package config

import (
	"fmt"
	"os"
	"regexp"
	"strings"
	"time"

	"github.com/spf13/viper"
)

var MyConfig *Config

type Config struct {
	Nats         NatsConfig
	Subscription SubscriptionConfig
	Publisher    PublisherConfig
	Timeouts     TimeoutsConfig
	Hasura       HasuraConfig
}

type NatsConfig struct {
	Client  string
	URL     string
	Cluster string
}

type SubscriptionConfig struct {
	Topic      string `mapstructure:"topic"`
	QueueGroup string `mapstructure:"queue_group"`
}

type PublisherConfig struct {
	Topic string `mapstructure:"topic"`
}

type TimeoutsConfig struct {
	Server        time.Duration `mapstructure:"server"`
	ReconnectWait time.Duration `mapstructure:"reconnect_wait"`
	Close         time.Duration `mapstructure:"close"`
	AckWait       time.Duration `mapstructure:"ack_wait"`
}

type BodyConfig struct {
	Patterns []PatternConfig
}

type PatternConfig struct {
	Pattern    string
	Comments   string
	Expression *regexp.Regexp
}

type HasuraConfig struct {
	Endpoint string
	Secret   string
}

const (
	EnvProd = "prod"
	EnvDev  = "dev"
	EnvTest = "test"
)

func SetMyConfig(cfg *Config) {
	MyConfig = cfg
}

func GetMyConfig() *Config {
	if MyConfig == nil {
		cfg, err := LoadConfig()
		if err != nil {
			fmt.Printf("error loading config: %v", err)
		}
		MyConfig = cfg
	}
	return MyConfig
}

// LoadConfig loads the configuration from a file
func LoadConfig() (*Config, error) {
	// log := utils.Logger
	env := os.Getenv("GO_ENV")
	if env == "" {
		env = "dev"
	}
	// log.Infof("Environment: %s", env)

	viper.SetConfigType("toml")
	viper.SetConfigName("config." + env)
	viper.AddConfigPath("configs")
	viper.SetEnvPrefix("tele")
	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))

	if err := viper.ReadInConfig(); err != nil {
		errMsg := fmt.Sprintf("error reading config file for environment '%s': %v", env, err)
		// log.Error(errMsg)
		return nil, fmt.Errorf(errMsg)
	}

	var config Config
	if err := viper.Unmarshal(&config); err != nil {
		errMsg := fmt.Sprintf("unable to decode config into struct for environment '%s': %v", env, err)
		// log.Error(errMsg)
		return nil, fmt.Errorf(errMsg)
	}
	return &config, nil
}

// ValidateConfig validates the loaded configuration
func ValidateConfig(cfg *Config) error {
	// log := utils.Logger

	if cfg.Nats.Client == "" {
		return fmt.Errorf("nats client is required")
	}
	if cfg.Nats.URL == "" {
		return fmt.Errorf("nats URL is required")
	}
	if cfg.Subscription.Topic == "" {
		return fmt.Errorf("subscription topic is required")
	}
	// fmt.Println("config validation passed")
	return nil
}