package config

import (
	"fmt"
	"os"
	"strconv"

	"github.com/joho/godotenv"
)

type Config struct {
	BotToken       string
	AppID          string
	GuildID        string
	DBHost         string
	LavalinkHost   string
	LavalinkPass   string
	TwitchClientID string
	OllamaHost     string
	TLDRModel      string
	TLDRThreads    int
}

func LoadConfig() (*Config, error) {
	// Load .env if present (e.g. local dev). Ignore if missing (e.g. Docker injects env vars).
	_ = godotenv.Load()

	token := os.Getenv("BOT_TOKEN")
	if token == "" {
		return nil, fmt.Errorf("BOT_TOKEN is not set")
	}

	appID := os.Getenv("APP_ID")
	if appID == "" {
		return nil, fmt.Errorf("APP_ID is not set")
	}

	guildID := os.Getenv("GUILD_ID")

	dbHost := os.Getenv("DB_HOST")
	if dbHost == "" {
		return nil, fmt.Errorf("DB_HOST is not set")
	}

	lavalinkHost := os.Getenv("LAVALINK_HOST")
	lavalinkPass := os.Getenv("LAVALINK_PASSWORD")

	twitchClientID := os.Getenv("TWITCH_CLIENT_ID")
	if twitchClientID == "" {
		return nil, fmt.Errorf("TWITCH_CLIENT_ID is not set")
	}

	ollamaHost := os.Getenv("OLLAMA_HOST")
	if ollamaHost == "" {
		ollamaHost = "http://ollama:11434"
	}
	tldrModel := os.Getenv("TLDR_MODEL")
	if tldrModel == "" {
		tldrModel = "qwen3:4b-instruct-2507-q4_K_M"
	}

	// CPU threads the summarizer may use. Keep it well under the machine's
	// core count so music playback never has to compete with inference.
	tldrThreads := 6
	if v := os.Getenv("TLDR_THREADS"); v != "" {
		n, err := strconv.Atoi(v)
		if err != nil || n < 1 {
			return nil, fmt.Errorf("TLDR_THREADS must be a positive integer, got %q", v)
		}
		tldrThreads = n
	}

	return &Config{
		BotToken:       token,
		AppID:          appID,
		GuildID:        guildID,
		DBHost:         dbHost,
		LavalinkHost:   lavalinkHost,
		LavalinkPass:   lavalinkPass,
		TwitchClientID: twitchClientID,
		OllamaHost:     ollamaHost,
		TLDRModel:      tldrModel,
		TLDRThreads:    tldrThreads,
	}, nil
}