use crate::test_util::{
    assert_ends_with, assert_starts_with, check_elapsed, read_for, read_response, read_to_string,
    TestServer,
};
use servlin::{ContentType, Response};
use std::io::{Read, Write};
use std::time::{Duration, Instant};

mod test_util;

// TODO: Add a test for HttpError::BodyNotRead.  Decide what to do when client sends an unwanted body.

fn req_with_len(body_len: usize) -> String {
    format!("M / HTTP/1.1\r\ncontent-length:{body_len}\r\n\r\n")
        .chars()
        .chain(std::iter::repeat('a').take(body_len))
        .collect::<String>()
}

fn req_without_len(body_len: usize) -> String {
    "POST / HTTP/1.1\r\n\r\n"
        .chars()
        .chain(std::iter::repeat('a').take(body_len))
        .collect::<String>()
}

#[test]
fn panics() {
    let server = TestServer::start(|_req| panic!("ignore this panic")).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 500 Internal Server Error\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 12\r\n\r\nServer error",
    );
}

#[test]
fn empty() {
    let server = TestServer::start(|_req| Response::new(200)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 0\r\n\r\n",
    );
}

#[test]
fn unknown_code() {
    let server = TestServer::start(|_req| Response::new(9999)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 9999 Response\r\ncontent-length: 0\r\n\r\n",
    );
}

#[test]
fn text() {
    let server =
        TestServer::start(|_req| Response::text(200, "abc def\tghi\rjkl\nmno\r\npqr\r\n\r\nstu"))
            .unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 31\r\n\r\nabc def\tghi\rjkl\nmno\r\npqr\r\n\r\nstu",
    );
}

#[test]
fn with_status() {
    let server = TestServer::start(|_req| Response::new(200).with_status(201)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 201 Created\r\ncontent-length: 0\r\n\r\n",
    );
}

#[test]
fn with_type() {
    let server =
        TestServer::start(|_req| Response::new(200).with_type(ContentType::EventStream)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-type: text/event-stream\r\ncontent-length: 0\r\n\r\n",
    );
}

#[test]
fn with_type_and_body() {
    let server =
        TestServer::start(|_req| Response::text(200, "yo").with_type(ContentType::Markdown))
            .unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-type: text/markdown; charset=UTF-8\r\ncontent-length: 2\r\n\r\nyo",
    );
}

#[test]
fn with_body() {
    let server = TestServer::start(|_req| Response::new(200).with_body("abc")).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 3\r\n\r\nabc",
    );
}

#[test]
fn with_header() {
    let server =
        TestServer::start(|_req| Response::new(200).with_header("h1", "v1".try_into().unwrap()))
            .unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 0\r\nh1: v1\r\n\r\n",
    );
}

#[test]
fn with_duplicate_header() {
    let server = TestServer::start(|_req| {
        Response::new(200)
            .with_header("h1", "v1".try_into().unwrap())
            .with_header("h1", "v2".try_into().unwrap())
    })
    .unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 0\r\nh1: v1\r\nh1: v2\r\n\r\n",
    );
}

#[test]
fn with_duplicate_header_different_case() {
    let server = TestServer::start(|_req| {
        Response::new(200)
            .with_header("h1", "v1".try_into().unwrap())
            .with_header("H1", "v2".try_into().unwrap())
    })
    .unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 0\r\nh1: v1\r\nH1: v2\r\n\r\n",
    );
}

#[test]
fn method_not_allowed_405() {
    let server = TestServer::start(|_req| Response::method_not_allowed_405(&["GET"])).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 405 Method Not Allowed\r\ncontent-length: 0\r\nallow: GET\r\n\r\n",
    );
}

#[test]
fn duplicate_content_type_header() {
    let server = TestServer::start(|_req| {
        Response::text(200, "t1").with_header("Content-type", "text/plain".try_into().unwrap())
    })
    .unwrap();
    assert_starts_with(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 500 ",
    );
}

#[test]
fn duplicate_content_length_header() {
    let server =
        TestServer::start(|_req| Response::text(200, "t1").with_header("Content-length", 0.into()))
            .unwrap();
    assert_starts_with(
        server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(),
        "HTTP/1.1 500 ",
    );
}

#[test]
fn return_drop() {
    let server = TestServer::start(|_req| Response::drop_connection()).unwrap();
    assert_eq!(server.exchange("M / HTTP/1.1\r\n\r\n").unwrap(), "");
}

