Refactor instance management and add InstanceManager interface

server/pkg/manager.go

@@ -0,0 +1,156 @@
+package llamactl
+
+import (
+	"fmt"
+
+	"github.com/google/uuid"
+)
+
+// InstanceManager defines the interface for managing instances of the llama server.
+type InstanceManager interface {
+	ListInstances() ([]*Instance, error)
+	CreateInstance(options *InstanceOptions) (*Instance, error)
+	GetInstance(id uuid.UUID) (*Instance, error)
+	UpdateInstance(id uuid.UUID, options *InstanceOptions) (*Instance, error)
+	DeleteInstance(id uuid.UUID) error
+	StartInstance(id uuid.UUID) (*Instance, error)
+	StopInstance(id uuid.UUID) (*Instance, error)
+	RestartInstance(id uuid.UUID) (*Instance, error)
+	GetInstanceLogs(id uuid.UUID) (string, error)
+}
+
+type instanceManager struct {
+	instances map[uuid.UUID]*Instance
+	portRange [][2]int // Range of ports to use for instances
+	ports     map[int]bool
+}
+
+// NewInstanceManager creates a new instance of InstanceManager.
+func NewInstanceManager() InstanceManager {
+	return &instanceManager{
+		instances: make(map[uuid.UUID]*Instance),
+		portRange: [][2]int{{8000, 9000}},
+		ports:     make(map[int]bool),
+	}
+}
+
+// ListInstances returns a list of all instances managed by the instance manager.
+func (im *instanceManager) ListInstances() ([]*Instance, error) {
+	var instances []*Instance
+	for _, instance := range im.instances {
+		instances = append(instances, instance)
+	}
+	return instances, nil
+}
+
+// CreateInstance creates a new instance with the given options and returns it.
+// The instance is initially in a "stopped" state.
+func (im *instanceManager) CreateInstance(options *InstanceOptions) (*Instance, error) {
+	id := uuid.New()
+	instance := &Instance{
+		ID:      id,
+		Port:    8080,      // Default port, can be changed later
+		Status:  "stopped", // Initial status
+		Options: options,
+	}
+	im.instances[id] = instance
+	return instance, nil
+}
+
+// GetInstance retrieves an instance by its ID.
+func (im *instanceManager) GetInstance(id uuid.UUID) (*Instance, error) {
+	instance, exists := im.instances[id]
+	if !exists {
+		return nil, fmt.Errorf("instance with ID %s not found", id)
+	}
+	return instance, nil
+}
+
+// UpdateInstance updates the options of an existing instance and returns it.
+func (im *instanceManager) UpdateInstance(id uuid.UUID, options *InstanceOptions) (*Instance, error) {
+	instance, exists := im.instances[id]
+	if !exists {
+		return nil, fmt.Errorf("instance with ID %s not found", id)
+	}
+	instance.Options = options
+	return instance, nil
+}
+
+// DeleteInstance removes stopped instance by its ID.
+func (im *instanceManager) DeleteInstance(id uuid.UUID) error {
+	_, exists := im.instances[id]
+	if !exists {
+		return fmt.Errorf("instance with ID %s not found", id)
+	}
+
+	if im.instances[id].Status != "stopped" {
+		return fmt.Errorf("cannot delete a running instance, stop it first")
+	}
+
+	delete(im.instances, id)
+	return nil
+}
+
+// StartInstance starts a stopped instance and returns it.
+// If the instance is already running, it returns an error.
+func (im *instanceManager) StartInstance(id uuid.UUID) (*Instance, error) {
+	instance, exists := im.instances[id]
+	if !exists {
+		return nil, fmt.Errorf("instance with ID %s not found", id)
+	}
+	if instance.Status == "running" {
+		return instance, fmt.Errorf("instance with ID %s is already running", id)
+	}
+
+	//TODO:
+
+	instance.Status = "running"
+	return instance, nil
+}
+
+// StopInstance stops a running instance and returns it.
+func (im *instanceManager) StopInstance(id uuid.UUID) (*Instance, error) {
+	instance, exists := im.instances[id]
+	if !exists {
+		return nil, fmt.Errorf("instance with ID %s not found", id)
+	}
+	if instance.Status == "stopped" {
+		return instance, fmt.Errorf("instance with ID %s is already stopped", id)
+	}
+
+	// TODO:
+	instance.Status = "stopped"
+	return instance, nil
+}
+
+// RestartInstance stops and then starts an instance, returning the updated instance.
+func (im *instanceManager) RestartInstance(id uuid.UUID) (*Instance, error) {
+	instance, err := im.StopInstance(id)
+	if err != nil {
+		return nil, err
+	}
+	return im.StartInstance(instance.ID)
+}
+
+// GetInstanceLogs retrieves the logs for a specific instance by its ID.
+func (im *instanceManager) GetInstanceLogs(id uuid.UUID) (string, error) {
+	_, exists := im.instances[id]
+	if !exists {
+		return "", fmt.Errorf("instance with ID %s not found", id)
+	}
+
+	// TODO: Implement actual log retrieval logic
+	return fmt.Sprintf("Logs for instance %s", id), nil
+}
+
+func (im *instanceManager) getNextAvailablePort() (int, error) {
+	for _, portRange := range im.portRange {
+		for port := portRange[0]; port <= portRange[1]; port++ {
+			if !im.ports[port] {
+				im.ports[port] = true
+				return port, nil
+			}
+		}
+	}
+	return 0, fmt.Errorf("no available ports in the specified range")
+}