[Init] Initial commit - NetMesh terminal manager

components/terminal/runtime/cursorPreference.ts

@@ -0,0 +1,118 @@
+import type { IDisposable, Terminal as XTerm } from "@xterm/xterm";
+import type { RefObject } from "react";
+
+import type { TerminalSettings } from "../../../types";
+
+type CursorPreferenceSettings = Pick<TerminalSettings, "cursorShape" | "cursorBlink">;
+
+type MutableCursorOptions = {
+  cursorStyle?: "block" | "bar" | "underline";
+  cursorBlink?: boolean;
+};
+
+type TerminalLike = {
+  options: MutableCursorOptions;
+  parser?: {
+    registerCsiHandler?: (
+      id: { prefix?: string; intermediates?: string; final: string },
+      callback: (params: readonly (number | number[])[]) => boolean,
+    ) => IDisposable;
+  };
+  _core?: {
+    coreService?: {
+      decPrivateModes?: {
+        cursorStyle?: "block" | "bar" | "underline";
+        cursorBlink?: boolean;
+      };
+    };
+  };
+};
+
+const scheduleAfterDefaultHandler = (callback: () => void): void => {
+  if (typeof queueMicrotask === "function") {
+    queueMicrotask(callback);
+    return;
+  }
+
+  setTimeout(callback, 0);
+};
+
+const hasCursorBlinkPrivateModeParam = (params: readonly (number | number[])[]): boolean => (
+  params.some((param) => (
+    Array.isArray(param)
+      ? param.includes(12)
+      : param === 12
+  ))
+);
+
+export const resolveUserCursorPreference = (
+  settings: Partial<CursorPreferenceSettings> | undefined,
+): Required<CursorPreferenceSettings> => ({
+  cursorShape: settings?.cursorShape ?? "block",
+  cursorBlink: settings?.cursorBlink ?? true,
+});
+
+export const applyUserCursorPreference = (
+  term: TerminalLike,
+  settings: Partial<CursorPreferenceSettings> | undefined,
+): void => {
+  const preference = resolveUserCursorPreference(settings);
+  const privateModes = term._core?.coreService?.decPrivateModes;
+  if (privateModes) {
+    privateModes.cursorStyle = undefined;
+    privateModes.cursorBlink = undefined;
+  }
+  term.options.cursorStyle = preference.cursorShape;
+  term.options.cursorBlink = preference.cursorBlink;
+};
+
+export const applyUserCursorBlinkPreference = (
+  term: TerminalLike,
+  settings: Partial<CursorPreferenceSettings> | undefined,
+): void => {
+  const preference = resolveUserCursorPreference(settings);
+  const privateModes = term._core?.coreService?.decPrivateModes;
+  if (privateModes) {
+    privateModes.cursorBlink = undefined;
+  }
+  term.options.cursorBlink = preference.cursorBlink;
+};
+
+export const installUserCursorPreferenceGuard = (
+  term: XTerm | TerminalLike,
+  terminalSettingsRef: RefObject<TerminalSettings | undefined>,
+): IDisposable | null => {
+  const terminal = term as TerminalLike;
+  const parser = terminal.parser;
+  if (!parser?.registerCsiHandler) return null;
+  const registerCsiHandler = parser.registerCsiHandler.bind(parser);
+
+  const applyBlinkPreference = () => applyUserCursorBlinkPreference(terminal, terminalSettingsRef.current);
+
+  const cursorStyleDisposable = registerCsiHandler({ intermediates: " ", final: "q" }, () => {
+    scheduleAfterDefaultHandler(applyBlinkPreference);
+    return false;
+  });
+
+  const cursorBlinkSetDisposable = registerCsiHandler({ prefix: "?", final: "h" }, (params) => {
+    if (hasCursorBlinkPrivateModeParam(params)) {
+      scheduleAfterDefaultHandler(applyBlinkPreference);
+    }
+    return false;
+  });
+
+  const cursorBlinkResetDisposable = registerCsiHandler({ prefix: "?", final: "l" }, (params) => {
+    if (hasCursorBlinkPrivateModeParam(params)) {
+      scheduleAfterDefaultHandler(applyBlinkPreference);
+    }
+    return false;
+  });
+
+  return {
+    dispose: () => {
+      cursorStyleDisposable.dispose();
+      cursorBlinkSetDisposable.dispose();
+      cursorBlinkResetDisposable.dispose();
+    },
+  };
+};