<?php
session_start();
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type');

if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') { http_response_code(200); exit(); }
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    echo json_encode(['status' => 'error', 'message' => 'Metode tidak diizinkan']);
    exit();
}

require_once 'db_config.php';

$data        = json_decode(file_get_contents('php://input'), true);
$username    = isset($data['username'])     ? trim($data['username'])    : '';
$oldPassword = isset($data['old_password']) ? $data['old_password']      : '';
$newPassword = isset($data['new_password']) ? $data['new_password']      : '';

if (empty($username) || empty($oldPassword) || empty($newPassword)) {
    echo json_encode(['status' => 'error', 'message' => 'Semua field wajib diisi']);
    exit();
}
if (strlen($newPassword) < 6) {
    echo json_encode(['status' => 'error', 'message' => 'Password baru minimal 6 karakter']);
    exit();
}

// Fetch current hashed password
$stmt = $conn->prepare("SELECT id, password FROM users WHERE username = ?");
$stmt->bind_param('s', $username);
$stmt->execute();
$result = $stmt->get_result();

if ($result->num_rows === 0) {
    echo json_encode(['status' => 'error', 'message' => 'User tidak ditemukan']);
    exit();
}

$row = $result->fetch_assoc();
$stmt->close();

if (!password_verify($oldPassword, $row['password'])) {
    echo json_encode(['status' => 'error', 'message' => 'Password lama tidak sesuai']);
    exit();
}

// Update password
$hashed = password_hash($newPassword, PASSWORD_DEFAULT);
$upd    = $conn->prepare("UPDATE users SET password = ? WHERE id = ?");
$upd->bind_param('si', $hashed, $row['id']);

if ($upd->execute()) {
    echo json_encode(['status' => 'success', 'message' => 'Password berhasil diubah']);
} else {
    echo json_encode(['status' => 'error', 'message' => 'Gagal memperbarui password']);
}

$upd->close();
$conn->close();
?>