package api

import (
	"encoding/json"
	"net/http"

	"github.com/go-chi/chi/v5"
	"github.com/kindredsystems/silo/internal/auth"
	"github.com/kindredsystems/silo/internal/db"
)

// HandleRegisterWorkstation registers or re-registers a workstation for the current user.
func (s *Server) HandleRegisterWorkstation(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	user := auth.UserFromContext(ctx)
	if user == nil {
		writeError(w, http.StatusUnauthorized, "unauthorized", "Authentication required")
		return
	}

	var req struct {
		Name     string `json:"name"`
		Hostname string `json:"hostname"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeError(w, http.StatusBadRequest, "invalid_json", err.Error())
		return
	}
	if req.Name == "" {
		writeError(w, http.StatusBadRequest, "validation_error", "name is required")
		return
	}

	ws := &db.Workstation{
		Name:     req.Name,
		UserID:   user.ID,
		Hostname: req.Hostname,
	}
	if err := s.workstations.Upsert(ctx, ws); err != nil {
		s.logger.Error().Err(err).Str("name", req.Name).Msg("failed to register workstation")
		writeError(w, http.StatusInternalServerError, "internal_error", "Failed to register workstation")
		return
	}

	s.broker.Publish("workstation.registered", mustMarshal(map[string]any{
		"id":       ws.ID,
		"name":     ws.Name,
		"user_id":  ws.UserID,
		"hostname": ws.Hostname,
	}))

	writeJSON(w, http.StatusOK, map[string]any{
		"id":         ws.ID,
		"name":       ws.Name,
		"hostname":   ws.Hostname,
		"last_seen":  ws.LastSeen.UTC().Format("2006-01-02T15:04:05Z"),
		"created_at": ws.CreatedAt.UTC().Format("2006-01-02T15:04:05Z"),
	})
}

// HandleListWorkstations returns all workstations for the current user.
func (s *Server) HandleListWorkstations(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	user := auth.UserFromContext(ctx)
	if user == nil {
		writeError(w, http.StatusUnauthorized, "unauthorized", "Authentication required")
		return
	}

	workstations, err := s.workstations.ListByUser(ctx, user.ID)
	if err != nil {
		s.logger.Error().Err(err).Msg("failed to list workstations")
		writeError(w, http.StatusInternalServerError, "internal_error", "Failed to list workstations")
		return
	}

	type wsResponse struct {
		ID        string `json:"id"`
		Name      string `json:"name"`
		Hostname  string `json:"hostname"`
		LastSeen  string `json:"last_seen"`
		CreatedAt string `json:"created_at"`
	}

	out := make([]wsResponse, len(workstations))
	for i, ws := range workstations {
		out[i] = wsResponse{
			ID:        ws.ID,
			Name:      ws.Name,
			Hostname:  ws.Hostname,
			LastSeen:  ws.LastSeen.UTC().Format("2006-01-02T15:04:05Z"),
			CreatedAt: ws.CreatedAt.UTC().Format("2006-01-02T15:04:05Z"),
		}
	}

	writeJSON(w, http.StatusOK, out)
}

// HandleDeleteWorkstation removes a workstation owned by the current user (or any, for admins).
func (s *Server) HandleDeleteWorkstation(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	user := auth.UserFromContext(ctx)
	if user == nil {
		writeError(w, http.StatusUnauthorized, "unauthorized", "Authentication required")
		return
	}

	id := chi.URLParam(r, "id")
	ws, err := s.workstations.GetByID(ctx, id)
	if err != nil {
		s.logger.Error().Err(err).Str("id", id).Msg("failed to get workstation")
		writeError(w, http.StatusInternalServerError, "internal_error", "Failed to get workstation")
		return
	}
	if ws == nil {
		writeError(w, http.StatusNotFound, "not_found", "Workstation not found")
		return
	}

	if ws.UserID != user.ID && user.Role != auth.RoleAdmin {
		writeError(w, http.StatusForbidden, "forbidden", "You can only delete your own workstations")
		return
	}

	if err := s.workstations.Delete(ctx, id); err != nil {
		s.logger.Error().Err(err).Str("id", id).Msg("failed to delete workstation")
		writeError(w, http.StatusInternalServerError, "internal_error", "Failed to delete workstation")
		return
	}

	s.broker.Publish("workstation.removed", mustMarshal(map[string]any{
		"id":      ws.ID,
		"name":    ws.Name,
		"user_id": ws.UserID,
	}))

	w.WriteHeader(http.StatusNoContent)
}