#[test]
fn get_body() {
    let server = TestServer::start(|req| {
        if req.body.is_pending() {
            Response::get_body_and_reprocess(70_000)
        } else {
            let len = req.body.reader().unwrap().bytes().count();
            Response::text(200, format!("len={len}"))
        }
    })
    .unwrap();
    // With content-length
    assert_ends_with(server.exchange(req_with_len(0)).unwrap(), "len=0");
    assert_ends_with(server.exchange(req_with_len(1)).unwrap(), "len=1");
    assert_ends_with(server.exchange(req_with_len(65_536)).unwrap(), "len=65536");
    assert_ends_with(server.exchange(req_with_len(65_537)).unwrap(), "len=65537");
    assert_ends_with(server.exchange(req_with_len(70_000)).unwrap(), "len=70000");
    assert_eq!(
        server.exchange(req_with_len(70_001)).unwrap(),
        "HTTP/1.1 413 Payload Too Large\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 25\r\n\r\nUploaded data is too big.",
    );

    // Without content-length
    assert_ends_with(server.exchange(req_without_len(0)).unwrap(), "len=0");
    assert_ends_with(server.exchange(req_without_len(1)).unwrap(), "len=1");
    assert_ends_with(
        server.exchange(req_without_len(65_536)).unwrap(),
        "len=65536",
    );
    assert_ends_with(
        server.exchange(req_without_len(65_537)).unwrap(),
        "len=65537",
    );
    assert_ends_with(
        server.exchange(req_without_len(70_000)).unwrap(),
        "len=70000",
    );
    assert_eq!(
        server.exchange(req_without_len(70_001)).unwrap(),
        "HTTP/1.1 413 Payload Too Large\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 25\r\n\r\nUploaded data is too big.",
    );
}

#[test]
fn body_not_pending() {
    let server = TestServer::start(|_req| Response::get_body_and_reprocess(100)).unwrap();
    assert_eq!(
        server
            .exchange("M / HTTP/1.1\r\ncontent-length:3\r\n\r\nabc")
            .unwrap(),
        "HTTP/1.1 500 Internal Server Error\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 21\r\n\r\nInternal server error",
    );
}

#[test]
fn already_got_body() {
    let server = TestServer::start(|_req| Response::get_body_and_reprocess(70_000)).unwrap();
    assert_eq!(
        server.exchange(req_with_len(66_000)).unwrap(),
        "HTTP/1.1 500 Internal Server Error\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 21\r\n\r\nInternal server error",
    );
}

#[test]
fn get_body_then_drop() {
    let server = TestServer::start(|req| {
        if req.body.is_pending() {
            Response::get_body_and_reprocess(70_000)
        } else {
            Response::drop_connection()
        }
    })
    .unwrap();
    assert_eq!(server.exchange(req_with_len(66_000)).unwrap(), "",);
}

#[test]
fn error_writing_body_file() {
    let mut server = TestServer::start(|req| {
        assert!(req.body.is_pending());
        Response::get_body_and_reprocess(70_000)
    })
    .unwrap();
    server.cache_dir.take();
    std::thread::sleep(Duration::from_millis(100));
    assert_eq!(
        server.exchange(req_with_len(66_000)).unwrap(),
        "HTTP/1.1 500 Internal Server Error\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 21\r\n\r\nInternal server error",
    );
}

#[test]
fn error_reading_body_file() {
    let mut server = TestServer::start(|req| {
        if req.body.is_pending() {
            Response::get_body_and_reprocess(70_000)
        } else {
            std::thread::sleep(Duration::from_millis(200));
            req.body.reader().unwrap();
            unreachable!();
        }
    })
    .unwrap();
    let mut tcp_stream = server.connect_and_send(req_with_len(66_000)).unwrap();
    std::thread::sleep(Duration::from_millis(100));
    server.cache_dir.take();
    assert_eq!(
        read_to_string(&mut tcp_stream).unwrap(),
        "HTTP/1.1 500 Internal Server Error\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 12\r\n\r\nServer error",
    );
}

#[test]
fn fast_reply() {
    let server = TestServer::start(|_req| Response::new(200)).unwrap();
    let before = Instant::now();
    let reply = server.exchange("M / HTTP/1.1\r\n\r\n").unwrap();
    check_elapsed(before, 0..100).unwrap();
    assert_eq!(reply, "HTTP/1.1 200 OK\r\ncontent-length: 0\r\n\r\n",);
}

