GitHub RTL Comment Blocks

A userscript that adds a button to insert RTL text blocks in comments

目前為 2017-01-12 提交的版本,檢視 最新版本

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @name          GitHub RTL Comment Blocks
// @version       1.2.2
// @description   A userscript that adds a button to insert RTL text blocks in comments
// @license       https://creativecommons.org/licenses/by-sa/4.0/
// @namespace     http://github.com/Mottie
// @include       https://github.com/*
// @include       https://gist.github.com/*
// @run-at        document-idle
// @grant         GM_addStyle
// @connect       github.com
// @author        Rob Garrison
// ==/UserScript==
/* jshint unused:true, esnext:true */
/* global GM_addStyle */
(function() {
	"use strict";

	let targets, timer, busyTimer,
		busy = false;

	const icon = `
		<svg class="octicon" xmlns="http://www.w3.org/2000/svg" width="14" height="14" viewBox="0 0 14 14">
			<path d="M14 3v8l-4-4m-7 7V6C1 6 0 5 0 3s1-3 3-3h7v2H9v12H7V2H5v12H3z"/>
		</svg>`,

		// maybe using &#x2067; RTL text &#x2066; (isolates) is a better combo?
		openRTL = "&rlm;",  // https://en.wikipedia.org/wiki/Right-to-left_mark
		closeRTL = "&lrm;", // https://en.wikipedia.org/wiki/Left-to-right_mark

		regexOpen = /\u200f/ig,
		regexClose = /\u200e/ig,
		regexSplit = /(\u200f|\u200e)/ig;

	GM_addStyle(`
		.ghu-rtl-css { direction:rtl; text-align:right; }
		/* delegated binding; ignore clicks on svg & path */
		.ghu-rtl > * { pointer-events:none; }
		/* override RTL on code blocks */
		.js-preview-body pre, .markdown-body pre, .js-preview-body code, .markdown-body code {
			direction:ltr;
			text-align:left;
			unicode-bidi:normal;
		}
	`);

	// Add monospace font toggle
	function addRtlButton() {
		busy = true;
		let el, button,
			toolbars = $$(".toolbar-commenting"),
			indx = toolbars.length;
		if (indx) {
			button = document.createElement("button");
			button.type = "button";
			button.className = "ghu-rtl toolbar-item tooltipped tooltipped-n";
			button.setAttribute("aria-label", "RTL");
			button.setAttribute("tabindex", "-1");
			button.innerHTML = icon;
			while (indx--) {
				el = toolbars[indx];
				if (!$(".ghu-rtl", el)) {
					el.insertBefore(button.cloneNode(true), el.childNodes[0]);
				}
			}
		}
		checkRTL();
		clearBusy();
	}

	function checkContent(el) {
		// check the contents, and wrap in either a span or div
		let indx, // useDiv,
			html = el.innerHTML,
			parts = html.split(regexSplit),
			len = parts.length;
		for (indx = 0; indx < len; indx++) {
			if (regexOpen.test(parts[indx])) {
				// check if the content contains HTML
				// useDiv = regexTestHTML.test(parts[indx + 1]);
				// parts[indx] = (useDiv ? "<div" : "<span") + " class='ghu-rtl-css'>";
				parts[indx] = "<div class='ghu-rtl-css'>";
			} else if (regexClose.test(parts[indx])) {
				// parts[indx] = useDiv ? "</div>" : "</span>";
				parts[indx] = "</div>";
			}
		}
		el.innerHTML = parts.join("");
		// remove empty paragraph wrappers (may have previously contained the mark)
		return el.innerHTML.replace(/<p><\/p>/g, "");
	}

	function checkRTL() {
		let clone,
			indx = 0,
			div = document.createElement("div"),
			containers = $$(".js-preview-body, .markdown-body"),
			len = containers.length,
			// main loop
			loop = function() {
				let el, tmp,
					max = 0;
				while (max < 10 && indx < len) {
					if (indx > len) {
						return;
					}
					el = containers[indx];
					tmp = el.innerHTML;
					if (regexOpen.test(tmp) || regexClose.test(tmp)) {
						clone = div.cloneNode();
						clone.innerHTML = tmp;
						// now we can replace all instances
						el.innerHTML = checkContent(clone);
						max++;
					}
					indx++;
				}
				if (indx < len) {
					setTimeout(function() {
						busy = true;
						loop();
						clearBusy();
					}, 200);
				}
			};
		busy = true;
		loop();
		clearBusy();
	}

