// Proxy capture server tests cover request recording and response handling.
import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
import {
  request as httpRequest,
  createServer as createHttpServer,
  type IncomingMessage,
} from "node:http";
import net, { type AddressInfo } from "node:net";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { afterEach, describe, expect, it, vi } from "vitest";
import { closeOpenClawStateDatabaseForTest } from "../state/openclaw-state-db.js";
import type { DebugProxySettings } from "./env.js";
import { startDebugProxyServer } from "./proxy-server.js";
import { closeDebugProxyCaptureStore, getDebugProxyCaptureStore } from "./store.sqlite.js";

let testRoot: string | undefined;
const originalStateDir = process.env.OPENCLAW_STATE_DIR;

async function cleanupTestRoot(): Promise<void> {
  closeDebugProxyCaptureStore();
  closeOpenClawStateDatabaseForTest();
  if (originalStateDir === undefined) {
    delete process.env.OPENCLAW_STATE_DIR;
  } else {
    process.env.OPENCLAW_STATE_DIR = originalStateDir;
  }
  if (!testRoot) {
    return;
  }
  const root = testRoot;
  testRoot = undefined;
  await rm(root, { recursive: true, force: true });
}

async function makeSettings(): Promise<DebugProxySettings> {
  testRoot = await mkdtemp(join(tmpdir(), "openclaw-debug-proxy-server-"));
  const certDir = join(testRoot, "certs");
  await mkdir(certDir, { recursive: true });
  await writeFile(join(certDir, "root-ca.pem"), "test root cert\n", "utf8");
  await writeFile(join(certDir, "root-ca-key.pem"), "test root key\n", "utf8");
  process.env.OPENCLAW_STATE_DIR = testRoot;
  return {
    enabled: true,
    required: false,
    dbPath: join(testRoot, "capture.sqlite"),
    blobDir: join(testRoot, "blobs"),
    certDir,
    sessionId: "debug-proxy-server-test",
    sourceProcess: "test",
  };
}

async function startLargeBodyOrigin(responseBody: string): Promise<{
  receivedRequestBody: () => string;
  responseBody: string;
  stop: () => Promise<void>;
  url: string;
}> {
  let receivedBody = "";
  const server = createHttpServer((req, res) => {
    req.setEncoding("utf8");
    req.on("data", (chunk) => {
      receivedBody += chunk;
    });
    req.on("end", () => {
      res.writeHead(200, {
        "content-length": Buffer.byteLength(responseBody),
        "content-type": "text/plain; charset=utf-8",
      });
      res.end(responseBody);
    });
  });
  await new Promise<void>((resolve, reject) => {
    server.once("error", reject);
    server.listen(0, "127.0.0.1", () => {
      server.off("error", reject);
      resolve();
    });
  });
  const address = server.address() as AddressInfo;
  return {
    receivedRequestBody: () => receivedBody,
    responseBody,
    stop: async () =>
      await new Promise<void>((resolve, reject) => {
        server.close((error) => {
          if (error) {
            reject(error);
            return;
          }
          resolve();
        });
      }),
    url: `http://127.0.0.1:${address.port}/capture`,
  };
}

async function startResponseErrorOrigin(): Promise<{
  stop: () => Promise<void>;
  url: string;
}> {
  const server = createHttpServer((req, res) => {
    if (req.url === "/before-headers") {
      res.socket?.destroy();
      return;
    }
    if (req.url === "/after-headers") {
      res.writeHead(200, { "content-type": "text/plain; charset=utf-8" });
      res.flushHeaders();
      res.write("partial");
      setTimeout(() => res.socket?.destroy(), 50);
      return;
    }
    res.writeHead(200, {
      "content-length": 2,
      "content-type": "text/plain; charset=utf-8",
    });
    res.end("ok");
  });
  await new Promise<void>((resolve, reject) => {
    server.once("error", reject);
    server.listen(0, "127.0.0.1", () => {
      server.off("error", reject);
      resolve();
    });
  });
  const address = server.address() as AddressInfo;
  return {
    stop: async () =>
      await new Promise<void>((resolve, reject) => {
        server.close((error) => {
          if (error) {
            reject(error);
            return;
          }
          resolve();
        });
      }),
    url: `http://127.0.0.1:${address.port}`,
  };
}

