A userscript that adds a button to insert RTL text blocks in comments
当前为
// ==UserScript==
// @name GitHub RTL Comment Blocks
// @version 1.0.0
// @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/*
// @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,
busy = false;
// ${text} is not an es6 placeholder!
const rtlBlock = '<div dir="rtl" align="right">${text}</div>',
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>
`;
// delegated binding; ignore clicks on svg & path
GM_addStyle('.ghu-rtl > * { pointer-events:none; }');
// Add monospace font toggle
function addRtlButton() {
busy = true;
var el, button,
toolbars = document.querySelectorAll(".toolbar-commenting"),
indx = toolbars.length;
while (indx--) {
el = toolbars[indx];
if (!el.querySelector(".ghu-rtl")) {
button = document.querySelector("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;
el.insertBefore(button, el.childNodes[0]);
}
}
busy = false;
}
function closest(el, selector) {
while (el && el.nodeName !== 'BODY' && !el.matches(selector)) {
el = el.parentNode;
}
return el && el.matches(selector) ? el : [];
}
function addBindings() {
document.querySelector('body').addEventListener('click', function(event) {
var textarea, str,
target = event.target;
if (target && target.classList.contains('ghu-rtl')) {
textarea = closest(target, '.previewable-comment-form');
textarea = textarea.querySelector('.comment-form-textarea');
textarea.focus();
str = rtlBlock.split('${text}');
// insert text - before: "<div dir='rtl' align='right'>", after: "</div>"
surroundSelectedText(textarea, str[0], str[1]);
return false;
}
});
}
targets = document.querySelectorAll([
'#js-repo-pjax-container',
'#js-pjax-container',
'.js-preview-body'
].join(','));
Array.prototype.forEach.call(targets, function(target) {
new MutationObserver(function(mutations) {
mutations.forEach(function(mutation) {
// preform checks before adding code wrap to minimize function calls
if (!busy && mutation.target === target) {
addRtlButton();
}
});
}).observe(target, {
childList: true,
subtree: true
});
});
addBindings();
addRtlButton();
/* 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");
};
})();