// Cthulhu screen reader.
// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along with
// this program. If not, see <https://www.gnu.org/licenses/gpl-3.0.html>.

package app

import (
	"context"
	"log/slog"
	"reflect"
	"testing"
	"time"

	"git.stormux.org/storm/cthulhu/internal/atspi"
	"git.stormux.org/storm/cthulhu/internal/input"
	"git.stormux.org/storm/cthulhu/internal/review"
)

func TestProcessEventsSpeaksChangedCaretLines(t *testing.T) {
	speech := &fakeSpeechQueue{spoken: make(chan string, 2)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 3)}
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	completed := make(chan struct{})
	go func() {
		processEvents(ctx, slog.New(slog.DiscardHandler), speech, adapter, 0)
		close(completed)
	}()

	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshot("/accessible/terminal", "", "terminal", "", "First line"))
	select {
	case text := <-speech.spoken:
		if text != "First line" {
			t.Fatalf("spoken text = %q, want %q", text, "First line")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for first caret speech")
	}

	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshot("/accessible/terminal", "", "terminal", "", "First line"))
	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshot("/accessible/terminal", "", "terminal", "", "Second line"))
	select {
	case text := <-speech.spoken:
		if text != "Second line" {
			t.Fatalf("spoken text = %q, want %q", text, "Second line")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for second caret speech")
	}

	cancel()
	select {
	case <-completed:
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for event loop to stop")
	}
}

func TestProcessEventsSuppressesCaretAfterEditableTextChange(t *testing.T) {
	speech := &fakeSpeechQueue{spoken: make(chan string, 3)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 4)}
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	completed := make(chan struct{})
	go func() {
		processEvents(ctx, slog.New(slog.DiscardHandler), speech, adapter, 0)
		close(completed)
	}()

	paragraph := atspi.Snapshot{Path: "/writer/paragraph", Role: "paragraph", Editable: true,
		Text: "Hello", CaretCharacter: "o"}
	adapter.events <- atspi.NewEvent(atspi.FocusEvent, paragraph)
	<-speech.spoken
	adapter.events <- atspi.NewEventWithPayload(atspi.TextInsertedEvent, paragraph, "o")
	if got := <-speech.spoken; got != "o" {
		t.Fatalf("insert speech = %q", got)
	}
	adapter.events <- atspi.NewEvent(atspi.CaretEvent, paragraph)
	adapter.events <- atspi.NewEventWithPayload(atspi.TextInsertedEvent,
		atspi.Snapshot{Path: "/status", Role: "label"}, "status update")

	select {
	case got := <-speech.spoken:
		t.Fatalf("unexpected duplicate or status speech: %q", got)
	case <-time.After(30 * time.Millisecond):
	}

	cancel()
	<-completed
}

func TestProcessEventsReadOnlyComboUsesNameInsteadOfEditorCaret(t *testing.T) {
	speech := &fakeSpeechQueue{spoken: make(chan string, 16)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 16)}
	combo := atspi.Snapshot{BusName: ":1.7", Path: "/combo", Role: "combo box", Name: "Classic Doom", Focused: true}
	adapter.events <- atspi.NewEvent(atspi.FocusEvent, combo)
	editor := atspi.Snapshot{BusName: combo.BusName, Path: "/combo/editor", Role: "text", Text: "Funny Pack - Classic Doom",
		BrailleLine: "Funny Pack - Classic Doom", TextCaretKnown: true, Editable: true, ReadOnly: true,
		Focused: true, ReadOnlyCombo: combo.ID()}
	for _, value := range []string{"Funny Pack - Classic Doom", "Toby Doom", "Classic Doom"} {
		editor.Text, editor.BrailleLine = value, value
		adapter.events <- atspi.NewEvent(atspi.CaretEvent, editor)
		combo.Name = value
		adapter.events <- atspi.NewEvent(atspi.AccessibleNameEvent, combo)
	}
	close(adapter.events)
	processEvents(context.Background(), slog.New(slog.DiscardHandler), speech, adapter, 0)
	close(speech.spoken)
	var got []string
	for text := range speech.spoken {
		got = append(got, text)
	}
	want := []string{"Classic Doom, combo box", "Funny Pack - Classic Doom", "Toby Doom", "Classic Doom"}
	if !reflect.DeepEqual(got, want) {
		t.Fatalf("combo speech = %q, want %q", got, want)
	}
}

