index.js

import express from "express";
import request from "request";
import rp from "request-promise";
import bodyParser from "body-parser";
import {art_data} from "./data/art_data";
import {faq_helpers} from "./data/faq_helpers";
import {card_questions, card_answers} from "./data/card_questions";
import {visit} from "./data/visit_questions";
import {updateQuestion1, updateQuestion2, updateInstagram, getInstagram} from "./mongoMethod";
import {getReply} from "./data/common_words_helpers";
import https from "https";
import moment from "moment";
import Chance from "chance";
var chance = new Chance();


// start express
var app = express();
app.use(bodyParser.urlencoded({extended: false}));
app.use(bodyParser.json());
app.listen((process.env.PORT || 5000));

// set up global variables here 
var cardNumber = 0; // variable to keep track of card number

setInterval(function () {
  rp({
    url: "https://www.instagram.com/explore/tags/CenturyofLight",
    qs: { "__a": 1 },
    method: "GET"
  }).then(function (res) {
    var media = JSON.parse(res)["graphql"]["hashtag"]["edge_hashtag_to_media"]["edges"];
    var list = [];
    for (var i = 0; i < 10; i ++) {
      var item = {
        display_src: media[i]["node"]["display_url"],
        code: media[i]["node"]["shortcode"],
        caption: media[i]["node"]["edge_media_to_caption"]["edges"][0]["node"]["text"],
        owner_id: media[i]["node"]["id"],
      };
      list.push(item);
    };
    list.sort(function (a, b) {
      var id_a = a.display_src.replace("https://instagram.fsin3-1.fna.fbcdn.net/t51.2885-15/e35/","");
      var id_b = b.display_src.replace("https://instagram.fsin3-1.fna.fbcdn.net/t51.2885-15/e35/","");

      id_a = parseInt(id_a.substring(0, 8));
      id_b = parseInt(id_b.substring(0, 8));

      return id_b - id_a;
    });
    
    console.log("Updated Instagram.");
    updateInstagram(list);

  }).catch(function (err) {
    console.log("ERROR AT INSTA PROCESSER: " + err);
  });
}, 10 * 60 * 1000);


// Server index page
app.get("/", function (req, res) {
  res.send("Hello");
});

// Facebook Webhook
// Used for verification
app.get("/webhook", function (req, res) {
  if (req.query["hub.verify_token"] === process.env.VERIFICATION_TOKEN) {
    console.log("Verified webhook");
    res.status(200).send(req.query["hub.challenge"]);
  } else {
    console.error("Verification failed. The tokens do not match.");
    res.sendStatus(403);
  }
});

// All callbacks for Messenger will be POST-ed here
app.post("/webhook", function (req, res) {
  let body = req.body;

  // Make sure this is a page subscription
  if (body.object === "page") {
    // Iterate over each entry
    // There may be multiple entries if batched
    body.entry.forEach(function(entry) {
      if (entry.messaging) {
        // Gets the message. entry.messaging is an array, but 
        // will only ever contain one message, so we get index 0
        let webhookEvent = entry.messaging[0];

        if (webhookEvent.postback) {
          processPostback(webhookEvent);
        } 
        else if (webhookEvent.message) {
          processMessage(webhookEvent);
        }
      }
    });
    res.sendStatus(200);
  } else {
    // Returns a '404 Not Found' if event is not from a page subscription
    res.sendStatus(404);
  }
});

function processPostback(event) {
  let senderId = event.sender.id;
  let payload = event.postback.payload;

  if (payload === "Greeting") {
    // Get user's first name from the User Profile API
    // and include it in the greeting
    request({
      url: "https://graph.facebook.com/v2.6/" + senderId,
      qs: {
        access_token: process.env.PAGE_ACCESS_TOKEN,
        fields: "first_name"
      },
      method: "GET"
    }, function(error, response, body) {
      let greeting = "";
      if (error) {
        console.log("Error getting user's name: " +  error);
      } else {
        let bodyObj = JSON.parse(body);
        let name = bodyObj.first_name;
        startSurvey(senderId);
        sendMessage(senderId, generateWelcomeMessage(name));
      }
    });
  }
  else {
    let schema = JSON.parse(payload);

    if (schema.category == "art_data") {
      sendMessage(senderId, art_data[schema.branch]);
    }
    else if (schema.category == "instagram_impressions") {
      // INSTAGRAM API integration here
      processInsta(senderId);
    }
    else if (schema.category == "visit") {
      sendMessage(senderId, visit[schema.branch]);
    }
  }
}

function processMessage(event) {
  var message = event.message;
  var senderId = event.sender.id;