type ProxyResponseResult = {
  body: string;
  complete: boolean;
  errorMessage?: string;
  statusCode?: number;
};

async function getThroughProxy(proxyUrl: string, targetUrl: string): Promise<ProxyResponseResult> {
  const proxy = new URL(proxyUrl);
  return await new Promise<ProxyResponseResult>((resolve) => {
    let settled = false;
    let body = "";
    let response: IncomingMessage | undefined;
    const finish = (error?: Error) => {
      if (settled) {
        return;
      }
      settled = true;
      resolve({
        body,
        complete: response?.complete ?? false,
        ...(error ? { errorMessage: error.message } : {}),
        ...(response?.statusCode === undefined ? {} : { statusCode: response.statusCode }),
      });
    };
    const req = httpRequest(
      {
        host: proxy.hostname,
        port: Number(proxy.port),
        method: "GET",
        path: targetUrl,
        headers: { connection: "close" },
      },
      (res) => {
        response = res;
        res.setEncoding("utf8");
        res.on("data", (chunk) => {
          body += chunk;
        });
        res.on("end", () => finish());
        res.on("error", finish);
        res.on("close", () => {
          if (!res.complete) {
            finish(new Error("response closed before completion"));
          }
        });
      },
    );
    req.on("error", finish);
    req.end();
  });
}

async function postThroughProxy(params: {
  body: string;
  proxyUrl: string;
  targetUrl: string;
}): Promise<string> {
  const proxy = new URL(params.proxyUrl);
  return await new Promise<string>((resolve, reject) => {
    const req = httpRequest(
      {
        host: proxy.hostname,
        port: Number(proxy.port),
        method: "POST",
        path: params.targetUrl,
        headers: {
          connection: "close",
          "content-length": Buffer.byteLength(params.body),
          "content-type": "text/plain; charset=utf-8",
        },
      },
      (res) => {
        const chunks: Buffer[] = [];
        res.on("data", (chunk) => {
          chunks.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk));
        });
        res.on("end", () => {
          resolve(Buffer.concat(chunks).toString("utf8"));
        });
      },
    );
    req.on("error", reject);
    req.end(params.body);
  });
}

type StreamingProxyOrigin = {
  state: {
    closedResponses: number;
    drainWaits: number;
    finishedResponses: number;
    queuedBytes: number;
  };
  stop: () => Promise<void>;
  url: string;
};

async function startStreamingProxyOrigin(responseBodyBytes: number): Promise<StreamingProxyOrigin> {
  const state = {
    closedResponses: 0,
    drainWaits: 0,
    finishedResponses: 0,
    queuedBytes: 0,
  };
  const chunk = Buffer.alloc(64 * 1024, "x");
  const server = createHttpServer((req, res) => {
    req.resume();
    if (req.url === "/healthy") {
      res.writeHead(200, {
        "content-length": 2,
        "content-type": "text/plain; charset=utf-8",
      });
      res.end("ok");
      return;
    }

    res.writeHead(200, {
      "content-length": responseBodyBytes,
      "content-type": "text/plain; charset=utf-8",
    });
    res.on("close", () => {
      state.closedResponses++;
    });
    res.on("finish", () => {
      state.finishedResponses++;
    });

    const writeNextChunk = () => {
      while (state.queuedBytes < responseBodyBytes && !res.destroyed) {
        const chunkBytes = Math.min(chunk.byteLength, responseBodyBytes - state.queuedBytes);
        state.queuedBytes += chunkBytes;
        if (!res.write(chunk.subarray(0, chunkBytes))) {
          state.drainWaits++;
          res.once("drain", writeNextChunk);
          return;
        }
      }
      if (state.queuedBytes === responseBodyBytes && !res.destroyed) {
        res.end();
      }
    };
    writeNextChunk();
  });

