refactor: move config handler to internal

internal/config/viper.go

@@ -0,0 +1,44 @@
+package config
+
+import (
+	"github.com/spf13/viper"
+	"log"
+)
+
+type AppConfig struct {
+	Port        string
+	Private     bool
+	TemplateDir string
+	LogDir      string
+	PasteDir    string
+	Expire      int // Add an expiration setting
+}
+
+func LoadConfig() (*AppConfig, error) {
+	var config AppConfig
+
+	viper.SetConfigName("config") // name of the config file (without extension)
+	viper.AddConfigPath(".")      // look in the current directory for the config file
+	viper.AutomaticEnv()          // read in environment variables that match
+
+	viper.SetDefault("Port", "8080")
+	viper.SetDefault("Private", false)
+	viper.SetDefault("TemplateDir", "templates")
+	viper.SetDefault("LogDir", "logs")
+	viper.SetDefault("PasteDir", "pastes")
+	viper.SetDefault("Expire", 24) //  in hours
+	viper.SetDefault("Metrics", false)
+
+	// read the configuration file if it's present
+	// goblin can also be configured through command lines during runtime
+	if err := viper.ReadInConfig(); err != nil {
+		log.Printf("Failed to read config file: %v\n", err)
+	}
+
+	// Unmarshal the configuration into the AppConfig struct
+	if err := viper.Unmarshal(&config); err != nil {
+		return nil, err
+	}
+
+	return &config, nil
+}