package config

import (
	"errors"
	"os"
	"path/filepath"
	"strconv"
	"strings"

	"github.com/BurntSushi/toml"
)

type Config struct {
	Hotkey            string `toml:"hotkey"`
	FfmpegInput       string `toml:"ffmpeg_input"`
	WhisperModel      string `toml:"whisper_model"`
	WhisperLang       string `toml:"whisper_lang"`
	WhisperDevice     string `toml:"whisper_device"`
	WhisperExtraArgs  string `toml:"whisper_extra_args"`
	RecordTimeoutSec  int    `toml:"record_timeout_sec"`
	WhisperTimeoutSec int    `toml:"whisper_timeout_sec"`
	SegmentSec        int    `toml:"segment_sec"`
	Streaming         bool   `toml:"streaming"`
	InjectionBackend  string `toml:"injection_backend"`
}

func DefaultPath() string {
	home, _ := os.UserHomeDir()
	return filepath.Join(home, ".config", "lel", "config.toml")
}

func Defaults() Config {
	return Config{
		Hotkey:            "Cmd+m",
		FfmpegInput:       "pulse:default",
		WhisperModel:      "base",
		WhisperLang:       "en",
		WhisperDevice:     "cpu",
		WhisperExtraArgs:  "",
		RecordTimeoutSec:  120,
		WhisperTimeoutSec: 300,
		SegmentSec:        5,
		Streaming:         false,
		InjectionBackend:  "clipboard",
	}
}

func Load(path string) (Config, error) {
	cfg := Defaults()

	if path == "" {
		path = DefaultPath()
	}

	if _, err := os.Stat(path); err == nil {
		if _, err := toml.DecodeFile(path, &cfg); err != nil {
			return cfg, err
		}
	}

	applyEnv(&cfg)

	if strings.TrimSpace(cfg.Hotkey) == "" {
		return cfg, errors.New("hotkey cannot be empty")
	}
	if cfg.RecordTimeoutSec <= 0 {
		return cfg, errors.New("record_timeout_sec must be > 0")
	}
	if cfg.WhisperTimeoutSec <= 0 {
		return cfg, errors.New("whisper_timeout_sec must be > 0")
	}

	return cfg, nil
}

func applyEnv(cfg *Config) {
	if v := os.Getenv("WHISPER_MODEL"); v != "" {
		cfg.WhisperModel = v
	}
	if v := os.Getenv("WHISPER_LANG"); v != "" {
		cfg.WhisperLang = v
	}
	if v := os.Getenv("WHISPER_DEVICE"); v != "" {
		cfg.WhisperDevice = v
	}
	if v := os.Getenv("WHISPER_EXTRA_ARGS"); v != "" {
		cfg.WhisperExtraArgs = v
	}
	if v := os.Getenv("WHISPER_FFMPEG_IN"); v != "" {
		cfg.FfmpegInput = v
	}
	if v := os.Getenv("WHISPER_STREAM"); v != "" {
		cfg.Streaming = parseBool(v)
	}
	if v := os.Getenv("WHISPER_SEGMENT_SEC"); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			cfg.SegmentSec = n
		}
	}
	if v := os.Getenv("WHISPER_TIMEOUT_SEC"); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			cfg.WhisperTimeoutSec = n
		}
	}
	if v := os.Getenv("LEL_RECORD_TIMEOUT_SEC"); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			cfg.RecordTimeoutSec = n
		}
	}
	if v := os.Getenv("LEL_HOTKEY"); v != "" {
		cfg.Hotkey = v
	}
	if v := os.Getenv("LEL_INJECTION_BACKEND"); v != "" {
		cfg.InjectionBackend = v
	}
}

func parseBool(v string) bool {
	v = strings.ToLower(strings.TrimSpace(v))
	return v == "1" || v == "true" || v == "yes" || v == "on"
}