Fixes #158

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;
+  }
+}