Mathjax editor improvements (#1502)

* Remove unnecessary stopPropagation of mathjax-overlay events

* Use CodeMirror component for MathjaxHandle

* Refactor ResizeObserver code in MathjaxHandle

* Wrap setRange in CodeMirror in try/catch

* Add Mathjax Editor bottom margin

* Add custom Enter and Shift+Enter shortcuts for the MathjaxHandle

* Format

* Move placeCaretAfter to domlib

* Move focus back to field after editing Mathjax

* Put Cursor after Mathjax after accepting

* Add delete button for Mathjax

* Change border color of mathjax menu

* Refactor into MathjaxMenu

* Put caretKeyword in variable

* Use one ResizeObserver for all Mathjax images

* Add minmimum width for Mathjax editor

* is still smaller than minimal window width

* Add bazel directories to .prettierignore and format from root

* exclude ftl/usage (dae)

the json files that live there are output from our tooling, and
formatting them means an extra step each time we want to update them

also exclude .mypy_cache, which is output by scripts/mypy*

* minor ftl tweak: newline -> new line  (dae)

.prettierignore

@@ -1,2 +1,6 @@
 licenses.json
 vendor
+node_modules
+bazel-*
+ftl/usage
+.mypy_cache

.prettierrc

@@ -2,5 +2,5 @@
     "trailingComma": "all",
     "printWidth": 88,
     "tabWidth": 4,
-    "semi": true,
+    "semi": true
 }

ftl/core/editing.ftl

@@ -30,6 +30,7 @@ editing-latex-math-env = LaTeX math env.
 editing-mathjax-block = MathJax block
 editing-mathjax-chemistry = MathJax chemistry
 editing-mathjax-inline = MathJax inline
+editing-mathjax-placeholder = Press { $accept } to accept, { $newline } for new line.
 editing-media = Media
 editing-ordered-list = Ordered list
 editing-outdent = Decrease indent

rslib/src/notetype/styling.css

@@ -1,7 +1,7 @@
 .card {
-  font-family: arial;
-  font-size: 20px;
-  text-align: center;
-  color: black;
-  background-color: white;
+    font-family: arial;
+    font-size: 20px;
+    text-align: center;
+    color: black;
+    background-color: white;
 }

sass/breakpoints.scss

@@ -3,14 +3,7 @@
 @use "sass:list";
 @use "sass:map";
 
-$bps: (
-    "xs",
-    "sm",
-    "md",
-    "lg",
-    "xl",
-    "xxl",
-);
+$bps: ("xs", "sm", "md", "lg", "xl", "xxl");
 
 $breakpoints: (
     list.nth($bps, 2): 576px,
@@ -28,10 +21,10 @@ $breakpoints: (
     } @else {
         @content;
     }
-};
+}
 
 @mixin with-breakpoints($prefix, $dict) {
-    @each $property, $values in $dict  {
+    @each $property, $values in $dict {
         @each $bp, $value in $values {
             @if map.get($breakpoints, $bp) {
                 @media (min-width: map.get($breakpoints, $bp)) {
@@ -46,7 +39,7 @@ $breakpoints: (
             }
         }
     }
-};
+}
 
 @function breakpoints-upto($upto) {
     $result: ();
@@ -66,14 +59,14 @@ $breakpoints: (
     $result: ();
 
     @each $bp in breakpoints-upto($upto) {
-        $result: list.append($result, ".#{$prefix}-#{$bp}", $separator: comma)
+        $result: list.append($result, ".#{$prefix}-#{$bp}", $separator: comma);
     }
 
     @return $result;
 }
 
 @mixin with-breakpoints-upto($prefix, $dict) {
-    @each $property, $values in $dict  {
+    @each $property, $values in $dict {
         @each $bp, $value in $values {
             $selector: breakpoint-selector-upto($prefix, $bp);
 
@@ -90,4 +83,4 @@ $breakpoints: (
             }
         }
     }
-};
+} ;

ts/domlib/place-caret.ts

@@ -0,0 +1,14 @@
+// Copyright: Ankitects Pty Ltd and contributors
+// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+import { getSelection } from "../lib/cross-browser";
+
+export function placeCaretAfter(node: Node): void {
+    const range = new Range();
+    range.setStartAfter(node);
+    range.collapse(false);
+
+    const selection = getSelection(node)!;
+    selection.removeAllRanges();
+    selection.addRange(range);
+}

ts/editable/ContentEditable.svelte

@@ -6,7 +6,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     import type { Writable } from "svelte/store";
     import { updateAllState } from "../components/WithState.svelte";
     import { saveSelection, restoreSelection } from "../domlib/location";
-    import { on } from "../lib/events";
+    import { on, preventDefault } from "../lib/events";
     import { registerShortcut } from "../lib/shortcuts";
 
     export let nodes: Writable<DocumentFragment>;
@@ -18,29 +18,31 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
     export let inputManager: (editable: HTMLElement) => void;
 
