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

package input

import (
	"testing"
	"time"
)

func TestIntentTracksModifiersAndExpires(t *testing.T) {
	tracker := &IntentTracker{}
	for _, step := range []struct {
		name    string
		pressed bool
		want    Intent
	}{
		{"Down", true, LineIntent}, {"Down", false, LineIntent},
		{"Right", true, CharacterIntent}, {"Control_L", true, OtherIntent},
		{"Right", true, WordIntent}, {"Control_R", true, OtherIntent},
		{"Control_L", false, OtherIntent}, {"Left", true, WordIntent},
		{"Control_R", false, WordIntent}, {"Left", true, CharacterIntent},
		{"s", true, TypingIntent}, {"period", true, TypingIntent},
		{"BackSpace", true, DeleteIntent}, {"Return", true, OtherIntent},
		{"Alt_L", true, OtherIntent}, {"Down", true, OtherIntent},
	} {
		tracker.Observe(NewKeyEvent(0, step.pressed, step.name))
		if got := tracker.RecentIntent(); got != step.want {
			t.Fatalf("%s pressed=%v: %v, want %v", step.name, step.pressed, got, step.want)
		}
	}
	tracker.at = time.Now().Add(-2 * time.Second)
	if tracker.RecentIntent() != NoIntent {
		t.Fatal("stale input reused")
	}
}

func TestIntentTracksClipboardChords(t *testing.T) {
	tracker := &IntentTracker{}
	press := func(name string) Activity {
		tracker.Observe(NewKeyEvent(0, true, name))
		return tracker.RecentInput()
	}
	press("Shift_L")
	if got := press("Right"); got.Intent != CharacterIntent || !got.Selecting {
		t.Fatalf("Shift+Right = %+v", got)
	}
	press("Control_L")
	if got := press("Left"); got.Intent != WordIntent || !got.Selecting {
		t.Fatalf("Ctrl+Shift+Left = %+v", got)
	}
	tracker.Observe(NewKeyEvent(0, false, "Shift_L"))
	for _, tc := range []struct {
		key  string
		want ClipboardAction
	}{
		{"c", CopyAction}, {"x", CutAction}, {"v", PasteAction},
	} {
		if got := press(tc.key); got.Clipboard != tc.want {
			t.Fatalf("Ctrl+%s = %+v", tc.key, got)
		}
	}
	if got := press("Right"); got.Clipboard != NoClipboardAction {
		t.Fatalf("next key retained clipboard action: %+v", got)
	}
	tracker.Observe(NewKeyEvent(0, false, "Control_L"))
	if got := press("v"); got.Clipboard != NoClipboardAction {
		t.Fatalf("plain v = %+v", got)
	}
}

func TestPlainEnterActivityLifetime(t *testing.T) {
	for _, key := range []string{"Return", "KP_Enter"} {
		t.Run(key, func(t *testing.T) {
			tracker := &IntentTracker{}
			tracker.Observe(NewKeyEvent(0, true, key))
			tracker.Observe(NewKeyEvent(0, false, key))
			if activity := tracker.RecentInput(); !activity.PlainEnter || activity.Sequence == 0 || activity.Intent != OtherIntent {
				t.Fatalf("Enter release lost activity: %+v", activity)
			}
			tracker.Observe(NewKeyEvent(0, true, "a"))
			if tracker.RecentInput().PlainEnter {
				t.Fatal("Enter survived the next key")
			}
			tracker.Observe(NewKeyEvent(0, true, key))
			tracker.at = time.Now().Add(-2 * time.Second)
			if tracker.RecentInput().PlainEnter {
				t.Fatal("expired Enter remained active")
			}
			tracker.Observe(NewKeyEvent(0, true, key))
			tracker.Reset()
			if tracker.RecentInput().PlainEnter {
				t.Fatal("reset retained Enter")
			}
		})
	}
	for _, modifier := range []string{"Shift_L", "Control_L", "Alt_L", "Super_L", "ISO_Level3_Shift"} {
		t.Run(modifier, func(t *testing.T) {
			tracker := &IntentTracker{}
			tracker.Observe(NewKeyEvent(0, true, "Return"))
			tracker.Observe(NewKeyEvent(0, true, modifier))
			if tracker.RecentInput().PlainEnter {
				t.Fatal("modifier press retained plain Enter")
			}
			tracker.Observe(NewKeyEvent(0, true, "Return"))
			if tracker.RecentInput().PlainEnter {
				t.Fatal("modified Enter classified as plain Enter")
			}
		})
	}
}

