Fixes #158

common/manifest.ts

@@ -5,6 +5,7 @@ import { EventHookT } from "../plugos/hooks/event.ts";
 import { CommandHookT } from "../web/hooks/command.ts";
 import { SlashCommandHookT } from "../web/hooks/slash_command.ts";
 import { PageNamespaceHookT } from "../server/hooks/page_namespace.ts";
+import { CodeWidgetT } from "../web/hooks/code_widget.ts";
 
 export type SilverBulletHooks =
   & CommandHookT
@@ -12,6 +13,7 @@ export type SilverBulletHooks =
   & EndpointHookT
   & CronHookT
   & EventHookT
+  & CodeWidgetT
   & PageNamespaceHookT;
 
 export type SyntaxExtensions = {

plugs/markdown/markdown.plug.yaml

@@ -30,4 +30,8 @@ functions:
   sharePublisher:
     path: ./share.ts:sharePublisher
     events:
-    - share:file
+    - share:file
+
+  markdownWidget:
+    path: ./widget.ts:markdownWidget
+    codeWidget: markdown

plugs/markdown/widget.ts

@@ -0,0 +1,19 @@
+import { parseMarkdown } from "$sb/silverbullet-syscall/markdown.ts";
+import { renderMarkdownToHtml } from "./markdown_render.ts";
+
+export async function markdownWidget(
+  bodyText: string,
+): Promise<{ html: string; script: string }> {
+  const mdTree = await parseMarkdown(bodyText);
+
+  const html = renderMarkdownToHtml(mdTree, {
+    smartHardBreak: true,
+  });
+  return Promise.resolve({
+    html: html,
+    script: `updateHeight();
+    document.addEventListener("click", () => {
+      api({type: "blur"});
+    });`,
+  });
+}

web/cm_plugins/block.ts

@@ -52,23 +52,6 @@ function hideNodes(state: EditorState) {
           }
         }
       }
-
-      if (
-        node.name === "CodeMark"
-      ) {
-        const parent = node.node.parent!;
-        // Hide ONLY if CodeMark is not insine backticks (InlineCode) and the cursor is placed outside
-        if (
-          parent.node.name !== "InlineCode" &&
-          !isCursorInRange(state, [parent.from, parent.to])
-        ) {
-          widgets.push(
-            Decoration.line({
-              class: "sb-line-code-outside",
-            }).range(node.from),
-          );
-        }
-      }
     },
   });
   return Decoration.set(widgets, true);

web/cm_plugins/clean.ts

@@ -12,6 +12,7 @@ import { tablePlugin } from "./table.ts";
 import { taskListPlugin } from "./task.ts";
 import { cleanWikiLinkPlugin } from "./wiki_link.ts";
 import { cleanCommandLinkPlugin } from "./command_link.ts";
+import { fencedCodePlugin } from "./fenced_code.ts";
 
 export function cleanModePlugins(editor: Editor) {
   return [
@@ -22,6 +23,7 @@ export function cleanModePlugins(editor: Editor) {
     hideMarksPlugin(),
     hideHeaderMarkPlugin(),
     cleanBlockPlugin(),
+    fencedCodePlugin(editor),
     taskListPlugin({
       // TODO: Move this logic elsewhere?
       onCheckboxClick: (pos) => {