  // You may get a text or attachment but not both
  if (message.quick_reply) {
    let schema = JSON.parse(message.quick_reply.payload);

    if (schema.category == "restart") {
      sendMessage(senderId, [{
        text: "Would you like to learn about artworks, discover what other people have posted on Instagram, or find out about ticketing and opening hours to prepare for your visit? Tap one of the options below.",
        quick_replies: [
          {
            content_type:"text",
            title: "🎨 Art",
            payload: JSON.stringify({
              category: "art_data",
              branch: "ART_START"
            }),
          },
          {
            content_type:"text",
            title: "📷 #CenturyofLight",
            payload: JSON.stringify({
              category: "instagram_impressions",
              branch: "instagram_impressions"
            }),
          },
          {
            content_type:"text",
            title: "🖼 Visit",
            payload: JSON.stringify({
              category: "visit",
              branch: "visit_start"
            }),
          }
        ]
      }])
    }

    else if (schema.category == "art_data") {
      sendMessage(senderId, art_data[schema.branch]);
    }

    else if (schema.category == "pick_a_card") {
      if (schema.branch == "pick_a_card_start") {
        console.log("card number: " + cardNumber);
        sendMessage(senderId, [card_questions[cardNumber]]);
        cardNumber += 1;
        if (cardNumber > 9) {
          cardNumber = cardNumber % 10;
        }
      }
      else {
        let answer = card_answers[schema.branch];
        answer["quick_replies"] = [
          {
            content_type: "text",
            title: "🎨 Back to highlights",
            payload: JSON.stringify({
              category: "art_data",
              branch: "ART_START"
            }),
          },
          {
            content_type: "text",
            title: "👀 Next question",
            payload: JSON.stringify({
              category: "pick_a_card",
              branch: "pick_a_card_start"
            }),
          },
          {
            content_type: "text",
            title: "🎧 Audio guide",
            payload: JSON.stringify({
              category: "faq_helpers",
              branch: "AUDIO_GUIDE"
            }),          
          },
          {
            content_type: "text",
            title: "🙋 Tours",
            payload: JSON.stringify({
              category: "faq_helpers",
              branch: "NEXT_TOUR"
            }),
          }
        ];
        sendMessage(senderId, [answer], 3000);
      }           
    }

    else if (schema.category == "instagram_impressions") {
      processInsta(senderId);
    }

    else if (schema.category == "visit") {
      if (schema.branch == "visit_tickets") {
        sendMessage(senderId, visit[schema.branch])
      }
      else if (schema.branch == "visit_opening_hours"){
        let timeNow = new moment().add(8,'hours');
        sendMessage(senderId, [
          {
            text: getOpeningHourMessage(timeNow),
          },
          {
            text: "Colours of Impressionism opens from 10am to 7pm from Saturday to Thursday, and 10am to 9pm on Friday. This exhibition ends 11 March 2018.",
            quick_replies: [
              {
                content_type: "text",
                title: "🎟 Tickets",
                payload: JSON.stringify({
                  category: "visit",
                  branch: "visit_tickets"
                }),     
              },
              {
                content_type: "text",
                title: "🙋 Tours",
                payload: JSON.stringify({
                  category: "faq_helpers",
                  branch: "NEXT_TOUR",
                  entry_point: "visit"
                }),
              },
              {
                content_type: "text",
                title: "🎨 Back to highlights",
                payload: JSON.stringify({
                  category: "art_data",
                  branch: "ART_START"
                }),
              },
              {
                content_type:"text",
                title: "📷 #CenturyofLight",
                payload: JSON.stringify({
                  category: "instagram_impressions",
                  branch: "instagram_impressions"
                }),
              }
            ]
          },
        ]);
      }
      else {
        sendMessage(senderId, visit[schema.branch]);
      }
    }

