<?php
// 登录 / 注册
require __DIR__ . '/includes/init.php';
$pageTitle = __('login.title');

$next  = $_GET['next'] ?? '';
$mode  = $_GET['mode'] ?? 'login';
$invite = trim($_GET['inv'] ?? '');
$err   = '';
$ok    = '';

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    verifyCsrf();

    if (isset($_POST['login'])) {
        $u = trim($_POST['username'] ?? '');
        $pw = $_POST['password'] ?? '';
        $stmt = db()->prepare('SELECT * FROM ' . tn('users') . ' WHERE username = ?');
        $stmt->execute([$u]);
        $row = $stmt->fetch();
        if ($row && password_verify($pw, $row['password'])) {
            $_SESSION['user_id'] = $row['id'];
            unset($_SESSION['csrf']);
            redirect($next ?: 'index.php');
        }
        $err = __('login.err_login_failed');
    }

    if (isset($_POST['register'])) {
        $u   = trim($_POST['username'] ?? '');
        $pw  = $_POST['password'] ?? '';
        $pw2 = $_POST['password2'] ?? '';
        $em  = trim($_POST['email'] ?? '');
        $cap = strtoupper(trim($_POST['captcha'] ?? ''));
        // 邀请码：优先使用表单填写，其次使用 URL 参数
        $postInvite = isset($_POST['invite_code']) ? trim($_POST['invite_code']) : null;
        $invite = $postInvite !== null ? $postInvite : trim($_GET['inv'] ?? '');

        // 自研图形验证码：一次性校验后清空
        $sessCap = isset($_SESSION['captcha']) ? strtoupper($_SESSION['captcha']) : '';
        unset($_SESSION['captcha']);
        if ($cap === '' || $cap !== $sessCap) {
            $err = __('login.err_captcha_wrong');
        }
        elseif (strlen($u) < 3)                 $err = __('login.err_username_short');
        elseif (strlen($pw) < 6)            $err = __('login.err_password_short');
        elseif ($pw !== $pw2)               $err = __('login.err_password_mismatch');
        elseif (!filter_var($em, FILTER_VALIDATE_EMAIL)) $err = __('login.err_email_invalid');
        // 若用户在表单里手动填写了邀请码，则必须校验通过
        elseif ($postInvite !== null && $postInvite !== '' && getInviterIdByCode($postInvite) === 0) {
            $err = __('login.err_invite_invalid');
        }

        // 单 IP 每日最多注册 2 个账号
        if ($err === '') {
            $ip = getClientIp();
            if (regCountToday($ip) >= 2) {
                $err = __('login.err_ip_limit');
            }
        }

        if ($err === '') {
            $chk = db()->prepare('SELECT id FROM ' . tn('users') . ' WHERE username = ?');
            $chk->execute([$u]);
            if ($chk->fetch()) {
                $err = __('login.err_username_exists');
            } else {
                $hash = password_hash($pw, PASSWORD_DEFAULT);
                $myCode = genInviteCode();
                db()->prepare('INSERT INTO ' . tn('users') . ' (username,password,email,reg_ip,invite_code,verified,created_at) VALUES (?,?,?,?,?,0,NOW())')
                   ->execute([$u, $hash, $em, $ip, $myCode]);
                $id = db()->lastInsertId();
                // 邀请奖励：通过他人邀请码注册，给邀请人加积分
                if ($invite !== '') {
                    $invId = getInviterIdByCode($invite);
                    if ($invId > 0 && $invId != $id) {
                        db()->prepare('UPDATE ' . tn('users') . ' SET invited_by = ? WHERE id = ?')
                           ->execute([$invId, $id]);
                        $invPts = max(0, (int) getSetting('points_invite', '20'));
                        if ($invPts > 0) {
                            addPoints($invId, 'invite', $invPts, '邀请好友 ' . $u . ' 注册成功');
                        }
                    }
                }
                $_SESSION['user_id'] = $id;
                // 发送邮箱验证邮件（不阻塞注册：失败也可正常使用）
                $sendRes = sendVerifyMail($id);
                $_SESSION['verify_notice'] = $sendRes['ok'] ? 'sent' : 'fail';
                unset($_SESSION['csrf']);
                redirect($next ?: 'index.php');
            }
        }
    }
}

require 'includes/header.php';
?>
<section class="section auth-section">
    <div class="auth-card">
        <div class="auth-tabs">
            <a href="login.php?mode=login" class="<?= $mode==='login'?'active':'' ?>"><?= __('login.tab_login') ?></a>
            <a href="login.php?mode=register" class="<?= $mode==='register'?'active':'' ?>"><?= __('login.tab_register') ?></a>
        </div>

        <?php if ($err): ?><p class="form-err"><?= h($err) ?></p><?php endif; ?>

        <?php if ($mode === 'login'): ?>
            <form method="post" action="" class="auth-form">
                <?= csrfField() ?>
                <label><?= __('auth.username') ?><input type="text" name="username" required></label>
                <label><?= __('auth.password') ?><input type="password" name="password" required></label>
                <button type="submit" name="login" class="btn btn-primary"><?= __('login.btn_login') ?></button>
            </form>
        <?php else: ?>
            <form method="post" action="" class="auth-form">
                <?= csrfField() ?>
                <label><?= __('auth.username') ?><input type="text" name="username" placeholder="<?= __('login.username_placeholder') ?>" required></label>
                <label><?= __('login.label_email') ?> *<input type="email" name="email" placeholder="<?= __('login.email_placeholder') ?>" required></label>
                <div class="captcha-box">
                    <img src="captcha.php" alt="CAPTCHA" class="captcha-img" onclick="this.src='captcha.php?'+Date.now()" title="<?= __('login.captcha_hint') ?>">
                    <label><?= __('login.label_captcha') ?><input type="text" name="captcha" maxlength="4" autocomplete="off" placeholder="<?= __('login.captcha_placeholder') ?>" required></label>
                </div>
                <label><?= __('auth.password') ?><input type="password" name="password" placeholder="<?= __('login.pwd_placeholder') ?>" required></label>
                <label><?= __('auth.confirm_password') ?><input type="password" name="password2" required></label>
                <label><?= __('login.label_invite') ?><input type="text" name="invite_code" placeholder="<?= __('login.invite_placeholder') ?>" value="<?= h($invite) ?>"></label>
                <button type="submit" name="register" class="btn btn-primary"><?= __('login.btn_register') ?></button>
                <p class="form-tip"><?= __('login.register_tip') ?></p>
            </form>
        <?php endif; ?>
    </div>
</section>
<?php require 'includes/footer.php'; ?>