func TestReadOnlyComboCaretRequiresExactOwnedCombo(t *testing.T) {
	combo := atspi.Snapshot{BusName: ":1.7", Path: "/combo", Role: "combo box"}
	for _, test := range []struct {
		name  string
		owner atspi.ObjectID
		skip  bool
	}{
		{"owned", combo.ID(), true},
		{"different combo", atspi.NewObjectID(combo.BusName, "/other-combo"), false},
		{"different provider", atspi.NewObjectID(":1.8", combo.Path), false},
		{"ordinary editor", atspi.ObjectID{}, false},
	} {
		t.Run(test.name, func(t *testing.T) {
			state := &eventLoopState{}
			state.current, state.focusedID = combo, combo.ID()
			handler := accessibilityEventHandler{state: state, logger: slog.New(slog.DiscardHandler), debounce: time.Hour}
			event := atspi.NewEvent(atspi.CaretEvent, atspi.Snapshot{BusName: combo.BusName, Path: "/editor", Role: "text", ReadOnlyCombo: test.owner})
			handler.handleCaret(event, input.Activity{}, input.NoIntent)
			defer state.pending.clear()
			if skipped := state.pending.caret.event.Type == ""; skipped != test.skip {
				t.Fatalf("caret skipped = %v, want %v", skipped, test.skip)
			}
		})
	}
}

func TestTerminalCaretSeedsReviewFocusWithoutFocusEvent(t *testing.T) {
	// A reader started while the terminal already has focus may never see
	// a focus-gain event. Caret movement from the focused terminal is the
	// evidence flat review needs to anchor to it.
	worker, err := review.NewWorker(&documentLineCapturer{calls: make(chan documentLineCaptureCall, 1)}, time.Second)
	if err != nil {
		t.Fatal(err)
	}
	state := &eventLoopState{}
	defer state.pending.clear()
	handler := accessibilityEventHandler{state: state, logger: slog.New(slog.DiscardHandler), objectReview: worker, debounce: time.Hour}
	terminal := atspi.Snapshot{BusName: ":1.9", Path: "/terminal", Role: "terminal", Focused: true}
	// Output churn without user typing must not claim review focus.
	handler.handleCaret(atspi.NewEvent(atspi.CaretEvent, terminal), input.Activity{}, input.NoIntent)
	if got := worker.Focus(); got.Valid() {
		t.Fatalf("review focus seeded without typing = %+v", got)
	}
	handler.handleCaret(atspi.NewEvent(atspi.CaretEvent, terminal), input.Activity{}, input.TypingIntent)
	if got := worker.Focus(); got != terminal.ID() {
		t.Fatalf("review focus = %+v, want terminal %+v", got, terminal.ID())
	}
	if state.focusedID != terminal.ID() || state.current.ID() != terminal.ID() {
		t.Fatalf("focused state = %+v/%+v, want terminal", state.focusedID, state.current.ID())
	}
	// An unfocused terminal caret must not steal review focus.
	other := atspi.Snapshot{BusName: ":1.9", Path: "/other-terminal", Role: "terminal"}
	handler.handleCaret(atspi.NewEvent(atspi.CaretEvent, other), input.Activity{}, input.TypingIntent)
	if got := worker.Focus(); got != terminal.ID() {
		t.Fatalf("review focus after unfocused caret = %+v, want %+v", got, terminal.ID())
	}
	// Another widget in the same application can retain a stale focused
	// bit. Its caret must not move review away from the known focus.
	other.Focused = true
	handler.handleCaret(atspi.NewEvent(atspi.CaretEvent, other), input.Activity{}, input.TypingIntent)
	if got := worker.Focus(); got != state.focusedID {
		t.Fatalf("stale focused bit split review and input ownership: %+v != %+v", got, state.focusedID)
	}
}

