<?php
/**
 * api/upload_audio.php
 * POST: upload an audio file for a specific prayer key.
 * Admin only. Replaces any existing file for that key.
 *
 * POST params:
 *   key   — audio key string (alphanumeric + underscores)
 *   audio — uploaded file (MP3, M4A, OGG, WAV)
 *
 * Returns JSON: {"key": "...", "ext": "mp3"} or {"error": "..."}
 */
require_once __DIR__ . '/../config/db.php';
require_once __DIR__ . '/../includes/auth.php';

header('Content-Type: application/json');
require_auth();

if (!has_role('admin')) {
    http_response_code(403);
    echo json_encode(['error' => 'Permission denied']);
    exit;
}

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['error' => 'Method not allowed']);
    exit;
}

$key = trim($_POST['key'] ?? '');
if (!preg_match('/^[a-z0-9_]+$/', $key) || strlen($key) > 100) {
    http_response_code(400);
    echo json_encode(['error' => 'Invalid audio key']);
    exit;
}

if (!isset($_FILES['audio']) || $_FILES['audio']['error'] !== UPLOAD_ERR_OK) {
    $codes = [
        UPLOAD_ERR_INI_SIZE  => 'File exceeds server limit',
        UPLOAD_ERR_FORM_SIZE => 'File exceeds form limit',
        UPLOAD_ERR_PARTIAL   => 'File only partially uploaded',
        UPLOAD_ERR_NO_FILE   => 'No file uploaded',
    ];
    $code = $_FILES['audio']['error'] ?? UPLOAD_ERR_NO_FILE;
    http_response_code(400);
    echo json_encode(['error' => $codes[$code] ?? 'Upload error']);
    exit;
}

$file     = $_FILES['audio'];
$max_size = 50 * 1024 * 1024; // 50 MB

if ($file['size'] > $max_size) {
    http_response_code(400);
    echo json_encode(['error' => 'File too large (max 50 MB)']);
    exit;
}

$finfo   = new finfo(FILEINFO_MIME_TYPE);
$mime    = $finfo->file($file['tmp_name']);
$allowed = [
    'audio/mpeg'      => 'mp3',
    'audio/mp3'       => 'mp3',
    'audio/mp4'       => 'm4a',
    'audio/x-m4a'     => 'm4a',
    'audio/ogg'       => 'ogg',
    'audio/wav'       => 'wav',
    'audio/x-wav'     => 'wav',
    'audio/wave'      => 'wav',
    'audio/webm'      => 'webm',
];

if (!isset($allowed[$mime])) {
    http_response_code(400);
    echo json_encode(['error' => 'Invalid format. Allowed: MP3, M4A, OGG, WAV']);
    exit;
}

$ext       = $allowed[$mime];
$audio_dir = UPLOADS_DIR . 'audio/';

if (!is_dir($audio_dir)) {
    mkdir($audio_dir, 0755, true);
}

// Delete any existing file for this key (regardless of extension)
foreach (glob($audio_dir . $key . '.*') ?: [] as $old) {
    unlink($old);
}

$dest = $audio_dir . $key . '.' . $ext;

if (!move_uploaded_file($file['tmp_name'], $dest)) {
    http_response_code(500);
    echo json_encode(['error' => 'Failed to save file']);
    exit;
}

echo json_encode(['key' => $key, 'ext' => $ext]);