app.js

'use strict';

process.env.DEBUG = 'actions-on-google:*';
let Assistant = require('actions-on-google').ApiAiAssistant;
let express = require('express');
let Fuse = require('fuse.js');
let bodyParser = require('body-parser');
let yahooFinance = require('yahoo-finance');

let app = express();
app.use(bodyParser.json({type: 'application/json'}));

const INTENT_WELCOME = "input.welcome";
const INTENT_CHECK_BALANCE = "check_balance";
const INTENT_CHECK_BILLS = "check_bills";
const INTENT_PAY_BILL = "pay_bill";
const INTENT_GET_STOCK_INFO = "get_stock_info";

const ARG_BILL_NAME = "billName";
const ARG_STOCKS = "stocks";

app.post('/', function (req, res) {
  const assistant = new Assistant({request: req, response: res});
  console.log('Request headers: ' + JSON.stringify(req.headers));
  console.log('Request body: ' + JSON.stringify(req.body));

  function init (assistant) {
    assistant.data.cashMoney = 2000;
    assistant.data.bills = [
      { recepient: "Anime Mystery Box", cost: 50.00 },
      { recepient: "University of Waterloo Tuition Bill", cost: 8000.00 },
      { recepient: "Waterloo North Hydro", cost: 120.00 }
    ];
    assistant.ask('Sup fam, Budgetbot at your service.');
  }

  function checkBalance (assistant) {
    assistant.ask("Your account balance is $" + assistant.data.cashMoney + ".");
  }

  function checkBills (assistant) {
    let billsArray = assistant.data.bills;
    var statement = "Good job, no bills are due for this month!";
    if (billsArray.length > 0) {
      statement = "The following bills are due by the end of the month: ";
      for (var i=0; i < billsArray.length; i++) {
        let bill = billsArray[i];
        statement = statement + bill["recepient"] + " at $" + bill["cost"];
        if (i == billsArray.length - 1) {
          statement = statement + ".";
        } else if (i == billsArray.length - 2) {
          statement = statement + ", and ";
        } else {
          statement = statement + ", ";
        }
      }
    }
    assistant.ask(statement);
  }

  function payBill (assistant) {
    console.log("INFO: payBill - this is being called");
    let fuzzyBillsArray = new Fuse(assistant.data.bills, { keys: ["recepient"] });
    let currentCashMoney = assistant.data.cashMoney;
    let targetBillName = assistant.getArgument(ARG_BILL_NAME);

    let fuzzyResults = fuzzyBillsArray.search(targetBillName);

    if (fuzzyResults.length > 0) {
      let foundBill = fuzzyResults[0];
      let billRecepient = foundBill["recepient"];
      let billCost = foundBill["cost"];
      if (billCost <= currentCashMoney) {
        deleteBill(foundBill);
        assistant.data.cashMoney = assistant.data.cashMoney - billCost;
        assistant.ask("Okay, paying $" + billCost + " to " + billRecepient + ". You have $" + assistant.data.cashMoney + " remaining.");
      } else {
        assistant.ask("Whoops, you don't have enough money to pay that bill. The bill is $" + billCost + ", and you have $" + currentCashMoney + " on hand.");
      }
    } else {
      assistant.ask("Sorry, I can't seem to find that bill.");
    }
  }

  function deleteBill(targetBill) {
    for (var i=0; i < assistant.data.bills.length; i++) {
      if (assistant.data.bills[i]["recepient"] === targetBill["recepient"] && assistant.data.bills[i]["cost"] === targetBill["cost"]) {
        assistant.data.bills.splice(i, 1);
        return;
      }
    }
  }

  function getStockInfo (assistant) {
    let stock = assistant.getArgument(ARG_STOCKS);
    return new Promise(function(resolve, reject) {
      yahooFinance.snapshot({
        symbol: stock,
        fields: ['n', 'l1']
      }, function (err, snapshot) {
        if (snapshot) {
          assistant.ask(snapshot["name"] + " is trading at $" + snapshot["lastTradePriceOnly"] + " per share.");
        } else {
          assistant.ask("Sorry, I can't seem to load stock data at the moment.");
          reject(Error("Unable to retrieve stock data."));
        }
      })
    });
  }

  let actionMap = new Map();
  actionMap.set(INTENT_WELCOME, init);
  actionMap.set(INTENT_CHECK_BALANCE, checkBalance);
  actionMap.set(INTENT_CHECK_BILLS, checkBills);
  actionMap.set(INTENT_PAY_BILL, payBill);
  actionMap.set(INTENT_GET_STOCK_INFO, getStockInfo);

  assistant.handleRequest(actionMap);
});

if (module === require.main) {
  let server = app.listen(process.env.PORT || 8080, function () {
    let port = server.address().port;
    console.log('App listening on port %s', port);
  });
}

module.exports = app;