package config

import (
	"os"
	"strconv"
	"strings"
	"time"
)

const (
	defaultHost             = "127.0.0.1"
	defaultPort             = "2005"
	defaultDBPath           = "./hugs_proxy.db"
	defaultTokenTTLString   = "30d"
	defaultBusyTimeoutMilli = 5000
)

type Config struct {
	Host            string
	Port            string
	DBPath          string
	DefaultTokenTTL time.Duration
	BusyTimeoutMS   int
}

func Load() Config {
	host := getenvOrDefault("HUGS_PROXY_HOST", defaultHost)
	port := getenvOrDefault("HUGS_PROXY_PORT", defaultPort)
	dbPath := getenvOrDefault("HUGS_PROXY_DB_PATH", defaultDBPath)
	ttlRaw := getenvOrDefault("HUGS_PROXY_DEFAULT_TOKEN_TTL", defaultTokenTTLString)
	busyTimeout := getenvIntOrDefault("HUGS_PROXY_DB_BUSY_TIMEOUT_MS", defaultBusyTimeoutMilli)

	ttl, err := ParseExpiryDuration(ttlRaw)
	if err != nil {
		ttl, _ = ParseExpiryDuration(defaultTokenTTLString)
	}

	return Config{
		Host:            host,
		Port:            port,
		DBPath:          dbPath,
		DefaultTokenTTL: ttl,
		BusyTimeoutMS:   busyTimeout,
	}
}

func ParseExpiryDuration(s string) (time.Duration, error) {
	s = strings.TrimSpace(strings.ToLower(s))
	if strings.HasSuffix(s, "d") {
		daysPart := strings.TrimSuffix(s, "d")
		days, err := strconv.Atoi(daysPart)
		if err != nil {
			return 0, err
		}
		return time.Duration(days) * 24 * time.Hour, nil
	}
	return time.ParseDuration(s)
}

func getenvOrDefault(key string, fallback string) string {
	v := strings.TrimSpace(os.Getenv(key))
	if v == "" {
		return fallback
	}
	return v
}

func getenvIntOrDefault(key string, fallback int) int {
	v := strings.TrimSpace(os.Getenv(key))
	if v == "" {
		return fallback
	}
	n, err := strconv.Atoi(v)
	if err != nil {
		return fallback
	}
	return n
}