<?php

function load_env_file(string $path): void {
    if (!is_file($path)) return;

    foreach (file($path, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES) ?: [] as $line) {
        $line = trim($line);
        if ($line === '' || str_starts_with($line, '#')) continue;

        [$key, $value] = array_pad(explode('=', $line, 2), 2, '');
        $key = trim($key);
        if ($key === '') continue;

        $value = trim($value);
        if (
            strlen($value) >= 2
            && (($value[0] === '"' && $value[-1] === '"') || ($value[0] === "'" && $value[-1] === "'"))
        ) {
            $value = substr($value, 1, -1);
        }

        $_ENV[$key] = $value;
        putenv($key . '=' . $value);
    }
}

function env_value(string $key, ?string $default = null): string {
    $value = $_ENV[$key] ?? getenv($key);
    if ($value === false || $value === null || $value === '') {
        if ($default !== null) return $default;
        throw new RuntimeException('Missing required environment value: ' . $key);
    }
    return (string)$value;
}

function env_bool(string $key, bool $default = false): bool {
    $value = strtolower(env_value($key, $default ? 'true' : 'false'));
    return in_array($value, ['1', 'true', 'yes', 'on'], true);
}

function env_list(string $key): array {
    $value = env_value($key, '');
    return array_values(array_filter(array_map('trim', explode(',', $value)), fn($v) => $v !== ''));
}

load_env_file(__DIR__ . '/.env');

define('DEV_MODE',      env_bool('DEV_MODE'));
define('CLIENT_ID',     env_value('CLIENT_ID'));
define('REDIRECT_URI',  env_value('REDIRECT_URI'));
define('AUTHORIZE_URI', env_value('AUTHORIZE_URI'));
define('TOKEN_URI',     env_value('TOKEN_URI'));
define('GRAPHQL_URI',   env_value('GRAPHQL_URI'));
define('ADMIN_USER_IDS', env_list('ADMIN_USER_IDS'));

function session_start_safe(): void {
    if (session_status() === PHP_SESSION_NONE) {
        session_set_cookie_params([
            'lifetime' => 0,
            'path'     => '/',
            'secure'   => false, // set to true in production (HTTPS)
            'httponly' => true,
            'samesite' => 'Lax',
        ]);
        session_start();
    }
}

function default_return_path(): string {
    $script = str_replace('\\', '/', $_SERVER['SCRIPT_NAME'] ?? '/index.php');
    $base   = rtrim(dirname(dirname($script)), '/');
    return ($base === '' ? '' : $base) . '/index.php';
}

function safe_return_path(?string $value): string {
    $value = trim((string)$value);
    if ($value === '') return default_return_path();

    $parts = parse_url($value);
    if ($parts === false) return default_return_path();
    if (isset($parts['host'])) {
        $currentHost = strtolower(explode(':', $_SERVER['HTTP_HOST'] ?? '')[0]);
        if (strtolower($parts['host']) !== $currentHost) return default_return_path();
    } elseif (str_starts_with($value, '//')) {
        return default_return_path();
    }

    $path = $parts['path'] ?? '';
    if ($path === '') $path = default_return_path();
    if ($path[0] !== '/') $path = '/' . ltrim($path, '/');

    $query = isset($parts['query']) ? '?' . $parts['query'] : '';
    return $path . $query;
}

function current_return_path(): string {
    return safe_return_path($_SERVER['REQUEST_URI'] ?? null);
}

function auth_start_href(?string $returnPath = null): string {
    return 'auth/start.php?return=' . rawurlencode($returnPath ?? current_return_path());
}

function fflogs_graphql_user_query(string $query, string $token): array {
    $payload = json_encode(['query' => $query]);
    if ($payload === false) {
        return ['error' => 'Could not encode GraphQL payload'];
    }

    if (function_exists('curl_init')) {
        $ch = curl_init(GRAPHQL_URI);
        curl_setopt_array($ch, [
            CURLOPT_POST           => true,
            CURLOPT_POSTFIELDS     => $payload,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HTTPHEADER     => [
                'Content-Type: application/json',
                'Authorization: Bearer ' . $token,
            ],
            CURLOPT_SSL_VERIFYPEER => !DEV_MODE,
        ]);
        $body = curl_exec($ch);
        $err  = curl_error($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);
        if ($err) return ['error' => $err, 'status' => $code];
        return ['body' => $body, 'status' => $code];
    }

    $context = stream_context_create([
        'http' => [
            'method'  => 'POST',
            'content' => $payload,
            'header'  => implode("\r\n", [
                'Content-Type: application/json',
                'Authorization: Bearer ' . $token,
            ]),
            'timeout' => 30,
        ],
        'ssl' => [
            'verify_peer'      => !DEV_MODE,
            'verify_peer_name' => !DEV_MODE,
        ],
    ]);
    $body = file_get_contents(GRAPHQL_URI, false, $context);
    if ($body === false) return ['error' => 'GraphQL request failed'];
    return ['body' => $body, 'status' => 200];
}

function fetch_current_fflogs_user(string $token): ?array {
    $result = fflogs_graphql_user_query('query { userData { currentUser { id name } } }', $token);
    if (!empty($result['error'])) {
        $_SESSION['fflogs_user_error'] = $result['error'];
        return null;
    }

    $data = json_decode((string)($result['body'] ?? ''), true);
    $user = $data['data']['userData']['currentUser'] ?? null;
    if (!is_array($user) || empty($user['id'])) {
        $_SESSION['fflogs_user_error'] = $data['errors'][0]['message'] ?? 'Could not read current FFLogs user';
        return null;
    }

    return [
        'id'   => (string)$user['id'],
        'name' => (string)($user['name'] ?? ''),
    ];
}

function current_fflogs_user(bool $forceRefresh = false): ?array {
    if (!$forceRefresh && !empty($_SESSION['fflogs_user']) && is_array($_SESSION['fflogs_user'])) {
        return $_SESSION['fflogs_user'];
    }
    if (empty($_SESSION['access_token']) || (($_SESSION['token_expires'] ?? 0) <= time())) {
        return null;
    }

    $user = fetch_current_fflogs_user($_SESSION['access_token']);
    if ($user !== null) {
        $_SESSION['fflogs_user'] = $user;
        unset($_SESSION['fflogs_user_error']);
    }
    return $user;
}

function is_admin_user(): bool {
    $user = current_fflogs_user();
    return $user !== null && in_array((string)$user['id'], ADMIN_USER_IDS, true);
}