feat(acp): add interactive client harness

src/acp/client.ts

@@ -0,0 +1,185 @@
+import { spawn, type ChildProcess } from "node:child_process";
+import * as readline from "node:readline";
+import { Readable, Writable } from "node:stream";
+
+import {
+  ClientSideConnection,
+  PROTOCOL_VERSION,
+  ndJsonStream,
+  type SessionNotification,
+} from "@agentclientprotocol/sdk";
+
+import { ensureClawdbotCliOnPath } from "../infra/path-env.js";
+
+export type AcpClientOptions = {
+  cwd?: string;
+  serverCommand?: string;
+  serverArgs?: string[];
+  serverVerbose?: boolean;
+  verbose?: boolean;
+};
+
+export type AcpClientHandle = {
+  client: ClientSideConnection;
+  agent: ChildProcess;
+  sessionId: string;
+};
+
+function toArgs(value: string[] | string | undefined): string[] {
+  if (!value) return [];
+  return Array.isArray(value) ? value : [value];
+}
+
+function buildServerArgs(opts: AcpClientOptions): string[] {
+  const args = ["acp", ...toArgs(opts.serverArgs)];
+  if (opts.serverVerbose && !args.includes("--verbose") && !args.includes("-v")) {
+    args.push("--verbose");
+  }
+  return args;
+}
+
+function printSessionUpdate(notification: SessionNotification): void {
+  const update = notification.update;
+  if (!("sessionUpdate" in update)) return;
+
+  switch (update.sessionUpdate) {
+    case "agent_message_chunk": {
+      if (update.content?.type === "text") {
+        process.stdout.write(update.content.text);
+      }
+      return;
+    }
+    case "tool_call": {
+      console.log(`\n[tool] ${update.title} (${update.status})`);
+      return;
+    }
+    case "tool_call_update": {
+      if (update.status) {
+        console.log(`[tool update] ${update.toolCallId}: ${update.status}`);
+      }
+      return;
+    }
+    case "available_commands_update": {
+      const names = update.availableCommands?.map((cmd) => `/${cmd.name}`).join(" ");
+      if (names) console.log(`\n[commands] ${names}`);
+      return;
+    }
+    default:
+      return;
+  }
+}
+
+export async function createAcpClient(opts: AcpClientOptions = {}): Promise<AcpClientHandle> {
+  const cwd = opts.cwd ?? process.cwd();
+  const verbose = Boolean(opts.verbose);
+  const log = verbose ? (msg: string) => console.error(`[acp-client] ${msg}`) : () => {};
+
+  ensureClawdbotCliOnPath({ cwd });
+  const serverCommand = opts.serverCommand ?? "clawdbot";
+  const serverArgs = buildServerArgs(opts);
+
+  log(`spawning: ${serverCommand} ${serverArgs.join(" ")}`);
+
+  const agent = spawn(serverCommand, serverArgs, {
+    stdio: ["pipe", "pipe", "inherit"],
+    cwd,
+  });
+
+  if (!agent.stdin || !agent.stdout) {
+    throw new Error("Failed to create ACP stdio pipes");
+  }
+
+  const input = Writable.toWeb(agent.stdin);
+  const output = Readable.toWeb(agent.stdout) as ReadableStream<Uint8Array>;
+  const stream = ndJsonStream(input, output);
+
+  const client = new ClientSideConnection(
+    () => ({
+      sessionUpdate: async (params: SessionNotification) => {
+        printSessionUpdate(params);
+      },
+      requestPermission: async (params) => {
+        console.log("\n[permission requested]", params.toolCall?.title ?? "tool");
+        const allowOnce = params.options.find((option) => option.kind === "allow_once");
+        const fallback = params.options[0];
+        return {
+          outcome: {
+            outcome: "selected",
+            optionId: allowOnce?.optionId ?? fallback?.optionId ?? "allow",
+          },
+        };
+      },
+    }),
+    stream,
+  );
+
+  log("initializing");
+  await client.initialize({
+    protocolVersion: PROTOCOL_VERSION,
+    clientCapabilities: {
+      fs: { readTextFile: true, writeTextFile: true },
+      terminal: true,
+    },
+    clientInfo: { name: "clawdbot-acp-client", version: "1.0.0" },
+  });
+
+  log("creating session");
+  const session = await client.newSession({
+    cwd,
+    mcpServers: [],
+  });
+
+  return {
+    client,
+    agent,
+    sessionId: session.sessionId,
+  };
+}
+
+export async function runAcpClientInteractive(opts: AcpClientOptions = {}): Promise<void> {
+  const { client, agent, sessionId } = await createAcpClient(opts);
+
+  const rl = readline.createInterface({
+    input: process.stdin,
+    output: process.stdout,
+  });
+
+  console.log("Clawdbot ACP client");
+  console.log(`Session: ${sessionId}`);
+  console.log('Type a prompt, or "exit" to quit.\n');
+
+  const prompt = () => {
+    rl.question("> ", async (input) => {
+      const text = input.trim();
+      if (!text) {
+        prompt();
+        return;
+      }
+      if (text === "exit" || text === "quit") {
+        agent.kill();
+        rl.close();
+        process.exit(0);
+      }
+
+      try {
+        const response = await client.prompt({
+          sessionId,
+          prompt: [{ type: "text", text }],
+        });
+        console.log(`\n[${response.stopReason}]\n`);
+      } catch (err) {
+        console.error(`\n[error] ${String(err)}\n`);
+      }
+
+      prompt();
+    });
+  };
+
+  prompt();
+
+  agent.on("exit", (code) => {
+    console.log(`\nAgent exited with code ${code ?? 0}`);
+    rl.close();
+    process.exit(code ?? 0);
+  });
+}