// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package notification

import (
	"testing"
	"time"
)

func TestPresenterSavesHistoryAndEnforcesMaximumSize(t *testing.T) {
	now := time.Unix(1_800_000_000, 0)
	presenter := NewPresenterAt(func() time.Time { return now })
	for number := 0; number < historySize+2; number++ {
		presenter.Save(time.Unix(int64(number), 0).Format("2006"))
		now = now.Add(time.Second)
	}
	entries := presenter.Entries()
	if len(entries) != historySize {
		t.Fatalf("history length = %d, want %d", len(entries), historySize)
	}
	if entries[0].Source != SourceGeneric {
		t.Fatalf("first source = %q, want %q", entries[0].Source, SourceGeneric)
	}
}

func TestPresenterNavigationMatchesReferenceBoundaries(t *testing.T) {
	now := time.Unix(1_800_000_000, 0)
	presenter := NewPresenterAt(func() time.Time { return now })
	presenter.Save("first")
	presenter.Save("second")

	assertMessages := func(t *testing.T, got []string, want ...string) {
		t.Helper()
		if len(got) != len(want) {
			t.Fatalf("message count = %d, want %d: %q", len(got), len(want), got)
		}
		for index := range want {
			if got[index] != want[index] {
				t.Fatalf("message %d = %q, want %q", index, got[index], want[index])
			}
		}
	}
	t.Run("last", func(t *testing.T) {
		assertMessages(t, presenter.PresentLast(), "second 0 seconds ago")
	})
	t.Run("previous then top", func(t *testing.T) {
		assertMessages(t, presenter.PresentPrevious(), "first 0 seconds ago")
		assertMessages(t, presenter.PresentPrevious(), MessageListTop, "first 0 seconds ago")
	})
	t.Run("next then bottom", func(t *testing.T) {
		assertMessages(t, presenter.PresentNext(), "second 0 seconds ago")
		assertMessages(t, presenter.PresentNext(), MessageListBottom, "second 0 seconds ago")
		assertMessages(t, presenter.PresentNext(), MessageListBottom, "second 0 seconds ago")
	})
	t.Run("empty", func(t *testing.T) {
		empty := NewPresenterAt(func() time.Time { return now })
		assertMessages(t, empty.PresentLast(), MessageNoMessages)
		assertMessages(t, empty.PresentPrevious(), MessageNoMessages)
		assertMessages(t, empty.PresentNext(), MessageNoMessages)
	})
}

func TestPresenterStartsAtLatestNotification(t *testing.T) {
	now := time.Unix(1_800_000_000, 0)
	presenter := NewPresenterAt(func() time.Time { return now })
	presenter.Save("first")
	presenter.Save("second")

	assertMessages(t, presenter.PresentPrevious(), "first 0 seconds ago")
}

func TestPresenterRemovalKeepsHistoryNavigationValid(t *testing.T) {
	for _, removeAt := range []int{0, 1, 2} {
		t.Run(time.Duration(removeAt).String(), func(t *testing.T) {
			now := time.Unix(1_800_000_000, 0)
			presenter := NewPresenterAt(func() time.Time { return now })
			entries := []Entry{presenter.Save("first"), presenter.Save("second"), presenter.Save("third")}
			presenter.PresentPrevious()
			presenter.PresentPrevious()
			if !presenter.Remove(entries[removeAt]) {
				t.Fatal("notification was not removed")
			}
			want := "first 0 seconds ago"
			if removeAt == 0 {
				want = "second 0 seconds ago"
			}
			assertMessages(t, presenter.PresentPrevious(), MessageListTop, want)
			presenter.PresentNext()
		})
	}
}

func assertMessages(t *testing.T, got []string, want ...string) {
	t.Helper()
	if len(got) != len(want) {
		t.Fatalf("message count = %d, want %d: %q", len(got), len(want), got)
	}
	for index := range want {
		if got[index] != want[index] {
			t.Fatalf("message %d = %q, want %q", index, got[index], want[index])
		}
	}
}

func TestRelativeTimeUsesReferenceRounding(t *testing.T) {
	now := time.Unix(1_800_000_000, 0)
	for _, test := range []struct {
		elapsed time.Duration
		want    string
	}{
		{90 * time.Second, "2 minutes ago"},
		{150 * time.Second, "2 minutes ago"},
		{89 * time.Second, "1 minute ago"},
		{90 * time.Minute, "2 hours ago"},
		{90 * time.Hour, "4 days ago"},
	} {
		if got := relativeTime(now.Add(-test.elapsed), now); got != test.want {
			t.Fatalf("relativeTime(%s) = %q, want %q", test.elapsed, got, test.want)
		}
	}
}