+    let removeOnFocus: () => void;
+    let removeOnPointerdown: () => void;
+
+    function onBlur(): void {
+        const location = saveSelection(editable);
+
+        removeOnFocus = on(
+            editable,
+            "focus",
+            () => {
+                if (location) {
+                    restoreSelection(editable, location);
+                }
+            },
+            { once: true },
+        );
+
+        removeOnPointerdown = on(editable, "pointerdown", () => removeOnFocus?.(), {
+            once: true,
+        });
+    }
+
     /* must execute before DOMMirror */
     function saveLocation(editable: HTMLElement) {
-        let removeOnFocus: () => void;
-        let removeOnPointerdown: () => void;
-
-        const removeOnBlur = on(editable, "blur", () => {
-            const location = saveSelection(editable);
-
-            removeOnFocus = on(
-                editable,
-                "focus",
-                () => {
-                    if (location) {
-                        restoreSelection(editable, location);
-                    }
-                },
-                { once: true },
-            );
-
-            removeOnPointerdown = on(editable, "pointerdown", () => removeOnFocus?.(), {
-                once: true,
-            });
-        });
+        const removeOnBlur = on(editable, "blur", onBlur);
 
         return {
             destroy() {
@@ -54,10 +56,14 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     let editable: HTMLElement;
 
     $: if (editable) {
-        registerShortcut((event) => event.preventDefault(), "Control+B", editable);
-        registerShortcut((event) => event.preventDefault(), "Control+U", editable);
-        registerShortcut((event) => event.preventDefault(), "Control+I", editable);
-        registerShortcut((event) => event.preventDefault(), "Control+R", editable);
+        for (const keyCombination of [
+            "Control+B",
+            "Control+U",
+            "Control+I",
+            "Control+R",
+        ]) {
+            registerShortcut(preventDefault, keyCombination, editable);
+        }
     }
 </script>
 

ts/editable/Mathjax.svelte

@@ -2,67 +2,85 @@
 Copyright: Ankitects Pty Ltd and contributors
 License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 -->
-<script lang="ts">
-    import { onMount, onDestroy, getContext, tick } from "svelte";
-    import { nightModeKey } from "../components/context-keys";
-    import { convertMathjax } from "./mathjax";
+<script context="module" lang="ts">
+    import type { Writable } from "svelte/store";
 
-    export let mathjax: string;
-    export let block: boolean;
-    export let autofocus = false;
+    const imageToHeightMap = new Map<string, Writable<number>>();
+    const observer = new ResizeObserver((entries: ResizeObserverEntry[]) => {
+        for (const entry of entries) {
+            const image = entry.target as HTMLImageElement;
+            const store = imageToHeightMap.get(image.dataset.uuid!)!;
+            store.set(entry.contentRect.height);
 
