zulip/static/third/jquery-autosize/jquery.autosize.js

/** @preserve
 Software from "Autosize 1.13", a jQuery plugin for textareas, is
 Copyright (c) 2012 Jack Moore and is provided under the following license:
 --
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 --
*/

// Autosize 1.13 - jQuery plugin for textareas
// (c) 2012 Jack Moore - jacklmoore.com
// license: www.opensource.org/licenses/mit-license.php

(function ($) {
	var
	defaults = {
		className: 'autosizejs',
		append: "",
		callback: false
	},
	hidden = 'hidden',
	borderBox = 'border-box',
	lineHeight = 'lineHeight',
	copy = '<textarea tabindex="-1" style="position:absolute; top:-9999px; left:-9999px; right:auto; bottom:auto; -moz-box-sizing:content-box; -webkit-box-sizing:content-box; box-sizing:content-box; word-wrap:break-word; height:0 !important; min-height:0 !important; overflow:hidden;"/>',
	// line-height is omitted because IE7/IE8 doesn't return the correct value.
	copyStyle = [
		'fontFamily',
		'fontSize',
		'fontWeight',
		'fontStyle',
		'letterSpacing',
		'textTransform',
		'wordSpacing',
		'textIndent'
	],
	oninput = 'oninput',
	onpropertychange = 'onpropertychange',
	test = $(copy)[0];

	// For testing support in old FireFox
	test.setAttribute(oninput, "return");

	if ($.isFunction(test[oninput]) || onpropertychange in test) {

		// test that line-height can be accurately copied to avoid
		// incorrect value reporting in old IE and old Opera
		$(test).css(lineHeight, '99px');
		if ($(test).css(lineHeight) === '99px') {
			copyStyle.push(lineHeight);
		}

		$.fn.autosize = function (options) {
			options = $.extend({}, defaults, options || {});

			return this.each(function () {
				var
				ta = this,
				$ta = $(ta),
				mirror,
				minHeight = $ta.height(),
				maxHeight = parseInt($ta.css('maxHeight'), 10),
				active,
				i = copyStyle.length,
				resize,
				boxOffset = 0,
				value = ta.value,
				callback = $.isFunction(options.callback);

				if ($ta.css('box-sizing') === borderBox || $ta.css('-moz-box-sizing') === borderBox || $ta.css('-webkit-box-sizing') === borderBox){
					boxOffset = $ta.outerHeight() - $ta.height();
				}

				if ($ta.data('mirror') || $ta.data('ismirror')) {
					// if autosize has already been applied, exit.
					// if autosize is being applied to a mirror element, exit.
					return;
				} else {
					mirror = $(copy).data('ismirror', true).addClass(options.className)[0];

					resize = $ta.css('resize') === 'none' ? 'none' : 'horizontal';

					$ta.data('mirror', $(mirror)).css({
						overflow: hidden,
						overflowY: hidden,
						wordWrap: 'break-word',
						resize: resize
					});
				}

				// Opera returns '-1px' when max-height is set to 'none'.
				maxHeight = maxHeight && maxHeight > 0 ? maxHeight : 9e4;

				// Using mainly bare JS in this function because it is going
				// to fire very often while typing, and needs to very efficient.
				function adjust() {
					var height, overflow, original;

					// the active flag keeps IE from tripping all over itself.  Otherwise
					// actions in the adjust function will cause IE to call adjust again.
					if (!active) {
						active = true;
						mirror.value = ta.value + options.append;
						mirror.style.overflowY = ta.style.overflowY;
						original = parseInt(ta.style.height,10);

						// Update the width in case the original textarea width has changed
						mirror.style.width = $ta.css('width');

						// Needed for IE to reliably return the correct scrollHeight
						mirror.scrollTop = 0;

						// Set a very high value for scrollTop to be sure the
						// mirror is scrolled all the way to the bottom.
						mirror.scrollTop = 9e4;

						height = mirror.scrollTop;
						overflow = hidden;
						if (height > maxHeight) {
							height = maxHeight;
							overflow = 'scroll';
						} else if (height < minHeight) {
							height = minHeight;
						}
						height += boxOffset;
						ta.style.overflowY = overflow;

						if (original !== height) {
							ta.style.height = height + 'px';
							if (callback) {
								options.callback.call(ta);
							}
						}
						
						// This small timeout gives IE a chance to draw it's scrollbar
						// before adjust can be run again (prevents an infinite loop).
						setTimeout(function () {
							active = false;
						}, 1);
					}
				}

				// mirror is a duplicate textarea located off-screen that
				// is automatically updated to contain the same text as the
				// original textarea.  mirror always has a height of 0.
				// This gives a cross-browser supported way getting the actual
				// height of the text, through the scrollTop property.
				while (i--) {
					mirror.style[copyStyle[i]] = $ta.css(copyStyle[i]);
				}

				$('body').append(mirror);

				if (onpropertychange in ta) {
					if (oninput in ta) {
						// Detects IE9.  IE9 does not fire onpropertychange or oninput for deletions,
						// so binding to onkeyup to catch most of those occassions.  There is no way that I
						// know of to detect something like 'cut' in IE9.
						ta[oninput] = ta.onkeyup = adjust;
					} else {
						// IE7 / IE8
						ta[onpropertychange] = adjust;
					}
				} else {
					// Modern Browsers
					ta[oninput] = adjust;

					// The textarea overflow is now hidden.  But Chrome doesn't reflow the text after the scrollbars are removed.
					// This is a hack to get Chrome to reflow it's text.
					ta.value = '';
					ta.value = value;
				}

				$(window).resize(adjust);

				// Allow for manual triggering if needed.
				$ta.bind('autosize', adjust);

				// Call adjust in case the textarea already contains text.
				adjust();
			});
		};
	} else {
		// Makes no changes for older browsers (FireFox3- and Safari4-)
		$.fn.autosize = function (callback) {
			return this;
		};
	}

}(window.jQuery || window.Zepto));