My Personal Expense Tracker Bot

Code.gs

// Format in Google Sheet

// Budget	10000		
// Total Expense	1100		
// Balance	8900		
			
// Date	Item	Price	
// 30/05/2021 14:30:37	Test	100	
// 30/05/2021 14:30:43	New	1000	

var token = "<bot_token_from_botfather>";
var telegramUrl = "https://api.telegram.org/bot" + token;
var webAppUrl = "<web_app_url_after_Google_app_script_deployment>";

function setWebhook() {
    var url = telegramUrl + "/setWebhook?url=" + webAppUrl;
    var response = UrlFetchApp.fetch(url);
}

function sendText(chatId, text, keyBoard) {
    var data = {
        method: "post",
        payload: {
            method: "sendMessage",
            chat_id: String(chatId),
            text: text,
            parse_mode: "HTML",
            reply_markup: JSON.stringify(keyBoard)
        }
    };
    UrlFetchApp.fetch('https://api.telegram.org/bot' + token + '/', data);
}

function isAuthorizedUser(contents) {
    var validUsers = ["<username>"];

    var username = false;

    if (contents.message) {
        var user = contents.message.from.username;
        if (!validUsers.includes(user)) {
            console.log(contents);
            sendText(contents.message.from.id, "Hi " + user + ", this is a personal bot. You are not authorized to use this. You will be reported.");
            sendText("<admin_chat_id>", "Unauthorized: " + JSON.stringify(contents.message));
        } else {
            username = user;
        }
    } else if (contents.callback_query) {
        username = contents.callback_query.from.username;
    }
    console.log(username);
    return username;
}

function doPost(e) {
    var contents = JSON.parse(e.postData.contents);

    var username = isAuthorizedUser(contents);
    if (!username) {
        return;
    }

    //set spreadsheet 
    var ssId = '<spreadsheet_id>';

    var currentDate = new Date();
    var currentMonthForSheetName = Utilities.formatDate(currentDate, Session.getScriptTimeZone(), "MMMM");
    var expenseSheet = SpreadsheetApp.openById(ssId).getSheetByName("[" + username + "]" + currentMonthForSheetName);

    var keyBoard = {
        "inline_keyboard": [
            [{
                "text": "Budget",
                'callback_data': 'budget'
            },
            {
                "text": "Total",
                'callback_data': 'total'
            }],
            [{
                "text": "Balance",
                'callback_data': 'balance'
            },
            {
                "text": "Expenses",
                'callback_data': 'expenses'
            }],
            [
                {
                    "text": "Delete last",
                    'callback_data': 'delete_last'
                }
            ]
        ]
    };

    if (contents.callback_query) {
        var id_callback = contents.callback_query.from.id;
        var data = contents.callback_query.data;
        if (data == 'budget') {
            var budget = expenseSheet.getRange(1, 2).getValue();
            sendText(id_callback, "Rs. " + budget + " is your allocated budget for the month.");
        } else if (data == 'total') {
            var total = expenseSheet.getRange(2, 2).getValue();
            sendText(id_callback, "Rs. " + total + " is your total spent so far.");
        } else if (data == 'balance') {
            var balance = expenseSheet.getRange(3, 2).getValue();
            sendText(id_callback, "Rs. " + balance + " is your money left.");
        } else if (data == 'expenses') {
            var expenses = [];
            var lr = expenseSheet.getDataRange().getLastRow();
            var expenseList;
            for (var i = 6; i <= lr; i++) {
                var date = expenseSheet.getRange(i, 1).getValue();
                var newDate = date.getMonth() + 1 + '/' + date.getDate();
                var item = expenseSheet.getRange(i, 2).getValue();
                var price = expenseSheet.getRange(i, 3).getValue();

                expenses.push("\n" + newDate + "  " + item + "  " + price);
                expenseList = expenses.join();
            }
            sendText(id_callback, decodeURI("Here are your expenses: %0A " + expenseList));
        }
        else if (data == 'delete_last') {
            var lastRow = expenseSheet.getLastRow();
            if (lastRow > 5.0) {
                var lastRowValues = expenseSheet.getRange(lastRow, 2, 1, 2);
                sendText(id_callback, decodeURI("Deleted: " + lastRowValues.getValues()));
                expenseSheet.deleteRow(lastRow);
            } else {
                sendText(id_callback, "No more items in the sheet.");
            }
        }
    }
    else if (contents.message) {
        var id_message = contents.message.from.id;

        var text = contents.message.text;
        var item = text.split("=");

        if (text.indexOf("=") !== -1) {
            //get date
            var nowDate = new Date();
            var date = nowDate;
            expenseSheet.appendRow([date, item[0], item[1]]);
            var balance = expenseSheet.getRange(3, 2).getValue();
            sendText(id_message, "Ok. Added to your expense sheet. Your balance is: Rs. " + balance);
        } else {
            sendText(id_message, "Hi " + username + ", you may send me your expenses with format: 'item = price'. You may also pull your expense reports:", keyBoard)
        }

    }
}