Formalize "Decorated components API"

ts/editable/decorated.ts

@@ -0,0 +1,45 @@
+// Copyright: Ankitects Pty Ltd and contributors
+// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+/**
+ * decorated elements know three states:
+ * - stored, which is stored in the DB, e.g. `\(\alpha + \beta\)`
+ * - undecorated, which is displayed to the user in Codable, e.g. `<anki-mathjax>\alpha + \beta</anki-mathjax>`
+ * - decorated, which is displayed to the user in Editable, e.g. `<anki-mathjax data-mathjax="\alpha + \beta"><img src="data:..."></anki-mathjax>`
+ */
+
+export interface DecoratedElement extends HTMLElement {
+    /**
+     * Transforms itself from undecorated to decorated state.
+     * Should be called in connectedCallback.
+     */
+    decorate(): void;
+    /**
+     * Transforms itself from decorated to undecorated state.
+     */
+    undecorate(): void;
+}
+
+export interface DecoratedElementConstructor extends CustomElementConstructor {
+    prototype: DecoratedElement;
+    tagName: string;
+    /**
+     * Transforms elements in input HTML from undecorated to stored state.
+     */
+    toStored(undecorated: string): string;
+    /**
+     * Transforms elements in input HTML from stored to undecorated state.
+     */
+    toUndecorated(stored: string): string;
+}
+
+class DefineArray extends Array {
+    push(...elements: DecoratedElementConstructor[]) {
+        for (const element of elements) {
+            customElements.define(element.tagName, element);
+        }
+        return super.push(...elements);
+    }
+}
+
+export const decoratedComponents: DecoratedElementConstructor[] = new DefineArray();

ts/editable/editable.ts

@@ -1,6 +1,8 @@
 // Copyright: Ankitects Pty Ltd and contributors
 // License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
+import type { DecoratedElement } from "./decorated";
+import { decoratedComponents } from "./decorated";
 import { bridgeCommand } from "lib/bridgecommand";
 import { elementIsBlock, getBlockElement } from "lib/dom";
 // import { inCodable } from "./toolbar";
@@ -25,13 +27,6 @@ function containsInlineContent(element: Element): boolean {
     return true;
 }
 
-interface DecoratedElement extends HTMLElement {
-    decorate(): void;
-    undecorate(): void;
-}
-
-const decoratedTags = ["anki-mathjax"];
-
 export class Editable extends HTMLElement {
     set fieldHTML(content: string) {
         this.innerHTML = content;
@@ -44,8 +39,8 @@ export class Editable extends HTMLElement {
     get fieldHTML(): string {
         const clone = this.cloneNode(true) as Element;
 
-        for (const component of decoratedTags) {
-            for (const element of clone.getElementsByTagName(component)) {
+        for (const component of decoratedComponents) {
+            for (const element of clone.getElementsByTagName(component.tagName)) {
                 (element as DecoratedElement).undecorate();
             }
         }

ts/editable/mathjax-component.ts

@@ -1,4 +1,7 @@
 import "mathjax/es5/tex-svg-full";
+
+import type { DecoratedElement, DecoratedElementConstructor } from "./decorated";
+import { decoratedComponents } from "./decorated";
 import { nodeIsElement } from "lib/dom";
 
 import Mathjax_svelte from "./Mathjax.svelte";
@@ -37,9 +40,44 @@ function moveNodesInsertedBeforeEndToAfterEnd(element: Element): () => void {
     return () => observer.disconnect();
 }
 
