jellyfish-web/src/elements/emby-textarea/emby-textarea.js
2023-03-09 00:20:11 -05:00

137 lines
4.1 KiB
JavaScript

import './emby-textarea.scss';
import 'webcomponents.js/webcomponents-lite';
import '../emby-input/emby-input';
/**
* Calculates the vertical padding of the element
* @param textarea
* @returns {number}
*/
function calculateOffset(textarea) {
const style = window.getComputedStyle(textarea, null);
const props = ['paddingTop', 'paddingBottom'];
let offset = 0;
for (let i = 0; i < props.length; i++) {
offset += parseInt(style[props[i]], 10);
}
return offset;
}
/* eslint-disable indent */
function autoGrow(textarea, maxLines) {
const self = this;
if (maxLines === undefined) {
maxLines = 999;
}
let offset;
function reset() {
textarea.rows = 1;
offset = calculateOffset(textarea);
self.rows = textarea.rows || 1;
self.lineHeight = (textarea.scrollHeight / self.rows) - (offset / self.rows);
self.maxAllowedHeight = (self.lineHeight * maxLines) - offset;
}
function autogrowFn() {
if (!self.lineHeight || self.lineHeight <= 0) {
reset();
}
if (self.lineHeight <= 0) {
textarea.style.overflowY = 'scroll';
textarea.style.height = 'auto';
textarea.rows = 3;
return;
}
let newHeight = 0;
if ((textarea.scrollHeight - offset) > self.maxAllowedHeight) {
textarea.style.overflowY = 'scroll';
newHeight = self.maxAllowedHeight;
} else {
textarea.style.overflowY = 'hidden';
textarea.style.height = 'auto';
newHeight = textarea.scrollHeight/* - offset*/;
}
textarea.style.height = newHeight + 'px';
}
// Call autogrowFn() when textarea's value is changed
textarea.addEventListener('input', autogrowFn);
textarea.addEventListener('focus', autogrowFn);
textarea.addEventListener('valueset', autogrowFn);
autogrowFn();
}
const EmbyTextAreaPrototype = Object.create(HTMLTextAreaElement.prototype);
let elementId = 0;
if (Object.getOwnPropertyDescriptor && Object.defineProperty) {
const descriptor = Object.getOwnPropertyDescriptor(HTMLTextAreaElement.prototype, 'value');
// descriptor returning null in webos
if (descriptor && descriptor.configurable) {
const baseSetMethod = descriptor.set;
descriptor.set = function (value) {
baseSetMethod.call(this, value);
this.dispatchEvent(new CustomEvent('valueset', {
bubbles: false,
cancelable: false
}));
};
Object.defineProperty(HTMLTextAreaElement.prototype, 'value', descriptor);
}
}
EmbyTextAreaPrototype.createdCallback = function () {
if (!this.id) {
this.id = 'embytextarea' + elementId;
elementId++;
}
};
EmbyTextAreaPrototype.attachedCallback = function () {
if (this.classList.contains('emby-textarea')) {
return;
}
this.rows = 1;
this.classList.add('emby-textarea');
const parentNode = this.parentNode;
const label = this.ownerDocument.createElement('label');
label.innerText = this.getAttribute('label') || '';
label.classList.add('textareaLabel');
label.htmlFor = this.id;
parentNode.insertBefore(label, this);
this.addEventListener('focus', function () {
label.classList.add('textareaLabelFocused');
label.classList.remove('textareaLabelUnfocused');
});
this.addEventListener('blur', function () {
label.classList.remove('textareaLabelFocused');
label.classList.add('textareaLabelUnfocused');
});
this.label = function (text) {
label.innerText = text;
};
new autoGrow(this);
};
document.registerElement('emby-textarea', {
prototype: EmbyTextAreaPrototype,
extends: 'textarea'
});
/* eslint-enable indent */