web/cm_plugins/fenced_code.ts

@@ -0,0 +1,176 @@
+import { panelHtml } from "../components/panel.tsx";
+import { Decoration, EditorState, syntaxTree, WidgetType } from "../deps.ts";
+import type { Editor } from "../editor.tsx";
+import { CodeWidgetCallback } from "../hooks/code_widget.ts";
+import {
+  decoratorStateField,
+  invisibleDecoration,
+  isCursorInRange,
+} from "./util.ts";
+
+class IFrameWidget extends WidgetType {
+  constructor(
+    readonly from: number,
+    readonly to: number,
+    readonly editor: Editor,
+    readonly bodyText: string,
+    readonly codeWidgetCallback: CodeWidgetCallback,
+  ) {
+    super();
+  }
+
+  toDOM(): HTMLElement {
+    const iframe = document.createElement("iframe");
+    iframe.srcdoc = panelHtml;
+    // iframe.style.height = "0";
+
+    const messageListener = (evt: any) => {
+      if (evt.source !== iframe.contentWindow) {
+        return;
+      }
+      const data = evt.data;
+      if (!data) {
+        return;
+      }
+      switch (data.type) {
+        case "event":
+          this.editor.dispatchAppEvent(data.name, ...data.args);
+          break;
+        case "setHeight":
+          iframe.style.height = data.height + "px";
+          break;
+        case "setBody":
+          this.editor.editorView!.dispatch({
+            changes: {
+              from: this.from,
+              to: this.to,
+              insert: data.body,
+            },
+          });
+          break;
+        case "blur":
+          this.editor.editorView!.dispatch({
+            selection: { anchor: this.from },
+          });
+          this.editor.focus();
+          break;
+      }
+    };
+
+    iframe.onload = () => {
+      // Subscribe to message event on global object (to receive messages from iframe)
+      globalThis.addEventListener("message", messageListener);
+      this.codeWidgetCallback(this.bodyText).then(({ html, script }) => {
+        iframe.contentWindow!.postMessage({
+          type: "html",
+          html,
+          script,
+        });
+        iframe.contentWindow!.onunload = () => {
+          // Unsubscribing from events
+          globalThis.removeEventListener("message", messageListener);
+        };
+      });
+    };
+    return iframe;
+  }
+
+  eq(other: WidgetType): boolean {
+    return (
+      other instanceof IFrameWidget &&
+      other.bodyText === this.bodyText
+    );
+  }
+}
+
+export function fencedCodePlugin(editor: Editor) {
+  return decoratorStateField((state: EditorState) => {
+    const widgets: any[] = [];
+    syntaxTree(state).iterate({
+      enter({ from, to, name, node }) {
+        if (name === "FencedCode") {
+          if (isCursorInRange(state, [from, to])) return;
+          const text = state.sliceDoc(from, to);
+          const [_, lang] = text.match(/^```(\w+)?/)!;
+          const codeWidgetCallback = editor.codeWidgetHook.codeWidgetCallbacks
+            .get(lang);
+          if (codeWidgetCallback) {
+            // We got a custom renderer!
+            const lineStrings = text.split("\n");
+
+            const lines: { from: number; to: number }[] = [];
+            let fromIt = from;
+            for (const line of lineStrings) {
+              lines.push({
+                from: fromIt,
+                to: fromIt + line.length,
+              });
+              fromIt += line.length + 1;
+            }
+
+            const firstLine = lines[0], lastLine = lines[lines.length - 1];
+
+            // In case of doubt, back out
+            if (!firstLine || !lastLine) return;
+
+            widgets.push(
+              invisibleDecoration.range(firstLine.from, firstLine.to),
+            );
+            widgets.push(
+              invisibleDecoration.range(lastLine.from, lastLine.to),
+            );
+            widgets.push(
+              Decoration.line({
+                class: "sb-fenced-code-iframe",
+              }).range(firstLine.from),
+            );
+            widgets.push(
+              Decoration.line({
+                class: "sb-fenced-code-hide",
+              }).range(lastLine.from),
+            );
+
+            lines.slice(1, lines.length - 1).forEach((line) => {
+              widgets.push(
+                Decoration.line({ class: "sb-line-table-outside" }).range(
+                  line.from,
+                ),
+              );
+            });
+
+            widgets.push(
+              Decoration.widget({
+                widget: new IFrameWidget(
+                  from + lineStrings[0].length + 1,
+                  to - lineStrings[lineStrings.length - 1].length - 1,
+                  editor,
+                  lineStrings.slice(1, lineStrings.length - 1).join("\n"),
+                  codeWidgetCallback,
+                ),
+              }).range(from),
+            );
+            return false;
+          }
+          return true;
+        }
+        if (
+          name === "CodeMark"
+        ) {
+          const parent = node.parent!;
+          // Hide ONLY if CodeMark is not insine backticks (InlineCode) and the cursor is placed outside
+          if (
+            parent.node.name !== "InlineCode" &&
+            !isCursorInRange(state, [parent.from, parent.to])
+          ) {
+            widgets.push(
+              Decoration.line({
+                class: "sb-line-code-outside",
+              }).range(node.from),
+            );
+          }
+        }
+      },
+    });
+    return Decoration.set(widgets, true);
+  });
+}

web/components/panel.tsx

@@ -2,7 +2,7 @@ import { useEffect, useRef } from "../deps.ts";
 import { Editor } from "../editor.tsx";
 import { PanelConfig } from "../types.ts";
 
