogg' => 'ogg',
            'audio/opus' => 'ogg',
            'audio/aac' => 'aac',
            'audio/amr' => 'amr',
            'audio/mp4' => 'm4a',
            'video/mp4' => 'mp4',
            'video/3gpp' => '3gp',
            'video/quicktime' => 'mov',
            'video/webm' => 'webm',
            'text/csv' => 'csv',
            'text/plain' => 'txt',
            'application/pdf' => 'pdf',
            'application/msword' => 'doc',
            'application/vnd.openxmlformats-officedocument.wordprocessingml.document' => 'docx',
            'application/vnd.ms-excel' => 'xls',
            'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' => 'xlsx',
            'application/vnd.ms-powerpoint' => 'ppt',
            'application/vnd.openxmlformats-officedocument.presentationml.presentation' => 'pptx',
            'application/zip' => 'zip',
            'application/x-rar-compressed' => 'rar',
            'application/octet-stream' => 'bin',
        ];
        return $map[$baseMime] ?? null;
    }

    public function isImageMime($mime) {
        return strpos($mime, 'image/') === 0;
    }

    public function createThumbnail($src, $dest, $maxW = 400, $maxH = 400) {
        if (!function_exists('getimagesize')) return false;
        $info = @getimagesize($src);
        if (!$info) return false;
        list($w, $h) = $info;
        $mime = $info['mime'];

        switch ($mime) {
            case 'image/jpeg': $srcImg = imagecreatefromjpeg($src); break;
            case 'image/png': $srcImg = imagecreatefrompng($src); break;
            case 'image/gif': $srcImg = imagecreatefromgif($src); break;
            default: return false;
        }

        $ratio = min($maxW / $w, $maxH / $h, 1);
        $nw = (int)($w * $ratio);
        $nh = (int)($h * $ratio);

        $thumb = imagecreatetruecolor($nw, $nh);
        imagecopyresampled($thumb, $srcImg, 0,0,0,0, $nw, $nh, $w, $h);
        imagejpeg($thumb, $dest, 85);
        imagedestroy($thumb);
        imagedestroy($srcImg);
        return true;
    }
}