package config

import (
	"encoding/json"
	"errors"
	"os"
	"path/filepath"
	"strconv"
	"strings"
)

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

	AIEnabled          bool    `json:"ai_enabled"`
	AIProvider         string  `json:"ai_provider"`
	AIModel            string  `json:"ai_model"`
	AITemperature      float64 `json:"ai_temperature"`
	AISystemPromptFile string  `json:"ai_system_prompt_file"`
	AIBaseURL          string  `json:"ai_base_url"`
	AIAPIKey           string  `json:"ai_api_key"`
	AITimeoutSec       int     `json:"ai_timeout_sec"`
}

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

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",

		AIEnabled:          false,
		AIProvider:         "ollama",
		AIModel:            "llama3.2:3b",
		AITemperature:      0.0,
		AISystemPromptFile: "",
		AIBaseURL:          "http://localhost:11434",
		AIAPIKey:           "",
		AITimeoutSec:       20,
	}
}

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

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

	if _, err := os.Stat(path); err == nil {
		data, err := os.ReadFile(path)
		if err != nil {
			return cfg, err
		}
		if err := json.Unmarshal(data, &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
	}
	if v := os.Getenv("LEL_AI_ENABLED"); v != "" {
		cfg.AIEnabled = parseBool(v)
	}
	if v := os.Getenv("LEL_AI_PROVIDER"); v != "" {
		cfg.AIProvider = v
	}
	if v := os.Getenv("LEL_AI_MODEL"); v != "" {
		cfg.AIModel = v
	}
	if v := os.Getenv("LEL_AI_TEMPERATURE"); v != "" {
		if n, err := strconv.ParseFloat(v, 64); err == nil {
			cfg.AITemperature = n
		}
	}
	if v := os.Getenv("LEL_AI_SYSTEM_PROMPT_FILE"); v != "" {
		cfg.AISystemPromptFile = v
	}
	if v := os.Getenv("LEL_AI_BASE_URL"); v != "" {
		cfg.AIBaseURL = v
	}
	if v := os.Getenv("LEL_AI_API_KEY"); v != "" {
		cfg.AIAPIKey = v
	}
	if v := os.Getenv("LEL_AI_TIMEOUT_SEC"); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			cfg.AITimeoutSec = n
		}
	}
}

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