<?php
/**
 * LOGIN ENDPOINT - User Authentication API
 * ========================================
 * 
 * DESKRIPSI:
 * ==========
 * Endpoint untuk autentikasi user dengan username dan password.
 * Setelah login sukses, akan setup session lengkap dengan:
 * - User information dan group details
 * - License data yang dapat diakses user
 * - Map configuration settings
 * - Login history logging
 * 
 * METHOD: POST
 * ENDPOINT: /auth/login
 * CONTENT-TYPE: application/json
 * 
 * REQUEST BODY:
 * =============
 * {
 *   "username": "string",
 *   "password": "string"
 * }
 * 
 * RESPONSE SUCCESS (200):
 * =======================
 * {
 *   "token": "string",
 *   "user": "string",
 *   "fullName": "string",
 *   "userGroupID": "string",
 *   "map_settings": {
 *     "latitude": number,
 *     "longitude": number,
 *     "zoom": number,
 *     "GMT": number
 *   }
 * }
 * 
 * RESPONSE ERROR (400/401/500):
 * =============================
 * {
 *   "error": "string"
 * }
 * 
 * SECURITY:
 * =========
 * - Password di-hash dengan sha1(md5()) sesuai sistem legacy
 * - Token di-generate dengan cryptographically secure method
 * - Prepared statement untuk mencegah SQL injection
 * - Session management untuk maintain login state
 * 
 * AUTHOR: Rodhi
 * DATE: 2026-01-19
 * VERSION: 1.0
 */

// Simple CORS headers - No custom headers needed
if (!headers_sent()) {
    header("Access-Control-Allow-Origin: *");
    header("Access-Control-Allow-Methods: POST, OPTIONS");
    header("Access-Control-Allow-Headers: Content-Type");
    header("Content-Type: application/json");
}

// Handle preflight OPTIONS request
if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    http_response_code(200);
    exit;
}

require_once __DIR__.'/../models/database.php';
require_once __DIR__.'/../helpers/database_helper.php';
require_once __DIR__.'/../helpers/session_helper.php';

// Enable error logging untuk debugging (uncomment jika perlu debug)
// ini_set('log_errors', 1);
// ini_set('error_log', __DIR__.'/../../login_error.log');

// Ambil raw input dari request body
$rawInput = file_get_contents('php://input');
$data = json_decode($rawInput, true);

// Debug: Log input untuk debugging (uncomment jika perlu debug)
// error_log("Login attempt - Raw input: " . $rawInput);
// error_log("Login attempt - Parsed data: " . json_encode($data));
// error_log("Login attempt - User Agent: " . (isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : 'not set'));
// error_log("Login attempt - IP: " . (isset($_SERVER['REMOTE_ADDR']) ? $_SERVER['REMOTE_ADDR'] : 'not set'));

// Validasi input data
if (!$data || !isset($data['username']) || !isset($data['password'])) {
    http_response_code(400);
    echo json_encode(['error' => 'Username and password are required']);
    // Debug version dengan data yang diterima:
    // echo json_encode(['error' => 'Username and password are required', 'received_data' => $data]);
    exit;
}

try {
    // Debug: tampilkan raw query dan parameters (uncomment jika perlu debug)
    // $table = 'tbusers';
    // $where = 'userName = ?';
    // $params = [$data['username']];
    // $pdo = Database::getConnection();
    // $sql = "SELECT * FROM {$table} WHERE {$where}";
    // error_log("Debug - Raw query: " . $sql);
    // error_log("Debug - Parameters: " . json_encode($params));
    // error_log("Debug - Input data: " . json_encode($data));
    // error_log("Debug - Password hash: " . sha1(md5($data['password'])));
    
    // Cari user berdasarkan username
    $user = Database::findOne('tbusers', 'userName = ?', [$data['username']]);

    // Validasi user existence
    if (!$user) {
        // Debug: Log failed login attempt
        // error_log("Login failed - User not found: " . $data['username']);
        
        http_response_code(401);
        echo json_encode(['error' => 'User not found']);
        exit;
    }

    // Validasi password dengan hash yang sesuai sistem legacy
    $inputPasswordHash = sha1(md5($data['password']));
    if ($user['newpass'] !== $inputPasswordHash) {
        // Debug: Log password mismatch
        // error_log("Login failed - Password mismatch for user: " . $data['username']);
        // error_log("Expected hash: " . $user['newpass']);
        // error_log("Provided hash: " . $inputPasswordHash);
        
        http_response_code(401);
        echo json_encode(['error' => 'Invalid password']);
        exit;
    }

    // Debug: Log successful authentication
    // error_log("Login successful - User authenticated: " . $data['username']);

    // Mulai session untuk user
    session_start();
    $_SESSION['user'] = $user['userName'];
    $_SESSION['username'] = $user['userName']; // ← TAMBAH INI untuk consistency

    // Setup user session dengan semua data yang diperlukan
    // Ini akan mengisi session dengan user groups, licenses, dll
    SessionHelper::dbUserLogin($user['userName']);
    
    // Log history login untuk audit trail
    SessionHelper::infHistoryLogin();
    
    // Setup map configuration untuk user
    SessionHelper::checkViewMap();

    // Generate secure token untuk API authentication
    $token = DatabaseHelper::generateSecureToken(32);
    
    // Simpan token ke database untuk authentication
    $tokenSaved = SessionHelper::saveToken($user['userName'], $token);
    
    // Debug: Log token generation dan penyimpanan
    // error_log("Login completed - Token generated for user: " . $user['userName']);
    // error_log("Token saved to database: " . ($tokenSaved ? "Success" : "Failed"));
    // error_log("Session data: " . json_encode([
    //     'username' => $_SESSION['username'] ?? 'not set',
    //     'fullName' => $_SESSION['fullName'] ?? 'not set',
    //     'userGroupID' => $_SESSION['userGroupID'] ?? 'not set',
    //     'license_count' => count($_SESSION['license'] ?? [])
    // ]));

    // Return response dengan informasi lengkap user
    echo json_encode([
        'token' => $token,
        'user' => $user['userName'],
        'fullName' => isset($_SESSION['fullName']) ? $_SESSION['fullName'] : '',
        'userGroupID' => isset($_SESSION['userGroupID']) ? $_SESSION['userGroupID'] : '',
        'map_settings' => [
            'latitude' => $_SESSION['map_init_lat'],
            'longitude' => $_SESSION['map_init_lng'], 
            'zoom' => $_SESSION['map_init_zoom'],
            'GMT' => $_SESSION['GMT']
        ]
        // Debug: Tambahkan info token untuk debugging
        // 'token_saved' => $tokenSaved,
        // 'license_count' => count($_SESSION['license'] ?? [])
    ]);
    
} catch (Exception $e) {
    // Log error untuk debugging
    error_log("Login error: " . $e->getMessage());
    error_log("Login error trace: " . $e->getTraceAsString());
    
    http_response_code(500);
    echo json_encode([
        'error' => 'Database connection failed: ' . $e->getMessage()
        // Debug version dengan stack trace:
        // 'error' => 'Database connection failed: ' . $e->getMessage(),
        // 'trace' => $e->getTraceAsString()
    ]);
}