// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
import { chunkedBodyReader } from "../../../test_util/std/http/_io.ts";
import { BufReader, BufWriter } from "../../../test_util/std/io/bufio.ts";
import { Buffer } from "../../../test_util/std/io/buffer.ts";
import { TextProtoReader } from "../../../test_util/std/textproto/mod.ts";
import {
  assert,
  assertEquals,
  assertThrowsAsync,
  deferred,
  delay,
  unitTest,
} from "./test_util.ts";

async function writeRequestAndReadResponse(conn: Deno.Conn): Promise<string> {
  const encoder = new TextEncoder();
  const decoder = new TextDecoder();

  const w = new BufWriter(conn);
  const r = new BufReader(conn);
  const body = `GET / HTTP/1.1\r\nHost: 127.0.0.1:4501\r\n\r\n`;
  const writeResult = await w.write(encoder.encode(body));
  assertEquals(body.length, writeResult);
  await w.flush();
  const tpr = new TextProtoReader(r);
  const statusLine = await tpr.readLine();
  assert(statusLine !== null);
  const headers = await tpr.readMIMEHeader();
  assert(headers !== null);

  const chunkedReader = chunkedBodyReader(headers, r);
  const buf = new Uint8Array(5);
  const dest = new Buffer();
  let result: number | null;
  while ((result = await chunkedReader.read(buf)) !== null) {
    const len = Math.min(buf.byteLength, result);
    await dest.write(buf.subarray(0, len));
  }
  return decoder.decode(dest.bytes());
}

unitTest({ perms: { net: true } }, async function httpServerBasic() {
  const promise = (async () => {
    const listener = Deno.listen({ port: 4501 });
    for await (const conn of listener) {
      const httpConn = Deno.serveHttp(conn);
      for await (const { request, respondWith } of httpConn) {
        assertEquals(new URL(request.url).href, "http://127.0.0.1:4501/");
        assertEquals(await request.text(), "");
        respondWith(new Response("Hello World", { headers: { "foo": "bar" } }));
      }
      break;
    }
  })();

  const resp = await fetch("http://127.0.0.1:4501/", {
    headers: { "connection": "close" },
  });
  const clone = resp.clone();
  const text = await resp.text();
  assertEquals(text, "Hello World");
  assertEquals(resp.headers.get("foo"), "bar");
  const cloneText = await clone.text();
  assertEquals(cloneText, "Hello World");
  await promise;
});

unitTest(
  { perms: { net: true } },
  async function httpServerStreamResponse() {
    const stream = new TransformStream();
    const writer = stream.writable.getWriter();
    writer.write(new TextEncoder().encode("hello "));
    writer.write(new TextEncoder().encode("world"));
    writer.close();

    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const evt = await httpConn.nextRequest();
      assert(evt);
      const { request, respondWith } = evt;
      assert(!request.body);
      await respondWith(new Response(stream.readable));
      httpConn.close();
      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/");
    const respBody = await resp.text();
    assertEquals("hello world", respBody);
    await promise;
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerStreamRequest() {
    const stream = new TransformStream();
    const writer = stream.writable.getWriter();
    writer.write(new TextEncoder().encode("hello "));
    writer.write(new TextEncoder().encode("world"));
    writer.close();

    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const evt = await httpConn.nextRequest();
      assert(evt);
      const { request, respondWith } = evt;
      const reqBody = await request.text();
      assertEquals("hello world", reqBody);
      await respondWith(new Response(""));

      // TODO(ry) If we don't call httpConn.nextRequest() here we get "error sending
      // request for url (https://localhost:4501/): connection closed before
      // message completed".
      assertEquals(await httpConn.nextRequest(), null);

      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/", {
      body: stream.readable,
      method: "POST",
      headers: { "connection": "close" },
    });

    await resp.arrayBuffer();
    await promise;
  },
);

unitTest({ perms: { net: true } }, async function httpServerStreamDuplex() {
  const promise = (async () => {
    const listener = Deno.listen({ port: 4501 });
    const conn = await listener.accept();
    const httpConn = Deno.serveHttp(conn);
    const evt = await httpConn.nextRequest();
    assert(evt);
    const { request, respondWith } = evt;
    assert(request.body);
    await respondWith(new Response(request.body));
    httpConn.close();
    listener.close();
  })();

  const ts = new TransformStream();
  const writable = ts.writable.getWriter();
  const resp = await fetch("http://127.0.0.1:4501/", {
    method: "POST",
    body: ts.readable,
  });
  assert(resp.body);
  const reader = resp.body.getReader();
  await writable.write(new Uint8Array([1]));
  const chunk1 = await reader.read();
  assert(!chunk1.done);
  assertEquals(chunk1.value, new Uint8Array([1]));
  await writable.write(new Uint8Array([2]));
  const chunk2 = await reader.read();
  assert(!chunk2.done);
  assertEquals(chunk2.value, new Uint8Array([2]));
  await writable.close();
  const chunk3 = await reader.read();
  assert(chunk3.done);
  await promise;
});