	// This method cuts out 3 extra calls to addRtlButton()
	// when a preview tab is used.
	function clearBusy() {
		clearTimeout(busyTimer);
		busyTimer = setTimeout(function() {
			busy = false;
		}, 200);
	}

	function $(selector, el) {
		return (el || document).querySelector(selector);
	}
	function $$(selector, el) {
		return Array.from((el || document).querySelectorAll(selector));
	}
	function closest(selector, el) {
		while (el && el.nodeType === 1) {
			if (el.matches(selector)) {
				return el;
			}
			el = el.parentNode;
		}
		return null;
	}

	function addBindings() {
		$("body").addEventListener("click", function(event) {
			let textarea,
				target = event.target;
			if (target && target.classList.contains("ghu-rtl")) {
				textarea = closest(".previewable-comment-form", target);
				textarea = $(".comment-form-textarea", textarea);
				textarea.focus();
				// add extra white space around the tags
				surroundSelectedText(textarea, " " + openRTL + " ", " " + closeRTL + " ");
				return false;
			}
		});
	}

	targets = $$("#js-repo-pjax-container, #js-pjax-container, .js-preview-body");

	Array.prototype.forEach.call(targets, function(target) {
		new MutationObserver(function(mutations) {
			mutations.forEach(function(mutation) {
				let mtarget = mutation.target;
				// preform checks before adding code wrap to minimize function calls
				// update after comments are edited
				if (mtarget === target || mtarget.matches(".js-comment-body, .js-preview-body")) {
					clearTimeout(timer);
					setTimeout(function() {
						if (!busy) {
							addRtlButton();
						}
					}, 100);
				}
			});
		}).observe(target, {
			childList: true,
			subtree: true
		});
	});

	addBindings();
	addRtlButton();

	/*eslint-disable */
	/* HEAVILY MODIFIED from https://github.com/timdown/rangyinputs
	 code was unwrapped & unneeded code was removed
	*/
	/**
	* @license Rangy Inputs, a jQuery plug-in for selection and caret manipulation within textareas and text inputs.
	*
	* https://github.com/timdown/rangyinputs
	*
	* For range and selection features for contenteditable, see Rangy.
	* http://code.google.com/p/rangy/
	*
	* Depends on jQuery 1.0 or later.
	*
	* Copyright 2014, Tim Down
	* Licensed under the MIT license.
	* Version: 1.2.0
	* Build date: 30 November 2014
	*/
	var UNDEF = "undefined";
	var getSelection, setSelection, surroundSelectedText;

	// Trio of isHost* functions taken from Peter Michaux's article:
	// http://peter.michaux.ca/articles/feature-detection-state-of-the-art-browser-scripting
	function isHostMethod(object, property) {
		var t = typeof object[property];
		return t === "function" || (!!(t == "object" && object[property])) || t == "unknown";
	}
	function isHostProperty(object, property) {
		return typeof(object[property]) != UNDEF;
	}
	function isHostObject(object, property) {
		return !!(typeof(object[property]) == "object" && object[property]);
	}
	function fail(reason) {
		if (window.console && window.console.log) {
			window.console.log("RangyInputs not supported in your browser. Reason: " + reason);
		}
	}

	function adjustOffsets(el, start, end) {
		if (start < 0) {
			start += el.value.length;
		}
		if (typeof end == UNDEF) {
			end = start;
		}
		if (end < 0) {
			end += el.value.length;
		}
		return { start: start, end: end };
	}

	function makeSelection(el, start, end) {
		return {
			start: start,
			end: end,
			length: end - start,
			text: el.value.slice(start, end)
		};
	}

	function getBody() {
		return isHostObject(document, "body") ? document.body : document.getElementsByTagName("body")[0];
	}

	var testTextArea = document.createElement("textarea");
	getBody().appendChild(testTextArea);

	if (isHostProperty(testTextArea, "selectionStart") && isHostProperty(testTextArea, "selectionEnd")) {
		getSelection = function(el) {
			var start = el.selectionStart, end = el.selectionEnd;
			return makeSelection(el, start, end);
		};

		setSelection = function(el, startOffset, endOffset) {
			var offsets = adjustOffsets(el, startOffset, endOffset);
			el.selectionStart = offsets.start;
			el.selectionEnd = offsets.end;
		};
	} else if (isHostMethod(testTextArea, "createTextRange") && isHostObject(document, "selection") &&
		isHostMethod(document.selection, "createRange")) {

		getSelection = function(el) {
			var start = 0, end = 0, normalizedValue, textInputRange, len, endRange;
			var range = document.selection.createRange();

			if (range && range.parentElement() == el) {
				len = el.value.length;

				normalizedValue = el.value.replace(/\r\n/g, "\n");
				textInputRange = el.createTextRange();
				textInputRange.moveToBookmark(range.getBookmark());
				endRange = el.createTextRange();
				endRange.collapse(false);
				if (textInputRange.compareEndPoints("StartToEnd", endRange) > -1) {
					start = end = len;
				} else {
					start = -textInputRange.moveStart("character", -len);
					start += normalizedValue.slice(0, start).split("\n").length - 1;
					if (textInputRange.compareEndPoints("EndToEnd", endRange) > -1) {
						end = len;
					} else {
						end = -textInputRange.moveEnd("character", -len);
						end += normalizedValue.slice(0, end).split("\n").length - 1;
					}
				}
			}

			return makeSelection(el, start, end);
		};

