title: $:/plugins/local/copy-codeblock/copy-codeblock.js
type: application/javascript
module-type: widget

/*\
title: $:/plugins/local/copy-codeblock/copy-codeblock.js
type: application/javascript
module-type: widget

Adds a copy button to code blocks.
\*/
(function() {
"use strict";

var CodeBlockWidget = require("$:/core/modules/widgets/codeblock.js").codeblock;

var CopyCodeBlockWidget = function(parseTreeNode,options) {
	this.initialise(parseTreeNode,options);
};

CopyCodeBlockWidget.prototype = new CodeBlockWidget();
CopyCodeBlockWidget.prototype.constructor = CopyCodeBlockWidget;

CopyCodeBlockWidget.prototype.postRender = function() {
	var self = this,
		preNode = this.domNodes[0],
		previousNode,
		button;

	// Preserve syntax highlighting supplied by the highlight plugin.
	if(CodeBlockWidget.prototype.postRender) {
		CodeBlockWidget.prototype.postRender.call(this);
	}

	if(!$tw.browser || !preNode || preNode.isTiddlyWikiFakeDom) {
		return;
	}

	// The system code view already renders its own copy button.
	previousNode = preNode.previousElementSibling;
	if(previousNode && previousNode.querySelector && previousNode.querySelector(".tc-image-copy-clipboard")) {
		return;
	}

	preNode.style.position = "relative";
	preNode.style.paddingRight = "5em";

	button = this.document.createElement("button");
	button.setAttribute("type","button");
	button.setAttribute("aria-label","Copy code");
	button.setAttribute("title","Copy code");
	button.className = "tc-btn-invisible tc-copy-codeblock-button";
	button.textContent = "Copy";
	button.style.position = "absolute";
	button.style.top = "0.5em";
	button.style.right = "0.5em";
	button.style.zIndex = "1";
	button.style.padding = "0.2em 0.45em";
	button.style.cursor = "pointer";

	button.addEventListener("click",function(event) {
		event.preventDefault();
		event.stopPropagation();
		$tw.utils.copyToClipboard(self.getAttribute("code",""));
	});

	preNode.appendChild(button);
};

exports.codeblock = CopyCodeBlockWidget;

})();