// codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/internal/interface/http/auth/register.go
package auth

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

	"go.uber.org/zap"

	svc_auth "codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/internal/service/auth"
	"codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/pkg/httperror"
	"codeberg.org/mapleopentech/monorepo/cloud/maplefile-backend/pkg/validation"
)

// RegisterHandler handles user registration
type RegisterHandler struct {
	logger  *zap.Logger
	service svc_auth.RegisterService
}

// NewRegisterHandler creates a new registration handler
func NewRegisterHandler(
	logger *zap.Logger,
	service svc_auth.RegisterService,
) *RegisterHandler {
	return &RegisterHandler{
		logger:  logger.Named("RegisterHandler"),
		service: service,
	}
}

// ServeHTTP handles the HTTP request
func (h *RegisterHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()

	// Extract request ID from existing middleware
	requestID := httperror.ExtractRequestID(r)

	// Decode request
	var req svc_auth.RegisterRequestDTO
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		h.logger.Error("Failed to decode register request", zap.Error(err))
		problem := httperror.NewBadRequestError("Invalid request payload: " + err.Error())
		problem.WithInstance(r.URL.Path).WithTraceID(requestID)
		httperror.RespondWithProblem(w, problem)
		return
	}

	// Call service - service handles validation and returns RFC 9457 errors
	resp, err := h.service.Execute(ctx, &req)
	if err != nil {
		// Check if error is already a ProblemDetail
		if problem, ok := err.(*httperror.ProblemDetail); ok {
			h.logger.Warn("Registration failed with validation errors",
				zap.String("email", validation.MaskEmail(req.Email)),
				zap.Int("error_count", len(problem.Errors)))
			problem.WithInstance(r.URL.Path).WithTraceID(requestID)
			httperror.RespondWithProblem(w, problem)
			return
		}

		// Unexpected error - wrap in internal server error
		h.logger.Error("Registration failed with unexpected error",
			zap.String("email", validation.MaskEmail(req.Email)),
			zap.Error(err))
		problem := httperror.NewInternalServerError("Registration failed: " + err.Error())
		problem.WithInstance(r.URL.Path).WithTraceID(requestID)
		httperror.RespondWithProblem(w, problem)
		return
	}

	// Return success response
	h.logger.Info("User registered successfully", zap.String("user_id", resp.UserID))
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusCreated)
	json.NewEncoder(w).Encode(resp)
}