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+/**
+ * --------------------------------------------------------------------------
+ * Bootstrap (v5.2.3): util/sanitizer.js
+ * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
+ * --------------------------------------------------------------------------
+ */
+
+const uriAttributes = new Set([
+ 'background',
+ 'cite',
+ 'href',
+ 'itemtype',
+ 'longdesc',
+ 'poster',
+ 'src',
+ 'xlink:href'
+])
+
+const ARIA_ATTRIBUTE_PATTERN = /^aria-[\w-]*$/i
+
+/**
+ * A pattern that recognizes a commonly useful subset of URLs that are safe.
+ *
+ * Shout-out to Angular https://github.com/angular/angular/blob/12.2.x/packages/core/src/sanitization/url_sanitizer.ts
+ */
+const SAFE_URL_PATTERN = /^(?:(?:https?|mailto|ftp|tel|file|sms):|[^#&/:?]*(?:[#/?]|$))/i
+
+/**
+ * A pattern that matches safe data URLs. Only matches image, video and audio types.
+ *
+ * Shout-out to Angular https://github.com/angular/angular/blob/12.2.x/packages/core/src/sanitization/url_sanitizer.ts
+ */
+const DATA_URL_PATTERN = /^data:(?:image\/(?:bmp|gif|jpeg|jpg|png|tiff|webp)|video\/(?:mpeg|mp4|ogg|webm)|audio\/(?:mp3|oga|ogg|opus));base64,[\d+/a-z]+=*$/i
+
+const allowedAttribute = (attribute, allowedAttributeList) => {
+ const attributeName = attribute.nodeName.toLowerCase()
+
+ if (allowedAttributeList.includes(attributeName)) {
+ if (uriAttributes.has(attributeName)) {
+ return Boolean(SAFE_URL_PATTERN.test(attribute.nodeValue) || DATA_URL_PATTERN.test(attribute.nodeValue))
+ }
+
+ return true
+ }
+
+ // Check if a regular expression validates the attribute.
+ return allowedAttributeList.filter(attributeRegex => attributeRegex instanceof RegExp)
+ .some(regex => regex.test(attributeName))
+}
+
+export const DefaultAllowlist = {
+ // Global attributes allowed on any supplied element below.
+ '*': ['class', 'dir', 'id', 'lang', 'role', ARIA_ATTRIBUTE_PATTERN],
+ a: ['target', 'href', 'title', 'rel'],
+ area: [],
+ b: [],
+ br: [],
+ col: [],
+ code: [],
+ div: [],
+ em: [],
+ hr: [],
+ h1: [],
+ h2: [],
+ h3: [],
+ h4: [],
+ h5: [],
+ h6: [],
+ i: [],
+ img: ['src', 'srcset', 'alt', 'title', 'width', 'height'],
+ li: [],
+ ol: [],
+ p: [],
+ pre: [],
+ s: [],
+ small: [],
+ span: [],
+ sub: [],
+ sup: [],
+ strong: [],
+ u: [],
+ ul: []
+}
+
+export function sanitizeHtml(unsafeHtml, allowList, sanitizeFunction) {
+ if (!unsafeHtml.length) {
+ return unsafeHtml
+ }
+
+ if (sanitizeFunction && typeof sanitizeFunction === 'function') {
+ return sanitizeFunction(unsafeHtml)
+ }
+
+ const domParser = new window.DOMParser()
+ const createdDocument = domParser.parseFromString(unsafeHtml, 'text/html')
+ const elements = [].concat(...createdDocument.body.querySelectorAll('*'))
+
+ for (const element of elements) {
+ const elementName = element.nodeName.toLowerCase()
+
+ if (!Object.keys(allowList).includes(elementName)) {
+ element.remove()
+
+ continue
+ }
+
+ const attributeList = [].concat(...element.attributes)
+ const allowedAttributes = [].concat(allowList['*'] || [], allowList[elementName] || [])
+
+ for (const attribute of attributeList) {
+ if (!allowedAttribute(attribute, allowedAttributes)) {
+ element.removeAttribute(attribute.nodeName)
+ }
+ }
+ }
+
+ return createdDocument.body.innerHTML
+}