<?php
/**
 * Endpoint: /api/version/media-url.php
 * Parámetros: id (media id) o url (direct url), opcional download=1 para proxy y forzar descarga
 * - Si se solicita JSON (Accept: application/json) la endpoint requiere autenticación y devuelve {success:true,url:...}
 * - Si se accede mediante GET desde navegador, redirige (302) al URL del media (no requiere sesión)
 */
require_once __DIR__ . '/../../config/config.php';

$isGet = $_SERVER['REQUEST_METHOD'] === 'GET';
$accept = $_SERVER['HTTP_ACCEPT'] ?? '';
$wantsJson = strpos($accept, 'application/json') !== false;

// Requerir autenticación sólo para peticiones no-GET o cuando se solicita JSON (API/AJAX)
if (!$isGet || $wantsJson) {
    requireAuthentication();
}

header('Content-Type: application/json; charset=utf-8');

$mediaId = $_GET['id'] ?? $_POST['id'] ?? null;
$providedUrl = $_GET['url'] ?? $_POST['url'] ?? null;
$download = isset($_GET['download']) && $_GET['download'] === '1';

if (!$mediaId && !$providedUrl) {
    http_response_code(400);
    echo json_encode(['success' => false, 'error' => 'Se requiere id o url']);
    exit;
}

$mediaUrl = null;

if ($providedUrl) {
    $mediaUrl = $providedUrl;
} else {
    $token = getConfigFromDB('whatsapp_token', '');
    $apiUrl = rtrim(getConfigFromDB('whatsapp_api_url', 'https://graph.facebook.com/v22.0/'), '/');
    $endpoint = "{$apiUrl}/{$mediaId}";

    $ch = curl_init();
    curl_setopt_array($ch, [
        CURLOPT_URL => $endpoint,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_HTTPHEADER => [ 'Authorization: Bearer ' . $token ],
        CURLOPT_TIMEOUT => 15,
    ]);
    $response = curl_exec($ch);
    $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $err = curl_error($ch);
    curl_close($ch);

    if ($err) {
        http_response_code(502);
        echo json_encode(['success' => false, 'error' => 'Error comunicando con Graph API', 'detail' => $err]);
        exit;
    }

    $decoded = json_decode($response, true);
    if ($httpCode >= 400 || !$decoded) {
        http_response_code($httpCode ?: 500);
        echo json_encode(['success' => false, 'error' => 'Graph API error', 'response' => $decoded]);
        exit;
    }

    $mediaUrl = $decoded['url'] ?? ($decoded['data'][0]['url'] ?? null);
    if (!$mediaUrl) {
        http_response_code(404);
        echo json_encode(['success' => false, 'error' => 'No se recibió URL del media', 'raw' => $decoded]);
        exit;
    }
}

// Si se solicitó JSON, devolver la URL
if ($wantsJson) {
    echo json_encode(['success' => true, 'url' => $mediaUrl]);
    exit;
}

// Si se pidió proxy (download=1), traer el contenido y retornarlo como descarga
if ($download) {
    $ch = curl_init();
    curl_setopt_array($ch, [
        CURLOPT_URL => $mediaUrl,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_FOLLOWLOCATION => true,
        CURLOPT_TIMEOUT => 60,
    ]);
    $content = curl_exec($ch);
    $info = curl_getinfo($ch);
    $err = curl_error($ch);
    curl_close($ch);

    if ($err) {
        http_response_code(502);
        header('Content-Type: application/json; charset=utf-8');
        echo json_encode(['success' => false, 'error' => 'Error al descargar el archivo', 'detail' => $err]);
        exit;
    }

    // Cabeceras para descarga
    header_remove('Content-Type');
    header('Cache-Control: public, max-age=3600');
    if (!empty($info['content_type'])) header('Content-Type: ' . $info['content_type']);
    if (!empty($info['size_download'])) header('Content-Length: ' . $info['size_download']);
    $filename = basename(parse_url($mediaUrl, PHP_URL_PATH) ?: 'file');
    header('Content-Disposition: attachment; filename="' . $filename . '"');
    echo $content;
    exit;
}

// Por defecto redirigir al URL (navegador hará la descarga o mostrará la imagen)
header('Cache-Control: public, max-age=3600');
header('Location: ' . $mediaUrl, true, 302);
exit;