import net from "node:net";
import { beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
import { stripAnsi } from "../terminal/ansi.js";

const runCommandWithTimeoutMock = vi.hoisted(() => vi.fn());

vi.mock("../process/exec.js", () => ({
  runCommandWithTimeout: (...args: unknown[]) => runCommandWithTimeoutMock(...args),
}));

let inspectPortUsage: typeof import("./ports-inspect.js").inspectPortUsage;
let ensurePortAvailable: typeof import("./ports.js").ensurePortAvailable;
let handlePortError: typeof import("./ports.js").handlePortError;
let PortInUseError: typeof import("./ports.js").PortInUseError;

const describeUnix = process.platform === "win32" ? describe.skip : describe;

async function listenServer(
  server: net.Server,
  port: number,
  host?: string,
): Promise<net.AddressInfo | null> {
  try {
    await new Promise<void>((resolve, reject) => {
      server.once("error", reject);
      if (host) {
        server.listen(port, host, resolve);
        return;
      }
      server.listen(port, resolve);
    });
  } catch (err) {
    const code = (err as NodeJS.ErrnoException).code;
    if (code === "EPERM" || code === "EACCES") {
      return null;
    }
    throw err;
  }

  const address = server.address();
  if (!address || typeof address === "string") {
    throw new Error("expected tcp address");
  }
  return address;
}

beforeAll(async () => {
  ({ inspectPortUsage } = await import("./ports-inspect.js"));
  ({ ensurePortAvailable, handlePortError, PortInUseError } = await import("./ports.js"));
});

beforeEach(() => {
  runCommandWithTimeoutMock.mockReset();
});

describe("ports helpers", () => {
  it("ensurePortAvailable rejects when port busy", async () => {
    const server = net.createServer();
    const address = await listenServer(server, 0);
    if (!address) {
      return;
    }
    const port = address.port;
    await expect(ensurePortAvailable(port)).rejects.toBeInstanceOf(PortInUseError);
    await new Promise<void>((resolve) => server.close(() => resolve()));
  });

  it("handlePortError exits nicely on EADDRINUSE", async () => {
    const runtime = {
      error: vi.fn(),
      log: vi.fn(),
      exit: vi.fn() as unknown as (code: number) => never,
    };
    // Avoid slow OS port inspection; this test only cares about messaging + exit behavior.
    await handlePortError(new PortInUseError(1234, "details"), 1234, "context", runtime).catch(
      () => {},
    );
    const messages = runtime.error.mock.calls.map((call) => stripAnsi(String(call[0] ?? "")));
    expect(messages.join("\n")).toContain("context failed: port 1234 is already in use.");
    expect(messages.join("\n")).toContain("Resolve by stopping the process");
    expect(runtime.exit).toHaveBeenCalledWith(1);
  });

  it("prints an OpenClaw-specific hint when port details look like another OpenClaw instance", async () => {
    const runtime = {
      error: vi.fn(),
      log: vi.fn(),
      exit: vi.fn() as unknown as (code: number) => never,
    };

    await handlePortError(
      new PortInUseError(18789, "node dist/index.js openclaw gateway"),
      18789,
      "gateway start",
      runtime,
    ).catch(() => {});

    const messages = runtime.error.mock.calls.map((call) => stripAnsi(String(call[0] ?? "")));
    expect(messages.join("\n")).toContain("another OpenClaw instance is already running");
  });
});

describeUnix("inspectPortUsage", () => {
  it("reports busy when lsof is missing but loopback listener exists", async () => {
    const server = net.createServer();
    const address = await listenServer(server, 0, "127.0.0.1");
    if (!address) {
      return;
    }
    const port = address.port;

    runCommandWithTimeoutMock.mockRejectedValueOnce(
      Object.assign(new Error("spawn lsof ENOENT"), { code: "ENOENT" }),
    );

    try {
      const result = await inspectPortUsage(port);
      expect(result.status).toBe("busy");
      expect(result.errors?.some((err) => err.includes("ENOENT"))).toBe(true);
    } finally {
      await new Promise<void>((resolve) => server.close(() => resolve()));
    }
  });

  it("falls back to ss when lsof is unavailable", async () => {
    const server = net.createServer();
    const address = await listenServer(server, 0, "127.0.0.1");
    if (!address) {
      return;
    }
    const port = address.port;

    runCommandWithTimeoutMock.mockImplementation(async (argv: string[]) => {
      const command = argv[0];
      if (typeof command !== "string") {
        return { stdout: "", stderr: "", code: 1 };
      }
      if (command.includes("lsof")) {
        throw Object.assign(new Error("spawn lsof ENOENT"), { code: "ENOENT" });
      }
      if (command === "ss") {
        return {
          stdout: `LISTEN 0 511 127.0.0.1:${port} 0.0.0.0:* users:(("node",pid=${process.pid},fd=23))`,
          stderr: "",
          code: 0,
        };
      }
      if (command === "ps") {
        if (argv.includes("command=")) {
          return {
            stdout: "node /tmp/openclaw/dist/index.js gateway --port 18789\n",
            stderr: "",
            code: 0,
          };
        }
        if (argv.includes("user=")) {
          return {
            stdout: "debian\n",
            stderr: "",
            code: 0,
          };
        }
        if (argv.includes("ppid=")) {
          return {
            stdout: "1\n",
            stderr: "",
            code: 0,
          };
        }
      }
      return { stdout: "", stderr: "", code: 1 };
    });

    try {
      const result = await inspectPortUsage(port);
      expect(result.status).toBe("busy");
      expect(result.listeners.length).toBeGreaterThan(0);
      expect(result.listeners[0]?.pid).toBe(process.pid);
      expect(result.listeners[0]?.commandLine).toContain("openclaw");
      expect(result.errors).toBeUndefined();
    } finally {
      await new Promise<void>((resolve) => server.close(() => resolve()));
    }
  });
});