<?php
/**
 * api/_bootstrap.php
 * ------------------
 * Shared setup for every endpoint under /api: loads config, applies error
 * settings, and provides small HTTP / JSON helpers.
 */

require_once __DIR__ . '/../config.php';

if (cfg('runtime.show_errors')) {
    ini_set('display_errors', '1');
    ini_set('display_startup_errors', '1');
    error_reporting(E_ALL);
} else {
    error_reporting(0);
}

/** Send a JSON response and stop. */
function json_out($data, $status = 200) {
    http_response_code($status);
    header('Content-Type: application/json; charset=utf-8');
    header('Access-Control-Allow-Origin: *');
    header('Cache-Control: no-cache, must-revalidate, max-age=0');
    echo json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
    exit;
}

/** Plain-text response and stop (used by the lyrics endpoint). */
function text_out($text, $status = 200) {
    http_response_code($status);
    header('Content-Type: text/plain; charset=utf-8');
    header('Access-Control-Allow-Origin: *');
    header('Cache-Control: no-cache, must-revalidate, max-age=0');
    echo $text;
    exit;
}

/**
 * Perform an HTTP GET and return the body (or null on failure).
 * Falls back to file_get_contents when cURL is unavailable.
 */
function http_get($url, $timeout = 5, $headers = []) {
    if ($url === '') return null;

    if (function_exists('curl_init')) {
        $ch = curl_init($url);
        curl_setopt_array($ch, [
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_CONNECTTIMEOUT => (int) $timeout,
            CURLOPT_TIMEOUT        => (int) $timeout,
            CURLOPT_FOLLOWLOCATION => true,
            CURLOPT_MAXREDIRS      => 3,
            CURLOPT_USERAGENT      => cfg('runtime.user_agent'),
        ]);
        if (!empty($headers)) {
            curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
        }
        $body = curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
        curl_close($ch);
        if ($body === false || $code >= 400) return null;
        return $body;
    }

    // Fallback without cURL.
    $ctx = stream_context_create([
        'http' => [
            'timeout' => (int) $timeout,
            'header'  => implode("\r\n", array_merge(['User-Agent: ' . cfg('runtime.user_agent')], $headers)),
            'ignore_errors' => true,
        ],
        'ssl' => ['verify_peer' => true, 'verify_peer_name' => true],
    ]);
    $body = @file_get_contents($url, false, $ctx);
    return ($body === false) ? null : $body;
}

/**
 * Read a value out of a decoded-JSON structure using dot notation.
 * Supports array indexes: "a.b.0.c".
 */
function dot_get($data, $path, $default = null) {
    if ($path === '' || $path === null) return $default;
    $node = $data;
    foreach (explode('.', $path) as $key) {
        if (is_array($node) && array_key_exists($key, $node)) {
            $node = $node[$key];
        } elseif (is_object($node) && isset($node->$key)) {
            $node = $node->$key;
        } else {
            return $default;
        }
    }
    return $node;
}

/** Read the artist/title the browser sends to artwork/lyrics endpoints. */
function request_track() {
    $artist = $_POST['artist'] ?? $_GET['artist'] ?? '';
    $title  = $_POST['title']  ?? $_GET['title']  ?? '';
    return [trim((string) $artist), trim((string) $title)];
}