#[test]
fn slow_reply() {
    let server = TestServer::start(|_req| {
        std::thread::sleep(Duration::from_millis(100));
        Response::new(200)
    })
    .unwrap();
    let before = Instant::now();
    let reply = server.exchange("M / HTTP/1.1\r\n\r\n").unwrap();
    check_elapsed(before, 100..200).unwrap();
    assert_eq!(reply, "HTTP/1.1 200 OK\r\ncontent-length: 0\r\n\r\n",);
}

#[test]
fn expect_100_continue() {
    let server = TestServer::start(|req| {
        if req.body.is_pending() {
            std::thread::sleep(Duration::from_millis(100));
            Response::get_body_and_reprocess(70_000)
        } else {
            let len = req.body.reader().unwrap().bytes().count();
            Response::text(200, format!("len={len}"))
        }
    })
    .unwrap();
    // Small body
    let mut tcp_stream = server.connect().unwrap();
    let before = Instant::now();
    tcp_stream
        .write_all(b"M / HTTP/1.1\r\ncontent-length:100\r\nexpect: 100-continue\r\n\r\n")
        .unwrap();
    assert_eq!(
        read_for(&mut tcp_stream, 100).unwrap(),
        "HTTP/1.1 100 Continue\r\ncontent-length: 0\r\n\r\n"
    );
    check_elapsed(before, 100..200).unwrap();
    tcp_stream.write_all(&[b'a'; 100]).unwrap();
    assert_ends_with(read_for(&mut tcp_stream, 100).unwrap(), "len=100");
    // Large body
    let mut tcp_stream = server.connect().unwrap();
    let before = Instant::now();
    tcp_stream
        .write_all(b"M / HTTP/1.1\r\ncontent-length:66000\r\nexpect: 100-continue\r\n\r\n")
        .unwrap();
    assert_eq!(
        read_response(&mut tcp_stream).unwrap(),
        "HTTP/1.1 100 Continue\r\ncontent-length: 0\r\n\r\n"
    );
    check_elapsed(before, 100..200).unwrap();
    tcp_stream.write_all(&[b'a'; 66_000]).unwrap();
    assert_ends_with(read_response(&mut tcp_stream).unwrap(), "len=66000");
}

#[test]
fn client_incomplete_read() {
    let server = TestServer::start(|_req| {
        Response::text(
            200,
            std::iter::repeat(b'a').take(1_000_000).collect::<Vec<u8>>(),
        )
    })
    .unwrap();
    let mut tcp_stream = server.connect_and_send("M / HTTP/1.1\r\n\r\n").unwrap();
    // read_to_string(&mut tcp_stream).unwrap();
    tcp_stream.read_exact(&mut [0_u8; 10]).unwrap();
    drop(tcp_stream);
    std::thread::sleep(Duration::from_millis(100));
}

#[test]
fn unsupported_transfer_encoding() {
    let server = TestServer::start(|_req| Response::new(200)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\ntransfer-encoding: unknown1\r\n\r\n").unwrap(),
        "HTTP/1.1 400 Bad Request\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 38\r\n\r\nHttpError::UnsupportedTransferEncoding",
    );
}

#[test]
fn chunked_not_supported() {
    let server = TestServer::start(|_req| Response::get_body_and_reprocess(100)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\ntransfer-encoding:chunked\r\n\r\n3\r\nabc\r\n0\r\n\r\n").unwrap(),
        "HTTP/1.1 400 Bad Request\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 38\r\n\r\nHttpError::UnsupportedTransferEncoding",
    );
}

#[test]
fn chunked_not_last() {
    let server = TestServer::start(|_req| Response::get_body_and_reprocess(100)).unwrap();
    assert_eq!(
        server.exchange("M / HTTP/1.1\r\ntransfer-encoding:chunked, gzip\r\n\r\n3\r\nabc\r\n0\r\n\r\n").unwrap(),
        "HTTP/1.1 400 Bad Request\r\ncontent-type: text/plain; charset=UTF-8\r\ncontent-length: 38\r\n\r\nHttpError::UnsupportedTransferEncoding",
    );
}

#[test]
fn content_length_zero() {
    let server = TestServer::start(|_req| Response::new(200)).unwrap();
    assert_eq!(
        server
            .exchange("M / HTTP/1.1\r\ncontent-length:0\r\n\r\n")
            .unwrap(),
        "HTTP/1.1 200 OK\r\ncontent-length: 0\r\n\r\n"
    );
}