// 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"

	"github.com/tamakyi/TamaBox/internal/i18n"
)

// setAnnouncement 在测试期间覆盖全局公告配置，结束后恢复。
// 不设 Timezone，即走默认的东八区。
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()
}

// setAnnouncementConfig 用完整配置覆盖，供分语言 / 时区用例使用。
func setAnnouncementConfig(t *testing.T, cfg announcementConfig) {
	t.Helper()
	old := Announcement
	t.Cleanup(func() { Announcement = old })
	Announcement = cfg
	sanitizeAnnouncement()
}

func mustParseIn(t *testing.T, layout, value string) time.Time {
	t.Helper()
	loc, err := time.LoadLocation(defaultAnnouncementZone)
	if err != nil {
		t.Fatalf("load zone %s: %v", defaultAnnouncementZone, err)
	}
	parsed, err := time.ParseInLocation(layout, value, loc)
	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(), i18n.LangZhCN); ok {
		t.Fatal("所有语言文案都为空时公告应关闭")
	}
}

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

	start := mustParseIn(t, "2006-01-02 15:04", "2026-10-24 00:00")
	end := mustParseIn(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, i18n.LangZhCN)
			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 := mustParseIn(t, "2006-01-02 15:04", "2026-10-22 12:00")

	setAnnouncement(t, "只有开始", "2026-10-23 00:00", "")
	if _, ok := Announcement.Active(now, i18n.LangZhCN); 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), i18n.LangZhCN); !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, i18n.LangZhCN); !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), i18n.LangZhCN); 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), i18n.LangZhCN); !ok {
		t.Fatal("起止都留空时应一直展示")
	}
}

// 分语言文案：配了就用自己的，没配回退 content；content 也没配则该语言不显示。
func TestAnnouncementLanguageSelection(t *testing.T) {
	setAnnouncementConfig(t, announcementConfig{
		Content:     "fallback",
		ContentZhCN: "简中",
		ContentEn:   "english",
		ContentJa:   "日本語",
	})

	cases := []struct{ lang, want string }{
		{i18n.LangZhCN, "简中"},
		{i18n.LangEn, "english"},
		{i18n.LangJa, "日本語"},
		{i18n.LangZhTW, "fallback"}, // 没配繁中 → 回退默认文案
		{"en-US", "english"},        // Resolve 会归一化
	}
	for _, c := range cases {
		got, ok := Announcement.Active(time.Now(), c.lang)
		if !ok || got != c.want {
			t.Fatalf("Active(lang=%s) = %q ok=%v, want %q", c.lang, got, ok, c.want)
		}
	}

	// 只配英文、content 留空：简中访客不应看到英文公告。
	setAnnouncementConfig(t, announcementConfig{ContentEn: "english only"})
	if _, ok := Announcement.Active(time.Now(), i18n.LangZhCN); ok {
		t.Fatal("该语言未配文案且无默认文案时不应展示")
	}
	if got, ok := Announcement.Active(time.Now(), i18n.LangEn); !ok || got != "english only" {
		t.Fatalf("英文应正常展示，got %q ok=%v", got, ok)
	}
}

func TestAnnouncementTimeFormats(t *testing.T) {
	loc, err := time.LoadLocation(defaultAnnouncementZone)
	if err != nil {
		t.Fatalf("load zone: %v", err)
	}

	// 带偏移的 RFC3339 必须按字面时刻解析，而不是再套一层默认时区。
	at, ok := parseAnnouncementTime("2026-10-25T02:00:00+08:00", loc)
	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", loc); !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", loc); !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", loc); ok {
		t.Fatal("错误格式应解析失败")
	}
	if _, ok := parseAnnouncementTime("2026-13-01", loc); ok {
		t.Fatal("非法月份应解析失败")
	}
}

// 裸时间必须按东八区解释：运维写「10-25 02:00」指北京时间，
// 而容器里的 time.Local 是 UTC（旧实现整体偏 8 小时）。
func TestAnnouncementBareTimeUsesBeijing(t *testing.T) {
	setAnnouncement(t, "维护通知", "2026-10-25 02:00", "")

	want := time.Date(2026, 10, 24, 18, 0, 0, 0, time.UTC) // 北京 10-25 02:00
	if !Announcement.StartAt.Equal(want) {
		t.Fatalf("裸时间应按 +08:00 解释，got %s, want %s", Announcement.StartAt.UTC(), want)
	}
	if _, offset := Announcement.StartAt.Zone(); offset != 8*60*60 {
		t.Fatalf("解析后的偏移 = %d 秒, want 28800", offset)
	}
}

// timezone 显式指定时以它为准，不能继续套东八区。
func TestAnnouncementTimezoneOverride(t *testing.T) {
	setAnnouncementConfig(t, announcementConfig{
		Content:  "维护通知",
		Start:    "2026-10-25 00:00",
		Timezone: "UTC",
	})

	want := time.Date(2026, 10, 25, 0, 0, 0, 0, time.UTC)
	if !Announcement.StartAt.Equal(want) {
		t.Fatalf("timezone=UTC 时应按 UTC 解析，got %s", Announcement.StartAt.UTC())
	}

	setAnnouncementConfig(t, announcementConfig{
		Content:  "维护通知",
		Start:    "2026-10-25 00:00",
		Timezone: "America/New_York",
	})
	// 纽约 10-25 00:00 = UTC 10-25 04:00（EDT，UTC-4）
	wantNY := time.Date(2026, 10, 25, 4, 0, 0, 0, time.UTC)
	if !Announcement.StartAt.Equal(wantNY) {
		t.Fatalf("timezone=America/New_York 解析错误，got %s", Announcement.StartAt.UTC())
	}
}

// 时区名写错和日期写错一样：只关公告，不阻断启动。
func TestAnnouncementInvalidTimezoneDisables(t *testing.T) {
	setAnnouncementConfig(t, announcementConfig{
		Content:  "维护通知",
		Start:    "2026-10-25 00:00",
		Timezone: "Mars/Olympus",
	})

	if Announcement.Content != "" {
		t.Fatal("时区无效时公告应被关闭")
	}
}

// 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")
			}
		})
	}
}