feat(acp): add experimental ACP support

Co-authored-by: Jonathan Taylor <visionik@pobox.com>

src/acp/session.ts

@@ -0,0 +1,93 @@
+import { randomUUID } from "node:crypto";
+
+import type { AcpSession } from "./types.js";
+
+export type AcpSessionStore = {
+  createSession: (params: {
+    sessionKey: string;
+    cwd: string;
+    sessionId?: string;
+  }) => AcpSession;
+  getSession: (sessionId: string) => AcpSession | undefined;
+  getSessionByRunId: (runId: string) => AcpSession | undefined;
+  setActiveRun: (sessionId: string, runId: string, abortController: AbortController) => void;
+  clearActiveRun: (sessionId: string) => void;
+  cancelActiveRun: (sessionId: string) => boolean;
+  clearAllSessionsForTest: () => void;
+};
+
+export function createInMemorySessionStore(): AcpSessionStore {
+  const sessions = new Map<string, AcpSession>();
+  const runIdToSessionId = new Map<string, string>();
+
+  const createSession: AcpSessionStore["createSession"] = (params) => {
+    const sessionId = params.sessionId ?? randomUUID();
+    const session: AcpSession = {
+      sessionId,
+      sessionKey: params.sessionKey,
+      cwd: params.cwd,
+      createdAt: Date.now(),
+      abortController: null,
+      activeRunId: null,
+    };
+    sessions.set(sessionId, session);
+    return session;
+  };
+
+  const getSession: AcpSessionStore["getSession"] = (sessionId) => sessions.get(sessionId);
+
+  const getSessionByRunId: AcpSessionStore["getSessionByRunId"] = (runId) => {
+    const sessionId = runIdToSessionId.get(runId);
+    return sessionId ? sessions.get(sessionId) : undefined;
+  };
+
+  const setActiveRun: AcpSessionStore["setActiveRun"] = (
+    sessionId,
+    runId,
+    abortController,
+  ) => {
+    const session = sessions.get(sessionId);
+    if (!session) return;
+    session.activeRunId = runId;
+    session.abortController = abortController;
+    runIdToSessionId.set(runId, sessionId);
+  };
+
+  const clearActiveRun: AcpSessionStore["clearActiveRun"] = (sessionId) => {
+    const session = sessions.get(sessionId);
+    if (!session) return;
+    if (session.activeRunId) runIdToSessionId.delete(session.activeRunId);
+    session.activeRunId = null;
+    session.abortController = null;
+  };
+
+  const cancelActiveRun: AcpSessionStore["cancelActiveRun"] = (sessionId) => {
+    const session = sessions.get(sessionId);
+    if (!session?.abortController) return false;
+    session.abortController.abort();
+    if (session.activeRunId) runIdToSessionId.delete(session.activeRunId);
+    session.abortController = null;
+    session.activeRunId = null;
+    return true;
+  };
+
+  const clearAllSessionsForTest: AcpSessionStore["clearAllSessionsForTest"] = () => {
+    for (const session of sessions.values()) {
+      session.abortController?.abort();
+    }
+    sessions.clear();
+    runIdToSessionId.clear();
+  };
+
+  return {
+    createSession,
+    getSession,
+    getSessionByRunId,
+    setActiveRun,
+    clearActiveRun,
+    cancelActiveRun,
+    clearAllSessionsForTest,
+  };
+}
+
+export const defaultAcpSessionStore = createInMemorySessionStore();