Refactor instance status management: replace Running boolean with InstanceStatus enum and update related methods

pkg/instance/status.go

@@ -0,0 +1,72 @@
+package instance
+
+import (
+	"encoding/json"
+	"log"
+)
+
+// Enum for instance status
+type InstanceStatus int
+
+const (
+	Stopped InstanceStatus = iota
+	Running
+	Failed
+)
+
+var nameToStatus = map[string]InstanceStatus{
+	"stopped": Stopped,
+	"running": Running,
+	"failed":  Failed,
+}
+
+var statusToName = map[InstanceStatus]string{
+	Stopped: "stopped",
+	Running: "running",
+	Failed:  "failed",
+}
+
+func (p *Process) SetStatus(status InstanceStatus) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+
+	p.Status = status
+}
+
+func (p *Process) GetStatus() InstanceStatus {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	return p.Status
+}
+
+// IsRunning returns true if the status is Running
+func (p *Process) IsRunning() bool {
+	p.mu.RLock()
+	defer p.mu.RUnlock()
+	return p.Status == Running
+}
+
+func (s InstanceStatus) MarshalJSON() ([]byte, error) {
+	name, ok := statusToName[s]
+	if !ok {
+		name = "stopped" // Default to "stopped" for unknown status
+	}
+	return json.Marshal(name)
+}
+
+// UnmarshalJSON implements json.Unmarshaler
+func (s *InstanceStatus) UnmarshalJSON(data []byte) error {
+	var str string
+	if err := json.Unmarshal(data, &str); err != nil {
+		return err
+	}
+
+	status, ok := nameToStatus[str]
+	if !ok {
+		log.Printf("Unknown instance status: %s", str)
+		status = Stopped // Default to Stopped on unknown status
+	}
+
+	*s = status
+	return nil
+}