func TestProcessEventsSpeaksCaretCharacters(t *testing.T) {
	speech := &fakeSpeechQueue{spoken: make(chan string, 3)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 3)}
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	completed := make(chan struct{})
	go func() {
		processEvents(ctx, slog.New(slog.DiscardHandler), speech, adapter, 0)
		close(completed)
	}()

	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshotWithCaretCharacter(
		"/accessible/terminal", "", "terminal", "", "prompt ls", "l",
	))
	select {
	case text := <-speech.spoken:
		if text != "l" {
			t.Fatalf("spoken text = %q, want %q", text, "l")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for first caret character speech")
	}
	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshotWithCaretCharacter(
		"/accessible/terminal", "", "terminal", "", "prompt ll", "l",
	))
	select {
	case text := <-speech.spoken:
		if text != "l" {
			t.Fatalf("repeated caret character = %q, want l", text)
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for repeated caret character speech")
	}

	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshotWithCaretCharacter(
		"/accessible/terminal", "", "terminal", "", "prompt ls", "s",
	))
	select {
	case text := <-speech.spoken:
		if text != "s" {
			t.Fatalf("spoken text = %q, want %q", text, "s")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for second caret character speech")
	}

	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshotWithCaretCharacter(
		"/accessible/terminal", "", "terminal", "", "prompt ls", " ",
	))
	select {
	case text := <-speech.spoken:
		if text != "space" {
			t.Fatalf("spoken caret space = %q, want %q", text, "space")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for caret space speech")
	}

	cancel()
	select {
	case <-completed:
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for event loop to stop")
	}
}

func TestProcessEventsTextChangeCancelsPendingCaretLine(t *testing.T) {
	speech := &fakeSpeechQueue{spoken: make(chan string, 1)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 2)}
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	completed := make(chan struct{})
	go func() {
		processEvents(ctx, slog.New(slog.DiscardHandler), speech, adapter, time.Hour)
		close(completed)
	}()

	terminal := atspi.NewSnapshot("/accessible/terminal", "", "terminal", "", "prompt l")
	adapter.events <- atspi.NewEvent(atspi.CaretEvent, terminal)
	adapter.events <- atspi.NewEventWithPayload(atspi.TextInsertedEvent, terminal, "l")

	select {
	case text := <-speech.spoken:
		if text != "l" {
			t.Fatalf("spoken text = %q, want %q", text, "l")
		}
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for inserted text speech")
	}

	select {
	case text := <-speech.spoken:
		t.Fatalf("unexpected additional speech: %q", text)
	default:
	}

	cancel()
	select {
	case <-completed:
	case <-time.After(time.Second):
		t.Fatal("timed out waiting for event loop to stop")
	}
}

func TestCaretEventRequestsCharacterVoice(t *testing.T) {
	queue := &autocompleteRequestQueue{requests: make(chan speechRequest, 1)}
	adapter := &fakeAdapter{events: make(chan atspi.Event, 1)}
	ctx, cancel := context.WithCancel(context.Background())
	done := make(chan struct{})
	go func() { defer close(done); processEvents(ctx, slog.New(slog.DiscardHandler), queue, adapter, 0) }()
	defer func() { cancel(); <-done }()
	adapter.events <- atspi.NewEvent(atspi.CaretEvent, atspi.NewSnapshotWithCaretCharacter("/terminal", "", "terminal", "", "Ab", "A"))
	select {
	case request := <-queue.requests:
		if request.Text != "A" || !request.Character {
			t.Fatalf("caret request = %+v", request)
		}
	case <-time.After(time.Second):
		t.Fatal("caret speech missing")
	}
}