chore: added javascript to check correct file size limitations for form

Author: jdalsem

views/default/forms/forms/submit_files.mjs

@@ -1,2 +1,54 @@
 import 'jquery';
+import 'input/file'; // make sure core file init is registered first
 import i18n from 'elgg/i18n';
+
+function updateFileLimits() {
+	var $form = $(this).parents('.elgg-form-forms-submit').eq(0);
+	var $all_files = $form.find('input[type=file]');
+	var form_max_size = $form.data().maxFileSize;
+	var running_total = 0;
+
+	$all_files.each(function(index, file) {
+		if (file.files.length === 0) {
+			return;
+		}
+
+		running_total += file.files[0].size;
+	});
+
+	var total_bytes_left = form_max_size - running_total;
+
+	$all_files.each(function(index, file) {
+		var $file = $(file);
+		var max_size = $file.data().originalMaxSize;
+
+		var bytes_left = total_bytes_left;
+		if (file.files.length > 0) {
+			bytes_left += file.files[0].size;
+		}
+
+		max_size = Math.min(max_size, bytes_left);
+
+		var readable_max_size = formatBytes(max_size);
+		$file.data().maxSize = max_size;
+		$file.data().maxSizeMessage = i18n.echo('upload:error:ini_size') + ' ' + i18n.echo('input:file:upload_limit', [readable_max_size]);
+		$file.parent().next('.elgg-field-help').find('.elgg-input-file-size-helper').text(i18n.echo('input:file:upload_limit', [readable_max_size]))
+	});
+}
+
+function formatBytes(size) {
+	if (size < 0) {
+		return size;
+	}
+
+	if (size === 0) {
+		return '0 B';
+	}
+
+	var base = Math.log(size) / Math.log(1024);
+	var suffixes = ['B', 'kB', 'MB', 'GB', 'TB'];
+
+	return Math.round(Math.pow(1024, base - Math.floor(base)), 2) + ' ' + suffixes[Math.floor(base)];
+}
+
+$(document).on('change', '.elgg-form-forms-submit input[type=file]', updateFileLimits);