update caching and server creation

local/model/config.go

@@ -3,6 +3,7 @@ package model
 import (
 	"encoding/json"
 	"fmt"
+	"os"
 	"strconv"
 	"time"
 )
@@ -106,6 +107,26 @@ type Configuration struct {
 	ConfigVersion IntString    `json:"configVersion"`
 }
 
+type SystemConfig struct {
+	ID            uint   `json:"id"`
+	Key           string `json:"key"`
+	Value         string `json:"value"`
+	DefaultValue  string `json:"defaultValue"`
+	Description   string `json:"description"`
+	DateModified  string `json:"dateModified"`
+}
+
+// Known configuration keys
+const (
+	ConfigKeySteamCMDPath = "steamcmd_path"
+	ConfigKeyNSSMPath     = "nssm_path"
+)
+
+// Cache keys
+const (
+	CacheKeySystemConfig = "system_config_%s"  // Format with config key
+)
+
 func (i *IntString) UnmarshalJSON(b []byte) error {
 	var str string
 	if err := json.Unmarshal(b, &str); err == nil {
@@ -136,4 +157,36 @@ func (i IntString) ToString() string {
 
 func (i IntString) ToInt() (int) {
 	return int(i)
+}
+
+func (c *SystemConfig) Validate() error {
+	if c.Key == "" {
+		return fmt.Errorf("key is required")
+	}
+
+	// Validate paths exist for certain config keys
+	switch c.Key {
+	case ConfigKeySteamCMDPath, ConfigKeyNSSMPath:
+		if c.Value == "" {
+			if c.DefaultValue == "" {
+				return fmt.Errorf("value or default value is required for path configuration")
+			}
+			// Use default value if value is empty
+			c.Value = c.DefaultValue
+		}
+		
+		// Check if path exists
+		if _, err := os.Stat(c.Value); os.IsNotExist(err) {
+			return fmt.Errorf("path does not exist: %s", c.Value)
+		}
+	}
+
+	return nil
+}
+
+func (c *SystemConfig) GetEffectiveValue() string {
+	if c.Value != "" {
+		return c.Value
+	}
+	return c.DefaultValue
 }