go_agent/src/code.google.com/p/go.tools/godoc/static/playground.js
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
/*
In the absence of any formal way to specify interfaces in JavaScript,
here's a skeleton implementation of a playground transport.
function Transport() {
// Set up any transport state (eg, make a websocket connnection).
return {
Run: function(body, output, options) {
// Compile and run the program 'body' with 'options'.
// Call the 'output' callback to display program output.
return {
Kill: function() {
// Kill the running program.
}
};
}
};
}
// The output callback is called multiple times, and each time it is
// passed an object of this form.
var write = {
Kind: 'string', // 'start', 'stdout', 'stderr', 'end'
Body: 'string' // content of write or end status message
}
// The first call must be of Kind 'start' with no body.
// Subsequent calls may be of Kind 'stdout' or 'stderr'
// and must have a non-null Body string.
// The final call should be of Kind 'end' with an optional
// Body string, signifying a failure ("killed", for example).
// The output callback must be of this form.
// See PlaygroundOutput (below) for an implementation.
function outputCallback(write) {
}
*/
function HTTPTransport() {
'use strict';
// TODO(adg): support stderr
function playback(output, events) {
var timeout;
output({Kind: 'start'});
function next() {
if (events.length === 0) {
output({Kind: 'end'});
return;
}
var e = events.shift();
if (e.Delay === 0) {
output({Kind: 'stdout', Body: e.Message});
next();
return;
}
timeout = setTimeout(function() {
output({Kind: 'stdout', Body: e.Message});
next();
}, e.Delay / 1000000);
}
next();
return {
Stop: function() {
clearTimeout(timeout);
}
}
}
function error(output, msg) {
output({Kind: 'start'});
output({Kind: 'stderr', Body: msg});
output({Kind: 'end'});
}
var seq = 0;
return {
Run: function(body, output, options) {
seq++;
var cur = seq;
var playing;
$.ajax('/compile', {
type: 'POST',
data: {'version': 2, 'body': body},
dataType: 'json',
success: function(data) {
if (seq != cur) return;
if (!data) return;
if (playing != null) playing.Stop();
if (data.Errors) {
error(output, data.Errors);
return;
}
playing = playback(output, data.Events);
},
error: function() {
error(output, 'Error communicating with remote server.');
}
});
return {
Kill: function() {
if (playing != null) playing.Stop();
output({Kind: 'end', Body: 'killed'});
}
};
}
};
}
function SocketTransport() {
'use strict';
var id = 0;
var outputs = {};
var started = {};
var websocket = new WebSocket('ws://' + window.location.host + '/socket');
websocket.onclose = function() {
console.log('websocket connection closed');
}
websocket.onmessage = function(e) {
var m = JSON.parse(e.data);
var output = outputs[m.Id];
if (output === null)
return;
if (!started[m.Id]) {
output({Kind: 'start'});
started[m.Id] = true;
}
output({Kind: m.Kind, Body: m.Body});
}
function send(m) {
websocket.send(JSON.stringify(m));
}
return {
Run: function(body, output, options) {
var thisID = id+'';
id++;
outputs[thisID] = output;
send({Id: thisID, Kind: 'run', Body: body, Options: options});
return {
Kill: function() {
send({Id: thisID, Kind: 'kill'});
}
};
}
};
}
function PlaygroundOutput(el) {
'use strict';
return function(write) {
if (write.Kind == 'start') {
el.innerHTML = '';
return;
}
var cl = 'system';
if (write.Kind == 'stdout' || write.Kind == 'stderr')
cl = write.Kind;
var m = write.Body;
if (write.Kind == 'end')
m = '\nProgram exited' + (m?(': '+m):'.');
if (m.indexOf('IMAGE:') === 0) {
// TODO(adg): buffer all writes before creating image
var url = 'data:image/png;base64,' + m.substr(6);
var img = document.createElement('img');
img.src = url;
el.appendChild(img);
return;
}
// ^L clears the screen.
var s = m.split('\x0c');
if (s.length > 1) {
el.innerHTML = '';
m = s.pop();
}
m = m.replace(/&/g, '&');
m = m.replace(/</g, '<');
m = m.replace(/>/g, '>');
var needScroll = (el.scrollTop + el.offsetHeight) == el.scrollHeight;
var span = document.createElement('span');
span.className = cl;
span.innerHTML = m;
el.appendChild(span);
if (needScroll)
el.scrollTop = el.scrollHeight - el.offsetHeight;
}
}
(function() {
function lineHighlight(error) {
var regex = /prog.go:([0-9]+)/g;
var r = regex.exec(error);
while (r) {
$(".lines div").eq(r[1]-1).addClass("lineerror");
r = regex.exec(error);
}
}
function highlightOutput(wrappedOutput) {
return function(write) {
if (write.Body) lineHighlight(write.Body);
wrappedOutput(write);
}
}
function lineClear() {
$(".lineerror").removeClass("lineerror");
}
// opts is an object with these keys
// codeEl - code editor element
// outputEl - program output element
// runEl - run button element
// fmtEl - fmt button element (optional)
// shareEl - share button element (optional)
// shareURLEl - share URL text input element (optional)
// shareRedirect - base URL to redirect to on share (optional)
// toysEl - toys select element (optional)
// enableHistory - enable using HTML5 history API (optional)
// transport - playground transport to use (default is HTTPTransport)
function playground(opts) {
var code = $(opts.codeEl);
var transport = opts['transport'] || new HTTPTransport();
var running;
// autoindent helpers.
