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

package app

import (
	"bytes"
	"context"
	"errors"
	"log/slog"
	"strings"
	"testing"
	"time"

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

type continuousSpeaker struct {
	started chan string
	finish  chan struct{}
}

func TestReadAllSentencePartsKeepLineProgress(t *testing.T) {
	progress := 0
	parts := readAllLineParts("First sentence. Second sentence! Last words", func() { progress++ }, "sentence")
	if len(parts) != 3 || parts[0].Text != "First sentence." ||
		parts[1].Text != "Second sentence!" || parts[2].Text != "Last words" {
		t.Fatalf("sentence parts = %#v", parts)
	}
	if parts[0].Began == nil || parts[1].Began != nil || parts[2].Began != nil {
		t.Fatalf("line progress callbacks = %#v", parts)
	}
	parts[0].Began()
	if progress != 1 {
		t.Fatalf("progress = %d", progress)
	}
	line := readAllLineParts("First sentence. Second sentence!", nil, "line")
	if len(line) != 1 || line[0].Text != "First sentence. Second sentence!" {
		t.Fatalf("line part = %#v", line)
	}
}

func TestReadAllContextArrivesAtItsLine(t *testing.T) {
	speaker := &continuousSpeaker{started: make(chan string, 6), finish: make(chan struct{}, 2)}
	speaker.finish <- struct{}{}
	speaker.finish <- struct{}{}
	reading := config.DefaultSettings().Reading
	worker := newSpeechWorker(slog.New(slog.DiscardHandler), speaker)
	worker.reading = func() config.ReadingSettings { return reading }
	list := atspi.Snapshot{BusName: ":1.42", Path: "/list", Role: "list", Name: "Items"}
	request := speechRequest{ReadAll: []readAllPart{
		{Text: "Before", Context: []atspi.Snapshot{}},
		{Text: "Inside", Context: []atspi.Snapshot{list}},
	}}
	if err := worker.deliver(context.Background(), request); err != nil {
		t.Fatal(err)
	}
	for _, want := range []string{"Before", "Items list", "Inside"} {
		if got := <-speaker.started; got != want {
			t.Fatalf("spoken %q, want %q", got, want)
		}
	}
	reading.SayAllContextList = false
	worker.speechContext = nil
	speaker.finish <- struct{}{}
	if err := worker.deliver(context.Background(), speechRequest{ReadAll: []readAllPart{{Text: "Inside again", Context: []atspi.Snapshot{list}}}}); err != nil {
		t.Fatal(err)
	}
	if got := <-speaker.started; got != "Inside again" || len(speaker.started) != 0 {
		t.Fatalf("disabled list context speech = %q; queued = %d", got, len(speaker.started))
	}
}

func TestReadAllDiagnosticsIncludeOnlyDeliveredParts(t *testing.T) {
	var output bytes.Buffer
	speaker := &continuousSpeaker{started: make(chan string, 3), finish: make(chan struct{}, 1)}
	speaker.finish <- struct{}{}
	worker := newSpeechWorker(logging.New(&output, logging.Options{Level: slog.LevelDebug}), speaker)
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	request := speechRequest{Cause: "read-all", Role: "system", ReadAll: []readAllPart{
		{Text: "First line"}, {Text: "Second line", Began: cancel}, {Text: "Unread line"},
	}}
	if err := worker.deliver(ctx, request); !errors.Is(err, context.Canceled) {
		t.Fatalf("interrupted reading: %v", err)
	}
	for _, expected := range []string{`"utterance":"First line"`, `"utterance":"Second line"`, `"read_all_index":1`} {
		if !strings.Contains(output.String(), expected) {
			t.Fatalf("reading diagnostics missing %s: %s", expected, output.String())
		}
	}
	if strings.Contains(output.String(), "Unread line") {
		t.Fatalf("logged reading which never reached the backend: %s", output.String())
	}
}

func (*continuousSpeaker) Connect(context.Context) error { return nil }
func (*continuousSpeaker) Close(context.Context) error   { return nil }
func (*continuousSpeaker) Cancel(context.Context) error  { return nil }
func (speaker *continuousSpeaker) Speak(_ context.Context, text string) error {
	speaker.started <- text
	return nil
}
func (speaker *continuousSpeaker) SpeakAndWait(ctx context.Context, text string, began func()) error {
	if began != nil {
		began()
	}
	speaker.started <- text
	select {
	case <-speaker.finish:
		return nil
	case <-ctx.Done():
		return ctx.Err()
	}
}

func TestReadAllPacesSpeechAndInterruptsOnNewInputOrFocus(t *testing.T) {
	for _, cause := range []string{"key", "focus"} {
		t.Run(cause, func(t *testing.T) {
			speaker := &continuousSpeaker{started: make(chan string, 4), finish: make(chan struct{})}
			worker := newSpeechWorker(slog.New(slog.DiscardHandler), speaker)
			worker.Start(context.Background())
			defer worker.Stop(context.Background())
			ctx := worker.BeginReadAll(context.Background(), 100)
			// The initiating key can reach XRecord after command dispatch.
			if worker.InterruptForInput(input.Event{Pressed: true, Timestamp: 100}) || ctx.Err() != nil {
				t.Fatal("read all canceled by its initiating key")
			}
			progress := make(chan int, 3)
			worker.Enqueue(speechRequest{Cause: "read-all", context: ctx, ReadAll: []readAllPart{
				{Text: "First", Began: func() { progress <- 1 }},
				{Text: "Second", Began: func() { progress <- 2 }},
				{Text: "Third", Began: func() { progress <- 3 }},
			}})
			waitText := func(want string) {
				t.Helper()
				select {
				case got := <-speaker.started:
					if got != want {
						t.Fatalf("speech %q, want %q", got, want)
					}
				case <-time.After(time.Second):
					t.Fatalf("missing %q", want)
				}
			}
			waitText("First")
			if <-progress != 1 {
				t.Fatal("wrong starting position")
			}
			select {
			case <-speaker.started:
				t.Fatal("advanced before speech completed")
			default:
			}
			speaker.finish <- struct{}{}
			waitText("Second")
			if <-progress != 2 {
				t.Fatal("wrong second position")
			}
			if cause == "key" {
				if !worker.InterruptForInput(input.Event{Pressed: true, Timestamp: 101}) {
					t.Fatal("new key ignored")
				}
			}
			worker.Enqueue(speechRequest{Text: "New focus", Cause: "focus:"})
			waitText("New focus")
			if ctx.Err() == nil {
				t.Fatal("read all was not canceled")
			}
			select {
			case <-progress:
				t.Fatal("reading position advanced after interruption")
			default:
			}
		})
	}
}