-    /* have fixed fontSize for normal */
-    export const fontSize: number = 20;
-
-    const nightMode = getContext<boolean>(nightModeKey);
-
-    $: [converted, title] = convertMathjax(mathjax, nightMode, fontSize);
-    $: empty = title === "MathJax";
-
-    let encoded: string;
-    let imageHeight: number;
-
-    $: encoded = encodeURIComponent(converted);
-
-    let image: HTMLImageElement;
-
-    const observer = new ResizeObserver(async () => {
-        imageHeight = image.getBoundingClientRect().height;
-        await tick();
-        setTimeout(() => image.dispatchEvent(new Event("resize")));
-    });
-
-    onMount(() => {
-        observer.observe(image);
-
-        if (autofocus) {
-            // This should trigger a focusing of the Mathjax Handle
-            const focusEvent = new CustomEvent("focusmathjax", {
-                detail: image,
-                bubbles: true,
-                composed: true,
-            });
-
-            image.dispatchEvent(focusEvent);
+            setTimeout(() => entry.target.dispatchEvent(new Event("resize")));
         }
     });
-
-    onDestroy(() => {
-        observer.unobserve(image);
-        observer.disconnect();
-    });
+</script>
+
+<script lang="ts">
+    import { onDestroy, getContext } from "svelte";
+    import { nightModeKey } from "../components/context-keys";
+    import { convertMathjax } from "./mathjax";
+    import { randomUUID } from "../lib/uuid";
+    import { writable } from "svelte/store";
+
+    export let mathjax: string;
+    export let block: boolean;
+
+    export let autofocus = false;
+    export let fontSize = 20;
+
+    const nightMode = getContext<boolean>(nightModeKey);
+    $: [converted, title] = convertMathjax(mathjax, nightMode, fontSize);
+    $: empty = title === "MathJax";
+    $: encoded = encodeURIComponent(converted);
+
+    const uuid = randomUUID();
+    const imageHeight = writable(0);
+    imageToHeightMap.set(uuid, imageHeight);
+
+    $: verticalCenter = -$imageHeight / 2 + fontSize / 4;
+
+    function maybeAutofocus(image: Element): void {
+        if (!autofocus) {
+            return;
+        }
+
+        // This should trigger a focusing of the Mathjax Handle
+        const focusEvent = new CustomEvent("focusmathjax", {
+            detail: image,
+            bubbles: true,
+            composed: true,
+        });
+
+        image.dispatchEvent(focusEvent);
+    }
+
+    function observe(image: Element) {
+        observer.observe(image);
+
+        return {
+            destroy() {
+                observer.unobserve(image);
+            },
+        };
+    }
+
+    onDestroy(() => imageToHeightMap.delete(uuid));
 </script>
 
 <img
-    bind:this={image}
     src="data:image/svg+xml,{encoded}"
     class:block
     class:empty
-    style="--vertical-center: {-imageHeight / 2 + fontSize / 4}px;"
+    style="--vertical-center: {verticalCenter}px;"
     alt="Mathjax"
     {title}
     data-anki="mathjax"
+    data-uuid={uuid}
     on:dragstart|preventDefault
+    use:maybeAutofocus
+    use:observe
 />
 
 <style lang="scss">
@@ -76,7 +94,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
     .block {
         display: block;
-        margin: auto;
+        margin: 1rem auto;
     }
 
     .empty {

ts/editable/mathjax-element.ts

@@ -9,6 +9,8 @@ import "mathjax/es5/tex-svg-full";
 
 import type { DecoratedElement, DecoratedElementConstructor } from "./decorated";
 import { nodeIsElement } from "../lib/dom";
+import { noop } from "../lib/functional";
+import { placeCaretAfter } from "../domlib/place-caret";
 import { nightModeKey } from "../components/context-keys";
 
 import Mathjax_svelte from "./Mathjax.svelte";
@@ -35,16 +37,6 @@ function moveNodeOutOfElement(
     return referenceNode;
 }
 
-function placeCaretAfter(node: Node): void {
-    const range = new Range();
-    range.setStartAfter(node);
-    range.collapse(false);
-
-    const selection = document.getSelection()!;
-    selection.removeAllRanges();
-    selection.addRange(range);
-}
-
 function moveNodesInsertedOutside(element: Element, allowedChild: Node): () => void {
     const observer = new MutationObserver(() => {
         if (element.childNodes.length === 1) {
@@ -123,9 +115,7 @@ export const Mathjax: DecoratedElementConstructor = class Mathjax
     }
 
     block = false;
-    disconnect: () => void = () => {
-        /* noop */
-    };
+    disconnect = noop;
     component?: Mathjax_svelte;
 
     static get observedAttributes(): string[] {

ts/editor/CodeMirror.svelte

@@ -11,13 +11,14 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 </script>
 
 <script lang="ts">
-    import { createEventDispatcher, getContext } from "svelte";
+    import { createEventDispatcher, getContext, onMount } from "svelte";
     import type { Writable } from "svelte/store";
     import storeSubscribe from "../sveltelib/store-subscribe";
     import { directionKey } from "../lib/context-keys";
 
     export let configuration: CodeMirror.EditorConfiguration;
     export let code: Writable<string>;
+    export let autofocus = false;
 
     const direction = getContext<Writable<"ltr" | "rtl">>(directionKey);
     const defaultConfiguration = {
@@ -52,13 +53,19 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
         });
         codeMirror.on("focus", () => {
             if (ranges) {
-                codeMirror.setSelections(ranges);
+                try {
+                    codeMirror.setSelections(ranges);
+                } catch {
+                    ranges = null;
+                }
             }
             unsubscribe();
+            dispatch("focus");
         });
         codeMirror.on("blur", () => {
             ranges = codeMirror.listSelections();
             subscribe();
+            dispatch("blur");
         });
 
         subscribe();
@@ -70,6 +77,13 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
             editor: { get: () => codeMirror },
         },
     ) as CodeMirrorAPI;
+
+    onMount(() => {
+        if (autofocus) {
+            codeMirror.focus();
+            codeMirror.setCursor(codeMirror.lineCount(), 0);
+        }
+    });
 </script>
 
