// Copyright 2026 tamakyi. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package conf

import (
	"testing"
	"time"
)

// setAnnouncement 在测试期间覆盖全局公告配置，结束后恢复。
func setAnnouncement(t *testing.T, content, start, end string) {
	t.Helper()
	old := Announcement
	t.Cleanup(func() { Announcement = old })
	Announcement = announcementConfig{Content: content, Start: start, End: end}
	sanitizeAnnouncement()
}

func mustParse(t *testing.T, layout, value string) time.Time {
	t.Helper()
	parsed, err := time.ParseInLocation(layout, value, time.Local)
	if err != nil {
		t.Fatalf("parse %q: %v", value, err)
	}
	return parsed
}

func TestAnnouncementDisabledWhenContentEmpty(t *testing.T) {
	setAnnouncement(t, "  ", "2026-10-24 00:00", "2026-10-26 00:00")

	if _, ok := Announcement.Active(time.Now()); ok {
		t.Fatal("content 为空时公告应关闭")
	}
}

func TestAnnouncementWindowIsHalfOpen(t *testing.T) {
	setAnnouncement(t, "维护通知", "2026-10-24 00:00", "2026-10-26 00:00")

	start := mustParse(t, "2006-01-02 15:04", "2026-10-24 00:00")
	end := mustParse(t, "2006-01-02 15:04", "2026-10-26 00:00")

	cases := []struct {
		name string
		now  time.Time
		want bool
	}{
		{"开始前一秒", start.Add(-time.Second), false},
		{"开始时刻（闭区间）", start, true},
		{"窗口内", start.Add(12 * time.Hour), true},
		{"结束时刻（开区间）", end, false},
		{"结束后", end.Add(time.Hour), false},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			content, ok := Announcement.Active(c.now)
			if ok != c.want {
				t.Fatalf("Active(%s) = %v, want %v", c.now, ok, c.want)
			}
			if ok && content != "维护通知" {
				t.Fatalf("content = %q, want 维护通知", content)
			}
		})
	}
}

// 只写一侧的边界必须保持「该侧不限」，不能因为另一侧为空就整体失效。
func TestAnnouncementOneSidedWindow(t *testing.T) {
	now := time.Date(2026, 10, 22, 12, 0, 0, 0, time.Local)

	setAnnouncement(t, "只有开始", "2026-10-23 00:00", "")
	if _, ok := Announcement.Active(now); ok {
		t.Fatal("只写 start 且尚未到点时应不展示")
	}
	if _, ok := Announcement.Active(now.Add(48 * time.Hour)); !ok {
		t.Fatal("只写 start 时到点后应一直展示")
	}

	setAnnouncement(t, "只有结束", "", "2026-10-23 00:00")
	if _, ok := Announcement.Active(now); !ok {
		t.Fatal("只写 end 且未到点时应立即展示")
	}
	if _, ok := Announcement.Active(now.Add(48 * time.Hour)); ok {
		t.Fatal("只写 end 时过点后应下线")
	}

	setAnnouncement(t, "一直展示", "", "")
	if _, ok := Announcement.Active(now.AddDate(5, 0, 0)); !ok {
		t.Fatal("起止都留空时应一直展示")
	}
}

func TestAnnouncementTimeFormats(t *testing.T) {
	// 带偏移的 RFC3339 必须按字面时刻解析，而不是再套一层本地时区。
	at, ok := parseAnnouncementTime("2026-10-25T02:00:00+08:00")
	if !ok {
		t.Fatal("RFC3339 应可解析")
	}
	want := time.Date(2026, 10, 24, 18, 0, 0, 0, time.UTC)
	if !at.Equal(want) {
		t.Fatalf("解析结果 = %s, want %s", at.UTC(), want)
	}

	if at, ok := parseAnnouncementTime("2026-10-25"); !ok || at.Hour() != 0 {
		t.Fatalf("纯日期应解析为当天 00:00，got %s ok=%v", at, ok)
	}
	if at, ok := parseAnnouncementTime("2026-10-25 02:00:59"); !ok || at.Second() != 59 {
		t.Fatalf("秒级格式应可解析，got %s ok=%v", at, ok)
	}
	if _, ok := parseAnnouncementTime("2026/10/25 02:00"); ok {
		t.Fatal("错误格式应解析失败")
	}
	if _, ok := parseAnnouncementTime("2026-13-01"); ok {
		t.Fatal("非法月份应解析失败")
	}
}

// 时间写错只关公告，不能让站点起不来；同时必须清空解析结果，避免残留时间窗。
func TestAnnouncementInvalidTimeDisables(t *testing.T) {
	for _, c := range []struct{ name, start, end string }{
		{"start 格式错", "2026/10/25 02:00", ""},
		{"end 格式错", "", "10月26日"},
		{"end 早于 start", "2026-10-26 00:00", "2026-10-25 00:00"},
		{"end 等于 start", "2026-10-25 00:00", "2026-10-25 00:00"},
	} {
		t.Run(c.name, func(t *testing.T) {
			setAnnouncement(t, "内容", c.start, c.end)
			if Announcement.Content != "" {
				t.Fatal("配置无效时公告应被关闭")
			}
			if !Announcement.StartAt.IsZero() || !Announcement.EndAt.IsZero() {
				t.Fatal("配置无效时应清空已解析的时间点")
			}
		})
	}
}