CodeQL model editor: Add support for free text input in type models (#3217)

extensions/ql-vscode/src/view/common/useDebounceCallback.ts

@@ -0,0 +1,27 @@
+import { useEffect, useRef } from "react";
+
+/**
+ * Call the callback after the value has not changed for a certain amount of time.
+ * @param value
+ * @param callback
+ * @param delay
+ */
+export function useDebounceCallback<T>(
+  value: T,
+  callback: (value: T) => void,
+  delay?: number,
+) {
+  const callbackRef = useRef<(value: T) => void>(callback);
+
+  useEffect(() => {
+    callbackRef.current = callback;
+  }, [callback]);
+
+  useEffect(() => {
+    const timer = setTimeout(() => callbackRef.current(value), delay || 500);
+
+    return () => {
+      clearTimeout(timer);
+    };
+  }, [value, delay]);
+}

extensions/ql-vscode/src/view/model-editor/ModelInputDropdown.tsx

@@ -7,11 +7,11 @@ import {
   modeledMethodSupportsInput,
 } from "../../model-editor/modeled-method";
 import type { Method } from "../../model-editor/method";
-import { ReadonlyDropdown } from "../common/ReadonlyDropdown";
 import type { QueryLanguage } from "../../common/query-language";
 import { getModelsAsDataLanguage } from "../../model-editor/languages";
 import type { ModelingStatus } from "../../model-editor/shared/modeling-status";
 import { InputDropdown } from "./InputDropdown";
+import { ModelTypeTextbox } from "./ModelTypeTextbox";
 
 type Props = {
   language: QueryLanguage;
@@ -67,7 +67,14 @@ export const ModelInputDropdown = ({
       : undefined;
 
   if (modeledMethod?.type === "type") {
-    return <ReadonlyDropdown value={modeledMethod.path} aria-label="Path" />;
+    return (
+      <ModelTypeTextbox
+        modeledMethod={modeledMethod}
+        typeInfo="path"
+        onChange={onChange}
+        aria-label="Path"
+      />
+    );
   }
 
   const modelAccepted = isModelAccepted(modeledMethod, modelingStatus);

extensions/ql-vscode/src/view/model-editor/ModelOutputDropdown.tsx

@@ -7,11 +7,11 @@ import {
   modeledMethodSupportsOutput,
 } from "../../model-editor/modeled-method";
 import type { Method } from "../../model-editor/method";
-import { ReadonlyDropdown } from "../common/ReadonlyDropdown";
 import { getModelsAsDataLanguage } from "../../model-editor/languages";
 import type { QueryLanguage } from "../../common/query-language";
 import type { ModelingStatus } from "../../model-editor/shared/modeling-status";
 import { InputDropdown } from "./InputDropdown";
+import { ModelTypeTextbox } from "./ModelTypeTextbox";
 
 type Props = {
   language: QueryLanguage;
@@ -69,8 +69,10 @@ export const ModelOutputDropdown = ({
 
   if (modeledMethod?.type === "type") {
     return (
-      <ReadonlyDropdown
-        value={modeledMethod.relatedTypeName}
+      <ModelTypeTextbox
+        modeledMethod={modeledMethod}
+        typeInfo="relatedTypeName"
+        onChange={onChange}
         aria-label="Related type name"
       />
     );

extensions/ql-vscode/src/view/model-editor/ModelTypeTextbox.tsx

@@ -0,0 +1,52 @@
+import type { ChangeEvent } from "react";
+import { useCallback, useEffect, useState } from "react";
+import type {
+  ModeledMethod,
+  TypeModeledMethod,
+} from "../../model-editor/modeled-method";
+import { VSCodeTextField } from "@vscode/webview-ui-toolkit/react";
+import { useDebounceCallback } from "../common/useDebounceCallback";
+
+type Props = {
+  modeledMethod: TypeModeledMethod;
+  typeInfo: "path" | "relatedTypeName";
+  onChange: (modeledMethod: ModeledMethod) => void;
+
+  "aria-label"?: string;
+};
+
+export const ModelTypeTextbox = ({
+  modeledMethod,
+  typeInfo,
+  onChange,
+  ...props
+}: Props): JSX.Element => {
+  const [value, setValue] = useState<string | undefined>(
+    modeledMethod[typeInfo],
+  );
+
+  useEffect(() => {
+    setValue(modeledMethod[typeInfo]);
+  }, [modeledMethod, typeInfo]);
+
+  const handleChange = useCallback((e: ChangeEvent<HTMLSelectElement>) => {
+    const target = e.target as HTMLSelectElement;
+
+    setValue(target.value);
+  }, []);
+
+  // Debounce the callback to avoid updating the model too often.
+  // Not doing this results in a lot of lag when typing.
+  useDebounceCallback(
+    value,
+    (newValue: string | undefined) => {
+      onChange({
+        ...modeledMethod,
+        [typeInfo]: newValue ?? "",
+      });
+    },
+    500,
+  );
+
+  return <VSCodeTextField value={value} onInput={handleChange} {...props} />;
+};