import {
  AssertionError,
  assertThrowsAsync,
  assertEquals,
  assert,
  assertNotEOF,
  assertNotEquals,
} from "../testing/asserts.ts";
import {
  bodyReader,
  writeTrailers,
  readTrailers,
  parseHTTPVersion,
  readRequest,
  writeResponse,
} from "./io.ts";
import { encode, decode } from "../strings/mod.ts";
import { BufReader, ReadLineResult } from "../io/bufio.ts";
import { chunkedBodyReader } from "./io.ts";
import { ServerRequest, Response } from "./server.ts";
import { StringReader } from "../io/readers.ts";
import { mockConn } from "./mock.ts";
const { Buffer, test } = Deno;

test("bodyReader", async () => {
  const text = "Hello, Deno";
  const r = bodyReader(text.length, new BufReader(new Buffer(encode(text))));
  assertEquals(decode(await Deno.readAll(r)), text);
});
function chunkify(n: number, char: string): string {
  const v = Array.from({ length: n })
    .map(() => `${char}`)
    .join("");
  return `${n.toString(16)}\r\n${v}\r\n`;
}
test("chunkedBodyReader", async () => {
  const body = [
    chunkify(3, "a"),
    chunkify(5, "b"),
    chunkify(11, "c"),
    chunkify(22, "d"),
    chunkify(0, ""),
  ].join("");
  const h = new Headers();
  const r = chunkedBodyReader(h, new BufReader(new Buffer(encode(body))));
  let result: number | Deno.EOF;
  // Use small buffer as some chunks exceed buffer size
  const buf = new Uint8Array(5);
  const dest = new Buffer();
  while ((result = await r.read(buf)) !== Deno.EOF) {
    const len = Math.min(buf.byteLength, result);
    await dest.write(buf.subarray(0, len));
  }
  const exp = "aaabbbbbcccccccccccdddddddddddddddddddddd";
  assertEquals(dest.toString(), exp);
});

test("chunkedBodyReader with trailers", async () => {
  const body = [
    chunkify(3, "a"),
    chunkify(5, "b"),
    chunkify(11, "c"),
    chunkify(22, "d"),
    chunkify(0, ""),
    "deno: land\r\n",
    "node: js\r\n",
    "\r\n",
  ].join("");
  const h = new Headers({
    trailer: "deno,node",
  });
  const r = chunkedBodyReader(h, new BufReader(new Buffer(encode(body))));
  assertEquals(h.has("trailer"), true);
  assertEquals(h.has("deno"), false);
  assertEquals(h.has("node"), false);
  const act = decode(await Deno.readAll(r));
  const exp = "aaabbbbbcccccccccccdddddddddddddddddddddd";
  assertEquals(act, exp);
  assertEquals(h.has("trailer"), false);
  assertEquals(h.get("deno"), "land");
  assertEquals(h.get("node"), "js");
});

test("readTrailers", async () => {
  const h = new Headers({
    trailer: "deno,node",
  });
  const trailer = ["deno: land", "node: js", "", ""].join("\r\n");
  await readTrailers(h, new BufReader(new Buffer(encode(trailer))));
  assertEquals(h.has("trailer"), false);
  assertEquals(h.get("deno"), "land");
  assertEquals(h.get("node"), "js");
});

test("readTrailer should throw if undeclared headers found in trailer", async () => {
  const patterns = [
    ["deno,node", "deno: land\r\nnode: js\r\ngo: lang\r\n\r\n"],
    ["deno", "node: js\r\n\r\n"],
    ["deno", "node:js\r\ngo: lang\r\n\r\n"],
  ];
  for (const [header, trailer] of patterns) {
    const h = new Headers({
      trailer: header,
    });
    await assertThrowsAsync(
      async () => {
        await readTrailers(h, new BufReader(new Buffer(encode(trailer))));
      },
      Error,
      "Undeclared trailer field"
    );
  }
});

test("readTrailer should throw if trailer contains prohibited fields", async () => {
  for (const f of ["content-length", "trailer", "transfer-encoding"]) {
    const h = new Headers({
      trailer: f,
    });
    await assertThrowsAsync(
      async () => {
        await readTrailers(h, new BufReader(new Buffer()));
      },
      Error,
      "Prohibited field for trailer"
    );
  }
});

