CUB-127: implement Control Center CRUD API in Go

go-backend/internal/store/agent.go

@@ -0,0 +1,177 @@
+// Package store provides thread-safe in-memory data stores for the
+// Control Center API. These will be replaced with PostgreSQL-backed
+// implementations once CUB-120 (schema design) is complete.
+package store
+
+import (
+	"sort"
+	"sync"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"github.com/google/uuid"
+)
+
+// AgentStore provides thread-safe CRUD operations for agents.
+type AgentStore struct {
+	mu      sync.RWMutex
+	agents  map[string]models.AgentCardData
+	history map[string][]models.AgentStatusHistoryEntry // agentID -> history
+}
+
+// NewAgentStore returns an initialized AgentStore.
+func NewAgentStore() *AgentStore {
+	return &AgentStore{
+		agents:  make(map[string]models.AgentCardData),
+		history: make(map[string][]models.AgentStatusHistoryEntry),
+	}
+}
+
+// List returns all agents, optionally filtered by status.
+func (s *AgentStore) List(statusFilter models.AgentStatus) []models.AgentCardData {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	result := make([]models.AgentCardData, 0, len(s.agents))
+	for _, a := range s.agents {
+		if statusFilter != "" && a.Status != statusFilter {
+			continue
+		}
+		result = append(result, a)
+	}
+
+	// Sort by display name for consistent output.
+	sort.Slice(result, func(i, j int) bool {
+		return result[i].DisplayName < result[j].DisplayName
+	})
+	return result
+}
+
+// Get returns a single agent by ID, or false if not found.
+func (s *AgentStore) Get(id string) (models.AgentCardData, bool) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	a, ok := s.agents[id]
+	return a, ok
+}
+
+// Create inserts a new agent. Returns false if the ID already exists.
+func (s *AgentStore) Create(a models.AgentCardData) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, exists := s.agents[a.ID]; exists {
+		return false
+	}
+	if a.LastActivity == "" {
+		a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	}
+	s.agents[a.ID] = a
+
+	// Record initial history entry.
+	s.appendHistoryLocked(a.ID, models.AgentStatusHistoryEntry{
+		ID:        uuid.New().String(),
+		AgentID:   a.ID,
+		Status:    a.Status,
+		Task:      a.CurrentTask,
+		Timestamp: a.LastActivity,
+	})
+	return true
+}
+
+// Update applies partial updates to an agent. Returns the updated agent or false if not found.
+func (s *AgentStore) Update(id string, req models.UpdateAgentRequest) (models.AgentCardData, bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	a, ok := s.agents[id]
+	if !ok {
+		return models.AgentCardData{}, false
+	}
+
+	prevStatus := a.Status
+	prevTask := a.CurrentTask
+
+	if req.Status != nil {
+		a.Status = *req.Status
+	}
+	if req.CurrentTask != nil {
+		a.CurrentTask = req.CurrentTask
+	}
+	if req.TaskProgress != nil {
+		a.TaskProgress = req.TaskProgress
+	}
+	if req.TaskElapsed != nil {
+		a.TaskElapsed = req.TaskElapsed
+	}
+	if req.Channel != nil {
+		a.Channel = *req.Channel
+	}
+	if req.ErrorMessage != nil {
+		a.ErrorMessage = req.ErrorMessage
+	}
+	a.LastActivity = time.Now().UTC().Format(time.RFC3339)
+	s.agents[id] = a
+
+	// Record history entry if status or task changed.
+	if (req.Status != nil && *req.Status != prevStatus) || (req.CurrentTask != nil && prevTask == nil) ||
+		(req.CurrentTask != nil && prevTask != nil && *req.CurrentTask != *prevTask) {
+		status := a.Status
+		if req.Status != nil {
+			status = *req.Status
+		}
+		s.appendHistoryLocked(id, models.AgentStatusHistoryEntry{
+			ID:        uuid.New().String(),
+			AgentID:   id,
+			Status:    status,
+			Task:      a.CurrentTask,
+			Timestamp: a.LastActivity,
+		})
+	}
+
+	return a, true
+}
+
+// Delete removes an agent. Returns true if the agent existed.
+func (s *AgentStore) Delete(id string) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, ok := s.agents[id]; !ok {
+		return false
+	}
+	delete(s.agents, id)
+	delete(s.history, id)
+	return true
+}
+
+// History returns the status history for an agent, newest first.
+func (s *AgentStore) History(agentID string) []models.AgentStatusHistoryEntry {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	entries, ok := s.history[agentID]
+	if !ok {
+		return nil
+	}
+	// Return a defensive copy, sorted newest first (by index when timestamps tie).
+	result := make([]models.AgentStatusHistoryEntry, len(entries))
+	copy(result, entries)
+	sort.SliceStable(result, func(i, j int) bool {
+		if result[i].Timestamp == result[j].Timestamp {
+			return i > j // later index = newer when timestamps match
+		}
+		return result[i].Timestamp > result[j].Timestamp
+	})
+	return result
+}
+
+// Count returns the total number of agents.
+func (s *AgentStore) Count() int {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return len(s.agents)
+}
+
+// appendHistoryLocked adds a history entry. Caller must hold s.mu (write lock).
+func (s *AgentStore) appendHistoryLocked(agentID string, entry models.AgentStatusHistoryEntry) {
+	s.history[agentID] = append(s.history[agentID], entry)
+}