Files
liceo-ariosto/media/plg_media-action_resize/js/resize.js
2025-06-17 11:53:18 +02:00

89 lines
2.6 KiB
JavaScript

/**
* @copyright (C) 2018 Open Source Matters, Inc. <https://www.joomla.org>
* @license GNU General Public License version 2 or later; see LICENSE.txt
*/
let formElements;
let activated = false;
// Update image
const resize = (width, height, image) => {
// The canvas where we will resize the image
let canvas = document.createElement('canvas');
canvas.width = width;
canvas.height = height;
canvas.getContext('2d').drawImage(image, 0, 0, width, height);
// The format
const format = Joomla.MediaManager.Edit.original.extension === 'jpg' ? 'jpeg' : Joomla.MediaManager.Edit.original.extension;
// The quality
const quality = formElements.resizeQuality.value;
// Creating the data from the canvas
Joomla.MediaManager.Edit.current.contents = canvas.toDataURL(`image/${format}`, quality);
// Updating the preview element
image.width = width;
image.height = height;
image.src = Joomla.MediaManager.Edit.current.contents;
// Update the width input box
formElements.resizeWidth.value = parseInt(width, 10);
// Update the height input box
formElements.resizeHeight.value = parseInt(height, 10);
// Notify the app that a change has been made
window.dispatchEvent(new Event('mediaManager.history.point'));
canvas = null;
};
const addListeners = image => {
// The listeners
formElements.resizeWidth.addEventListener('change', ({
target
}) => {
resize(parseInt(target.value, 10), parseInt(target.value, 10) / (image.width / image.height), image);
});
formElements.resizeHeight.addEventListener('change', ({
target
}) => {
resize(parseInt(target.value, 10) * (image.width / image.height), parseInt(target.value, 10), image);
});
};
const initResize = image => {
// Update the input boxes
formElements.resizeWidth.value = image.naturalWidth;
formElements.resizeHeight.value = image.naturalHeight;
if (!activated) {
activated = true;
addListeners(image);
}
};
window.addEventListener('media-manager-edit-init', () => {
// Get the form elements
formElements = {
resizeWidth: document.getElementById('jform_resize_width'),
resizeHeight: document.getElementById('jform_resize_height'),
resizeQuality: document.getElementById('jform_resize_quality')
};
// Register the Events
Joomla.MediaManager.Edit.plugins.resize = {
Activate(image) {
return new Promise((resolve /* , reject */) => {
// Initialize
initResize(image);
resolve();
});
},
Deactivate( /* image */
) {
return new Promise((resolve /* , reject */) => {
resolve();
});
}
};
}, {
once: true
});