package config

import (
	"bufio"
	"os"
	"strings"
)

type Config struct {
	Port             string
	Env              string
	DBHost           string
	DBPort           string
	DBName           string
	DBUser           string
	DBPass           string
	AdminAPIKey      string
	AdminPassword    string
	SessionSecret    string
	RSAPrivateKey    string
	RateLimitActivate string
	RateLimitValidate string
	LogLevel         string
}

func Load() *Config {
	loadEnvFile(".env")

	return &Config{
		Port:             getEnv("APP_PORT", "8090"),
		Env:              getEnv("APP_ENV", "development"),
		DBHost:           getEnv("DB_HOST", "localhost"),
		DBPort:           getEnv("DB_PORT", "3306"),
		DBName:           getEnv("DB_NAME", "dal_license_db"),
		DBUser:           getEnv("DB_USER", "license"),
		DBPass:           getEnv("DB_PASS", ""),
		AdminAPIKey:      getEnv("ADMIN_API_KEY", ""),
		AdminPassword:    getEnv("ADMIN_PASSWORD", "admin123"),
		SessionSecret:    getEnv("SESSION_SECRET", "change-me"),
		RSAPrivateKey:    getEnv("RSA_PRIVATE_KEY_PATH", "./crypto/private.pem"),
		RateLimitActivate: getEnv("RATE_LIMIT_ACTIVATE", "10"),
		RateLimitValidate: getEnv("RATE_LIMIT_VALIDATE", "60"),
		LogLevel:         getEnv("LOG_LEVEL", "info"),
	}
}

func (c *Config) DSN() string {
	return c.DBUser + ":" + c.DBPass + "@tcp(" + c.DBHost + ":" + c.DBPort + ")/" + c.DBName + "?parseTime=true&charset=utf8mb4&multiStatements=true"
}

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

func loadEnvFile(path string) {
	f, err := os.Open(path)
	if err != nil {
		return
	}
	defer f.Close()

	scanner := bufio.NewScanner(f)
	for scanner.Scan() {
		line := strings.TrimSpace(scanner.Text())
		if line == "" || strings.HasPrefix(line, "#") {
			continue
		}
		parts := strings.SplitN(line, "=", 2)
		if len(parts) == 2 {
			key := strings.TrimSpace(parts[0])
			val := strings.TrimSpace(parts[1])
			if os.Getenv(key) == "" {
				os.Setenv(key, val)
			}
		}
	}
}