func TestSelectionIntentEndsWithPlainNavigation(t *testing.T) {
	tracker := &IntentTracker{}
	tracker.Observe(NewKeyEvent(0, true, "Shift_L"))
	tracker.Observe(NewKeyEvent(0, true, "Down"))
	if got := tracker.RecentInput(); !got.Selecting || got.Intent != LineIntent {
		t.Fatalf("Shift+Down = %+v", got)
	}
	tracker.Observe(NewKeyEvent(0, false, "Shift_L"))
	tracker.Observe(NewKeyEvent(0, true, "Right"))
	if got := tracker.RecentInput(); got.Selecting || got.Intent != CharacterIntent {
		t.Fatalf("Right = %+v", got)
	}
}

func TestTitleInterruptionTracksFreshPressesAndStopKeys(t *testing.T) {
	tracker := &IntentTracker{}
	for _, step := range []struct {
		name    string
		pressed bool
		repeat  bool
		want    uint64
	}{
		{"a", true, false, 1}, {"a", false, false, 1},
		{"a", true, true, 1}, {"Down", true, false, 2},
		{"Down", true, true, 2}, {"Control_L", true, true, 3},
		{"Control_R", true, true, 4}, {"Escape", true, true, 5},
	} {
		event := NewKeyEvent(0, step.pressed, step.name)
		event.Repeat = step.repeat
		tracker.Observe(event)
		if got := tracker.RecentInput().TitleInterruptionSequence; got != step.want {
			t.Fatalf("%+v: title interruption sequence = %d", step, got)
		}
	}
	tracker.at = time.Now().Add(-2 * time.Second)
	if got := tracker.RecentInput(); got.Intent != NoIntent || got.TitleInterruptionSequence != 5 {
		t.Fatalf("expired activity = %+v", got)
	}
	tracker.Reset()
	if got := tracker.RecentInput().TitleInterruptionSequence; got != 5 {
		t.Fatalf("reset lost interruption history: %d", got)
	}
}

func TestNavigationInputIdentitySurvivesIdle(t *testing.T) {
	tracker := &IntentTracker{}
	tracker.Observe(NewKeyEvent(0, true, "h"))
	tracker.at = time.Now().Add(-2 * time.Second)
	if got := tracker.RecentInput(); got.InputSequence != 1 || got.Sequence != 0 || got.Intent != NoIntent {
		t.Fatalf("idle input identity = %+v", got)
	}
}

func TestPlainCharacterArrowsExcludeOtherNavigation(t *testing.T) {
	for _, modifier := range []string{"", "Shift_L", "Control_L", "Alt_L", "Super_L", "ISO_Level3_Shift"} {
		for _, key := range []string{"Left", "Right", "KP_Left", "Home", "End", "Up", "a"} {
			var tracker IntentTracker
			if modifier != "" {
				tracker.Observe(NewKeyEvent(1, true, modifier))
			}
			tracker.Observe(NewKeyEvent(2, true, key))
			want := modifier == "" && (key == "Left" || key == "Right" || key == "KP_Left")
			if got := tracker.RecentInput().PlainCharacterArrow; got != want {
				t.Fatalf("%s+%s hint = %t, want %t", modifier, key, got, want)
			}
			tracker.Observe(NewKeyEvent(2, false, key))
			if tracker.RecentInput().PlainCharacterArrow != want {
				t.Fatal("releasing arrow discarded presentation intent")
			}
			tracker.Reset()
			if tracker.RecentInput().PlainCharacterArrow {
				t.Fatal("reset retained phonetic arrow")
			}
		}
	}
}