<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
-
<html xmlns="http://www.w3.org/1999/xhtml">
+<!--
+ reliable-chat - multipath chat
+ Copyright (C) 2012 Scott Worley <sworley@chkno.net>
+ Copyright (C) 2012 Jason Hibbs <skitch@gmail.com>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as
+ published by the Free Software Foundation, either version 3 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+-->
<head>
<title>Reliable Chat</title>
<style type="text/css"><!--/*--><![CDATA[/*><!--*/
padding: 0px 5px 55px 5px;
vertical-align: bottom
}
+ .timestamp {
+ margin-right: 0.8em;
+ }
img { width: 1px; height: 1px; }
iframe { display: none }
#status span { margin-right: 10px; }
<script type="text/javascript"><!--//--><![CDATA[//><!--
var servers = ['chkno.net', 'rc2.chkno.net', 'echto.net', 'the-wes.com', 'vibrantlogic.com'];
- var session = Math.random();
- var seen = {};
+ var session = Math.random(); // For outgoing message IDs
+ var since = {}; // server -> time: For fetch?since=
+ var seen = {}; // seen_key -> message
+ var history = []; // List of messages sorted by Time
+ // Messages have these fields:
+ // Time: The timestamp. Median of ServerTimes
+ // ID: Some unique string for deduping
+ // Text: The text of the message
+ // ServerTimes: server -> timestamp
+ // UI: The DOM node for this message in the UI
function rcnick() {
var nick = localStorage.getItem("nick");
}
}
+ function rcformattime(t) {
+ var d = t.getDay();
+ d = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"][d];
+ var h = t.getHours();
+ var m = t.getMinutes();
+ var s = t.getSeconds();
+ function pad(x) {
+ return (x < 10 ? "0" : "") + x;
+ }
+ return d + " " + pad(h) + ":" + pad(m) + ":" + pad(s);
+ }
+
function rcaddmessagetohistory(message) {
- var d = document.createElement("div");
- d.appendChild(document.createTextNode(message));
+ var message_i;
+ if (message.Time) {
+ for (var i = history.length - 1; ; i--) {
+ if (i < 0 || (history[i].Time && message.Time >= history[i].Time)) {
+ message_i = i+1;
+ history.splice(message_i, 0, message);
+ break;
+ }
+ }
+ } else {
+ history.push(message);
+ message_i = history.length-1;
+ }
+
+ if (!message.UI) {
+ var timestamp_text = message.Time ? rcformattime(message.Time) : "";
+ var timestamp = document.createElement("span");
+ timestamp.setAttribute("class", "timestamp");
+ timestamp.appendChild(document.createTextNode(timestamp_text));
+ message.UI = document.createElement("div");
+ message.UI.appendChild(timestamp);
+ message.UI.appendChild(document.createTextNode(message.Text));
+ }
var h = document.getElementById("history");
- h.appendChild(d);
+ if (message_i + 1 < history.length) {
+ h.insertBefore(message.UI, history[message_i + 1].UI);
+ } else {
+ h.appendChild(message.UI);
+ }
window.scrollTo(0, document.body.scrollHeight);
- return d;
}
function make_seen_key(id, text) {
return id.replace(/@/g, "@@") + "_@_" + text.replace(/@/g, "@@");
}
- function receiveMessage(server, time, id, text) {
- var seen_key = make_seen_key(id, text);
- if (!(seen_key in seen)) {
- seen[seen_key] = true;
- rcaddmessagetohistory(text);
- for (var i in servers) {
- rcchangeserverstatus(servers[i], "sad");
+ function rcupdatemessagetime(message) {
+ // Set message.Time to be the median of message.ServerTimes
+ var times = [];
+ for (var i in message.ServerTimes) {
+ times.push(message.ServerTimes[i]);
+ }
+ times.sort();
+ if (times.length % 2) {
+ message.Time = times[(times.length-1)/2];
+ } else {
+ var middle = times.length/2;
+ var difference = times[middle].getTime() - times[middle-1].getTime();
+ message.Time = new Date(times[middle-1].getTime() + difference/2);
+ }
+
+ // This may have broken history's in-sorted-order invariant
+ var hi = history.indexOf(message);
+ if ((history[hi-1] && history[hi-1].Time > message.Time) ||
+ (history[hi+1] && history[hi+1].Time < message.Time)) {
+ history.splice(hi,1);
+ rcaddmessagetohistory(message);
+ }
+ }
+
+ function rcreceivemessages(server, messages) {
+ for (var i in messages) {
+ var m = messages[i];
+ m.Time = new Date(m.Time);
+ var seen_key = make_seen_key(m.ID, m.Text);
+ if (seen_key in seen) {
