From 1856286fc23ec4332b7ccc46d9838fbb96fd4ce0 Mon Sep 17 00:00:00 2001
From: Andrew Gerrand <adg@golang.org>
Date: Thu, 4 Jul 2013 14:24:21 +1000
Subject: [PATCH] doc: update playground.js

R=dsymonds
CC=golang-dev
https://golang.org/cl/10933044
---
 doc/play/playground.js | 650 +++++++++++++++++++++++++----------------
 doc/style.css          |   5 +-
 2 files changed, 395 insertions(+), 260 deletions(-)

diff --git a/doc/play/playground.js b/doc/play/playground.js
index 709136627b..849015d1db 100644
--- a/doc/play/playground.js
+++ b/doc/play/playground.js
@@ -2,295 +2,427 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// 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)
-function playground(opts) {
-	var code = $(opts['codeEl']);
-
-	// 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);
-	}
+// This is a copy of present/js/playground.js from the repository at
+// https://code.google.com/p/go.talks
+// Please make changes to that repository.
 
-	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 output = $(opts['outputEl']);
+/*
+In the absence of any formal way to specify interfaces in JavaScript,
+here's a skeleton implementation of a playground transport.
 
-	function body() {
-		return $(opts['codeEl']).val();
-	}
-	function setBody(text) {
-		$(opts['codeEl']).val(text);
-	}
-	function origin(href) {
-		return (""+href).split("/").slice(0, 3).join("/");
-	}
-	function loading() {
-		output.removeClass("error").html(
-			'<div class="loading">Waiting for remote server...</div>'
-		);
-	}
-	var playbackTimeout;
-	function playback(pre, events) {
-		function show(msg) {
-			// ^L clears the screen.
-			var msgs = msg.split("\x0c");
-			if (msgs.length == 1) {
-				pre.text(pre.text() + msg);
-				return;
-			}
-			pre.text(msgs.pop());
-		}
+        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) {
-				var exit = $('<span class="exit"/>');
-				exit.text("\nProgram exited.");
-				exit.appendTo(pre);
+			if (events.length === 0) {
+				output({Kind: 'end'});
 				return;
 			}
 			var e = events.shift();
-			if (e.Delay == 0) {
-				show(e.Message);
+			if (e.Delay === 0) {
+				output({Kind: 'stdout', Body: e.Message});
 				next();
-			} else {
-				playbackTimeout = setTimeout(function() {
-					show(e.Message);
-					next();
-				}, e.Delay / 1000000);
+				return;
 			}
+			timeout = setTimeout(function() {
+				output({Kind: 'stdout', Body: e.Message});
+				next();
+			}, e.Delay / 1000000);
 		}
 		next();
-	}
-	function stopPlayback() {
-		clearTimeout(playbackTimeout);
-	}
-	function setOutput(events, error) {
-		stopPlayback();
-		output.empty();
-		$(".lineerror").removeClass("lineerror");
-
-		// Display errors.
-		if (error) {
-			output.addClass("error");
-			var regex = /prog.go:([0-9]+)/g;
-			var r;
-			while (r = regex.exec(error)) {
-				$(".lines div").eq(r[1]-1).addClass("lineerror");
+		return {
+			Stop: function() {
+				clearTimeout(timeout);
 			}
-			$("<pre/>").text(error).appendTo(output);
-			return;
 		}
+	}
 
-		// Display image output.
-		if (events.length > 0 && events[0].Message.indexOf("IMAGE:") == 0) {
-			var out = "";
-			for (var i = 0; i < events.length; i++) {
-				out += events[i].Message;
-			}
-			var url = "data:image/png;base64," + out.substr(6);
-			$("<img/>").attr("src", url).appendTo(output);
-			return;
-		}
+	function error(output, msg) {
+		output({Kind: 'start'});
+		output({Kind: 'stderr', Body: msg});
+		output({Kind: 'end'});
+	}
 
-		// Play back events.
-		if (events !== null) {
-			var pre = $("<pre/>").appendTo(output);
-			playback(pre, events);
+	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');
 	}
 
-	var pushedEmpty = (window.location.pathname == "/");
-	function inputChanged() {
-		if (pushedEmpty) {
+	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;
 		}
-		pushedEmpty = true;
+		output({Kind: m.Kind, Body: m.Body});
+	}
 
-		$(opts['shareURLEl']).hide();
-		window.history.pushState(null, "", "/");
+	function send(m) {
+		websocket.send(JSON.stringify(m));
 	}
 
-	function popState(e) {
-		if (e == null) {
-			return;
+	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';
 
-		if (e && e.state && e.state.code) {
-			setBody(e.state.code);
+	return function(write) {
+		if (write.Kind == 'start') {
+			el.innerHTML = '';
+			return;
 		}
-	}
 
-	var rewriteHistory = false;
+		var cl = 'system';
+		if (write.Kind == 'stdout' || write.Kind == 'stderr')
+			cl = write.Kind;
 
-	if (window.history &&
-		window.history.pushState &&
-		window.addEventListener &&
-		opts['enableHistory']) {
-		rewriteHistory = true;
-		code[0].addEventListener('input', inputChanged);
-		window.addEventListener('popstate', popState)
-	}
+		var m = write.Body;
+		if (write.Kind == 'end') 
+			m = '\nProgram exited' + (m?(': '+m):'.');
 
-	var seq = 0;
-	function run() {
-		loading();
-		seq++;
-		var cur = seq;
-		var data = {
-			"version": 2,
-			"body": body()
-		};
-		$.ajax("/compile", {
-			data: data,
-			type: "POST",
-			dataType: "json",
-			success: function(data) {
-				if (seq != cur) {
-					return;
-				}
-				if (!data) {
-					return;
-				}
-				if (data.Errors) {
-					setOutput(null, data.Errors);
-					return;
-				}
-				setOutput(data.Events, false);
-			},
-			error: function() {
-				output.addClass("error").text(
-					"Error communicating with remote server."
-				);
-			}
-		});
-	}
-	$(opts['runEl']).click(run);
-
-	$(opts['fmtEl']).click(function() {
-		loading();
-		$.ajax("/fmt", {
-			data: {"body": body()},
-			type: "POST",
-			dataType: "json",
-			success: function(data) {
-				if (data.Error) {
-					setOutput(null, data.Error);
-					return;
-				}
-				setBody(data.Body);
-				setOutput(null);
-			}
-		});
-	});
+		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;
+		}
 
-	if (opts['shareEl'] != null && (opts['shareURLEl'] != null || opts['shareRedirect'] != null)) {
-		var shareURL;
-		if (opts['shareURLEl']) {
-			shareURL = $(opts['shareURLEl']).hide();
+		// ^L clears the screen.
+		var s = m.split('\x0c');
+		if (s.length > 1) {
+			el.innerHTML = '';
+			m = s.pop();
 		}
-		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);
-				}
-			});
-		});
+		m = m.replace(/&/g, '&amp;');
+		m = m.replace(/</g, '&lt;');
+		m = m.replace(/>/g, '&gt;');
+
+		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;
+})();
diff --git a/doc/style.css b/doc/style.css
index ca8006b8dc..37b0e32c22 100644
--- a/doc/style.css
+++ b/doc/style.css
@@ -497,7 +497,10 @@ div.play .buttons a {
 	padding: 10px;
 	cursor: pointer;
 }
-div.play .output .exit {
+.output .stderr {
+	color: #933;
+}
+.output .system {
 	color: #999;
 }
 
-- 
2.48.1