    else if (schema.category == "faq_helpers") {
      let messages;
      if (schema.branch == "NEXT_TOUR") {
        
        let timeNow = new moment().add(8,'hours'); // offset the timezone difference on server and SG
        if (timeNow.hours() < 14) {
          messages = faq_helpers["NEXT_TOUR_AVAILABLE_1"];
        }
        else if (timeNow.hours() >= 14 && timeNow.hours() < 16) {
          messages = faq_helpers["NEXT_TOUR_AVAILABLE_2"];
        }
        else {
          messages = faq_helpers["NEXT_TOUR_UNAVAILABLE"];
        }
        if (schema.entry_point == "visit") {
          messages[messages.length-1]["quick_replies"] = [
            {
              content_type: "text",
              title: "🕰 Opening hours",
              payload: JSON.stringify({
                category: "visit",
                branch: "visit_opening_hours"
              }),
            },
            {
              content_type: "text",
              title: "🎟 Tickets",
              payload: JSON.stringify({
                category: "visit",
                branch: "visit_tickets"
              }),     
            },
            {
              content_type: "text",
              title: "🎨 Back to highlights",
              payload: JSON.stringify({
                category: "art_data",
                branch: "ART_START"
              }),
            },
            {
              content_type:"text",
              title: "📷 #CenturyofLight",
              payload: JSON.stringify({
                category: "instagram_impressions",
                branch: "instagram_impressions"
              }),
            }
          ];
        }
        else {
          messages[messages.length-1]["quick_replies"] = [
            {
              content_type: "text",
              title: "🎨 Back to highlights",
              payload: JSON.stringify({
                category: "art_data",
                branch: "ART_START"
              }),
            },
            {
              content_type: "text",
              title: "👀 Art of seeing art",
              payload: JSON.stringify({
                category: "pick_a_card",
                branch: "pick_a_card_start"
              }),
            },
            {
              content_type: "text",
              title: "🎧 Audio guide",
              payload: JSON.stringify({
                category: "faq_helpers",
                branch: "AUDIO_GUIDE"
              }),          
            },
          ];
        }
      }
      else {
        messages = faq_helpers[schema.branch];
        messages[messages.length-1]["quick_replies"] = [
          {
            content_type: "text",
            title: "🎨 Back to highlights",
            payload: JSON.stringify({
              category: "art_data",
              branch: "ART_START"
            }),
          },
          {
            content_type: "text",
            title: "👀 Art of seeing art",
            payload: JSON.stringify({
              category: "pick_a_card",
              branch: "pick_a_card_start"
            }),
          },
          {
            content_type: "text",
            title: "🙋 Tours",
            payload: JSON.stringify({
              category: "faq_helpers",
              branch: "NEXT_TOUR"
            }),          
          },
        ];
      }
      sendMessage(senderId, messages);
    }          

    else if (schema.category == "survey") {
      if (schema.branch == "question_1") {
        updateQuestion1(schema.choice);
        sendMessage(senderId, [{
          text: "Which feature would be most useful to you?",
          quick_replies: [
            {
              content_type: "text",
              title: "Artwork information",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "artwork_information"
              }),
            },
            {
              content_type: "text",
              title: "Things to see and do",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "things_to_see_and_do"
              }),
            },
            {
              content_type: "text",
              title: "Buy tickets",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "buy_tickets"
              }),
            },
            {
              content_type: "text",
              title: "Get directions",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "get_directions"
              }),
            },
            {
              content_type: "text",
              title: "Register for events",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "register_for_events"
              }),
            },
            {
              content_type: "text",
              title: "Promos",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "promos"
              }),
            },     
            {
              content_type: "text",
              title: "Games",
              payload: JSON.stringify({
                category: "survey",
                branch: "question_2",
                choice: "games"
              }),
            },              
          ]
        }]);
      }
      else if (schema.branch == "question_2") {
        updateQuestion2(schema.choice);
        sendMessage(senderId, [
          {
            text: "Thank you for your feedback! ☺️"
          },
          {
            text: "Shall we continue with the fun stuff?",
            quick_replies: [
              {
                content_type:"text",
                title: "🎨 Art",
                payload: JSON.stringify({
                  category: "art_data",
                  branch: "ART_START"
                }),
              },
              {
                content_type:"text",
                title: "📷 #CenturyofLight",
                payload: JSON.stringify({
                  category: "instagram_impressions",
                  branch: "instagram_impressions"
                }),
              },
              {
                content_type:"text",
                title: "🖼 Visit",
                payload: JSON.stringify({
                  category: "visit",
                  branch: "visit_tickets"
                }),
              },
            ]
          }
        ]);
      }
    }
  }

