CUB-127: implement Control Center CRUD API in Go

go-backend/internal/handler/agent.go

@@ -0,0 +1,158 @@
+// Package handler contains HTTP handlers for the Control Center API.
+// Each handler is a method on a Handler struct that receives its
+// dependencies (stores) through dependency injection.
+package handler
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/models"
+	"code.cubecraftcreations.com/CubeCraft-Creations/Control-Center/go-backend/internal/store"
+	"github.com/go-chi/chi/v5"
+	"github.com/go-playground/validator/v10"
+)
+
+// Handler groups all route handlers and their dependencies.
+type Handler struct {
+	AgentStore   *store.AgentStore
+	SessionStore *store.SessionStore
+	TaskStore    *store.TaskStore
+	ProjectStore *store.ProjectStore
+	validate     *validator.Validate
+}
+
+// NewHandler returns a fully wired Handler.
+func NewHandler(
+	as *store.AgentStore,
+	ss *store.SessionStore,
+	ts *store.TaskStore,
+	ps *store.ProjectStore,
+) *Handler {
+	v := validator.New()
+	v.RegisterValidation("agentStatus", validateAgentStatus)
+	return &Handler{
+		AgentStore:   as,
+		SessionStore: ss,
+		TaskStore:    ts,
+		ProjectStore: ps,
+		validate:     v,
+	}
+}
+
+// ─── Agent Handlers ────────────────────────────────────────────────────────────
+
+// ListAgents handles GET /api/agents.
+func (h *Handler) ListAgents(w http.ResponseWriter, r *http.Request) {
+	statusFilter := models.AgentStatus(r.URL.Query().Get("status"))
+	allAgents := h.AgentStore.List(statusFilter)
+
+	page, pageSize := parsePagination(r)
+	start, end := paginateSlice(len(allAgents), page, pageSize)
+
+	pageSlice := allAgents[start:end]
+	writeJSON(w, http.StatusOK, models.PaginatedResponse{
+		Data:       pageSlice,
+		TotalCount: h.AgentStore.Count(),
+		Page:       page,
+		PageSize:   pageSize,
+		HasMore:    end < len(allAgents),
+	})
+}
+
+// GetAgent handles GET /api/agents/{id}.
+func (h *Handler) GetAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	agent, ok := h.AgentStore.Get(id)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// CreateAgent handles POST /api/agents.
+func (h *Handler) CreateAgent(w http.ResponseWriter, r *http.Request) {
+	var req models.CreateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent := models.AgentCardData{
+		ID:          req.ID,
+		DisplayName: req.DisplayName,
+		Role:        req.Role,
+		Status:      req.Status,
+		CurrentTask: req.CurrentTask,
+		SessionKey:  req.SessionKey,
+		Channel:     req.Channel,
+		LastActivity: time.Now().UTC().Format(time.RFC3339),
+	}
+
+	if ok := h.AgentStore.Create(agent); !ok {
+		writeJSON(w, http.StatusConflict, models.ErrorResponse{Error: "agent with this ID already exists"})
+		return
+	}
+	writeJSON(w, http.StatusCreated, agent)
+}
+
+// UpdateAgent handles PUT /api/agents/{id}.
+func (h *Handler) UpdateAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+
+	var req models.UpdateAgentRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		writeJSON(w, http.StatusBadRequest, models.ErrorResponse{Error: "invalid request body"})
+		return
+	}
+
+	if err := h.validate.Struct(req); err != nil {
+		writeJSON(w, http.StatusUnprocessableEntity, models.ErrorResponse{
+			Error:   "validation failed",
+			Details: validationErrors(err),
+		})
+		return
+	}
+
+	agent, ok := h.AgentStore.Update(id, req)
+	if !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	writeJSON(w, http.StatusOK, agent)
+}
+
+// DeleteAgent handles DELETE /api/agents/{id}.
+func (h *Handler) DeleteAgent(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if ok := h.AgentStore.Delete(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// AgentHistory handles GET /api/agents/{id}/history.
+func (h *Handler) AgentHistory(w http.ResponseWriter, r *http.Request) {
+	id := chi.URLParam(r, "id")
+	if _, ok := h.AgentStore.Get(id); !ok {
+		writeJSON(w, http.StatusNotFound, models.ErrorResponse{Error: "agent not found"})
+		return
+	}
+
+	history := h.AgentStore.History(id)
+	if history == nil {
+		history = []models.AgentStatusHistoryEntry{}
+	}
+	writeJSON(w, http.StatusOK, history)
+}