  await new Promise<void>((resolve, reject) => {
    server.once("error", reject);
    server.listen(0, "127.0.0.1", () => {
      server.off("error", reject);
      resolve();
    });
  });
  const address = server.address() as AddressInfo;
  return {
    state,
    stop: async () =>
      await new Promise<void>((resolve, reject) => {
        server.close((error) => {
          if (error) {
            reject(error);
            return;
          }
          resolve();
        });
      }),
    url: `http://127.0.0.1:${address.port}`,
  };
}

async function rawSlowGetThroughProxy(params: {
  abortAfterBytes?: number;
  abortWithReset?: boolean;
  onResume?: () => void;
  pauseBeforeReadMs: number;
  proxyUrl: string;
  targetUrl: string;
}): Promise<{
  aborted: boolean;
  bodyBytes: number;
  receivedBytes: number;
  resumed: boolean;
  statusLine: string;
}> {
  const proxy = new URL(params.proxyUrl);
  return await new Promise((resolve, reject) => {
    let aborted = false;
    let bodyBytes = 0;
    let contentLength: number | undefined;
    let headerBytes = Buffer.alloc(0);
    let receivedBytes = 0;
    let resumed = false;
    let settled = false;
    let statusLine = "";
    let resumeTimeout: ReturnType<typeof setTimeout> | undefined;
    const socket = net.connect(Number(proxy.port), proxy.hostname);
    const timeout = setTimeout(() => {
      socket.destroy();
      if (!settled) {
        settled = true;
        reject(new Error("slow proxy client timed out"));
      }
    }, 15000);
    const finish = () => {
      clearTimeout(timeout);
      clearTimeout(resumeTimeout);
      if (!settled) {
        settled = true;
        resolve({ aborted, bodyBytes, receivedBytes, resumed, statusLine });
      }
    };
    const maybeFinishCompleteBody = () => {
      if (contentLength !== undefined && bodyBytes >= contentLength) {
        socket.destroy();
        finish();
      }
    };
    socket.on("connect", () => {
      socket.write(
        `GET ${params.targetUrl} HTTP/1.1\r\nHost: 127.0.0.1\r\nConnection: close\r\n\r\n`,
      );
      socket.pause();
      resumeTimeout = setTimeout(() => {
        resumed = true;
        params.onResume?.();
        socket.resume();
      }, params.pauseBeforeReadMs);
    });
    socket.on("data", (chunk) => {
      receivedBytes += chunk.length;
      if (contentLength === undefined) {
        headerBytes = Buffer.concat([headerBytes, Buffer.from(chunk)]);
        const headerEnd = headerBytes.indexOf("\r\n\r\n");
        if (headerEnd === -1) {
          return;
        }
        const headerText = headerBytes.subarray(0, headerEnd).toString("latin1");
        statusLine = headerText.split("\r\n")[0] ?? "";
        const contentLengthHeader = headerText
          .split("\r\n")
          .find((line) => line.toLowerCase().startsWith("content-length:"));
        const parsedContentLength = Number(contentLengthHeader?.split(":")[1]?.trim());
        contentLength = Number.isFinite(parsedContentLength) ? parsedContentLength : 0;
        bodyBytes += headerBytes.byteLength - headerEnd - 4;
        headerBytes = Buffer.alloc(0);
      } else {
        bodyBytes += chunk.length;
      }
      if (params.abortAfterBytes !== undefined && bodyBytes >= params.abortAfterBytes) {
        aborted = true;
        if (params.abortWithReset) {
          socket.resetAndDestroy();
        } else {
          socket.destroy();
        }
        finish();
        return;
      }
      maybeFinishCompleteBody();
    });
    socket.on("error", (error) => {
      clearTimeout(timeout);
      clearTimeout(resumeTimeout);
      if (!settled) {
        settled = true;
        reject(error);
      }
    });
    socket.on("close", finish);
  });
}

afterEach(async () => {
  await cleanupTestRoot();
});

describe("startDebugProxyServer", () => {
  it("caps UTF-8 previews on character boundaries while forwarding full bodies", async () => {
    const settings = await makeSettings();
    const origin = await startLargeBodyOrigin(`${"r".repeat(8191)}😀tail`);
    const proxy = await startDebugProxyServer({ settings });
    const requestBody = `${"q".repeat(8191)}étail`;

