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

import (
	"context"
	"errors"
	"git.stormux.org/storm/cthulhu/internal/config"
	"git.stormux.org/storm/cthulhu/internal/input"
	"git.stormux.org/storm/cthulhu/internal/preferences"
	"log/slog"
	"path/filepath"
	"reflect"
	"testing"
)

type bindingRecorder struct {
	values []input.BindingOverride
	calls  int
	err    error
}

func (recorder *bindingRecorder) SetKeyBindings(_ context.Context, values []input.BindingOverride) error {
	recorder.calls++
	if recorder.err != nil {
		return recorder.err
	}
	recorder.values = input.CloneBindingOverrides(values)
	return nil
}

func TestPreferencesKeyBindingsApplySaveResetAndFailure(t *testing.T) {
	settings := config.DefaultSettings()
	settings.Path = filepath.Join(t.TempDir(), "settings.toml")
	worker := newPreferencesWorker(slog.New(slog.DiscardHandler), settings, nil)
	recorder := &bindingRecorder{}
	worker.bindings = recorder
	values := preferences.FromSettings(settings)
	values.KeyBindings = []input.BindingOverride{{Layout: input.DesktopKeyboardLayout, Scope: "global", Command: input.Preferences, Keys: []string{"Cthulhu+F8"}}}
	recorder.err = errors.New("grab conflict")
	response := worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if response.Accepted || len(worker.settings.KeyBindings) != 0 {
		t.Fatal("failed update committed")
	}
	recorder.err = nil
	response = worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if !response.Accepted || !reflect.DeepEqual(values.KeyBindings, recorder.values) {
		t.Fatalf("apply: %+v", response)
	}
	loaded, err := config.Load(settings.Path)
	if err != nil || !reflect.DeepEqual(values.KeyBindings, loaded.KeyBindings) {
		t.Fatalf("save: %v", err)
	}
	calls := recorder.calls
	values.KeyBindings[0].Keys = []string{"Cthulhu+q"}
	response = worker.apply(context.Background(), preferences.Request{Values: values})
	if response.Accepted || recorder.calls != calls {
		t.Fatal("invalid bindings reached backend")
	}
	values.KeyBindings[0].Keys = []string{"Cthulhu+F9"}
	rate := 70.0
	values.Rate = &rate
	response = worker.apply(context.Background(), preferences.Request{Values: values})
	if response.Accepted || recorder.values[0].Keys[0] != "Cthulhu+F8" {
		t.Fatal("later backend failure did not restore keys")
	}
	values.Rate = nil
	values.KeyBindings = nil
	response = worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if !response.Accepted || len(recorder.values) != 0 {
		t.Fatal("reset was not applied")
	}
}

type keyboardRecorder struct {
	bindingRecorder
	layout    input.KeyboardLayout
	modifiers []string
}

func (recorder *keyboardRecorder) SetKeyboardConfiguration(ctx context.Context, layout input.KeyboardLayout, modifiers []string, overrides []input.BindingOverride) error {
	if err := recorder.SetKeyBindings(ctx, overrides); err != nil {
		return err
	}
	recorder.layout = layout
	recorder.modifiers = append([]string(nil), modifiers...)
	return nil
}

func TestPreferencesKeyboardConfigurationApplySaveRollback(t *testing.T) {
	settings := config.DefaultSettings()
	settings.Path = filepath.Join(t.TempDir(), "settings.toml")
	worker := newPreferencesWorker(slog.New(slog.DiscardHandler), settings, nil)
	recorder := &keyboardRecorder{}
	worker.bindings = recorder
	values := preferences.FromSettings(settings)
	values.KeyboardLayout = 2
	values.CthulhuModifierKeys = []string{"Caps_Lock"}
	recorder.err = errors.New("modifier grab conflict")
	response := worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if response.Accepted || worker.settings.KeyboardLayout != 1 {
		t.Fatal("failed modifier update committed")
	}
	recorder.err = nil
	response = worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if !response.Accepted || recorder.layout != input.LaptopKeyboardLayout || !reflect.DeepEqual(recorder.modifiers, values.CthulhuModifierKeys) {
		t.Fatalf("apply: %+v", response)
	}
	loaded, err := config.Load(settings.Path)
	if err != nil || loaded.KeyboardLayout != 2 || !reflect.DeepEqual(loaded.CthulhuModifierKeys, values.CthulhuModifierKeys) {
		t.Fatalf("save keyboard: %v", err)
	}
	values.KeyboardLayout = 1
	values.CthulhuModifierKeys = []string{"KP_Insert"}
	rate := 70.0
	values.Rate = &rate
	response = worker.apply(context.Background(), preferences.Request{Values: values})
	if response.Accepted || recorder.layout != input.LaptopKeyboardLayout || !reflect.DeepEqual(recorder.modifiers, []string{"Caps_Lock"}) {
		t.Fatal("later backend failure did not restore keyboard configuration")
	}
	values.Rate = nil
	values.CthulhuModifierKeys = []string{}
	response = worker.apply(context.Background(), preferences.Request{Values: values, Save: true})
	if !response.Accepted || len(recorder.modifiers) != 0 {
		t.Fatalf("all unchecked: %+v", response)
	}
	loaded, err = config.Load(settings.Path)
	if err != nil || len(loaded.CthulhuModifierKeys) != 0 {
		t.Fatalf("reload all unchecked: %v", err)
	}
}