import { Transaction, Message, BillReminder } from '../types';

// API基础配置
const getApiUrl = (): string => {
  return process.env.API_URL || 'http://localhost:8000';
};

const getAuthToken = (): string | null => {
  return localStorage.getItem('auth_token');
};

// 统一响应格式
interface ApiResponse<T = any> {
  code: number;
  msg?: string;
  message?: string;
  result?: T;
}

// 分页响应格式
interface PaginatedResponse<T> {
  items: T[];
  skip: number;
  total: number;
}

// 通用请求函数
async function request<T>(
  endpoint: string,
  options: RequestInit = {}
): Promise<T> {
  const token = getAuthToken();
  const apiUrl = getApiUrl();
  const url = `${apiUrl}${endpoint}`;
  
  console.log(`请求地址: ${url}`);
  
  const defaultHeaders: HeadersInit = {
    'Content-Type': 'application/json',
  };
  
  if (token) {
    defaultHeaders['Authorization'] = `Bearer ${token}`;
  }

  const config: RequestInit = {
    ...options,
    headers: {
      ...defaultHeaders,
      ...options.headers,
    },
  };

  try {
    const response = await fetch(url, config);
    
    const data: ApiResponse<T> = await response.json();
    
    if (!response.ok || (data.code && data.code !== 200)) {
      const errorMsg = data.msg || data.message || `HTTP error! status: ${response.status}`;
      throw new Error(errorMsg);
    }

    return data.result as T;
  } catch (error) {
    console.error('API请求错误:', error);
    throw error;
  }
}

// ==================== 用户认证接口 ====================

/**
 * 登录或注册
 */
export async function loginOrRegister(openid: string, mobile: string): Promise<{
  token: string;
  user: any;
}> {
  const apiUrl = getApiUrl();
  console.log(`请求地址: ${apiUrl}/wx/loginOrRegister`);
  
  const response = await fetch(`${apiUrl}/wx/loginOrRegister`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({ openid, mobile }),
  });
  
  const data = await response.json();
  
  if (data.code === 200 && data.result?.token) {
    // 保存token到localStorage
    localStorage.setItem('auth_token', data.result.token);
  }
  
  return data.result;
}

/**
 * 获取用户信息
 */
export async function getUserProfile(): Promise<any> {
  return request<any>('/wx/profile', {
    method: 'GET',
  });
}

// ==================== 交易记录接口 ====================

/**
 * 创建交易记录
 */
export async function createTransaction(data: {
  item: string;
  amount: number;
  type: 'expense' | 'income';
  category: string;
  date: string;
  timestamp: number;
}): Promise<Transaction> {
  return request<Transaction>('/bill/transactions/', {
    method: 'POST',
    body: JSON.stringify(data),
  });
}

/**
 * 查询交易记录列表（分页）
 */
export async function getTransactions(params?: {
  skip?: number;
  limit?: number;
  type?: 'expense' | 'income';
  category?: string;
  start_date?: string;
  end_date?: string;
  month?: string;
}): Promise<PaginatedResponse<Transaction>> {
  const queryString = new URLSearchParams(
    Object.entries(params || {}).reduce((acc, [key, value]) => {
      if (value !== undefined) {
        acc[key] = String(value);
      }
      return acc;
    }, {} as Record<string, string>)
  ).toString();

  return request<PaginatedResponse<Transaction>>(
    `/bill/transactions/${queryString ? `?${queryString}` : ''}`
  );
}

/**
 * 更新交易记录
 */
export async function updateTransaction(
  id: string,
  data: Partial<{
    item: string;
    amount: number;
    type: 'expense' | 'income';
    category: string;
    date: string;
    timestamp: number;
  }>
): Promise<Transaction> {
  return request<Transaction>(`/bill/transactions/${id}`, {
    method: 'PUT',
    body: JSON.stringify(data),
  });
}

/**
 * 删除交易记录
 */
export async function deleteTransaction(id: string): Promise<void> {
  return request<void>(`/bill/transactions/${id}`, {
    method: 'DELETE',
  });
}

// ==================== 聊天消息接口 ====================

/**
 * 创建聊天消息
 */
export async function createMessage(data: {
  role: 'user' | 'assistant';
  content: string;
  timestamp: number;
  transaction_id?: string;
}): Promise<Message> {
  return request<Message>('/bill/messages/', {
    method: 'POST',
    body: JSON.stringify(data),
  });
}

/**
 * 查询聊天消息列表
 */
export async function getMessages(params?: {
  skip?: number;
  limit?: number;
  role?: 'user' | 'assistant';
  start_timestamp?: number;
  end_timestamp?: number;
}): Promise<PaginatedResponse<Message>> {
  const queryString = new URLSearchParams(
    Object.entries(params || {}).reduce((acc, [key, value]) => {
      if (value !== undefined) {
        acc[key] = String(value);
      }
      return acc;
    }, {} as Record<string, string>)
  ).toString();

  return request<PaginatedResponse<Message>>(
    `/bill/messages/${queryString ? `?${queryString}` : ''}`
  );
}

/**
 * 删除消息
 */
export async function deleteMessage(id: string): Promise<void> {
  return request<void>(`/bill/messages/${id}`, {
    method: 'DELETE',
  });
}

// ==================== 账单提醒接口 ====================

/**
 * 创建账单提醒
 */
export async function createReminder(data: {
  title: string;
  amount?: number;
  frequency: 'monthly' | 'once';
  target_date: string;
}): Promise<BillReminder> {
  return request<BillReminder>('/bill/reminders/', {
    method: 'POST',
    body: JSON.stringify(data),
  });
}

/**
 * 查询账单提醒列表
 */
export async function getReminders(params?: {
  skip?: number;
  limit?: number;
  frequency?: 'monthly' | 'once';
  is_completed?: boolean;
  month?: string;
}): Promise<PaginatedResponse<BillReminder>> {
  const queryString = new URLSearchParams(
    Object.entries(params || {}).reduce((acc, [key, value]) => {
      if (value !== undefined) {
        acc[key] = String(value);
      }
      return acc;
    }, {} as Record<string, string>)
  ).toString();

  return request<PaginatedResponse<BillReminder>>(
    `/bill/reminders/${queryString ? `?${queryString}` : ''}`
  );
}

/**
 * 更新账单提醒
 */
export async function updateReminder(
  id: string,
  data: Partial<{
    title: string;
    amount?: number;
    frequency: 'monthly' | 'once';
    target_date: string;
  }>
): Promise<BillReminder> {
  return request<BillReminder>(`/bill/reminders/${id}`, {
    method: 'PUT',
    body: JSON.stringify(data),
  });
}

/**
 * 切换提醒完成状态
 */
export async function toggleReminder(
  id: string
): Promise<{ id: string; is_completed: boolean }> {
  return request<{ id: string; is_completed: boolean }>(
    `/bill/reminders/${id}/toggle`,
    {
      method: 'PATCH',
    }
  );
}

/**
 * 删除账单提醒
 */
export async function deleteReminder(id: string): Promise<void> {
  return request<void>(`/bill/reminders/${id}`, {
    method: 'DELETE',
  });
}


// ==================== 导出所有API ====================
export default {
  // 用户认证
  loginOrRegister,
  getUserProfile,
  
  // 交易记录
  createTransaction,
  getTransactions,
  updateTransaction,
  deleteTransaction,
  
  // 聊天消息
  createMessage,
  getMessages,
  deleteMessage,
  
  // 账单提醒
  createReminder,
  getReminders,
  updateReminder,
  toggleReminder,
  deleteReminder,
};