unitTest({ perms: { net: true } }, async function httpServerClose() {
  const listener = Deno.listen({ port: 4501 });
  const client = await Deno.connect({ port: 4501 });
  const httpConn = Deno.serveHttp(await listener.accept());
  client.close();
  const evt = await httpConn.nextRequest();
  assertEquals(evt, null);
  // Note httpConn is automatically closed when "done" is reached.
  listener.close();
});

unitTest({ perms: { net: true } }, async function httpServerInvalidMethod() {
  const listener = Deno.listen({ port: 4501 });
  const client = await Deno.connect({ port: 4501 });
  const httpConn = Deno.serveHttp(await listener.accept());
  await client.write(new Uint8Array([1, 2, 3]));
  await assertThrowsAsync(
    async () => {
      await httpConn.nextRequest();
    },
    Deno.errors.Http,
    "invalid HTTP method parsed",
  );
  // Note httpConn is automatically closed when it errors.
  client.close();
  listener.close();
});

unitTest(
  { perms: { read: true, net: true } },
  async function httpServerWithTls(): Promise<void> {
    const hostname = "localhost";
    const port = 4501;

    const promise = (async () => {
      const listener = Deno.listenTls({
        hostname,
        port,
        certFile: "cli/tests/tls/localhost.crt",
        keyFile: "cli/tests/tls/localhost.key",
      });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const evt = await httpConn.nextRequest();
      assert(evt);
      const { respondWith } = evt;
      await respondWith(new Response("Hello World"));

      // TODO(ry) If we don't call httpConn.nextRequest() here we get "error sending
      // request for url (https://localhost:4501/): connection closed before
      // message completed".
      assertEquals(await httpConn.nextRequest(), null);

      listener.close();
    })();

    const caData = Deno.readTextFileSync("cli/tests/tls/RootCA.pem");
    const client = Deno.createHttpClient({ caData });
    const resp = await fetch(`https://${hostname}:${port}/`, {
      client,
      headers: { "connection": "close" },
    });
    const respBody = await resp.text();
    assertEquals("Hello World", respBody);
    await promise;
    client.close();
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerRegressionHang() {
    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const event = await httpConn.nextRequest();
      assert(event);
      const { request, respondWith } = event;
      const reqBody = await request.text();
      assertEquals("request", reqBody);
      await respondWith(new Response("response"));
      httpConn.close();
      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/", {
      method: "POST",
      body: "request",
    });
    const respBody = await resp.text();
    assertEquals("response", respBody);
    await promise;
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerCancelBodyOnResponseFailure() {
    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const event = await httpConn.nextRequest();
      assert(event);
      const { respondWith } = event;
      let cancelReason = null;
      const responseError = await assertThrowsAsync(
        async () => {
          let interval = 0;
          await respondWith(
            new Response(
              new ReadableStream({
                start(controller) {
                  interval = setInterval(() => {
                    const message = `data: ${Date.now()}\n\n`;
                    controller.enqueue(new TextEncoder().encode(message));
                  }, 200);
                },
                cancel(reason) {
                  cancelReason = reason;
                  clearInterval(interval);
                },
              }),
            ),
          );
        },
        Deno.errors.Http,
      );
      assertEquals(cancelReason, responseError);
      httpConn.close();
      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/");
    await resp.body!.cancel();
    await promise;
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerNextRequestErrorExposedInResponse() {
    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const event = await httpConn.nextRequest();
      assert(event);
      // Start polling for the next request before awaiting response.
      const nextRequestPromise = httpConn.nextRequest();
      const { respondWith } = event;
      await assertThrowsAsync(
        async () => {
          let interval = 0;
          await respondWith(
            new Response(
              new ReadableStream({
                start(controller) {
                  interval = setInterval(() => {
                    const message = `data: ${Date.now()}\n\n`;
                    controller.enqueue(new TextEncoder().encode(message));
                  }, 200);
                },
                cancel() {
                  clearInterval(interval);
                },
              }),
            ),
          );
        },
        Deno.errors.Http,
        "connection closed",
      );
      // The error from `op_http_request_next` reroutes to `respondWith()`.
      assertEquals(await nextRequestPromise, null);
      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/");
    await resp.body!.cancel();
    await promise;
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerEmptyBlobResponse() {
    const promise = (async () => {
      const listener = Deno.listen({ port: 4501 });
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const event = await httpConn.nextRequest();
      assert(event);
      const { respondWith } = event;
      await respondWith(new Response(new Blob([])));
      httpConn.close();
      listener.close();
    })();

