/**
 * 数据状态管理 - DataStore
 * 功能：使用 Zustand 管理全局数据状态，包括账户、账单、预算、统计数据的 CRUD
 * 状态流转：每个 action 遵循 loading -> 请求 -> success/error -> loading=false 的流程
 * 级联刷新：CRUD 操作成功后自动重新拉取列表和仪表盘汇总数据，保证跨页面数据一致性
 * API 依赖：accountsApi、recordsApi、budgetsApi、statisticsApi
 */
import { create } from 'zustand';
import type { Account, Record, Budget, DashboardSummary, TrendStat, MonthlyCompare } from '../types';
import { accountsApi, recordsApi, budgetsApi, statisticsApi } from '../services';

/**
 * DataState 接口 - 定义全局数据状态的结构
 */
interface DataState {
  // ===== 数据实体 =====
  accounts: Account[];           // 账户列表
  records: Record[];             // 账单记录列表
  budgets: Budget[];             // 预算配置列表
  dashboardSummary: DashboardSummary | null;  // 仪表盘汇总数据（余额、收支、预算使用率）
  trendData: TrendStat[];        // 趋势统计数据（用于折线图）
  monthlyCompare: MonthlyCompare | null;      // 月度对比数据（用于柱状对比图）
  loading: boolean;              // 全局加载状态
  error: string | null;          // 全局错误信息
  
  // ===== Actions - 数据查询 =====
  fetchAccounts: () => Promise<void>;
  fetchRecords: (params?: {
    accountId?: number;
    type?: 'income' | 'expense';
    category?: string;
    startDate?: string;
    endDate?: string;
  }) => Promise<void>;
  fetchBudgets: (month?: string) => Promise<void>;
  fetchDashboardSummary: () => Promise<void>;
  fetchTrendData: (startDate: string, endDate: string) => Promise<void>;
  fetchMonthlyCompare: (month: string) => Promise<void>;
  
  // ===== Actions - 数据操作 =====
  createRecord: (data: any) => Promise<void>;
  updateRecord: (id: number, data: any) => Promise<void>;
  deleteRecord: (id: number) => Promise<void>;
  createBudget: (data: any) => Promise<void>;
  updateBudget: (id: number, data: any) => Promise<void>;
  deleteBudget: (id: number) => Promise<void>;
  clearError: () => void;
}

export const useDataStore = create<DataState>((set, get) => ({
  accounts: [],
  records: [],
  budgets: [],
  dashboardSummary: null,
  trendData: [],
  monthlyCompare: null,
  loading: false,
  error: null,

  // API: GET /api/accounts - 获取账户列表
  fetchAccounts: async () => {
    set({ loading: true, error: null });
    try {
      const data = await accountsApi.getAccounts();
      set({ accounts: data });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: GET /api/records - 获取账单记录列表（支持多条件筛选）
  fetchRecords: async (params) => {
    set({ loading: true, error: null });
    try {
      const data = await recordsApi.getRecords(params);
      set({ records: data });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: GET /api/budgets - 获取预算列表（可按月份筛选）
  fetchBudgets: async (month) => {
    set({ loading: true, error: null });
    try {
      const data = await budgetsApi.getBudgets(month);
      set({ budgets: data });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: GET /api/statistics/dashboard - 获取仪表盘汇总数据
  // 同时更新 accounts 状态，因为汇总数据中包含账户信息
  fetchDashboardSummary: async () => {
    set({ loading: true, error: null });
    try {
      const data = await statisticsApi.getDashboardSummary();
      set({ dashboardSummary: data, accounts: data.accounts });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: fetchTrendData - 获取日期趋势数据（用于折线图）
  fetchTrendData: async (startDate: string, endDate: string) => {
    set({ loading: true, error: null });
    try {
      const data = await statisticsApi.getTrendStats(startDate, endDate);
      set({ trendData: data });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: fetchMonthlyCompare - 获取本月与上月对比数据（用于柱状对比图）
  fetchMonthlyCompare: async (month: string) => {
    set({ loading: true, error: null });
    try {
      const data = await statisticsApi.getMonthlyCompare(month);
      set({ monthlyCompare: data });
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: POST /api/records - 创建账单记录，成功后级联刷新列表和仪表盘
  // 级联刷新目的：确保其他页面（如 Dashboard、Budget）能立即看到最新数据
  createRecord: async (data) => {
    set({ loading: true, error: null });
    try {
      await recordsApi.createRecord(data);
      await get().fetchRecords();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: PUT /api/records/:id - 更新账单记录，成功后级联刷新
  updateRecord: async (id, data) => {
    set({ loading: true, error: null });
    try {
      await recordsApi.updateRecord(id, data);
      await get().fetchRecords();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: DELETE /api/records/:id - 删除账单记录，成功后级联刷新
  deleteRecord: async (id) => {
    set({ loading: true, error: null });
    try {
      await recordsApi.deleteRecord(id);
      await get().fetchRecords();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: POST /api/budgets - 创建预算，成功后级联刷新预算列表和仪表盘
  createBudget: async (data) => {
    set({ loading: true, error: null });
    try {
      await budgetsApi.createBudget(data);
      await get().fetchBudgets();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: PUT /api/budgets/:id - 更新预算，成功后级联刷新
  updateBudget: async (id, data) => {
    set({ loading: true, error: null });
    try {
      await budgetsApi.updateBudget(id, data);
      await get().fetchBudgets();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // API: DELETE /api/budgets/:id - 删除预算，成功后级联刷新
  deleteBudget: async (id) => {
    set({ loading: true, error: null });
    try {
      await budgetsApi.deleteBudget(id);
      await get().fetchBudgets();
      await get().fetchDashboardSummary();
    } catch (error) {
      set({ error: (error as Error).message });
    } finally {
      set({ loading: false });
    }
  },

  // 清除全局错误信息，用于错误状态重置
  clearError: () => set({ error: null }),
}));