package config

import (
	"encoding/json"
	"os"
	"voicesnap/internal/logger"
	"voicesnap/internal/model"
	"voicesnap/internal/paths"
)

const (
	HotkeyModeTap            = "tap"
	HotkeyModeHold           = "hold"
	LanguageModeAuto         = "auto"
	LanguageModeManual       = "manual"
	ModelSelectionModeAuto   = "auto"
	ModelSelectionModeManual = "manual"
)

// Config holds the application configuration, compatible with the WPF version's config.json.
type Config struct {
	HotkeyVK                 int    `json:"HotkeyVK"`
	HotkeyMode               string `json:"HotkeyMode"`
	AutoHide                 bool   `json:"AutoHide"`
	SoundFeedback            bool   `json:"SoundFeedback"`
	HideDockIcon             bool   `json:"HideDockIcon"`
	CopyToClipboard          bool   `json:"CopyToClipboard"`
	DeviceName               string `json:"DeviceName,omitempty"`
	IndicatorX               int    `json:"IndicatorX,omitempty"`
	IndicatorY               int    `json:"IndicatorY,omitempty"`
	SelectedModelID          string `json:"SelectedModelID,omitempty"`
	ModelSelectionMode       string `json:"ModelSelectionMode,omitempty"`
	LanguageMode             string `json:"LanguageMode,omitempty"`
	LanguageID               string `json:"LanguageID,omitempty"`
	ModelDownloadUrl         string `json:"ModelDownloadUrl"`
	FallbackModelDownloadUrl string `json:"FallbackModelDownloadUrl"`
}

// Default returns a default configuration.
func Default() *Config {
	return &Config{
		HotkeyVK:                 0xA5, // Right Alt
		HotkeyMode:               HotkeyModeHold,
		AutoHide:                 true,
		SoundFeedback:            true,
		HideDockIcon:             true,
		CopyToClipboard:          true,
		SelectedModelID:          model.DefaultModelID,
		ModelSelectionMode:       ModelSelectionModeAuto,
		LanguageMode:             LanguageModeAuto,
		LanguageID:               model.DefaultLanguageID,
		ModelDownloadUrl:         "http://www.maikami.com/voicesnap/sensevoice.zip",
		FallbackModelDownloadUrl: "https://modelscope.cn/models/sherpa-onnx/sherpa-onnx-sense-voice-zh-en-ja-ko-yue/resolve/master/sherpa-onnx-sense-voice-zh-en-ja-ko-yue-int8-2024-07-17.tar.bz2",
	}
}

func configPath() string {
	return paths.File("config.json")
}

// Load reads the config from disk. Returns default config on error.
func Load() (*Config, error) {
	path := configPath()
	data, err := os.ReadFile(path)
	if err != nil {
		if os.IsNotExist(err) {
			cfg := Default()
			Save(cfg)
			return cfg, nil
		}
		return nil, err
	}

	cfg := Default()
	if err := json.Unmarshal(data, cfg); err != nil {
		return nil, err
	}
	cfg.HotkeyMode = NormalizeHotkeyMode(cfg.HotkeyMode)
	cfg.LanguageMode = NormalizeLanguageMode(cfg.LanguageMode)
	cfg.ModelSelectionMode = NormalizeModelSelectionMode(cfg.ModelSelectionMode)
	languageID := cfg.LanguageID
	cfg.LanguageID = model.NormalizeLanguageID(cfg.LanguageID)
	if languageID != "" && languageID != cfg.LanguageID {
		logger.Info("Unknown LanguageID %q, falling back to %q", languageID, cfg.LanguageID)
	}
	selectedModelID := cfg.SelectedModelID
	cfg.SelectedModelID = model.NormalizeModelID(cfg.SelectedModelID)
	if selectedModelID != "" && selectedModelID != cfg.SelectedModelID {
		logger.Info("Unknown SelectedModelID %q, falling back to %q", selectedModelID, cfg.SelectedModelID)
	}
	return cfg, nil
}

func NormalizeLanguageMode(mode string) string {
	switch mode {
	case LanguageModeAuto, LanguageModeManual:
		return mode
	default:
		return LanguageModeAuto
	}
}

func NormalizeModelSelectionMode(mode string) string {
	switch mode {
	case ModelSelectionModeAuto, ModelSelectionModeManual:
		return mode
	default:
		return ModelSelectionModeAuto
	}
}

func NormalizeHotkeyMode(mode string) string {
	switch mode {
	case HotkeyModeTap, HotkeyModeHold:
		return mode
	default:
		return HotkeyModeHold
	}
}

// Save writes the config to disk.
func Save(cfg *Config) {
	if err := paths.Ensure(); err != nil {
		logger.Error("Failed to create app data dir: %v", err)
		return
	}

	data, err := json.MarshalIndent(cfg, "", "  ")
	if err != nil {
		logger.Error("Failed to marshal config: %v", err)
		return
	}
	if err := os.WriteFile(configPath(), data, 0644); err != nil {
		logger.Error("Failed to save config: %v", err)
	}
}