-class Mathjax extends HTMLElement {
-    block: boolean = false;
-    disconnect: () => void = () => {};
+const mathjaxTagPattern =
+    /<anki-mathjax(?:[^>]*?block="(.*?)")?[^>]*?>(.*?)<\/anki-mathjax>/gsu;
+
+const mathjaxBlockDelimiterPattern = /\\\[(.*?)\\\]/gsu;
+const mathjaxInlineDelimiterPattern = /\\\((.*?)\\\)/gsu;
+
+export const Mathjax: DecoratedElementConstructor = class Mathjax
+    extends HTMLElement
+    implements DecoratedElement
+{
+    static tagName = "anki-mathjax";
+
+    static toStored(undecorated: string): string {
+        return undecorated.replace(
+            mathjaxTagPattern,
+            (_match: string, block: string | undefined, text: string) => {
+                return typeof block === "string" && block !== "false"
+                    ? `\\[${text}\\]`
+                    : `\\(${text}\\)`;
+            }
+        );
+    }
+
+    static toUndecorated(stored: string): string {
+        return stored
+            .replace(
+                mathjaxBlockDelimiterPattern,
+                (_match: string, text: string) =>
+                    `<anki-mathjax block="true">${text}</anki-mathjax>`
+            )
+            .replace(
+                mathjaxInlineDelimiterPattern,
+                (_match: string, text: string) => `<anki-mathjax>${text}</anki-mathjax>`
+            );
+    }
+
+    block = false;
+    disconnect: () => void = () => {/* noop */};
 
     constructor() {
         super();
@@ -82,40 +120,6 @@ class Mathjax extends HTMLElement {
             this.removeAttribute("block");
         }
     }
-}
+};
 
-customElements.define("anki-mathjax", Mathjax);
-
-const mathjaxTagPattern =
-    /<anki-mathjax(?:[^>]*?block="(.*?)")?[^>]*?>(.*?)<\/anki-mathjax>/gsu;
-
-export function toMathjaxDelimiters(html: string): string {
-    return html.replace(
-        mathjaxTagPattern,
-        (_match: string, block: string | undefined, text: string) => {
-            console.log("delim", _match, block, "text", text);
-            return typeof block === "string" && block !== "false"
-                ? `\\[${text}\\]`
-                : `\\(${text}\\)`;
-        }
-    );
-}
-
-const mathjaxBlockDelimiterPattern = /\\\[(.*?)\\\]/gsu;
-const mathjaxInlineDelimiterPattern = /\\\((.*?)\\\)/gsu;
-
-export function toMathjaxTags(html: string): string {
-    return html
-        .replace(
-            mathjaxBlockDelimiterPattern,
-            (_match: string, text: string) => (
-                console.log(text), `<anki-mathjax block="true">${text}</anki-mathjax>`
-            )
-        )
-        .replace(
-            mathjaxInlineDelimiterPattern,
-            (_match: string, text: string) => (
-                console.log(text), `<anki-mathjax>${text}</anki-mathjax>`
-            )
-        );
-}
+decoratedComponents.push(Mathjax);

ts/editor/editing-area.ts

@@ -17,7 +17,7 @@ import { bridgeCommand } from "./lib";
 import { onInput, onKey, onKeyUp } from "./input-handlers";
 import { onFocus, onBlur } from "./focus-handlers";
 import { nightModeKey } from "components/context-keys";
-import { toMathjaxTags, toMathjaxDelimiters } from "editable/mathjax-component";
+import { decoratedComponents } from "editable/decorated";
 
 function onCutOrCopy(): void {
     bridgeCommand("cutOrCopy");
@@ -93,13 +93,23 @@ export class EditingArea extends HTMLDivElement {
     }
 
     set fieldHTML(content: string) {
-        this.imageHandle.then(
-            () => (this.activeInput.fieldHTML = toMathjaxTags(content))
-        );
+        this.imageHandle.then(() => {
+            let result = content;
+            for (const component of decoratedComponents) {
+                result = component.toUndecorated(result);
+            }
+
+            this.activeInput.fieldHTML = result;
+        });
     }
 
     get fieldHTML(): string {
-        return toMathjaxDelimiters(this.activeInput.fieldHTML);
+        let result = this.activeInput.fieldHTML;
+        for (const component of decoratedComponents) {
+            result = component.toStored(result);
+        }
+
+        return result;
     }
 
     connectedCallback(): void {