package config

import (
	"log"
	"os"
	"strconv"

	"github.com/joho/godotenv"
)

type Config struct {
	ServerPort    string
	JWTSecret     string
	JWTExpiryHrs  int
	DatabaseURL   string
	ArtefactDir   string
	MaxConcurrent int
	BandwidthBPS  int
	RateLimitRPS  int
}

func Load() *Config {
	// Load .env file if present (silently ignore if not found)
	if err := godotenv.Load(); err != nil {
		log.Println("[config] No .env file found, using system environment variables")
	}

	return &Config{
		ServerPort:    envOrDefault("SERVER_PORT", "8080"),
		JWTSecret:     envOrDefault("JWT_SECRET", "change-me-in-production"),
		JWTExpiryHrs:  envOrDefaultInt("JWT_EXPIRY_HRS", 24),
		DatabaseURL:   envOrDefault("DATABASE_URL", "postgres://postgres:postgres@localhost:5432/manifest?sslmode=disable"),
		ArtefactDir:   envOrDefault("ARTEFACT_DIR", "/var/ota/artefacts"),
		MaxConcurrent: envOrDefaultInt("MAX_CONCURRENT_DOWNLOADS", 50),
		BandwidthBPS:  envOrDefaultInt("BANDWIDTH_BPS", 10*1024*1024/50),
		RateLimitRPS:  envOrDefaultInt("RATE_LIMIT_RPS", 100),
	}
}

func envOrDefault(key, def string) string {
	if v := os.Getenv(key); v != "" {
		return v
	}
	return def
}

func envOrDefaultInt(key string, def int) int {
	if v := os.Getenv(key); v != "" {
		if n, err := strconv.Atoi(v); err == nil {
			return n
		}
	}
	return def
}