package env

import (
	. "ersteller-lib"
	"fmt"
	"os"
	"path/filepath"

	"github.com/joho/godotenv"
)

const (
	EnvKeyDatabaseURL          = "DATABASE_URL"
	EnvKeySessionSecret        = "SESSION_SECRET"
	EnvKeyBaseURL              = "BASE_URL"
	EnvKeyIsLocal              = "IS_LOCAL"
	EnvKeyIsDev                = "IS_DEV"
	EnvKeyGoogleClientID       = "GOOGLE_CLIENT_ID"
	EnvKeyGoogleClientSecret   = "GOOGLE_CLIENT_SECRET"
	EnvKeyGoogleRedirectURL    = "GOOGLE_REDIRECT_URL"
	EnvKeyKeycloakDiscoveryURL = "KEYCLOAK_DISCOVERY_URL"
	EnvKeyKeycloakClientID     = "KEYCLOAK_CLIENT_ID"
	EnvKeyKeycloakClientSecret = "KEYCLOAK_CLIENT_SECRET"
)

type UrlApiKey struct {
	Url    string
	ApiKey string
}

type Environment struct {
	DatabaseUrl           string
	MistralApiKey         string
	IsDev                 bool
	GoogleSheetsCredPath  string
	GoogleSheetsSpreadId  string
	GoogleSheetsSheetName string
	GoogleClientId        string
	GoogleClientSecret    string
	GoogleRedirectUrl     string
	IsLocal               bool
	SessionSecret         string
	ApifyKey              string
	Keycloak              KeycloakConfig
	BaseUrl               string
}

type KeycloakConfig struct {
	DiscoveryUrl string
	CLientId     string
	ClientSecret string
}

func LoadEnvironment() Environment {
	if _, err := os.Stat(".env"); err != nil {
		err = GenerateEnvFile("", false)
		if err != nil {
			Error("error generating the environment file", err)
		}
	}
	err := godotenv.Load()
	if err != nil {
		LogError("Error loading .env file: %v", err)
		panic(err)
	}

	return Environment{
		DatabaseUrl:        os.Getenv(EnvKeyDatabaseURL),
		IsDev:              os.Getenv(EnvKeyIsDev) == "true" || os.Getenv(EnvKeyIsLocal) == "true",
		GoogleClientId:     os.Getenv(EnvKeyGoogleClientID),
		GoogleClientSecret: os.Getenv(EnvKeyGoogleClientSecret),
		GoogleRedirectUrl:  os.Getenv(EnvKeyGoogleRedirectURL),
		IsLocal:            os.Getenv(EnvKeyIsLocal) == "true",
		SessionSecret:      os.Getenv(EnvKeySessionSecret),
		BaseUrl:            os.Getenv(EnvKeyBaseURL),
		Keycloak: KeycloakConfig{
			DiscoveryUrl: os.Getenv(EnvKeyKeycloakDiscoveryURL),
			CLientId:     os.Getenv(EnvKeyKeycloakClientID),
			ClientSecret: os.Getenv(EnvKeyKeycloakClientSecret),
		},
	}
}

// EnvKeys returns all environment variable names used by the application configuration.
// This allows other packages (e.g., CLI tools) to discover the required keys
// without duplicating or hard-coding the list elsewhere.
func EnvKeys() []string {
	return []string{
		EnvKeyDatabaseURL,
		EnvKeySessionSecret,
		EnvKeyBaseURL,
		EnvKeyIsLocal,
		EnvKeyIsDev,
		EnvKeyGoogleClientID,
		EnvKeyGoogleClientSecret,
		EnvKeyGoogleRedirectURL,
		EnvKeyKeycloakDiscoveryURL,
		EnvKeyKeycloakClientID,
		EnvKeyKeycloakClientSecret,
	}
}

// GenerateEnvFile creates a .env file template with all required environment variables
// from the EnvKeys function. The file will contain comments and default values where appropriate.
func GenerateEnvFile(rootPath string, overwrite bool) error {
	envPath := filepath.Join(rootPath, ".env")
	Debug("envPath:", envPath)
	if !overwrite {
		if _, err := os.Stat(envPath); err == nil {
			fmt.Println(".env already exists at:", envPath)
			fmt.Println("No changes made. Delete or move the existing .env to regenerate.")
			return fmt.Errorf(".env already exists at: %s", envPath)
		}
	}
	file, err := os.Create(envPath)
	if err != nil {
		return fmt.Errorf("failed to create .env file: %w", err)
	}
	defer file.Close()

	// Write header comment
	_, err = file.WriteString("# Environment Variables Configuration\n")
	if err != nil {
		return fmt.Errorf("failed to write to .env file: %w", err)
	}
	_, err = file.WriteString("# Generated from EnvKeys function\n\n")
	if err != nil {
		return fmt.Errorf("failed to write to .env file: %w", err)
	}

	// Get all environment keys
	keys := EnvKeys()

	// Define default values and comments for specific keys
	defaults := map[string]string{
		EnvKeyDatabaseURL: "\"db/starter.db?_fk=1\"",
		EnvKeyBaseURL:     "\"http://localhost:8090\"",
		EnvKeyIsLocal:     "true",
		EnvKeyIsDev:       "true",
	}

	comments := map[string]string{
		EnvKeyDatabaseURL:          "# Database connection URL",
		EnvKeySessionSecret:        "# Secret key for session management",
		EnvKeyBaseURL:              "# Base URL of the application",
		EnvKeyIsLocal:              "# Set to true for local development",
		EnvKeyIsDev:                "# Set to true for development mode",
		EnvKeyGoogleClientID:       "# Google OAuth client ID",
		EnvKeyGoogleClientSecret:   "# Google OAuth client secret",
		EnvKeyGoogleRedirectURL:    "# Google OAuth redirect URL",
		EnvKeyKeycloakDiscoveryURL: "# Keycloak discovery URL",
		EnvKeyKeycloakClientID:     "# Keycloak client ID",
		EnvKeyKeycloakClientSecret: "# Keycloak client secret",
	}

	// Write each environment variable
	for _, key := range keys {
		// Write comment if available
		if comment, exists := comments[key]; exists {
			_, err = file.WriteString(comment + "\n")
			if err != nil {
				return fmt.Errorf("failed to write to .env file: %w", err)
			}
		}

		// Write the environment variable with default value if available
		if defaultValue, exists := defaults[key]; exists {
			_, err = file.WriteString(fmt.Sprintf("%s=%s\n", key, defaultValue))
		} else {
			_, err = file.WriteString(fmt.Sprintf("%s=\n", key))
		}
		if err != nil {
			return fmt.Errorf("failed to write to .env file: %w", err)
		}
	}

	return nil
}