  else if (message.text) {
  	// If user were to restart the conversation
    let prompts = ["hello","hi","yo","what up","hey","hey there","get started"];
    let potentialStart = message.text.toLowerCase().replace(/[?.,\/#!$%\^&\*;:{}=\-_`~()]/g,"");
    if (prompts.indexOf(potentialStart) != -1) {
      // Get user's first name from the User Profile API
      // and include it in the greeting
      request({
        url: "https://graph.facebook.com/v2.6/" + senderId,
        qs: {
          access_token: process.env.PAGE_ACCESS_TOKEN,
          fields: "first_name"
        },
        method: "GET"
      }, function(error, response, body) {
        let greeting = "";
        if (error) {
          console.log("Error getting user's name: " +  error);
        } else {
          let bodyObj = JSON.parse(body);
          let name = bodyObj.first_name;
          sendMessage(senderId, generateWelcomeMessage(name));
        }
      });            
    }
    else {
      let sentence = message.text.toLowerCase().replace(/[?.,\/#!$%\^&\*;:{}=\-_`~()]/g,"").split(" ");
      sendMessage(senderId, getReply(sentence));
    }
    
  } else if (message.attachments) {
      sendMessage(senderId, getUnhandledRequest());
  }
}

// sends messages to user
const wait = time => new Promise((resolve) => setTimeout(resolve, time));

var sendMessage = (recipientId, messages, delay=1500, index=0) => {
  if (messages === undefined || !messages) {
    return;
  }
  if (index < messages.length) {
    var option1 = {
      url: "https://graph.facebook.com/v2.6/me/messages",
      qs: {access_token: process.env.PAGE_ACCESS_TOKEN},
      method: "POST",
      json: {
        recipient: {id: recipientId},
        sender_action: "typing_on" // typing display
      }
    };

    var option2 = {
      url: "https://graph.facebook.com/v2.6/me/messages",
      qs: {access_token: process.env.PAGE_ACCESS_TOKEN},
      method: "POST",
      json: {
        recipient: {id: recipientId},
        sender_action: "typing_off" // typing display
      }
    };

    var option3 = {
      url: "https://graph.facebook.com/v2.6/me/messages",
      qs: {access_token: process.env.PAGE_ACCESS_TOKEN},
      method: "POST",
      json: {
        recipient: {id: recipientId},
        message: messages[index],
      }
    }

    rp(option1) // rp stands for the request-promise package
      .then(res => {
        // expect response from Facebook notifying success
      })
      .then(() => {
        // wait for a few seconds to simulate typing
        return wait(delay);
      })
      .then(() => {
        // send message
        return rp(option2);
      })
      .then(() => {
        return rp(option3);
      })
      .then((res) => {
        // expect response from Facebook notifying success
        sendMessage(recipientId,messages,delay,index+1); // send next message
      })
      .catch(err => {
        console.log("error: " + JSON.stringify(err.error));
      })  
  }
  else {
    return;
  }  
}


const generateWelcomeMessage = (name) => {
  let messages = [];
  messages.push({
    text: "Hi " + name + "! Welcome to National Gallery Singapore! I'm your virtual guide 🤖 to Colours of Impressionism: Masterpieces from the Musée d'Orsay. \
This exhibition is part of Century of Light, a showcase of art from the 19th century that brings together two exhibitions — Between Worlds and Colours of Impressionism."
  });
  messages.push({
    text: "Would you like to learn about artworks, discover what other people have posted on Instagram, or find out about ticketing and opening hours to prepare for your visit? Tap one of the options below.",
    quick_replies: [
      {
        content_type:"text",
        title: "🎨 Art",
        payload: JSON.stringify({
          category: "art_data",
          branch: "ART_START"
        }),
      },
      {
        content_type:"text",
        title: "📷 #CenturyofLight",
        payload: JSON.stringify({
          category: "instagram_impressions",
          branch: "instagram_impressions"
        }),
      },
      {
        content_type:"text",
        title: "🖼 Visit",
        payload: JSON.stringify({
          category: "visit",
          branch: "visit_start"
        }),
      }
    ]
  });  
  return messages;
}

