import { useState } from 'react';
import { Link, useNavigate } from 'react-router-dom';
import { App as AntdApp, Button, Form, Input } from 'antd';
import { LockOutlined, MailOutlined, UserOutlined } from '@ant-design/icons';
import axios from 'axios';
import AuthLayout from '@/layouts/AuthLayout';
import { apiErrorMessage } from '@/services/api';
import { authApi } from '@/services/auth';
import { authToken } from '@/services/authToken';
import { emailFormatRule } from '@/utils/validators';

interface RegisterFormValues {
    display_name?: string;
    email: string;
    password: string;
    password_confirmation: string;
}

/** 注册页，契约见 docs/api/auth.md §2；密码长度与复杂度由服务端唯一校验，前端不自行放宽或收窄 */
const RegisterPage = () => {
    const navigate = useNavigate();
    const { message } = AntdApp.useApp();
    const [form] = Form.useForm<RegisterFormValues>();
    const [submitting, setSubmitting] = useState(false);

    const handleFinish = async (values: RegisterFormValues) => {
        setSubmitting(true);
        try {
            const session = await authApi.register({
                email: values.email.trim(),
                password: values.password,
                password_confirmation: values.password_confirmation,
                display_name: values.display_name?.trim() || undefined,
            });
            // 注册成功即在同一事务创建用户、个人工作空间和登录会话
            authToken.set(session.access_token);
            message.success('注册成功，已进入你的工作空间');
            navigate('/online-products', { replace: true });
        } catch (error) {
            // 重复邮箱返回 409 EMAIL_ALREADY_REGISTERED，落到邮箱字段上提示
            if (axios.isAxiosError(error) && error.response?.status === 409) {
                form.setFields([
                    { name: 'email', errors: ['该邮箱已注册，请直接登录'] },
                ]);
            } else {
                message.error(apiErrorMessage(error));
            }
        } finally {
            setSubmitting(false);
        }
    };

    return (
        <AuthLayout
            title="注册"
            subtitle="创建账户后自动创建个人工作空间，注册即登录"
            footer={
                <>
                    已有账户？<Link to="/login">直接登录</Link>
                </>
            }
        >
            <Form<RegisterFormValues>
                form={form}
                layout="vertical"
                requiredMark={false}
                onFinish={handleFinish}
            >
                <Form.Item
                    name="display_name"
                    label="显示名称"
                    extra="选填，最多 80 个字符"
                    rules={[{ max: 80, message: '显示名称最多 80 个字符' }]}
                >
                    <Input
                        prefix={
                            <UserOutlined
                                style={{ color: 'var(--text-secondary)' }}
                            />
                        }
                        placeholder="选填"
                        maxLength={80}
                        autoComplete="nickname"
                    />
                </Form.Item>
                <Form.Item
                    name="email"
                    label="邮箱"
                    rules={[
                        { required: true, message: '请输入邮箱' },
                        emailFormatRule,
                    ]}
                >
                    <Input
                        prefix={
                            <MailOutlined
                                style={{ color: 'var(--text-secondary)' }}
                            />
                        }
                        placeholder="请输入邮箱"
                        autoComplete="email"
                    />
                </Form.Item>
                <Form.Item
                    name="password"
                    label="密码"
                    extra="长度与复杂度规则以服务端安全校验为准"
                    rules={[{ required: true, message: '请输入密码' }]}
                >
                    <Input.Password
                        prefix={
                            <LockOutlined
                                style={{ color: 'var(--text-secondary)' }}
                            />
                        }
                        placeholder="请输入密码"
                        autoComplete="new-password"
                    />
                </Form.Item>
                <Form.Item
                    name="password_confirmation"
                    label="确认密码"
                    dependencies={['password']}
                    rules={[
                        { required: true, message: '请再次输入密码' },
                        ({ getFieldValue }) => ({
                            validator(_, value) {
                                if (
                                    !value ||
                                    getFieldValue('password') === value
                                ) {
                                    return Promise.resolve();
                                }
                                return Promise.reject(
                                    new Error('两次输入的密码不一致'),
                                );
                            },
                        }),
                    ]}
                >
                    <Input.Password
                        prefix={
                            <LockOutlined
                                style={{ color: 'var(--text-secondary)' }}
                            />
                        }
                        placeholder="请再次输入密码"
                        autoComplete="new-password"
                    />
                </Form.Item>
                <Form.Item style={{ marginBottom: 0, marginTop: 8 }}>
                    <Button
                        type="primary"
                        htmlType="submit"
                        block
                        loading={submitting}
                    >
                        创建账户
                    </Button>
                </Form.Item>
            </Form>
        </AuthLayout>
    );
};

export default RegisterPage;