Image link support

markdown.js

@@ -53,7 +53,7 @@ class Symbol {
   static canParse(line) {
     throw new Error("Not implemented");
   }
-  static create(lineFeed) {
+  static create(lineFeed, assetDirectory) {
     throw new Error("Not implemented");
   }
   render() {
@@ -217,6 +217,62 @@ class Link extends Symbol {
   }
 }
 
+class ImageLink extends Symbol {
+  /**
+   * @type {RegExp}
+   */
+  static canParseRegExp = new RegExp(/^!\[.*\]\(.*\)/);
+  /**
+   * @type {RegExp}
+   */
+  static textAndLinkRegExp = new RegExp(/!\[(?<text>.*)\]\((?<link>.*)\)/);
+  /**
+   * @type {string}
+   */
+  static assetDirectoryToken = "@asset/";
+  /**
+   * @type {string}
+   */
+  alt = "";
+  /**
+   * @type {string}
+   */
+  link = "";
+  /**
+   *
+   * @param {string} line
+   * @returns {boolean}
+   */
+  static canParse(line) {
+    return ImageLink.canParseRegExp.test(line.trim());
+  }
+
+  /**
+   *
+   * @param {LineFeed} lineFeed
+   * @returns {Symbol}
+   */
+  static create(lineFeed, assetDirectory) {
+    const instance = new ImageLink();
+    const line = lineFeed.claim().trim();
+    const [linkLine, rest] = extractTokenAndRest(
+      ImageLink.textAndLinkRegExp,
+      line
+    );
+    lineFeed.push(rest);
+    const { text, link } =
+      ImageLink.textAndLinkRegExp.exec(linkLine)?.groups ?? {};
+    instance.link =
+      link.replace(ImageLink.assetDirectoryToken, assetDirectory) ?? "";
+    instance.alt = text ?? "";
+    return instance;
+  }
+
+  render() {
+    return `<img src="${this.link}" alt="${this.alt}"/>`;
+  }
+}
+
 class Italic extends Symbol {
   /**
    * @type {string}
@@ -525,32 +581,48 @@ const getAmountOfTokenInBeginningOfFile = (token, string) => {
   }
 };
 
+/**
+ * @type {Symbol[]}
+ */
 const Factories = [
   Heading,
   UnorderedListItem,
   OrderedListItem,
   Bold,
   Italic,
+  ImageLink,
   Link,
   MultiLineCode,
   SingleLineCode,
   CatchAll,
 ];
 
-export const toHtml = (markdown) => {
-  const symbols = toSymbols(markdown);
+/**
+ *
+ * @param {string} markdown
+ * @param {string} assetDirectory
+ * @returns {string}
+ */
+export const toHtml = (markdown, assetDirectory) => {
+  const symbols = toSymbols(markdown, assetDirectory);
   const html = symbols.map((s) => s.render()).join("");
   return `<div>${html}</div>`;
 };
 
-const toSymbols = (markdown) => {
+/**
+ *
+ * @param {string} markdown
+ * @param {string} assetDirectory
+ * @returns {Symbol[]}
+ */
+const toSymbols = (markdown, assetDirectory) => {
   const lineFeed = new LineFeed(markdown);
   const symbols = [];
 
   while (!lineFeed.isEmpty()) {
     const line = lineFeed.peek();
     const factory = Factories.find((factory) => factory.canParse(line));
-    const symbol = factory.create(lineFeed);
+    const symbol = factory.create(lineFeed, assetDirectory);
     symbols.push(symbol);
   }