Drag and drop,Script drag and drop

Hi. I have a question about the script. The idea is that the script is responsible for moving objects with the mouse (drag and drop) and connecting them. I created the code below, which is responsible for the above functionality. I also added to it the function of rotating objects by clicking the mouse. The script is working correctly. I would like to add to it a function that would take care of linking the moved objects with each other. I was thinking about moving objects by fixed values (jumping) in two dimensions like on a grid. Please help me. I was looking for similar functionality on the network, but I could not find anything. Below is a script