 <div class="code-mirror">
@@ -79,7 +93,6 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 <style lang="scss">
     .code-mirror :global(.CodeMirror) {
         height: auto;
-        border-radius: 0 0 5px 5px;
         padding: 6px 0;
     }
 </style>

ts/editor/PlainTextInput.svelte

@@ -16,7 +16,6 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 <script lang="ts">
     import CodeMirror from "./CodeMirror.svelte";
     import type { CodeMirrorAPI } from "./CodeMirror.svelte";
-
     import { tick, onMount } from "svelte";
     import { writable } from "svelte/store";
     import { getDecoratedElements } from "./DecoratedElements.svelte";
@@ -143,7 +142,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     });
 </script>
 
-<div class:hidden on:focusin on:focusout>
+<div class="plain-text-input" class:hidden on:focusin on:focusout>
     <CodeMirror
         {configuration}
         {code}
@@ -153,6 +152,10 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 </div>
 
 <style lang="scss">
+    .plain-text-input :global(.CodeMirror) {
+        border-radius: 0 0 5px 5px;
+    }
+
     .hidden {
         display: none;
     }

ts/editor/RichTextInput.svelte

@@ -50,6 +50,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     import { promiseWithResolver } from "../lib/promise";
     import { bridgeCommand } from "../lib/bridgecommand";
     import { wrapInternal } from "../lib/wrap";
+    import { on } from "../lib/events";
     import { nodeStore } from "../sveltelib/node-store";
     import type { DecoratedElement } from "../editable/decorated";
     import { nightModeKey } from "../components/context-keys";
@@ -142,16 +143,16 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
             bridgeCommand("cutOrCopy");
         }
 
-        richTextInput.addEventListener("paste", onPaste);
-        richTextInput.addEventListener("copy", onCutOrCopy);
-        richTextInput.addEventListener("cut", onCutOrCopy);
+        const removePaste = on(richTextInput, "paste", onPaste);
+        const removeCopy = on(richTextInput, "copy", onCutOrCopy);
+        const removeCut = on(richTextInput, "cut", onCutOrCopy);
         richTextResolve(richTextInput);
 
         return {
             destroy() {
-                richTextInput.removeEventListener("paste", onPaste);
-                richTextInput.removeEventListener("copy", onCutOrCopy);
-                richTextInput.removeEventListener("cut", onCutOrCopy);
+                removePaste();
+                removeCopy();
+                removeCut();
             },
         };
     }

ts/editor/code-mirror.ts

@@ -11,8 +11,9 @@ import "codemirror/mode/stex/stex";
 import "codemirror/addon/fold/foldcode";
 import "codemirror/addon/fold/foldgutter";
 import "codemirror/addon/fold/xml-fold";
-import "codemirror/addon/edit/matchtags.js";
-import "codemirror/addon/edit/closetag.js";
+import "codemirror/addon/edit/matchtags";
+import "codemirror/addon/edit/closetag";
+import "codemirror/addon/display/placeholder";
 
 export { CodeMirror };
 

