Alex A. Naanou 7b755b413c refactoring + lots of tweaks and fixes...
Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
2023-10-14 22:49:02 +03:00

120 lines
3.0 KiB
JavaScript
Executable File

/**********************************************************************
*
*
*
**********************************************************************/
HTMLTextAreaElement.prototype.updateSize = function(){
this.style.height = ''
this.style.height = this.scrollHeight + 'px'
return this }
HTMLTextAreaElement.prototype.autoUpdateSize = function(){
var that = this
this.addEventListener('input',
function(evt){
that.updateSize() })
return this }
HTMLTextAreaElement.prototype.getTextGeometry = function(){
var offset = this.selectionStart
var text = this.value
// get the relevant styles...
var style = getComputedStyle(this)
var s = {}
for(var i=0; i < style.length; i++){
var k = style[i]
if(k.startsWith('font')
|| k.startsWith('line')
|| k.startsWith('white-space')){
s[k] = style[k] } }
var carret = document.createElement('span')
carret.innerText = '|'
carret.style.margin = '0px'
carret.style.padding = '0px'
var span = document.createElement('span')
span.innerText = text.slice(0, offset)
Object.assign(span.style, {
...s,
position: 'fixed',
display: 'block',
top: '-100%',
left: '-100%',
width: this.offsetWidth + 'px',
height: this.scrollHeight + 'px',
padding: style.padding,
outline: 'solid 1px red',
pointerEvents: 'none',
})
span.append(carret)
document.body.append(span)
var res = {
length: text.length,
lines: Math.floor(this.offsetHeight / carret.offsetHeight),
line: Math.floor(carret.offsetTop / carret.offsetHeight),
offset: offset,
offsetLeft: carret.offsetLeft,
offsetTop: carret.offsetTop,
}
span.remove()
return res }
// calculate number of lines in text area (both wrapped and actual lines)
Object.defineProperty(HTMLTextAreaElement.prototype, 'heightLines', {
enumerable: false,
get: function(){
var style = getComputedStyle(this)
return Math.floor(
(this.scrollHeight
- parseFloat(style.paddingTop)
- parseFloat(style.paddingBottom))
/ (parseFloat(style.lineHeight)
|| parseFloat(style.fontSize))) }, })
Object.defineProperty(HTMLTextAreaElement.prototype, 'lines', {
enumerable: false,
get: function(){
return this.value
.split(/\n/g)
.length }, })
// XXX this does not account for wrapping...
Object.defineProperty(HTMLTextAreaElement.prototype, 'caretLine', {
enumerable: false,
get: function(){
var offset = this.selectionStart
return offset != null ?
this.value
.slice(0, offset)
.split(/\n/g)
.length
: undefined }, })
Object.defineProperty(HTMLTextAreaElement.prototype, 'caretOffset', {
enumerable: false,
get: function(){
var offset = this.selectionStart
var r = document.createRange()
r.setStart(this, offset)
r.setEnd(this, offset)
var rect = r.getBoundingClientRect()
return {
top: rect.top,
left: rect.left,
} },
})
/**********************************************************************
* vim:set ts=4 sw=4 : */