		// Moving across a line break only counts as moving one character in a TextRange, whereas a line break in
		// the textarea value is two characters. This function corrects for that by converting a text offset into a
		// range character offset by subtracting one character for every line break in the textarea prior to the
		// offset
		var offsetToRangeCharacterMove = function(el, offset) {
			return offset - (el.value.slice(0, offset).split("\r\n").length - 1);
		};

		setSelection = function(el, startOffset, endOffset) {
			var offsets = adjustOffsets(el, startOffset, endOffset);
			var range = el.createTextRange();
			var startCharMove = offsetToRangeCharacterMove(el, offsets.start);
			range.collapse(true);
			if (offsets.start == offsets.end) {
				range.move("character", startCharMove);
			} else {
				range.moveEnd("character", offsetToRangeCharacterMove(el, offsets.end));
				range.moveStart("character", startCharMove);
			}
			range.select();
		};
	} else {
		getBody().removeChild(testTextArea);
		fail("No means of finding text input caret position");
		return;
	}
	// Clean up
	getBody().removeChild(testTextArea);

	function getValueAfterPaste(el, text) {
		var val = el.value, sel = getSelection(el), selStart = sel.start;
		return {
			value: val.slice(0, selStart) + text + val.slice(sel.end),
			index: selStart,
			replaced: sel.text
		};
	}

	function pasteTextWithCommand(el, text) {
		el.focus();
		var sel = getSelection(el);

		// Hack to work around incorrect delete command when deleting the last word on a line
		setSelection(el, sel.start, sel.end);
		if (text === "") {
			document.execCommand("delete", false, null);
		} else {
			document.execCommand("insertText", false, text);
		}

		return {
			replaced: sel.text,
			index: sel.start
		};
	}

	function pasteTextWithValueChange(el, text) {
		el.focus();
		var valueAfterPaste = getValueAfterPaste(el, text);
		el.value = valueAfterPaste.value;
		return valueAfterPaste;
	}

	var pasteText = function(el, text) {
		var valueAfterPaste = getValueAfterPaste(el, text);
		try {
			var pasteInfo = pasteTextWithCommand(el, text);
			if (el.value == valueAfterPaste.value) {
				pasteText = pasteTextWithCommand;
				return pasteInfo;
			}
		} catch (ex) {
			// Do nothing and fall back to changing the value manually
		}
		pasteText = pasteTextWithValueChange;
		el.value = valueAfterPaste.value;
		return valueAfterPaste;
	};

	var updateSelectionAfterInsert = function(el, startIndex, text, selectionBehaviour) {
		var endIndex = startIndex + text.length;

		selectionBehaviour = (typeof selectionBehaviour == "string") ?
		selectionBehaviour.toLowerCase() : "";

		if ((selectionBehaviour == "collapsetoend" || selectionBehaviour == "select") && /[\r\n]/.test(text)) {
			// Find the length of the actual text inserted, which could vary
			// depending on how the browser deals with line breaks
			var normalizedText = text.replace(/\r\n/g, "\n").replace(/\r/g, "\n");
			endIndex = startIndex + normalizedText.length;
			var firstLineBreakIndex = startIndex + normalizedText.indexOf("\n");

			if (el.value.slice(firstLineBreakIndex, firstLineBreakIndex + 2) == "\r\n") {
				// Browser uses \r\n, so we need to account for extra \r characters
				endIndex += normalizedText.match(/\n/g).length;
			}
		}

		switch (selectionBehaviour) {
			case "collapsetostart":
				setSelection(el, startIndex, startIndex);
				break;
			case "collapsetoend":
				setSelection(el, endIndex, endIndex);
				break;
			case "select":
				setSelection(el, startIndex, endIndex);
				break;
		}
	};

	surroundSelectedText = function(el, before, after, selectionBehaviour) {
		if (typeof after == UNDEF) {
			after = before;
		}
		var sel = getSelection(el);
		var pasteInfo = pasteText(el, before + sel.text + after);
		updateSelectionAfterInsert(el, pasteInfo.index + before.length, sel.text, selectionBehaviour || "select");
	};
	/*eslint-enable */

})();