feat(location): agent to create locations

backend/models/locations.go

@@ -7,6 +7,7 @@ import (
 	. "screenmark/screenmark/.gen/haystack/haystack/table"
 
 	. "github.com/go-jet/jet/v2/postgres"
+	"github.com/go-jet/jet/v2/qrm"
 
 	"github.com/google/uuid"
 )
@@ -51,13 +52,32 @@ func (m LocationModel) Save(ctx context.Context, userId uuid.UUID, location mode
 }
 
 func (m LocationModel) SaveToImage(ctx context.Context, imageId uuid.UUID, locationId uuid.UUID) (model.ImageLocations, error) {
+	imageLocation := model.ImageLocations{}
+
+	checkExistingStmt := ImageLocations.
+		SELECT(ImageLocations.AllColumns).
+		WHERE(
+			ImageLocations.ImageID.EQ(UUID(imageId)).
+				AND(ImageLocations.LocationID.EQ(UUID(locationId))),
+		)
+
+	err := checkExistingStmt.QueryContext(ctx, m.dbPool, &imageLocation)
+	if err != nil && err != qrm.ErrNoRows {
+		// A real error
+		return model.ImageLocations{}, err
+	}
+
+	if err == nil {
+		// Already exists.
+		return imageLocation, nil
+	}
+
 	insertImageLocationStmt := ImageLocations.
 		INSERT(ImageLocations.ImageID, ImageLocations.LocationID).
 		VALUES(imageId, locationId).
 		RETURNING(ImageLocations.AllColumns)
 
-	imageLocation := model.ImageLocations{}
-	err := insertImageLocationStmt.QueryContext(ctx, m.dbPool, &imageLocation)
+	err = insertImageLocationStmt.QueryContext(ctx, m.dbPool, &imageLocation)
 
 	return imageLocation, err
 }