app.js

var restify = require('restify');
var builder = require('botbuilder');
var c4game = require('./game');

require('dotenv').config({silent: true});

//=========================================================
// Bot Setup
//=========================================================

// Setup Restify Server
var server = restify.createServer();
var port = process.env.PORT || 3978;
server.listen(port, function () {
   console.log('%s listening to %s', server.name, server.url); 
});
  
// Create chat bot
var connector = new builder.ChatConnector({
    appId: process.env.MICROSOFT_APP_ID,
    appPassword: process.env.MICROSOFT_APP_PASSWORD
});
server.post('/c4bot/api/messages', connector.listen());

var bot = new builder.UniversalBot(connector);
var intents = new builder.IntentDialog();

bot.dialog('/', intents);

intents.matches(/^(new|play|start)/i, [
    function (session) {
        session.beginDialog("/new");
    }
]);
intents.matches(/^(help|how|guide)/i, [
    function (session) {
        session.beginDialog("/help");
    }
]);
intents.onDefault([
    function (session) {
        session.send("Hi there, I am c4bot, a bot that plays Connect Four game with you. Click here https://bots.botframework.com/bot?id=c4bot to find out more about me and my policies.");
        builder.Prompts.choice(session, "What would you like to do?", "New game|Help", {
            retryPrompt: "Sorry, I didn't understand that. \"New game\" or \"help\"?"
        });
    },
    function (session, results) {
        if (results.response && results.response.entity.toLowerCase() != 'help') {
            session.beginDialog('/new');
        } else {
            session.beginDialog('/help');
        }
    }
]);


bot.dialog('/help', [
    function (session) {
        session.send("I will play a Connect Four game with you.");
        var msg = new builder.Message(session)
            .text("A GIF worth a thousand words.")
            .attachments([{
                contentType: "image/gif",
                contentUrl: "https://upload.wikimedia.org/wikipedia/commons/a/ad/Connect_Four.gif"
            }]);
        session.send(msg);
        session.send("If you encounter any issue, please report it to my GitHub repo: https://github.com/kenrick95/c4bot/issues");
        session.endDialog();
    }
]);
bot.dialog('/new', [
    function (session) {
        session.send("Game started...");
        var game = new c4game.Game();
        session.userData.gameState = game.gameState;
        session.send(canvasToMessage(session, game.canvas, 0));
        session.beginDialog("/move");
    },
    function (session) {
        var wonPlayer = session.userData.gameState.wonPlayer;
        var gameEnded = session.userData.gameState.won;

        var msg = "";
        if (gameEnded) {
            msg = "It's a draw";
            if (wonPlayer > 0) {
                msg = "You won!";
            } else if (wonPlayer < 0) {
                msg = "Computer won!";
            }
            msg += "\n";
        }

        session.send();
        session.endDialog(msg + "Game over. Thank you for playing.\nSay 'hi' again to restart the game.");
    }
]);
bot.dialog('/invalid', [
    function (session) {
        session.send("Invalid move, please choose another column");
        session.replaceDialog("/move");
    }
]);

bot.dialog('/move', [
    function (session) {
        builder.Prompts.text(session, "Please choose a column (1-7)");
    },
    function (session, results) {
        if (/^(end|restart)/i.test(results.response)) {
            session.endDialog();
            return;
        }

        var choice = builder.EntityRecognizer.parseNumber(results.response) - 1;
        if (isNaN(choice) || choice < 0 || choice > 6) {
            session.replaceDialog("/invalid");
            return;
        }

        var game = new c4game.Game();
        // restore state
        game.gameState = session.userData.gameState;

        // resume game
        game.gameState.paused = false;

        // do action
        var valid = game.action(choice, function () {
            // print state (after user move)
            session.send(canvasToMessage(session, game.canvas, 1));
            session.sendBatch();

            if (!game.gameState.won) {
                this.ai.bind(this)(-1);

                // print state (after AI move)
                session.send(canvasToMessage(session, game.canvas, -1));
            }
            
        }.bind(game));

        if (valid < 1) {
            session.replaceDialog("/invalid");
            return;
        }
        
        // save state
        session.userData.gameState = game.gameState;
        
        // next move
        if (!session.userData.gameState.won) {
            session.replaceDialog("/move");
        } else {
            session.endDialog();
        }
    }
]);

function canvasToMessage(session, canvas, player) {
    return new builder.Message(session)
        .text((player != 0) ? ((player > 0) ? "You moved 🔴" : "Computer moved 🔵") : "Waiting for your move")
        .attachments([{
            contentType: "image/png",
            contentUrl: canvas.toDataURL()
        }]);
}