ts/editor/mathjax-overlay/Editor.svelte

@@ -1,81 +0,0 @@
-<!--
-Copyright: Ankitects Pty Ltd and contributors
-License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
--->
-<script lang="ts">
-    import { onMount, createEventDispatcher } from "svelte";
-    import { ChangeTimer } from "../change-timer";
-    import { CodeMirror, latex, baseOptions } from "../code-mirror";
-
-    export let initialValue: string;
-
-    const codeMirrorOptions = {
-        mode: latex,
-        ...baseOptions,
-    };
-
-    let codeMirror: CodeMirror.EditorFromTextArea;
-    const changeTimer = new ChangeTimer();
-    const dispatch = createEventDispatcher();
-
-    function onInput() {
-        dispatch("update", { mathjax: codeMirror.getValue() });
-
-        /* changeTimer.schedule( */
-        /*     () => dispatch("update", { mathjax: codeMirror.getValue() }), */
-        /*     400 */
-        /* ); */
-    }
-
-    function onBlur() {
-        changeTimer.fireImmediately();
-        dispatch("codemirrorblur");
-    }
-
-    function openCodemirror(textarea: HTMLTextAreaElement): void {
-        codeMirror = CodeMirror.fromTextArea(textarea, codeMirrorOptions);
-        codeMirror.on("change", onInput);
-        codeMirror.on("blur", onBlur);
-    }
-
-    let textarea: HTMLTextAreaElement;
-
-    onMount(() => {
-        codeMirror.focus();
-        codeMirror.setCursor(codeMirror.lineCount(), 0);
-
-        const codeMirrorElement = textarea.nextElementSibling!;
-        codeMirrorElement.classList.add("mathjax-editor");
-    });
-</script>
-
-<div
-    on:click|stopPropagation
-    on:focus|stopPropagation
-    on:focusin|stopPropagation
-    on:keydown|stopPropagation
-    on:keyup|stopPropagation
-    on:mousedown|preventDefault|stopPropagation
-    on:mouseup|stopPropagation
-    on:paste|stopPropagation
->
-    <!-- TODO no focusin for now, as EditingArea will defer to Editable/Codable -->
-    <textarea
-        bind:this={textarea}
-        value={initialValue}
-        on:input={onInput}
-        use:openCodemirror
-    />
-</div>
-
-<style lang="scss">
-    div :global(.mathjax-editor) {
-        border-radius: 0;
-        border-width: 0 1px;
-        border-color: var(--medium-border);
-
-        height: auto;
-        border-radius: 0 0 5px 5px;
-        padding: 6px 0;
-    }
-</style>

ts/editor/mathjax-overlay/InlineBlock.svelte

@@ -1,36 +0,0 @@
-<!--
-Copyright: Ankitects Pty Ltd and contributors
-License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
--->
-<script lang="ts">
-    import ButtonGroup from "../../components/ButtonGroup.svelte";
-    import ButtonGroupItem from "../../components/ButtonGroupItem.svelte";
-    import IconButton from "../../components/IconButton.svelte";
-
-    import * as tr from "../../lib/ftl";
-    import { inlineIcon, blockIcon } from "./icons";
-
-    export let activeImage: HTMLImageElement;
-
-    $: mathjaxElement = activeImage.parentElement!;
-</script>
-
-<ButtonGroup size={1.6} wrap={false}>
-    <ButtonGroupItem>
-        <IconButton
-            tooltip={tr.editingMathjaxInline()}
-            active={activeImage.getAttribute("block") === "true"}
-            on:click={() => mathjaxElement.setAttribute("block", "false")}
-            on:click>{@html inlineIcon}</IconButton
-        >
-    </ButtonGroupItem>
-
-    <ButtonGroupItem>
-        <IconButton
-            tooltip={tr.editingMathjaxBlock()}
-            active={activeImage.getAttribute("block") === "false"}
-            on:click={() => mathjaxElement.setAttribute("block", "true")}
-            on:click>{@html blockIcon}</IconButton
-        >
-    </ButtonGroupItem>
-</ButtonGroup>

ts/editor/mathjax-overlay/MathjaxButtons.svelte

@@ -0,0 +1,54 @@
+<!--
+Copyright: Ankitects Pty Ltd and contributors
+License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+-->
+<script lang="ts">
+    import ButtonToolbar from "../../components/ButtonToolbar.svelte";
+    import Item from "../../components/Item.svelte";
+    import ButtonGroup from "../../components/ButtonGroup.svelte";
+    import ButtonGroupItem from "../../components/ButtonGroupItem.svelte";
+    import IconButton from "../../components/IconButton.svelte";
+    import * as tr from "../../lib/ftl";
+    import { inlineIcon, blockIcon, deleteIcon } from "./icons";
+    import { createEventDispatcher } from "svelte";
+
+    export let activeImage: HTMLImageElement;
+    export let mathjaxElement: HTMLElement;
+
+    const dispatch = createEventDispatcher();
+</script>
+
+<ButtonToolbar size={1.6} wrap={false}>
+    <Item>
+        <ButtonGroup>
+            <ButtonGroupItem>
+                <IconButton
+                    tooltip={tr.editingMathjaxInline()}
+                    active={activeImage.getAttribute("block") === "true"}
+                    on:click={() => mathjaxElement.setAttribute("block", "false")}
+                    on:click>{@html inlineIcon}</IconButton
+                >
+            </ButtonGroupItem>
+
+            <ButtonGroupItem>
+                <IconButton
+                    tooltip={tr.editingMathjaxBlock()}
+                    active={activeImage.getAttribute("block") === "false"}
+                    on:click={() => mathjaxElement.setAttribute("block", "true")}
+                    on:click>{@html blockIcon}</IconButton
+                >
+            </ButtonGroupItem>
+        </ButtonGroup>
+    </Item>
+
+    <Item>
+        <ButtonGroup>
+            <ButtonGroupItem>
+                <IconButton
+                    tooltip={tr.actionsDelete()}
+                    on:click={() => dispatch("delete")}>{@html deleteIcon}</IconButton
+                >
+            </ButtonGroupItem>
+        </ButtonGroup>
+    </Item>
+</ButtonToolbar>