    try {
      const responseBody = await postThroughProxy({
        body: requestBody,
        proxyUrl: proxy.proxyUrl,
        targetUrl: origin.url,
      });

      expect(origin.receivedRequestBody()).toBe(requestBody);
      expect(responseBody).toBe(origin.responseBody);
      const events = getDebugProxyCaptureStore().getSessionEvents(settings.sessionId, 10);
      const capturedRequest = events.find((event) => event.kind === "request");
      const capturedResponse = events.find((event) => event.kind === "response");
      expect(capturedRequest?.dataText).toBe("q".repeat(8191));
      expect(capturedResponse?.dataText).toBe("r".repeat(8191));
      expect(JSON.parse(String(capturedRequest?.metaJson))).toMatchObject({
        bodyBytes: Buffer.byteLength(requestBody),
        capturePreviewBytes: 8192,
        captureTruncated: true,
      });
      expect(JSON.parse(String(capturedResponse?.metaJson))).toMatchObject({
        bodyBytes: Buffer.byteLength(origin.responseBody),
        capturePreviewBytes: 8192,
        captureTruncated: true,
      });
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });

  it("pauses the upstream response while downstream forwarding is backpressured", async () => {
    const settings = await makeSettings();
    const responseBodyBytes = 16 * 1024 * 1024;
    const origin = await startStreamingProxyOrigin(responseBodyBytes);
    const proxy = await startDebugProxyServer({ settings });
    let queuedBytesAtResume = 0;

    try {
      const forwarded = await rawSlowGetThroughProxy({
        onResume: () => {
          queuedBytesAtResume = origin.state.queuedBytes;
        },
        pauseBeforeReadMs: 150,
        proxyUrl: proxy.proxyUrl,
        targetUrl: `${origin.url}/capture`,
      });

      expect(forwarded).toMatchObject({
        aborted: false,
        bodyBytes: responseBodyBytes,
        resumed: true,
        statusLine: "HTTP/1.1 200 OK",
      });
      expect(queuedBytesAtResume).toBeLessThan(responseBodyBytes);
      expect(origin.state.drainWaits).toBeGreaterThan(0);
      expect(origin.state.queuedBytes).toBe(responseBodyBytes);
      const captureEvents = getDebugProxyCaptureStore()
        .getSessionEvents(settings.sessionId, 20)
        .filter((event) => event.path === "/capture");
      expect(captureEvents.filter((event) => event.kind === "error")).toEqual([]);
      expect(captureEvents.filter((event) => event.kind === "response")).toEqual([
        expect.objectContaining({ direction: "inbound", status: 200 }),
      ]);
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });

  it("closes the upstream response when a slow downstream client aborts", async () => {
    const settings = await makeSettings();
    const responseBodyBytes = 16 * 1024 * 1024;
    const origin = await startStreamingProxyOrigin(responseBodyBytes);
    const proxy = await startDebugProxyServer({ settings });

    try {
      const aborted = await rawSlowGetThroughProxy({
        abortAfterBytes: 64 * 1024,
        pauseBeforeReadMs: 0,
        proxyUrl: proxy.proxyUrl,
        targetUrl: `${origin.url}/capture`,
      });

      expect(aborted).toMatchObject({
        aborted: true,
        resumed: true,
        statusLine: "HTTP/1.1 200 OK",
      });
      expect(aborted.bodyBytes).toBeGreaterThanOrEqual(64 * 1024);

      await vi.waitFor(() => {
        expect(origin.state.closedResponses).toBe(1);
        expect(origin.state.finishedResponses).toBe(0);
        const captureEvents = getDebugProxyCaptureStore()
          .getSessionEvents(settings.sessionId, 20)
          .filter((event) => event.path === "/capture");
        const capturedRequest = captureEvents.find((event) => event.kind === "request");
        expect(capturedRequest).toBeDefined();
        expect(captureEvents.filter((event) => event.kind === "error")).toEqual([
          expect.objectContaining({
            direction: "local",
            errorText: "Downstream response closed before completion",
            flowId: capturedRequest?.flowId,
          }),
        ]);
        expect(captureEvents.filter((event) => event.kind === "response")).toEqual([]);
      });

