import { useReducer } from 'react';

type ActionType = 'update' | 'delete' | 'reset';

interface ChangedData {
  [key: string]: string | number;
}

// 给原始的联系人数组添加id, 没有id的联系人对下即为新添加项，不需要存储添加项
interface Contact {
  //add: { [key: number]: ChangedData }; // 不需要存储
  update: { [key: number]: ChangedData };
  del: ChangedData;
}

const initContact: Contact = { del: {}, update: {} };

const reducer = (
  state: Contact,
  action: { type: ActionType; payload: any },
): Contact => {
  const { type, payload } = action;
  const { update, del } = state;
  let updateCopy = { ...update };
  let delCopy = { ...del };
  switch (type) {
    case 'update':
      if (!updateCopy[payload.idx]) updateCopy[payload.idx] = payload;
      else updateCopy[payload.idx] = { ...updateCopy[payload.idx], ...payload };
      return {
        ...state,
        update: updateCopy,
      };
    case 'delete':
      if (delCopy[payload] === undefined)
        delCopy[payload] = delCopy[payload] = 1;
      if (updateCopy[payload]) delete updateCopy[payload];
      return {
        del: delCopy,
        update: updateCopy,
      };
    case 'reset':
      return {
        del: {},
        update: {},
      };
    default:
      throw new Error(`不匹配的修改类型type-${action.type}`);
  }
};

export default () => useReducer(reducer, initContact);