import { describe, expect, test } from "bun:test";

import { getDateGroup, groupByDate } from "../../../src/web/shared/utils/date-group";

function makeDate(daysAgo: number): string {
  const d = new Date();
  d.setDate(d.getDate() - daysAgo);
  return d.toISOString();
}

describe("getDateGroup", () => {
  test("今天的日期返回 today", () => {
    const now = new Date();
    const result = getDateGroup(now.toISOString(), now);
    expect(result).toBe("today");
  });

  test("昨天的日期返回 yesterday", () => {
    const now = new Date();
    const yesterday = new Date(now);
    yesterday.setDate(yesterday.getDate() - 1);
    const result = getDateGroup(yesterday.toISOString(), now);
    expect(result).toBe("yesterday");
  });

  test("本周内的日期返回 thisWeek", () => {
    const now = new Date();
    const dayOfWeek = now.getDay();
    const mondayOffset = dayOfWeek === 0 ? 6 : dayOfWeek - 1;
    const wednesday = new Date(now);
    wednesday.setDate(now.getDate() - (dayOfWeek === 0 ? 6 : dayOfWeek - 1) + 2);
    if (wednesday > now) {
      const tuesday = new Date(now);
      tuesday.setDate(now.getDate() - mondayOffset + 1);
      if (tuesday < now && tuesday.getDate() !== now.getDate() - 1) {
        const result = getDateGroup(tuesday.toISOString(), now);
        expect(result).toBe("thisWeek");
        return;
      }
    }
    const tuesday = new Date(now);
    tuesday.setDate(now.getDate() - mondayOffset + 1);
    if (tuesday.toDateString() !== now.toDateString()) {
      const yesterday = new Date(now);
      yesterday.setDate(yesterday.getDate() - 1);
      if (tuesday.toDateString() !== yesterday.toDateString()) {
        const result = getDateGroup(tuesday.toISOString(), now);
        expect(result).toBe("thisWeek");
        return;
      }
    }
    expect(true).toBe(true);
  });

  test("本月内的日期返回 thisMonth", () => {
    const now = new Date(2026, 5, 15);
    const earlier = new Date(2026, 5, 3);
    const result = getDateGroup(earlier.toISOString(), now);
    expect(result).toBe("thisMonth");
  });

  test("更早的日期返回 earlier", () => {
    const now = new Date(2026, 5, 15);
    const earlier = new Date(2026, 3, 1);
    const result = getDateGroup(earlier.toISOString(), now);
    expect(result).toBe("earlier");
  });
});

describe("groupByDate", () => {
  test("按 dateField 分组并返回有序结果", () => {
    const now = new Date();
    const items = [
      { id: "1", title: "今天", updatedAt: now.toISOString() },
      { id: "2", title: "昨天", updatedAt: makeDate(1) },
      { id: "3", title: "更早", updatedAt: makeDate(60) },
    ];

    const groups = groupByDate(items, "updatedAt");

    const todayGroup = groups.find((g) => g.key === "today")!;
    expect(todayGroup.items.length).toBe(1);
    expect(todayGroup.items[0]!.id).toBe("1");

    const yesterdayGroup = groups.find((g) => g.key === "yesterday")!;
    expect(yesterdayGroup.items.length).toBe(1);

    const earlierGroup = groups.find((g) => g.key === "earlier")!;
    expect(earlierGroup.items.length).toBe(1);

    const emptyGroups = groups.filter((g) => g.key === "thisWeek" || g.key === "thisMonth");
    emptyGroups.forEach((g) => {
      expect(g.items.length).toBe(0);
    });
  });

  test("空数组返回所有空分组", () => {
    const groups = groupByDate([] as Array<{ updatedAt: string }>, "updatedAt");
    expect(groups.length).toBe(5);
    groups.forEach((g) => {
      expect(g.items.length).toBe(0);
    });
  });
});