ts/editor/mathjax-overlay/MathjaxEditor.svelte

@@ -0,0 +1,59 @@
+<!--
+Copyright: Ankitects Pty Ltd and contributors
+License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+-->
+<script lang="ts">
+    import CodeMirror from "../CodeMirror.svelte";
+    import type { Writable } from "svelte/store";
+    import { baseOptions, latex } from "../code-mirror";
+    import { getPlatformString } from "../../lib/shortcuts";
+    import { noop } from "../../lib/functional";
+    import * as tr from "../../lib/ftl";
+
+    export let acceptShortcut: string;
+    export let newlineShortcut: string;
+
+    export let code: Writable<string>;
+
+    const configuration = {
+        ...Object.assign({}, baseOptions, {
+            extraKeys: {
+                ...(baseOptions.extraKeys as CodeMirror.KeyMap),
+                [acceptShortcut]: noop,
+                [newlineShortcut]: noop,
+            },
+        }),
+        placeholder: tr.editingMathjaxPlaceholder({
+            accept: getPlatformString(acceptShortcut),
+            newline: getPlatformString(newlineShortcut),
+        }),
+        mode: latex,
+    };
+</script>
+
+<div class="mathjax-editor">
+    <CodeMirror
+        {code}
+        {configuration}
+        on:change={({ detail }) => code.set(detail)}
+        on:blur
+        autofocus
+    />
+</div>
+
+<style lang="scss">
+    .mathjax-editor {
+        :global(.CodeMirror) {
+            max-width: 28rem;
+            min-width: 14rem;
+            margin-bottom: 0.25rem;
+        }
+
+        :global(.CodeMirror-placeholder) {
+            font-family: sans-serif;
+            font-size: 55%;
+            text-align: center;
+            color: var(--slightly-grey-text);
+        }
+    }
+</style>

ts/editor/mathjax-overlay/MathjaxHandle.svelte

@@ -4,35 +4,71 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 -->
 <script lang="ts">
     import WithDropdown from "../../components/WithDropdown.svelte";
-    import ButtonToolbar from "../../components/ButtonToolbar.svelte";
-    import DropdownMenu from "../../components/DropdownMenu.svelte";
-    import Item from "../../components/Item.svelte";
-
-    import HandleSelection from "../HandleSelection.svelte";
-    import HandleBackground from "../HandleBackground.svelte";
-    import HandleControl from "../HandleControl.svelte";
-
-    import InlineBlock from "./InlineBlock.svelte";
-    import Editor from "./Editor.svelte";
-
-    import { onMount, tick } from "svelte";
+    import MathjaxMenu from "./MathjaxMenu.svelte";
+    import { onMount, onDestroy, tick } from "svelte";
+    import { writable } from "svelte/store";
     import { getRichTextInput } from "../RichTextInput.svelte";
+    import { placeCaretAfter } from "../../domlib/place-caret";
     import { noop } from "../../lib/functional";
+    import { on } from "../../lib/events";
 
     const { container, api } = getRichTextInput();
 
+    const code = writable("");
+
     let activeImage: HTMLImageElement | null = null;
-    let allow: () => void;
+    let mathjaxElement: HTMLElement | null = null;
+    let allow = noop;
+    let unsubscribe = noop;
+
+    const caretKeyword = "caretAfter";
 
     function showHandle(image: HTMLImageElement): void {
         allow = api.preventResubscription();
+
         activeImage = image;
+        image.setAttribute(caretKeyword, "true");
+        mathjaxElement = activeImage.closest("anki-mathjax")!;
+
+        code.set(mathjaxElement.dataset.mathjax ?? "");
+        unsubscribe = code.subscribe((value: string) => {
+            mathjaxElement!.dataset.mathjax = value;
+        });
     }
 