function insertTabs(n) {
// find the selection start and end
var start = code[0].selectionStart;
var end = code[0].selectionEnd;
// split the textarea content into two, and insert n tabs
var v = code[0].value;
var u = v.substr(0, start);
for (var i=0; i<n; i++) {
u += "\t";
}
u += v.substr(end);
// set revised content
code[0].value = u;
// reset caret position after inserted tabs
code[0].selectionStart = start+n;
code[0].selectionEnd = start+n;
}
function autoindent(el) {
var curpos = el.selectionStart;
var tabs = 0;
while (curpos > 0) {
curpos--;
if (el.value[curpos] == "\t") {
tabs++;
} else if (tabs > 0 || el.value[curpos] == "\n") {
break;
}
}
setTimeout(function() {
insertTabs(tabs);
}, 1);
}
function keyHandler(e) {
if (e.keyCode == 9) { // tab
insertTabs(1);
e.preventDefault();
return false;
}
if (e.keyCode == 13) { // enter
if (e.shiftKey) { // +shift
run();
e.preventDefault();
return false;
} else {
autoindent(e.target);
}
}
return true;
}
code.unbind('keydown').bind('keydown', keyHandler);
var outdiv = $(opts.outputEl).empty();
var output = $('<pre/>').appendTo(outdiv);
function body() {
return $(opts.codeEl).val();
}
function setBody(text) {
$(opts.codeEl).val(text);
}
function origin(href) {
return (""+href).split("/").slice(0, 3).join("/");
}
var pushedEmpty = (window.location.pathname == "/");
function inputChanged() {
if (pushedEmpty) {
return;
}
pushedEmpty = true;
$(opts.shareURLEl).hide();
window.history.pushState(null, "", "/");
}
function popState(e) {
if (e === null) {
return;
}
if (e && e.state && e.state.code) {
setBody(e.state.code);
}
}
var rewriteHistory = false;
if (window.history && window.history.pushState && window.addEventListener && opts.enableHistory) {
rewriteHistory = true;
code[0].addEventListener('input', inputChanged);
window.addEventListener('popstate', popState);
}
function setError(error) {
if (running) running.Kill();
lineClear();
lineHighlight(error);
output.empty().addClass("error").text(error);
}
function loading() {
lineClear();
if (running) running.Kill();
output.removeClass("error").text('Waiting for remote server...');
}
function run() {
loading();
running = transport.Run(body(), highlightOutput(PlaygroundOutput(output[0])));
}
function fmt() {
loading();
$.ajax("/fmt", {
data: {"body": body()},
type: "POST",
dataType: "json",
success: function(data) {
if (data.Error) {
setError(data.Error);
} else {
setBody(data.Body);
setError("");
}
}
});
}
$(opts.runEl).click(run);
$(opts.fmtEl).click(fmt);
if (opts.shareEl !== null && (opts.shareURLEl !== null || opts.shareRedirect !== null)) {
var shareURL;
if (opts.shareURLEl) {
shareURL = $(opts.shareURLEl).hide();
}
var sharing = false;
$(opts.shareEl).click(function() {
if (sharing) return;
sharing = true;
var sharingData = body();
$.ajax("/share", {
processData: false,
data: sharingData,
type: "POST",
complete: function(xhr) {
sharing = false;
if (xhr.status != 200) {
alert("Server error; try again.");
return;
}
if (opts.shareRedirect) {
window.location = opts.shareRedirect + xhr.responseText;
}
if (shareURL) {
var path = "/p/" + xhr.responseText;
var url = origin(window.location) + path;
shareURL.show().val(url).focus().select();
if (rewriteHistory) {
var historyData = {"code": sharingData};
window.history.pushState(historyData, "", path);
pushedEmpty = false;
}
}
}
});
});
}
if (opts.toysEl !== null) {
$(opts.toysEl).bind('change', function() {
var toy = $(this).val();
$.ajax("/doc/play/"+toy, {
processData: false,
type: "GET",
complete: function(xhr) {
if (xhr.status != 200) {
alert("Server error; try again.");
return;
}
setBody(xhr.responseText);
}
});
});
}
}
window.playground = playground;
})();