/*
  Message to be returned in the case of un-programmed input from user
*/
const getUnhandledRequest = () => {
  let message = [
    {
      text: "Please don’t play these games with my heart."
    },
    {
      text: "Can you try one of these?",
      quick_replies: [
        {
          content_type:"text",
          title: "🎨 Art",
          payload: JSON.stringify({
            category: "art_data",
            branch: "ART_START"
          }),
        },
        {
          content_type:"text",
          title: "📷 #CenturyofLight",
          payload: JSON.stringify({
            category: "instagram_impressions",
            branch: "instagram_impressions"
          }),
        },
        {
          content_type:"text",
          title: "🖼 Visit",
          payload: JSON.stringify({
            category: "visit",
            branch: "visit_start"
          }),
        }
      ]
    }
  ];
  return message;
}

/*
  Returns the relevant opening hour message
*/
const getOpeningHourMessage = (timeNow) => {
  let closingHour = (timeNow.day() == 5 ) ? 21 : 19;
  let openingHour = 10;
  let hourNow = timeNow.hour();
  let text = [];

  if (hourNow < openingHour || hourNow >= closingHour) {
    let timeToOpening = (hourNow < openingHour) ? (openingHour - hourNow) : (10 + (24-hourNow));
    text = "Oh no! We're closed for the day, " + timeToOpening + " more hours to opening.";
  }  

  else {
    if (closingHour - hourNow < 2) {
      text = "We’re closing soon at " + (closingHour-12) +  "pm!";
    }
    else {
      let hoursLeft = closingHour - hourNow;
      text = hoursLeft + " more hours of art before we close for the day!";
    }
  }

  return text;
}

const startSurvey = (senderId) => {
  setTimeout(() => {
    sendMessage(senderId, [{
      text: "Thanks for chatting with me. What would you like to see more of me in the future? ☺️",
      quick_replies: [
        {
          content_type: "text",
          title: "✔️ Yes",
          payload: JSON.stringify({
            category: "survey",
            branch: "question_1",
            choice: "yes"
          }),
        },
        {
          content_type: "text",
          title: "❌ No",
          payload: JSON.stringify({
            category: "survey",
            branch: "question_1",
            choice: "no"
          }),
        }
      ]
    }]);
  }, 15*60*1000); // to be changed for production  
}

const processInsta = (senderId) => {
  getInstagram().then(doc => {
    let list = doc.item;
    let messages = [{text: "Here are the most recent Instagram posts on Between Worlds and Colours of Impressionism, two exhibitions that are part of the Century of Light series. Tag your posts with #CenturyofLight to see your photos here!"}];
    let carouselItems = [];
    for (let i=0;i<10;i++) {
      let obj = {
        image_url: list[i].display_src,
        title: list[i].caption,
        default_action: {
          type: "web_url",
          url: "https://www.instagram.com/p/" + list[i].code + "/",
        }
      };
      carouselItems.push(obj);
    }
    let carousel = {
      attachment: {
        type: "template",
        payload: {
          template_type: "generic",
          image_aspect_ratio: "square",
          elements: carouselItems
        }
      }
    }
    messages.push(carousel);
    messages.push({
      text: "Looking for something else? Choose another option below.",
      quick_replies: [
        {
          content_type:"text",
          title: "🎨 Art",
          payload: JSON.stringify({
            category: "art_data",
            branch: "ART_START"
          }),
        },
        {
          content_type:"text",
          title: "📷 #CenturyofLight",
          payload: JSON.stringify({
            category: "instagram_impressions",
            branch: "instagram_impressions"
          }),
        },
        {
          content_type:"text",
          title: "🖼 Visit",
          payload: JSON.stringify({
            category: "visit",
            branch: "visit_start"
          }),
        }
      ]
    });  
    sendMessage(senderId, messages);    
  })
}