-    async function maybeShowHandle(event: Event): Promise<void> {
-        await resetHandle();
-        const target = event.target;
+    async function clearImage(): Promise<void> {
+        if (activeImage && mathjaxElement) {
+            unsubscribe();
+            activeImage = null;
+            mathjaxElement = null;
+        }
 
+        await tick();
+        container.focus();
+    }
+
+    function placeCaret(image: HTMLImageElement): void {
+        placeCaretAfter(image);
+        image.removeAttribute(caretKeyword);
+    }
+
+    async function resetHandle(deletes: boolean = false): Promise<void> {
+        await clearImage();
+
+        const image = container.querySelector(`[${caretKeyword}]`);
+        if (image) {
+            placeCaret(image as HTMLImageElement);
+
+            if (deletes) {
+                image.remove();
+            }
+        }
+
+        allow();
+    }
+
+    async function maybeShowHandle({ target }: Event): Promise<void> {
+        await resetHandle();
         if (target instanceof HTMLImageElement && target.dataset.anki === "mathjax") {
             showHandle(target);
         }
@@ -45,71 +81,45 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
         showHandle(detail);
     }
 
-    async function resetHandle(): Promise<void> {
-        if (activeImage) {
-            allow();
-            activeImage = null;
-            await tick();
-        }
-    }
-
     onMount(() => {
-        container.addEventListener("click", maybeShowHandle);
-        container.addEventListener("focusmathjax" as any, showAutofocusHandle);
-        container.addEventListener("key", resetHandle);
-        container.addEventListener("paste", resetHandle);
+        const removeClick = on(container, "click", maybeShowHandle);
+        const removeFocus = on(container, "focusmathjax" as any, showAutofocusHandle);
 
         return () => {
-            container.removeEventListener("click", maybeShowHandle);
-            container.removeEventListener("focusmathjax" as any, showAutofocusHandle);
-            container.removeEventListener("key", resetHandle);
-            container.removeEventListener("paste", resetHandle);
+            removeClick();
+            removeFocus();
         };
     });
 
+    let updateSelection: () => Promise<void>;
+    let errorMessage: string;
     let dropdownApi: any;
+
     async function onImageResize(): Promise<void> {
-        if (activeImage) {
-            errorMessage = activeImage.title;
-            await updateSelection();
-            dropdownApi.update();
-        }
+        errorMessage = activeImage!.title;
+        await updateSelection();
+        dropdownApi.update();
     }
 
+    const resizeObserver = new ResizeObserver(onImageResize);
+
     let clearResize = noop;
     function handleImageResizing(activeImage: HTMLImageElement | null) {
         if (activeImage) {
-            activeImage.addEventListener("resize", onImageResize);
-
-            const lastImage = activeImage;
-            clearResize = () => lastImage.removeEventListener("resize", onImageResize);
+            resizeObserver.observe(container);
+            clearResize = on(activeImage, "resize", onImageResize);
         } else {
+            resizeObserver.unobserve(container);
             clearResize();
         }
     }
 
     $: handleImageResizing(activeImage);
 
-    const resizeObserver = new ResizeObserver(async () => {
-        if (activeImage) {
-            await updateSelection();
-            dropdownApi.update();
-        }
+    onDestroy(() => {
+        resizeObserver.disconnect();
+        clearResize();
     });
-
-    resizeObserver.observe(container);
-
-    let updateSelection: () => Promise<void>;
-    let errorMessage: string;
-
-    function getComponent(image: HTMLImageElement): HTMLElement {
-        return image.closest("anki-mathjax")! as HTMLElement;
-    }
-
-    function onEditorUpdate(event: CustomEvent): void {
-        /* this updates the image in Mathjax.svelte */
-        getComponent(activeImage!).dataset.mathjax = event.detail.mathjax;
-    }
 </script>
 
