From d2ff164c07788818ded9826c9e3811599272e69c Mon Sep 17 00:00:00 2001
From: Jermolene <jeremy@jermolene.com>
Date: Fri, 15 Dec 2017 15:08:18 +0000
Subject: [PATCH] Add support for tm-copy-to-clipboard message

---
 core/language/en-GB/Notifications.multids     |  2 ++
 core/modules/startup/rootwidget.js            |  4 +++
 core/modules/utils/dom/dom.js                 | 30 +++++++++++++++++++
 .../WidgetMessage_ tm-copy-to-clipboard.tid   | 25 ++++++++++++++++
 4 files changed, 61 insertions(+)
 create mode 100644 editions/tw5.com/tiddlers/messages/WidgetMessage_ tm-copy-to-clipboard.tid

diff --git a/core/language/en-GB/Notifications.multids b/core/language/en-GB/Notifications.multids
index 0d9b891bd..df095b828 100644
--- a/core/language/en-GB/Notifications.multids
+++ b/core/language/en-GB/Notifications.multids
@@ -2,3 +2,5 @@ title: $:/language/Notifications/
 
 Save/Done: Saved wiki
 Save/Starting: Starting to save wiki
+CopiedToClipboard/Succeeded: Copied!
+CopiedToClipboard/Failed: Failed to copy to clipboard!
diff --git a/core/modules/startup/rootwidget.js b/core/modules/startup/rootwidget.js
index 2b5111aff..5afd2d536 100644
--- a/core/modules/startup/rootwidget.js
+++ b/core/modules/startup/rootwidget.js
@@ -30,6 +30,10 @@ exports.startup = function() {
 	$tw.rootWidget.addEventListener("tm-notify",function(event) {
 		$tw.notifier.display(event.param,{variables: event.paramObject});
 	});
+	// Install the copy-to-clipboard  mechanism
+	$tw.rootWidget.addEventListener("tm-copy-to-clipboard",function(event) {
+		$tw.utils.copyToClipboard(event.param);
+	});
 	// Install the scroller
 	$tw.pageScroller = new $tw.utils.PageScroller();
 	$tw.rootWidget.addEventListener("tm-scroll",function(event) {
diff --git a/core/modules/utils/dom/dom.js b/core/modules/utils/dom/dom.js
index 118498bc3..739344c98 100644
--- a/core/modules/utils/dom/dom.js
+++ b/core/modules/utils/dom/dom.js
@@ -231,4 +231,34 @@ exports.copyStyles = function(srcDomNode,dstDomNode) {
 	$tw.utils.setStyles(dstDomNode,$tw.utils.getComputedStyles(srcDomNode));
 };
 
+/*
+Copy plain text to the clipboard on browsers that support it
+*/
+exports.copyToClipboard = function(text,options) {
+	options = options || {};
+	var textArea = document.createElement("textarea");
+	textArea.style.position = "fixed";
+	textArea.style.top = 0;
+	textArea.style.left = 0;
+	textArea.style.width = "2em";
+	textArea.style.height = "2em";
+	textArea.style.padding = 0;
+	textArea.style.border = "none";
+	textArea.style.outline = "none";
+	textArea.style.boxShadow = "none";
+	textArea.style.background = "transparent";
+	textArea.value = text;
+	document.body.appendChild(textArea);
+	textArea.select();
+	var succeeded = false;
+	try {
+		succeeded = document.execCommand("copy");
+	} catch (err) {
+	}
+	if(!options.doNotNotify) {
+		$tw.notifier.display(succeeded ? "$:/language/Notifications/CopiedToClipboard/Succeeded" : "$:/language/Notifications/CopiedToClipboard/Failed");
+	}
+	document.body.removeChild(textArea);
+};
+
 })();
diff --git a/editions/tw5.com/tiddlers/messages/WidgetMessage_ tm-copy-to-clipboard.tid b/editions/tw5.com/tiddlers/messages/WidgetMessage_ tm-copy-to-clipboard.tid
new file mode 100644
index 000000000..70cf2a24a
--- /dev/null
+++ b/editions/tw5.com/tiddlers/messages/WidgetMessage_ tm-copy-to-clipboard.tid	
@@ -0,0 +1,25 @@
+caption: tm-copy-to-clipboard
+created: 20171215150056004
+modified: 20171215150600888
+tags: Messages
+title: WidgetMessage: tm-copy-to-clipboard
+type: text/vnd.tiddlywiki
+
+The "copy to clipboard" message attempts to copy the specified text to the clipboard. If it succeeds, the tiddler [[$:/language/Notifications/CopiedToClipboard/Succeeded]] is displayed as a notification. If the browser doesn't permit the operation, the tiddler [[$:/language/Notifications/CopiedToClipboard/Failed]] is displayed instead.
+
+It requires the following properties on the `event` object:
+
+|!Name |!Description |
+|param |Text to be copied to the clipboard |
+
+This message is usually generated with the ButtonWidget. It is handled by the TiddlyWiki core.
+
+! Example
+
+This example copies the current time to the clipboard:
+
+<$macrocall $name='wikitext-example-without-html'
+src='<$button message="tm-copy-to-clipboard" param=<<now>>>
+Copy date to clipboard
+</$button>'/>
+