    const resp = await fetch("http://127.0.0.1:4501/");
    const respBody = await resp.text();
    assertEquals("", respBody);
    await promise;
  },
);

unitTest(
  { perms: { net: true } },
  async function httpServerNextRequestResolvesOnClose() {
    const httpConnList: Deno.HttpConn[] = [];

    async function serve(l: Deno.Listener) {
      for await (const conn of l) {
        (async () => {
          const c = Deno.serveHttp(conn);
          httpConnList.push(c);
          for await (const { respondWith } of c) {
            respondWith(new Response("hello"));
          }
        })();
      }
    }

    const l = Deno.listen({ port: 4500 });
    serve(l);

    await delay(300);
    const res = await fetch("http://localhost:4500/");
    const _text = await res.text();

    // Close connection and listener.
    httpConnList.forEach((conn) => conn.close());
    l.close();

    await delay(300);
  },
);

unitTest(
  { perms: { net: true } },
  // Issue: https://github.com/denoland/deno/issues/10870
  async function httpServerHang() {
    // Quick and dirty way to make a readable stream from a string. Alternatively,
    // `readableStreamFromReader(file)` could be used.
    function stream(s: string): ReadableStream<Uint8Array> {
      return new Response(s).body!;
    }

    const httpConns: Deno.HttpConn[] = [];
    const promise = (async () => {
      let count = 0;
      const listener = Deno.listen({ port: 4501 });
      for await (const conn of listener) {
        (async () => {
          const httpConn = Deno.serveHttp(conn);
          httpConns.push(httpConn);
          for await (const { respondWith } of httpConn) {
            respondWith(new Response(stream("hello")));

            count++;
            if (count >= 2) {
              listener.close();
            }
          }
        })();
      }
    })();

    const clientConn = await Deno.connect({ port: 4501 });

    const r1 = await writeRequestAndReadResponse(clientConn);
    assertEquals(r1, "hello");

    const r2 = await writeRequestAndReadResponse(clientConn);
    assertEquals(r2, "hello");

    clientConn.close();
    await promise;
    for (const conn of httpConns) {
      conn.close();
    }
  },
);

unitTest(
  { perms: { net: true } },
  // Issue: https://github.com/denoland/deno/issues/10930
  async function httpServerStreamingResponse() {
    // This test enqueues a single chunk for readable
    // stream and waits for client to read that chunk and signal
    // it before enqueueing subsequent chunk. Issue linked above
    // presented a situation where enqueued chunks were not
    // written to the HTTP connection until the next chunk was enqueued.

    let counter = 0;

    const deferreds = [
      deferred(),
      deferred(),
      deferred(),
    ];

    async function writeRequest(conn: Deno.Conn) {
      const encoder = new TextEncoder();
      const decoder = new TextDecoder();

      const w = new BufWriter(conn);
      const r = new BufReader(conn);
      const body = `GET / HTTP/1.1\r\nHost: 127.0.0.1:4501\r\n\r\n`;
      const writeResult = await w.write(encoder.encode(body));
      assertEquals(body.length, writeResult);
      await w.flush();
      const tpr = new TextProtoReader(r);
      const statusLine = await tpr.readLine();
      assert(statusLine !== null);
      const headers = await tpr.readMIMEHeader();
      assert(headers !== null);

      const chunkedReader = chunkedBodyReader(headers, r);
      const buf = new Uint8Array(5);
      const dest = new Buffer();
      let result: number | null;
      while ((result = await chunkedReader.read(buf)) !== null) {
        const len = Math.min(buf.byteLength, result);
        await dest.write(buf.subarray(0, len));
        // Resolve a deferred - this will make response stream to
        // enqueue next chunk.
        deferreds[counter - 1].resolve();
      }
      return decoder.decode(dest.bytes());
    }

    function periodicStream() {
      return new ReadableStream({
        start(controller) {
          controller.enqueue(`${counter}\n`);
          counter++;
        },

        async pull(controller) {
          if (counter >= 3) {
            return controller.close();
          }

          await deferreds[counter - 1];

          controller.enqueue(`${counter}\n`);
          counter++;
        },
      }).pipeThrough(new TextEncoderStream());
    }

    const listener = Deno.listen({ port: 4501 });
    const finished = (async () => {
      const conn = await listener.accept();
      const httpConn = Deno.serveHttp(conn);
      const requestEvent = await httpConn.nextRequest();
      const { respondWith } = requestEvent!;
      await respondWith(new Response(periodicStream()));
      httpConn.close();
    })();

    // start a client
    const clientConn = await Deno.connect({ port: 4501 });

    const r1 = await writeRequest(clientConn);
    assertEquals(r1, "0\n1\n2\n");

    await finished;
    clientConn.close();
    listener.close();
  },
);