      const healthy = await getThroughProxy(proxy.proxyUrl, `${origin.url}/healthy`);
      expect(healthy).toMatchObject({ body: "ok", complete: true, statusCode: 200 });
      expect(
        getDebugProxyCaptureStore()
          .getSessionEvents(settings.sessionId, 20)
          .filter((event) => event.path === "/healthy" && event.kind === "error"),
      ).toEqual([]);
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });

  it("records a reset downstream client as exactly one local capture error", async () => {
    const settings = await makeSettings();
    const origin = await startStreamingProxyOrigin(16 * 1024 * 1024);
    const proxy = await startDebugProxyServer({ settings });

    try {
      const aborted = await rawSlowGetThroughProxy({
        abortAfterBytes: 64 * 1024,
        abortWithReset: true,
        pauseBeforeReadMs: 0,
        proxyUrl: proxy.proxyUrl,
        targetUrl: `${origin.url}/capture`,
      });

      expect(aborted).toMatchObject({
        aborted: true,
        resumed: true,
        statusLine: "HTTP/1.1 200 OK",
      });

      await vi.waitFor(() => {
        expect(origin.state.closedResponses).toBe(1);
        expect(origin.state.finishedResponses).toBe(0);
        const captureEvents = getDebugProxyCaptureStore()
          .getSessionEvents(settings.sessionId, 20)
          .filter((event) => event.path === "/capture");
        const capturedRequest = captureEvents.find((event) => event.kind === "request");
        expect(capturedRequest).toBeDefined();
        expect(captureEvents.filter((event) => event.kind === "error")).toEqual([
          expect.objectContaining({
            direction: "local",
            errorText: expect.any(String),
            flowId: capturedRequest?.flowId,
          }),
        ]);
        expect(captureEvents.filter((event) => event.kind === "response")).toEqual([]);
      });

      const healthy = await getThroughProxy(proxy.proxyUrl, `${origin.url}/healthy`);
      expect(healthy).toMatchObject({ body: "ok", complete: true, statusCode: 200 });
      expect(
        getDebugProxyCaptureStore()
          .getSessionEvents(settings.sessionId, 20)
          .filter((event) => event.path === "/healthy" && event.kind === "error"),
      ).toEqual([]);
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });

  it("returns a complete 502 and survives an upstream failure before response headers", async () => {
    const settings = await makeSettings();
    const origin = await startResponseErrorOrigin();
    const proxy = await startDebugProxyServer({ settings });

    try {
      const failed = await getThroughProxy(proxy.proxyUrl, `${origin.url}/before-headers`);
      expect(failed).toMatchObject({
        body: "Bad Gateway\n",
        complete: true,
        statusCode: 502,
      });

      const healthy = await getThroughProxy(proxy.proxyUrl, `${origin.url}/healthy`);
      expect(healthy).toMatchObject({ body: "ok", complete: true, statusCode: 200 });
      expect(getDebugProxyCaptureStore().getSessionEvents(settings.sessionId, 20)).toContainEqual(
        expect.objectContaining({ direction: "local", kind: "error" }),
      );
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });

  it("aborts a partial response after headers and survives the upstream stream error", async () => {
    const settings = await makeSettings();
    const origin = await startResponseErrorOrigin();
    const proxy = await startDebugProxyServer({ settings });

    try {
      const failed = await getThroughProxy(proxy.proxyUrl, `${origin.url}/after-headers`);
      expect(failed).toMatchObject({
        body: "partial",
        complete: false,
        statusCode: 200,
      });
      expect(failed.errorMessage).toBeDefined();

      const healthy = await getThroughProxy(proxy.proxyUrl, `${origin.url}/healthy`);
      expect(healthy).toMatchObject({ body: "ok", complete: true, statusCode: 200 });
      expect(getDebugProxyCaptureStore().getSessionEvents(settings.sessionId, 20)).toContainEqual(
        expect.objectContaining({ direction: "inbound", kind: "error" }),
      );
    } finally {
      await proxy.stop();
      await origin.stop();
    }
  });
});