test("writeTrailer", async () => {
  const w = new Buffer();
  await writeTrailers(
    w,
    new Headers({ "transfer-encoding": "chunked", trailer: "deno,node" }),
    new Headers({ deno: "land", node: "js" })
  );
  assertEquals(w.toString(), "deno: land\r\nnode: js\r\n\r\n");
});

test("writeTrailer should throw", async () => {
  const w = new Buffer();
  await assertThrowsAsync(
    () => {
      return writeTrailers(w, new Headers(), new Headers());
    },
    Error,
    'must have "trailer"'
  );
  await assertThrowsAsync(
    () => {
      return writeTrailers(w, new Headers({ trailer: "deno" }), new Headers());
    },
    Error,
    "only allowed"
  );
  for (const f of ["content-length", "trailer", "transfer-encoding"]) {
    await assertThrowsAsync(
      () => {
        return writeTrailers(
          w,
          new Headers({ "transfer-encoding": "chunked", trailer: f }),
          new Headers({ [f]: "1" })
        );
      },
      AssertionError,
      "prohibited"
    );
  }
  await assertThrowsAsync(
    () => {
      return writeTrailers(
        w,
        new Headers({ "transfer-encoding": "chunked", trailer: "deno" }),
        new Headers({ node: "js" })
      );
    },
    AssertionError,
    "Not trailer"
  );
});

// Ported from https://github.com/golang/go/blob/f5c43b9/src/net/http/request_test.go#L535-L565
test("parseHttpVersion", (): void => {
  const testCases = [
    { in: "HTTP/0.9", want: [0, 9] },
    { in: "HTTP/1.0", want: [1, 0] },
    { in: "HTTP/1.1", want: [1, 1] },
    { in: "HTTP/3.14", want: [3, 14] },
    { in: "HTTP", err: true },
    { in: "HTTP/one.one", err: true },
    { in: "HTTP/1.1/", err: true },
    { in: "HTTP/-1.0", err: true },
    { in: "HTTP/0.-1", err: true },
    { in: "HTTP/", err: true },
    { in: "HTTP/1,0", err: true },
  ];
  for (const t of testCases) {
    let r, err;
    try {
      r = parseHTTPVersion(t.in);
    } catch (e) {
      err = e;
    }
    if (t.err) {
      assert(err instanceof Error, t.in);
    } else {
      assertEquals(err, undefined);
      assertEquals(r, t.want, t.in);
    }
  }
});

test(async function writeUint8ArrayResponse(): Promise<void> {
  const shortText = "Hello";

  const body = new TextEncoder().encode(shortText);
  const res: Response = { body };

  const buf = new Deno.Buffer();
  await writeResponse(buf, res);

  const decoder = new TextDecoder("utf-8");
  const reader = new BufReader(buf);

  let r: ReadLineResult;
  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), "HTTP/1.1 200 OK");
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), `content-length: ${shortText.length}`);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(r.line.byteLength, 0);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), shortText);
  assertEquals(r.more, false);

  const eof = await reader.readLine();
  assertEquals(eof, Deno.EOF);
});

test(async function writeStringResponse(): Promise<void> {
  const body = "Hello";

  const res: Response = { body };

  const buf = new Deno.Buffer();
  await writeResponse(buf, res);

  const decoder = new TextDecoder("utf-8");
  const reader = new BufReader(buf);

  let r: ReadLineResult;
  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), "HTTP/1.1 200 OK");
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), `content-length: ${body.length}`);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(r.line.byteLength, 0);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), body);
  assertEquals(r.more, false);

  const eof = await reader.readLine();
  assertEquals(eof, Deno.EOF);
});

test(async function writeStringReaderResponse(): Promise<void> {
  const shortText = "Hello";

  const body = new StringReader(shortText);
  const res: Response = { body };

  const buf = new Deno.Buffer();
  await writeResponse(buf, res);

  const decoder = new TextDecoder("utf-8");
  const reader = new BufReader(buf);

  let r: ReadLineResult;
  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), "HTTP/1.1 200 OK");
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), "transfer-encoding: chunked");
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(r.line.byteLength, 0);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), shortText.length.toString());
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), shortText);
  assertEquals(r.more, false);

  r = assertNotEOF(await reader.readLine());
  assertEquals(decoder.decode(r.line), "0");
  assertEquals(r.more, false);
});

