//go:build linux && cgo

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

package app

import (
	"context"
	"fmt"
	"io"
	"log/slog"
	"os"
	"strings"
	"syscall"
	"testing"
	"time"
	"unsafe"

	"git.stormux.org/storm/cthulhu/internal/config"
	"git.stormux.org/storm/cthulhu/internal/preferences"
)

func test_hardware_switch(t *testing.T, speaker *configuredSpeaker, software config.Settings) {
	t.Helper()
	fd, err := syscall.Open("/dev/ptmx", syscall.O_RDWR|syscall.O_NOCTTY|syscall.O_NONBLOCK, 0600)
	if err != nil {
		t.Fatal(err)
	}
	master := os.NewFile(uintptr(fd), "hardware-speech-fixture")
	defer master.Close()
	var unlocked int32
	var number uint32
	if _, _, code := syscall.Syscall(syscall.SYS_IOCTL, uintptr(fd), syscall.TIOCSPTLCK, uintptr(unsafe.Pointer(&unlocked))); code != 0 {
		t.Fatal(code)
	}
	if _, _, code := syscall.Syscall(syscall.SYS_IOCTL, uintptr(fd), syscall.TIOCGPTN, uintptr(unsafe.Pointer(&number))); code != 0 {
		t.Fatal(code)
	}
	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
	defer cancel()
	hardware := software
	hardware.SpeechServerFactory = "hardwarefactory"
	hardware.SpeechOutputModule = "litetalk"
	hardware.HardwareSpeechDevice = fmt.Sprintf("/dev/pts/%d", number)
	hardware.HardwareSpeechBaudRate = 9600
	rate, pitch, volume := 99.0, 9.0, 9.0
	hardware.DefaultVoice = config.Voice{Rate: &rate, AveragePitch: &pitch, Gain: &volume}
	if err := speaker.UpdateConfiguration(ctx, hardware); err != nil {
		t.Fatal(err)
	}
	check := func(speak func(context.Context, string) error, text, want string) {
		t.Helper()
		if err := speak(ctx, text); err != nil {
			t.Fatal(err)
		}
		master.SetReadDeadline(time.Now().Add(time.Second))
		buffer := make([]byte, len(want))
		if _, err := io.ReadFull(master, buffer); err != nil || string(buffer) != want {
			t.Fatalf("serial=%q want=%q error=%v", buffer, want, err)
		}
	}
	check(speaker.Speak, "Default", "\x019S\x0199P\x019VDefault\r")
	check(speaker.SpeakCharacter, "A", "\x019S\x0199P\x019VA\r")
	check(speaker.SpeakCharacter, "a", "\x019S\x0199P\x019Va\r")

	worker := newPreferencesWorker(slog.New(slog.DiscardHandler), hardware, speaker)
	values := preferences.FromSettings(hardware)
	rateLow := 0.0
	values.Rate = &rateLow
	if response := worker.apply(ctx, preferences.Request{Values: values}); !response.Accepted {
		t.Fatal(response.Message)
	}
	check(speaker.Speak, "Applied", "\x18\x010S\x0199P\x019VApplied\r")
	values.HardwareSpeechDevice = "/dev/cthulhu-missing-serial-fixture"
	if response := worker.apply(ctx, preferences.Request{Values: values}); response.Accepted {
		t.Fatal("unavailable serial device accepted")
	}
	if worker.settings.HardwareSpeechDevice != hardware.HardwareSpeechDevice {
		t.Fatal("failed Apply committed a missing device")
	}
	check(speaker.Speak, "Retained", "\x010S\x0199P\x019VRetained\r")
	if err := speaker.UpdateConfiguration(ctx, software); err != nil {
		t.Fatal(err)
	}
	if !strings.HasPrefix(worker.settings.HardwareSpeechDevice, "/dev/pts/") {
		t.Fatal("unexpected fixture device")
	}
}