package config

import (
	"os"
	"strconv"
)

// Config holds runtime configuration for the OpenGoods API server.
// Values are read from environment variables with sensible defaults so the
// server can boot in a local Docker Compose setup without extra configuration.
type Config struct {
	Addr                      string
	DatabaseURL               string
	RedisURL                  string
	AnonRateLimitPerMin       int
	AnonTotalQuota            int
	RegisteredRateLimitPerMin int
	RegisteredQuotaTotal      int
}

// Load reads configuration from the environment.
func Load() Config {
	return Config{
		Addr:                      getenv("OPENGOODS_ADDR", ":8080"),
		DatabaseURL:               getenv("OPENGOODS_DATABASE_URL", "postgres://opengoods:opengoods@localhost:5432/opengoods?sslmode=disable"),
		RedisURL:                  getenv("OPENGOODS_REDIS_URL", "redis://localhost:6379/0"),
		AnonRateLimitPerMin:       getenvInt("OPENGOODS_ANON_RATE_LIMIT_PER_MIN", 60),
		AnonTotalQuota:            getenvInt("OPENGOODS_ANON_TOTAL_QUOTA", 1000),
		RegisteredRateLimitPerMin: getenvInt("OPENGOODS_REGISTERED_RATE_LIMIT_PER_MIN", 300),
		RegisteredQuotaTotal:      getenvInt("OPENGOODS_REGISTERED_QUOTA_TOTAL", 100000),
	}
}

func getenvInt(key string, fallback int) int {
	if v, ok := os.LookupEnv(key); ok && v != "" {
		if n, err := strconv.Atoi(v); err == nil && n > 0 {
			return n
		}
	}
	return fallback
}

func getenv(key, fallback string) string {
	if v, ok := os.LookupEnv(key); ok && v != "" {
		return v
	}
	return fallback
}