veza/veza-backend-api/internal/handlers/kyc_handler.go

package handlers

import (
	"errors"
	"net/http"

	apperrors "veza-backend-api/internal/errors"
	"veza-backend-api/internal/services"
	"veza-backend-api/internal/validators"

	"github.com/gin-gonic/gin"
	"go.uber.org/zap"
)

// KYCHandler handles seller identity verification endpoints (v0.13.5 TASK-MKT-001)
type KYCHandler struct {
	kycService           *services.KYCService
	logger               *zap.Logger
	allowedRedirectHosts []string // v1.0.10 sécu item 7: open-redirect protection on return_url
}

// NewKYCHandler creates a new KYC handler. allowedRedirectHosts is
// the per-environment list of hosts that may receive the user's
// browser after KYC completes (Stripe Identity redirect).
func NewKYCHandler(kycService *services.KYCService, logger *zap.Logger, allowedRedirectHosts []string) *KYCHandler {
	return &KYCHandler{
		kycService:           kycService,
		logger:               logger,
		allowedRedirectHosts: allowedRedirectHosts,
	}
}

// CreateVerificationRequest is the request body for starting KYC
type CreateVerificationRequest struct {
	ReturnURL string `json:"return_url"`
}

// StartVerification creates a Stripe Identity verification session
// @Summary Start KYC verification
// @Description Initiate a Stripe Identity verification session for the seller.
// @Tags Sell
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param data body CreateVerificationRequest true "Return URL"
// @Success 201 {object} handlers.APIResponse{data=object}
// @Failure 401 {object} handlers.APIResponse "Unauthorized"
// @Router /api/v1/sell/kyc/start [post]
func (h *KYCHandler) StartVerification(c *gin.Context) {
	if h.kycService == nil {
		RespondWithAppError(c, apperrors.NewServiceUnavailableError("KYC verification is not available"))
		return
	}

	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}

	var req CreateVerificationRequest
	_ = c.ShouldBindJSON(&req)
	returnURL := req.ReturnURL
	if returnURL == "" {
		returnURL = c.Request.URL.Scheme + "://" + c.Request.Host + "/sell?kyc=complete"
	}

	// v1.0.10 sécu item 7 — open-redirect protection. The user submits
	// this URL and it ends up in a Stripe Identity redirect ; allow-list
	// gates the host so a phishing return_url can't be smuggled through.
	if err := validators.ValidateRedirectURL(returnURL, h.allowedRedirectHosts); err != nil {
		RespondWithAppError(c, apperrors.NewValidationError("invalid return_url: "+err.Error()))
		return
	}

	session, err := h.kycService.CreateVerificationSession(c.Request.Context(), userID, returnURL)
	if err != nil {
		if errors.Is(err, services.ErrKYCAlreadyDone) {
			RespondSuccess(c, http.StatusOK, gin.H{"status": "verified", "message": "Already verified"})
			return
		}
		if errors.Is(err, services.ErrKYCNotAvailable) {
			RespondWithAppError(c, apperrors.NewServiceUnavailableError("KYC verification is not available"))
			return
		}
		if errors.Is(err, services.ErrNoStripeAccount) {
			RespondWithAppError(c, apperrors.NewValidationError("Complete Stripe Connect onboarding first"))
			return
		}
		h.logger.Error("StartVerification failed", zap.Error(err), zap.String("user_id", userID.String()))
		RespondWithAppError(c, apperrors.NewInternalErrorWrap("Failed to start verification", err))
		return
	}

	RespondSuccess(c, http.StatusCreated, session)
}

// GetVerificationStatus returns the current KYC status for a seller
// @Summary Get KYC status
// @Description Get the current identity verification status for the authenticated seller.
// @Tags Sell
// @Accept json
// @Produce json
// @Security BearerAuth
// @Success 200 {object} handlers.APIResponse{data=object{status=string}}
// @Failure 401 {object} handlers.APIResponse "Unauthorized"
// @Router /api/v1/sell/kyc/status [get]
func (h *KYCHandler) GetVerificationStatus(c *gin.Context) {
	if h.kycService == nil {
		RespondSuccess(c, http.StatusOK, gin.H{"status": "not_available"})
		return
	}

	userID, ok := GetUserIDUUID(c)
	if !ok {
		return
	}

	status, err := h.kycService.GetVerificationStatus(c.Request.Context(), userID)
	if err != nil {
		if errors.Is(err, services.ErrKYCNotAvailable) {
			RespondSuccess(c, http.StatusOK, gin.H{"status": "not_available"})
			return
		}
		h.logger.Error("GetVerificationStatus failed", zap.Error(err), zap.String("user_id", userID.String()))
		RespondWithAppError(c, apperrors.NewInternalErrorWrap("Failed to get verification status", err))
		return
	}

	RespondSuccess(c, http.StatusOK, gin.H{"status": status})
}