How we wrote Telegram ChatBot to keep track of co-working spends

I guess, everyone know knows what are chat bots. Do do I, I was looking for some idea of chat bots for many months and finally, I ended up with an idea for my co-working, which I made with my friends and where I am currently spending most of my life. During the month, we collect a list of expenses, then sum them up, divide by the number of people working in the office and then, finally, reach to every individual and ask to pay for general expenses. We were tracking expenses in the Google Spreadsheet and it was working fine, in general. However, I noticed that in most of the cases, people are too lazy to go into the spreadsheet and put their expenses there. So my obsession of being up to date with modern technologies and a tiny small problem with office expenses met together, I invested 3-4 hours of my time on writing a chat bot and now we are using it. I decided to stick with Telegram, a messenger which became very popular within the last years. I used Java as a programming language. Telegram has an API for chat bots, so I made a research...