+ seen[seen_key].ServerTimes[server] = m.Time;
+ rcupdatemessagetime(seen[seen_key]);
+ } else {
+ m.ServerTimes = {};
+ m.ServerTimes[server] = m.Time;
+ seen[seen_key] = m;
+ rcaddmessagetohistory(m);
+ for (var i in servers) {
+ rcchangeserverstatus(servers[i], "sad");
+ }
}
+ rcchangeserverstatus(server, "happy");
}
- rcchangeserverstatus(server, "happy");
}
- function receiveMessageEvent(event)
- {
- for (var i in servers) {
- if (event.origin === rcserverbase(servers[i])) {
- messages = JSON.parse(event.data);
- for (var j in messages) {
- if ('Time' in messages[j] &&
- 'ID' in messages[j] &&
- 'Text' in messages[j]) {
- receiveMessage(servers[i], messages[j]['Time'], messages[j]['ID'], messages[j]['Text']);
+ function rcfetch(server) {
+ var delay = 10000; // TODO: Exponential backoff
+ var xhr = new XMLHttpRequest();
+ xhr.onreadystatechange = function() {
+ if (this.readyState == this.DONE) {
+ if (this.status == 200) {
+ var rtxt = this.responseText;
+ if (rtxt != null) {
+ var messages = JSON.parse(rtxt);
+ if (messages != null) {
+ delay = 40;
+ if (messages.length >= 1 && "Time" in messages[messages.length-1]) {
+ since[server] = messages[messages.length-1].Time;
+ }
+ rcreceivemessages(server, messages);
+ }
}
}
+ window.setTimeout(rcfetch, delay, server);
}
}
+ var uri = rcserverbase(server) + "/fetch";
+ if (server in since) {
+ uri += '?since="' + since[server] + '"';
+ }
+ xhr.open("GET", uri);
+ xhr.send();
}
function rcconnect() {
- window.addEventListener("message", receiveMessageEvent, false);
for (var i in servers) {
- // Create a hidden iframe for same-origin workaround
- var iframe = document.createElement("iframe");
- iframe.setAttribute("src", rcserverbase(servers[i]) + "/frame");
- document.body.insertBefore(iframe, document.body.firstChild);
+ rcfetch(servers[i]);
// Status bar entry
var status_indicator = document.createElement("span");
status_indicator.appendChild(document.createTextNode(servers[i]));
status_indicator.setAttribute("class", "sad");
document.getElementById("status").appendChild(status_indicator);
}
- if (rcnick() == 'anonymous') {
- rcaddmessagetohistory("-!- Set your nick with /nick");
- }
}
function rcsend(d, message) {
- var id = new Date().getTime() + "-" + session + "-" + Math.random();
- seen[make_seen_key(id, message)] = true;
+ message.ID = new Date().getTime() + "-" + session + "-" + Math.random();
+ seen[make_seen_key(message.ID, message.Text)] = message;
var path = "/speak" +
- "?id=" + encodeURIComponent(id) +
- "&text=" + encodeURIComponent(message);
+ "?id=" + encodeURIComponent(message.ID) +
+ "&text=" + encodeURIComponent(message.Text);
for (var i in servers) {
var uri = rcserverbase(servers[i]) + path;
var img = document.createElement("img");
}
}
+ function rcinput(input) {
+ var message;
+ var re = /^\/([a-z]+) (.*)/
+ var match = re.exec(input);
+ if (match && match[1] == 'me') {
+ message = "* " + rcnick() + " " + match[2];
+ } else if (match && match[1] == 'nick') {
+ message = "*** " + rcnick() + " is now known as " + match[2];
+ rcsetnick(match[2]);
+ } else {
+ message = "<" + rcnick() + "> " + input;
+ }
+
+ var m = {'Text': message, 'ServerTimes': {}};
+ rcaddmessagetohistory(m);
+ rcsend(m.UI, m);
+ }
+
function rckeydown(event) {
if (event.keyCode == 13) {
- var input = document.input.say.value;
+ rcinput(document.input.say.value);
document.input.say.value = "";
- // Check nick change
- var message;
- var re = /^\/nick (.*)/;
- var match = re.exec(input);
- if (match) {
- message = "*** " + rcnick() + " is now known as " + match[1];
- rcsetnick(match[1]);
- } else {
- message = "<" + rcnick() + "> " + input;
- }
-
- // /me support
- var message;
- var re = /^\/me (.*)/;
- var match = re.exec(input);
- var inputme = input.substring(4);
- if (match) {
- message = "* " + rcnick() + " " + inputme;
- } else {
- message = "<" + rcnick() + "> " + input;
- }
-
- // Remind people to set their nick
- if (rcnick() == 'anonymous') {
- rcaddmessagetohistory("-!- Set your nick with /nick");
- }
-
- // Say the message
- var d = rcaddmessagetohistory(message);
- rcsend(d, message);
}
}
//--><!]]></script>
projects / reliable-chat / blobdiff