test("writeResponse with trailer", async () => {
  const w = new Buffer();
  const body = new StringReader("Hello");
  await writeResponse(w, {
    status: 200,
    headers: new Headers({
      "transfer-encoding": "chunked",
      trailer: "deno,node",
    }),
    body,
    trailers: () => new Headers({ deno: "land", node: "js" }),
  });
  const ret = w.toString();
  const exp = [
    "HTTP/1.1 200 OK",
    "transfer-encoding: chunked",
    "trailer: deno,node",
    "",
    "5",
    "Hello",
    "0",
    "",
    "deno: land",
    "node: js",
    "",
    "",
  ].join("\r\n");
  assertEquals(ret, exp);
});

test(async function readRequestError(): Promise<void> {
  const input = `GET / HTTP/1.1
malformedHeader
`;
  const reader = new BufReader(new StringReader(input));
  let err;
  try {
    await readRequest(mockConn(), reader);
  } catch (e) {
    err = e;
  }
  assert(err instanceof Error);
  assertEquals(err.message, "malformed MIME header line: malformedHeader");
});

// Ported from Go
// https://github.com/golang/go/blob/go1.12.5/src/net/http/request_test.go#L377-L443
// TODO(zekth) fix tests
test(async function testReadRequestError(): Promise<void> {
  const testCases = [
    {
      in: "GET / HTTP/1.1\r\nheader: foo\r\n\r\n",
      headers: [{ key: "header", value: "foo" }],
    },
    {
      in: "GET / HTTP/1.1\r\nheader:foo\r\n",
      err: Deno.errors.UnexpectedEof,
    },
    { in: "", err: Deno.EOF },
    {
      in: "HEAD / HTTP/1.1\r\nContent-Length:4\r\n\r\n",
      err: "http: method cannot contain a Content-Length",
    },
    {
      in: "HEAD / HTTP/1.1\r\n\r\n",
      headers: [],
    },
    // Multiple Content-Length values should either be
    // deduplicated if same or reject otherwise
    // See Issue 16490.
    {
      in:
        "POST / HTTP/1.1\r\nContent-Length: 10\r\nContent-Length: 0\r\n\r\n" +
        "Gopher hey\r\n",
      err: "cannot contain multiple Content-Length headers",
    },
    {
      in:
        "POST / HTTP/1.1\r\nContent-Length: 10\r\nContent-Length: 6\r\n\r\n" +
        "Gopher\r\n",
      err: "cannot contain multiple Content-Length headers",
    },
    {
      in:
        "PUT / HTTP/1.1\r\nContent-Length: 6 \r\nContent-Length: 6\r\n" +
        "Content-Length:6\r\n\r\nGopher\r\n",
      headers: [{ key: "Content-Length", value: "6" }],
    },
    {
      in: "PUT / HTTP/1.1\r\nContent-Length: 1\r\nContent-Length: 6 \r\n\r\n",
      err: "cannot contain multiple Content-Length headers",
    },
    // Setting an empty header is swallowed by textproto
    // see: readMIMEHeader()
    // {
    //   in: "POST / HTTP/1.1\r\nContent-Length:\r\nContent-Length: 3\r\n\r\n",
    //   err: "cannot contain multiple Content-Length headers"
    // },
    {
      in: "HEAD / HTTP/1.1\r\nContent-Length:0\r\nContent-Length: 0\r\n\r\n",
      headers: [{ key: "Content-Length", value: "0" }],
    },
    {
      in:
        "POST / HTTP/1.1\r\nContent-Length:0\r\ntransfer-encoding: " +
        "chunked\r\n\r\n",
      headers: [],
      err: "http: Transfer-Encoding and Content-Length cannot be send together",
    },
  ];
  for (const test of testCases) {
    const reader = new BufReader(new StringReader(test.in));
    let err;
    let req: ServerRequest | Deno.EOF | undefined;
    try {
      req = await readRequest(mockConn(), reader);
    } catch (e) {
      err = e;
    }
    if (test.err === Deno.EOF) {
      assertEquals(req, Deno.EOF);
    } else if (typeof test.err === "string") {
      assertEquals(err.message, test.err);
    } else if (test.err) {
      assert(err instanceof (test.err as typeof Deno.errors.UnexpectedEof));
    } else {
      assert(req instanceof ServerRequest);
      assert(test.headers);
      assertEquals(err, undefined);
      assertNotEquals(req, Deno.EOF);
      for (const h of test.headers) {
        assertEquals(req.headers.get(h.key), h.value);
      }
    }
  }
});