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                <div id="chat">
  <div id="infobar">
    <div id="nickname">name</div>
    <div id="viewCount"><b>users</b> 0</div>
  <div id="textOut"></div>
  <input id="textIn" type="text" onkeydown="event.keyCode == 13 && sendButton.onclick()"/>
  <input id="sendButton" type="button" value = "Send" />


                html, body, #chat { height: 100%; margin: 0; }
body,input { font: 20px sans-serif; }
#chat { display: flex; flex-flow: row wrap; }
#chat > * { margin: 5px 10px; padding: 10px; border: 1px solid #999; }
#infobar { width: 100%; }
#nickname { float: left; }
#viewCount { float: right; }
#textIn,#sendButton { flex: 1 0 0; }
#textOut { height: calc(100% - 160px); flex: 1 100%;  overflow: auto }
#textIn { flex-grow: 100 }
#sendButton { background-color: #fff; border: 2px solid #000 }
#widgets { top: 70px; right: 14px; }
#widgets #stats { display: none; }



                // Croquet Tutorial 3
// Multiuser Chat
// Croquet Studios, 2019-2021

class ChatModel extends Croquet.Model {
  init() {
    this.views = new Map();
    this.participants = 0;
    this.history = []; // { viewId, html } items
    this.lastPostTime = null;
    this.inactivity_timeout_ms = 60 * 1000 * 20; // constant
    this.subscribe(this.sessionId, "view-join", this.viewJoin);
    this.subscribe(this.sessionId, "view-exit", this.viewExit);
    this.subscribe("input", "newPost", this.newPost);
    this.subscribe("input", "reset", this.resetHistory);

  viewJoin(viewId) {
    const existing = this.views.get(viewId);
    if (!existing) {
      const nickname = this.randomName();
      this.views.set(viewId, nickname);
    this.publish("viewInfo", "refresh");  
  viewExit(viewId) {
    this.publish("viewInfo", "refresh");

  newPost(post) {
    const postingView = post.viewId;
    const nickname = this.views.get(postingView);
    const chatLine = `<b>${nickname}:</b> ${this.escape(post.text)}`;
    this.addToHistory({ viewId: postingView, html: chatLine });
    this.lastPostTime =;

    if (this.history.length > 100) this.history.shift();
    this.publish("history", "refresh");   

  resetIfInactive() {
    if (this.lastPostTime !== - this.inactivity_timeout_ms) return;
    this.resetHistory("due to inactivity");
  resetHistory(reason) {
    this.history = [{ html: `<i>chat reset ${reason}</i>` }];
    this.lastPostTime = null;
    this.publish("history", "refresh");
  escape(text) { // Clean up text to remove html formatting characters
    return text.replace("&", "&amp;").replace("<", "&lt;").replace(">", "&gt;");

  randomName() {
    const names =["Acorn", "Allspice", "Almond", "Ancho", "Anise", "Aoli", "Apple", "Apricot", "Arrowroot", "Asparagus", "Avocado", "Baklava", "Balsamic", "Banana", "Barbecue", "Bacon", "Basil", "Bay Leaf", "Bergamot", "Blackberry", "Blueberry", "Broccoli", "Buttermilk", "Cabbage", "Camphor", "Canaloupe", "Cappuccino", "Caramel", "Caraway", "Cardamom", "Catnip", "Cauliflower", "Cayenne", "Celery", "Cherry", "Chervil", "Chives", "Chipotle", "Chocolate", "Coconut", "Cookie Dough", "Chamomile", "Chicory", "Chutney", "Cilantro", "Cinnamon", "Clove", "Coriander", "Cranberry", "Croissant", "Cucumber", "Cupcake", "Cumin", "Curry", "Dandelion", "Dill", "Durian", "Earl Grey", "Eclair", "Eggplant", "Espresso", "Felafel", "Fennel", "Fig", "Garlic", "Gelato", "Gumbo", "Halvah", "Honeydew", "Hummus", "Hyssop", "Ghost Pepper", "Ginger", "Ginseng", "Grapefruit", "Habanero", "Harissa", "Hazelnut", "Horseradish", "Jalepeno", "Juniper", "Ketchup", "Key Lime", "Kiwi", "Kohlrabi", "Kumquat", "Latte", "Lavender", "Lemon Grass", "Lemon Zest", "Licorice", "Macaron", "Mango", "Maple Syrup", "Marjoram", "Marshmallow", "Matcha", "Mayonnaise", "Mint", "Mulberry", "Mustard", "Natto", "Nectarine", "Nutmeg", "Oatmeal", "Olive Oil", "Orange Peel", "Oregano", "Papaya", "Paprika", "Parsley", "Parsnip", "Peach", "Peanut Butter", "Pecan", "Pennyroyal", "Peppercorn", "Persimmon", "Pineapple", "Pistachio", "Plum", "Pomegranate", "Poppy Seed", "Pumpkin", "Quince", "Raspberry", "Ratatouille", "Rosemary", "Rosewater", "Saffron", "Sage", "Sassafras", "Sea Salt", "Sesame Seed", "Shiitake", "Sorrel", "Soy Sauce", "Spearmint", "Strawberry", "Strudel", "Sunflower Seed", "Sriracha", "Tabasco", "Tahini", "Tamarind", "Tandoori", "Tangerine", "Tarragon", "Thyme", "Tofu", "Truffle", "Tumeric", "Valerian", "Vanilla", "Vinegar", "Wasabi", "Walnut", "Watercress", "Watermelon", "Wheatgrass", "Yarrow", "Yuzu", "Zucchini"];
    return names[Math.floor(Math.random() * names.length)];


class ChatView extends Croquet.View {

  constructor(model) {
    this.model = model;
    sendButton.onclick = () => this.send();
    this.subscribe("history", "refresh", this.refreshHistory);
    this.subscribe("viewInfo", "refresh", this.refreshViewInfo);
    if (model.participants === 1 &&
      !model.history.find(item => item.viewId === this.viewId)) {
      this.publish("input", "reset", "for new participants");

  send() {
    const text = textIn.value;
    textIn.value = "";
    if (text === "/reset") {
      this.publish("input", "reset", "at user request");
    } else {
      this.publish("input", "newPost", {viewId: this.viewId, text});    
  refreshViewInfo() {
    nickname.innerHTML = "<b>Nickname:</b> " + this.model.views.get(this.viewId);
    viewCount.innerHTML = "<b>Current Participants:</b> " + this.model.participants;

  refreshHistory() {
    textOut.innerHTML = "<b>Welcome to Croquet Chat!</b><br><br>" + => item.html).join("<br>");
    textOut.scrollTop = Math.max(10000, textOut.scrollHeight);

  appId: "",
  apiKey: "1_9oolgb5b5wc5kju39lx8brrrhm82log9xvdn34uq",
  name: "unnamed",
  password: "secret",
  model: ChatModel,
  view: ChatView