 <WithDropdown
@@ -119,37 +129,17 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     distance={4}
     let:createDropdown
 >
-    {#if activeImage}
-        <HandleSelection
-            image={activeImage}
+    {#if activeImage && mathjaxElement}
+        <MathjaxMenu
+            {activeImage}
+            {mathjaxElement}
             {container}
+            {errorMessage}
+            {code}
             bind:updateSelection
             on:mount={(event) => (dropdownApi = createDropdown(event.detail.selection))}
-        >
-            <HandleBackground tooltip={errorMessage} />
-
-            <HandleControl offsetX={1} offsetY={1} />
-        </HandleSelection>
-
-        <DropdownMenu>
-            <Editor
-                initialValue={getComponent(activeImage).dataset.mathjax ?? ""}
-                on:update={onEditorUpdate}
-                on:codemirrorblur={resetHandle}
-            />
-            <div class="margin-x">
-                <ButtonToolbar>
-                    <Item>
-                        <InlineBlock {activeImage} on:click={updateSelection} />
-                    </Item>
-                </ButtonToolbar>
-            </div>
-        </DropdownMenu>
+            on:reset={() => resetHandle(false)}
+            on:delete={() => resetHandle(true)}
+        />
     {/if}
 </WithDropdown>
-
-<style lang="scss">
-    .margin-x {
-        margin: 0 0.125rem;
-    }
-</style>

ts/editor/mathjax-overlay/MathjaxMenu.svelte

@@ -0,0 +1,69 @@
+<!--
+Copyright: Ankitects Pty Ltd and contributors
+License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+-->
+<script lang="ts">
+    import Shortcut from "../../components/Shortcut.svelte";
+    import DropdownMenu from "../../components/DropdownMenu.svelte";
+    import HandleSelection from "../HandleSelection.svelte";
+    import HandleBackground from "../HandleBackground.svelte";
+    import HandleControl from "../HandleControl.svelte";
+    import MathjaxEditor from "./MathjaxEditor.svelte";
+    import MathjaxButtons from "./MathjaxButtons.svelte";
+    import type { Writable } from "svelte/store";
+    import { createEventDispatcher } from "svelte";
+
+    export let activeImage: HTMLImageElement;
+    export let mathjaxElement: HTMLElement;
+    export let container: HTMLElement;
+    export let errorMessage: string;
+    export let code: Writable<string>;
+
+    const acceptShortcut = "Enter";
+    const newlineShortcut = "Shift+Enter";
+
+    function appendNewline(): void {
+        code.update((value) => `${value}\n`);
+    }
+
+    export let updateSelection: () => Promise<void>;
+    let dropdownApi: any;
+
+    export async function update() {
+        await updateSelection?.();
+        dropdownApi.update();
+    }
+
+    const dispatch = createEventDispatcher();
+</script>
+
+<div class="mathjax-menu">
+    <HandleSelection image={activeImage} {container} bind:updateSelection on:mount>
+        <HandleBackground tooltip={errorMessage} />
+        <HandleControl offsetX={1} offsetY={1} />
+    </HandleSelection>
+
+    <DropdownMenu>
+        <MathjaxEditor
+            {acceptShortcut}
+            {newlineShortcut}
+            {code}
+            on:blur={() => dispatch("reset")}
+        />
+
+        <Shortcut keyCombination={acceptShortcut} on:action={() => dispatch("reset")} />
+        <Shortcut keyCombination={newlineShortcut} on:action={appendNewline} />
+
+        <MathjaxButtons
+            {activeImage}
+            {mathjaxElement}
+            on:delete={() => dispatch("delete")}
+        />
+    </DropdownMenu>
+</div>
+
+<style lang="scss">
+    .mathjax-menu :global(.dropdown-menu) {
+        border-color: var(--border);
+    }
+</style>

ts/editor/mathjax-overlay/icons.ts

@@ -3,3 +3,4 @@
 
 export { default as inlineIcon } from "@mdi/svg/svg/format-wrap-square.svg";
 export { default as blockIcon } from "@mdi/svg/svg/format-wrap-top-bottom.svg";
+export { default as deleteIcon } from "@mdi/svg/svg/delete.svg";

ts/lib/events.ts

@@ -31,3 +31,7 @@ export function on<T extends EventTarget, K extends keyof EventTargetToMap<T>>(
     return () =>
         target.removeEventListener(eventType, handler as EventListener, options);
 }
+
+export function preventDefault(event: Event): void {
+    event.preventDefault();
+}

ts/lib/uuid.ts

@@ -0,0 +1,17 @@
+// Copyright: Ankitects Pty Ltd and contributors
+// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
+
+/**
+ * TODO replace with crypto.randomUUID
+ */
+export function randomUUID(): string {
+    const value = `${1e7}-${1e3}-${4e3}-${8e3}-${1e11}`;
+
+    return value.replace(/[018]/g, (character: string): string =>
+        (
+            Number(character) ^
+            (crypto.getRandomValues(new Uint8Array(1))[0] &
+                (15 >> (Number(character) / 4)))
+        ).toString(16),
+    );
+}