package gapi

import (
	"context"
	"errors"
	"strings"

	db "github.com/FernandoJVideira/api_tmpl/internal/db/sqlc"
	"github.com/FernandoJVideira/api_tmpl/internal/domain/role"
	"github.com/FernandoJVideira/api_tmpl/internal/service"
	"github.com/FernandoJVideira/api_tmpl/internal/val"
	"github.com/FernandoJVideira/api_tmpl/pb"
	"google.golang.org/genproto/googleapis/rpc/errdetails"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

func (s *Server) UpdateUser(ctx context.Context, req *pb.UpdateUserRequest) (*pb.UpdateUserResponse, error) {
	authPayload, err := s.authorizeUser(ctx, []string{role.AdminRole, role.MemberRole})
	if err != nil {
		return nil, unauthenticatedError(err)
	}

	if authPayload.Role != role.AdminRole && authPayload.Username != req.GetUsername() {
		return nil, status.Errorf(codes.PermissionDenied, "cannot update other user's information")
	}

	violations := validateUpdateUserRequest(req)
	if violations != nil {
		return nil, invalidArgumentError(violations)
	}

	updateReq := service.UserUpdateRequest{
		Username: req.GetUsername(),
	}
	// Set FullName if provided
	if req.FullName != nil {
		fullName := req.GetFullName()
		updateReq.FullName = &fullName
	}

	// Set Email if provided
	if req.Email != nil {
		email := req.GetEmail()
		updateReq.Email = &email
	}

	user, err := s.userService.UpdateUser(ctx, updateReq)
	if err != nil {
		if errors.Is(err, db.ErrRecordNotFound) || strings.Contains(err.Error(), "not found") {
			return nil, status.Errorf(codes.NotFound, "user not found: %v", err)
		}
		return nil, status.Errorf(codes.Internal, "failed to update user: %v", err)
	}
	resp := &pb.UpdateUserResponse{
		User: convertUser(*user),
	}
	return resp, nil
}

func validateUpdateUserRequest(req *pb.UpdateUserRequest) (violations []*errdetails.BadRequest_FieldViolation) {
	if err := val.ValidateUsername(req.GetUsername()); err != nil {
		violations = append(violations, fieldViolation("username", err))
	}

	if req.FullName != nil {
		if err := val.ValidateFullName(req.GetFullName()); err != nil {
			violations = append(violations, fieldViolation("full_name", err))
		}
	}

	if req.Password != nil {
		if err := val.ValidatePassword(req.GetPassword()); err != nil {
			violations = append(violations, fieldViolation("password", err))
		}
	}

	if req.Email != nil {
		if err := val.ValidateEmail(req.GetEmail()); err != nil {
			violations = append(violations, fieldViolation("email", err))
		}
	}
	return violations
}

func unauthenticatedError(err error) error {
	return status.Errorf(codes.Unauthenticated, "unauthenticated: %v", err)
}