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p.p-4
| click right image icon and select movie, pdf or image files.
form#post-form.flex.flex-row.items-center.bottom-0.my-2.mx-2(action='#' method='post' enctype="multipart/form-data" onsubmit='return false;')
.flex.w-full.pl-3.py-3.border.rounded-3xl.items-center.bg-white
#message-content.overflow-y-scroll.max-h-60.w-full(name='content' contenteditable='true' class='focus:outline-none' placeholder="input message..." )
.flex
input#message-files.hidden(type='file' name='message-files[]' accept='image/*,application/pdf,text/plain,video/*,audio/*' multiple='multiple')
button#message-image-btn.flex.items-center.justify-center.w-10.text-green-400(class='focus:outline-none hover:text-green-600')
svg.w-5.h-5(fill='none', stroke='currentColor', viewbox='0 0 24 24', xmlns='http://www.w3.org/2000/svg')
path(stroke-linecap='round', stroke-linejoin='round', stroke-width='2', d='M4 16l4.586-4.586a2 2 0 012.828 0L16 16m-2-2l1.586-1.586a2 2 0 012.828 0L20 14m-6-6h.01M6 20h12a2 2 0 002-2V6a2 2 0 00-2-2H6a2 2 0 00-2 2v12a2 2 0 002 2z')
button#message-submit-btn.flex.items-center.justify-center.h-10.w-10.mr-2.rounded-full.bg-blue-500.text-white(class='hover:bg-gray-300 focus:outline-none')
svg.w-5.h-5.transform.rotate-90.-mr-px(fill='none', stroke='currentColor', viewbox='0 0 24 24', xmlns='http://www.w3.org/2000/svg')
path(stroke-linecap='round', stroke-linejoin='round', stroke-width='2', d='M12 19l9 2-9-18-9 18 9-2zm0 0v-8')
/* import tailwind CSS */
/* like placeholder */
[contenteditable=true]:empty:before {
content: attr(placeholder);
opacity: 0.5;
pointer-events: none;
display:block;
}
/* set image size */
[contenteditable=true] img{ max-width:80%;border:1px solid #DDD;max-height:120px;}
/** import external script : pdf.js
* ------------------------------
* Reference links the below
* ------------------------------
* PDF : https://mozilla.github.io/pdf.js/examples/index.html#interactive-examples
* Movie : https://stackoverflow.com/questions/50842933/how-to-display-thumnail-or-preview-for-current-file-upload
*/
// save time to write document.querySelectorAll
const $ = (selector)=>{
const elements = document.querySelectorAll(selector);
if(!elements.length) return;
else if(elements.length===1) return elements[0];
else return elements;
};
$('#message-image-btn').addEventListener('click',()=>{
$('#message-files').dispatchEvent(new MouseEvent('click'));
return false;
});
function insertPdfPreviewImg(input_file,target_element,callback){
const pdfjsLib = window['pdfjs-dist/build/pdf'];
pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.11.338/pdf.worker.min.js';
const reader = new FileReader();
reader.readAsArrayBuffer(input_file);
reader.onload= e => {
const pdfData = new Uint8Array(e.target.result);
var loadingTask = pdfjsLib.getDocument({data: pdfData});
loadingTask.promise.then(function(pdf) {
console.log('PDF loaded');
var pageNumber = 1;
pdf.getPage(pageNumber).then((page) => {
//- console.log('PDF Page loaded');
const viewport = page.getViewport({scale: 1});
const canvas = document.createElement('canvas');
const context = canvas.getContext('2d');
canvas.height = viewport.height;
canvas.width = viewport.width;
const renderContext = {
canvasContext: context,
viewport: viewport
};
const renderTask = page.render(renderContext);
renderTask.promise.then(function () {
const image = document.createElement('img');
image.style.cursor='pointer';
image.className='preview pdf';
image.src = canvas.toDataURL();
target_element.appendChild(image);
if(callback) callback(image);
});
});
}, err => console.error );
}
}
function insertImagePreviewImg(input_file,target_element,callback){
const reader = new FileReader();
reader.readAsDataURL(input_file);
reader.onload= e => {
const result = e.target.result;
const image = document.createElement('img');
image.style.cursor='pointer';
image.className='preview image';
image.src = result;
target_element.appendChild(image);
if(callback) callback(image);
}
}
function insertVideoPreviewImg(input_file,target_element,callback){
const reader = new FileReader();
reader.readAsDataURL(input_file);
reader.onload= e => {
const result = e.target.result;
const canvas = document.createElement('canvas');
const image = document.createElement('img');
const video = document.createElement('video');
const source = document.createElement('source');
source.src = URL.createObjectURL(input_file);
video.appendChild(source);
video.addEventListener('loadedmetadata',e=>{
const v = e.target;
const duration = v.duration;
canvas.width = v.videoWidth;
canvas.height = v.videoHeight;
video.currentTime = Math.ceil(duration/2);
video.addEventListener('timeupdate',()=>{
const ctx = canvas.getContext('2d');
ctx.drawImage(video,0,0,v.videoWidth,v.videoHeight);
image.style.cursor='pointer';
image.className='preview movie';
image.src = canvas.toDataURL();
target_element.appendChild(image);
if(callback) callback(image);
},{once:true});
})
}
}
$('#message-files').onchange = e =>{
const input = e.target;
const files = e.target.files;
if(FileReader && files && files.length){
const target_element = $('#message-content');
for ( var i = 0; file= files[i]; i++ ) {
if(file.type==='application/pdf') {
insertPdfPreviewImg(file,target_element);
}else if(file.type.indexOf('video/')!==-1) {
insertVideoPreviewImg(file,target_element);
} else if(file.type.indexOf('image/')!==-1){
insertImagePreviewImg(file,target_element);
}
}
}
}
Also see: Tab Triggers