<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type');
if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') { http_response_code(204); exit; }
require_once __DIR__ . '/../../utils/Database.php';
require_once __DIR__ . '/../../utils/Helper.php';
$db = Database::getInstance();
$method = $_SERVER['REQUEST_METHOD'];
if ($method === 'GET') {
    $username = isset($_GET['username']) ? trim($_GET['username']) : '';
    $id = isset($_GET['id']) ? trim($_GET['id']) : '';
    if ($id !== '') {
        $email = $db->fetchOne("SELECT * FROM email WHERE id = ? AND is_deleted = 0", [$id]);
        echo json_encode(['success' => true, 'data' => ['email' => $email]]);
        exit;
    }
    if ($username === '') { http_response_code(400); echo json_encode(['success' => false, 'message' => 'invalid']); exit; }
    $page = isset($_GET['page']) ? max(1, (int)$_GET['page']) : 1;
    $perPage = isset($_GET['perPage']) ? min(100, max(1, (int)$_GET['perPage'])) : 10;
    $offset = ($page - 1) * $perPage;
    $totalRow = $db->fetchOne("SELECT COUNT(*) AS cnt FROM email WHERE rcpt_to = ? AND is_deleted = 0", [$username]);
    $emails = $db->fetchAll("SELECT id, `from`, `to`, subject, `date`, folder, is_read, is_deleted, created_at FROM email WHERE rcpt_to = ? AND is_deleted = 0 ORDER BY `date` DESC LIMIT $perPage OFFSET $offset", [$username]);
    echo json_encode(['success' => true, 'data' => ['emails' => $emails, 'total' => (int)$totalRow['cnt'], 'page' => $page, 'perPage' => $perPage, 'totalPages' => (int)ceil(((int)$totalRow['cnt']) / $perPage)]]);
    exit;
}
if ($method === 'POST') {
    $input = json_decode(file_get_contents('php://input'), true);
    $username = trim($input['username'] ?? '');
    $to = trim($input['to'] ?? '');
    $subject = trim($input['subject'] ?? '');
    $content = $input['content'] ?? '';
    $isDraft = isset($input['isDraft']) ? (bool)$input['isDraft'] : false;
    if ($username === '' || $to === '' || !Helper::validateEmail($to)) { http_response_code(400); echo json_encode(['success' => false, 'message' => 'invalid']); exit; }
    $user = $db->fetchOne("SELECT email FROM user WHERE username = ? AND is_deleted = 0", [$username]);
    $fromEmail = $user ? $user['email'] : ($username . '@test.com');
    $id = Helper::generateId();
    $folder = $isDraft ? 'draft' : 'sent';
    $dateNow = date('Y-m-d H:i:s');
    $raw = "From: {$fromEmail}\r\nTo: {$to}\r\nSubject: {$subject}\r\nDate: {$dateNow}\r\n\r\n{$content}\r\n";
    $db->insert("INSERT INTO email (id, ip, helo, mail_from, rcpt_to, `from`, `to`, subject, `date`, `data`, datagram, `length`, `state`, is_read, folder, created_at, is_deleted) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, NOW(), 0)", [$id, Helper::getClientIp(), 'frontend', $fromEmail, $username, $fromEmail, $to, $subject, $dateNow, $content, $raw, strlen($raw), 1, $isDraft ? 0 : 1, $folder]);
    echo json_encode(['success' => true, 'message' => ($isDraft ? 'draft saved' : 'sent'), 'data' => ['emailId' => $id]]);
    exit;
}
if ($method === 'PUT') {
    $input = json_decode(file_get_contents('php://input'), true);
    $id = trim($input['id'] ?? '');
    $username = trim($input['username'] ?? '');
    $isRead = isset($input['isRead']) ? (int)$input['isRead'] : null;
    $folder = isset($input['folder']) ? trim($input['folder']) : null;
    if ($id === '' || $username === '') { http_response_code(400); echo json_encode(['success' => false, 'message' => 'invalid']); exit; }
    $fields = [];
    $params = [];
    if ($isRead !== null) { $fields[] = "is_read = ?"; $params[] = $isRead; }
    if ($folder !== null) { $fields[] = "folder = ?"; $params[] = $folder; }
    if (empty($fields)) { echo json_encode(['success' => true, 'message' => 'no changes']); exit; }
    $params[] = $id;
    $params[] = $username;
    $db->update("UPDATE email SET " . implode(', ', $fields) . " WHERE id = ? AND rcpt_to = ?", $params);
    echo json_encode(['success' => true, 'message' => 'updated']);
    exit;
}
if ($method === 'DELETE') {
    $id = isset($_GET['id']) ? trim($_GET['id']) : '';
    $username = isset($_GET['username']) ? trim($_GET['username']) : '';
    if ($id === '' || $username === '') { http_response_code(400); echo json_encode(['success' => false, 'message' => 'invalid']); exit; }
    $db->update("UPDATE email SET is_deleted = 1, folder = 'trash' WHERE id = ? AND rcpt_to = ?", [$id, $username]);
    echo json_encode(['success' => true, 'message' => 'deleted']);
    exit;
}
http_response_code(405);
echo json_encode(['success' => false, 'message' => 'method not allowed']);