-const panelHtml = `<!DOCTYPE html>
+export const panelHtml = `<!DOCTYPE html>
 <html lang="en">
 <head>
     <meta charset="UTF-8">
@@ -25,14 +25,27 @@ window.addEventListener("message", (message) => {
 });
 
 function sendEvent(name, ...args) {
-  window.parent.postMessage(
-    {
-      type: "event",
-      name,
-      args,
-    },
-    "*"
-  );
+  window.parent.postMessage({ type: "event", name, args, }, "*");
+}
+function api(obj) {
+  window.parent.postMessage(obj, "*");
+}
+function updateHeight() {
+  api({
+    type: "setHeight", 
+    height: document.documentElement.offsetHeight,
+  });
+}
+
+function loadJsByUrl(url) {
+  const script = document.createElement("script");
+  script.src = url;
+
+  return new Promise((resolve) => {
+    script.onload = resolve;
+  
+    document.documentElement.firstChild.appendChild(script);
+  });
 }
 </script>
 </head>

web/editor.tsx

@@ -89,19 +89,13 @@ import { storeSyscalls } from "./syscalls/store.ts";
 import { systemSyscalls } from "./syscalls/system.ts";
 import { AppViewState, BuiltinSettings, initialViewState } from "./types.ts";
 
-// Third-party dependencies
-// PlugOS Dependencies
-// Syscalls
-// State and state transitions
 import type {
   AppEvent,
   ClickEvent,
   CompleteEvent,
 } from "../plug-api/app_event.ts";
+import { CodeWidgetHook } from "./hooks/code_widget.ts";
 
-// UI Components
-// CodeMirror plugins
-// Real-time collaboration
 const frontMatterRegex = /^---\n(.*?)---\n/ms;
 
 class PageState {
@@ -124,6 +118,8 @@ export class Editor {
   space: Space;
   pageNavigator: PathPageNavigator;
   eventHook: EventHook;
+  codeWidgetHook: CodeWidgetHook;
+
   saveTimeout: any;
   debouncedUpdateEvent = throttle(() => {
     this.eventHook
@@ -157,6 +153,10 @@ export class Editor {
     this.eventHook = new EventHook();
     this.system.addHook(this.eventHook);
 
+    // Code widget hook
+    this.codeWidgetHook = new CodeWidgetHook();
+    this.system.addHook(this.codeWidgetHook);
+
     // Command hook
     this.commandHook = new CommandHook();
     this.commandHook.on({

web/hooks/code_widget.ts

@@ -0,0 +1,57 @@
+import { Hook, Manifest } from "../../plugos/types.ts";
+import { System } from "../../plugos/system.ts";
+
+export type CodeWidgetT = {
+  codeWidget?: string;
+};
+
+export type CodeWidgetCallback = (
+  bodyText: string,
+) => Promise<{ html: string; script: string }>;
+
+export class CodeWidgetHook implements Hook<CodeWidgetT> {
+  codeWidgetCallbacks = new Map<string, CodeWidgetCallback>();
+
+  constructor() {
+  }
+
+  collectAllCodeWidgets(system: System<CodeWidgetT>) {
+    this.codeWidgetCallbacks.clear();
+    for (const plug of system.loadedPlugs.values()) {
+      for (
+        const [name, functionDef] of Object.entries(
+          plug.manifest!.functions,
+        )
+      ) {
+        if (!functionDef.codeWidget) {
+          continue;
+        }
+        this.codeWidgetCallbacks.set(functionDef.codeWidget, (bodyText) => {
+          return plug.invoke(name, [bodyText]);
+        });
+      }
+    }
+  }
+
+  apply(system: System<CodeWidgetT>): void {
+    this.collectAllCodeWidgets(system);
+    system.on({
+      plugLoaded: () => {
+        this.collectAllCodeWidgets(system);
+      },
+    });
+  }
+
+  validateManifest(manifest: Manifest<CodeWidgetT>): string[] {
+    const errors = [];
+    for (const functionDef of Object.values(manifest.functions)) {
+      if (!functionDef.codeWidget) {
+        continue;
+      }
+      if (typeof functionDef.codeWidget !== "string") {
+        errors.push(`Codewidgets require a string name.`);
+      }
+    }
+    return errors;
+  }
+}

web/styles/editor.scss

@@ -211,6 +211,22 @@
     }
   }
 
+  .sb-fenced-code-hide {
+    background-color: transparent !important;
+    line-height: 0;
+  }
+
+  .sb-fenced-code-iframe {
+    background-color: transparent !important;
+
+    iframe {
+      border: 0;
+      width: 100%;
+      padding: 0;
+      margin: 0;
+    }
+  }
+
   .sb-line-blockquote {
     border-left: 1px solid rgb(74, 74, 74);
   }