//! A simple echo server that listens on 127.0.0.1:8089

use std::{error::Error, io::Write, net::TcpListener};

use uhttp::Lift;

fn main() -> Result<(), Box<dyn Error>> {
	let listener = TcpListener::bind("127.0.0.1:8089")?;
	loop {
		let (mut stream, _) = listener.accept()?;
		let mut conn = uhttp::Connection::new(uhttp::Role::Server);

		let mut body: Vec<u8> = Vec::new();
		let mut buf = vec![0; 1024].into_boxed_slice();
		let mut buf = uhttp_ext::Buf::new(&mut buf);

		let mut method_not_allowed = false;

		loop {
			let data = buf.filled();
			let (remaining, r) = conn.handle_recv(data).lift();
			match r.map_err(|e| e.kind) {
				Err(uhttp::ErrorKind::NeedMoreData) => {
					buf.read_from(&mut stream)?;
					continue;
				},
				Err(e) => panic!("{e:?}"),
				Ok(event) => {
					match event {
						uhttp::Event::RequestLine(r) => {
							if !r.method.eq_ignore_ascii_case("post") {
								method_not_allowed = true;
							}
						},
						uhttp::Event::RecvDone => break,
						uhttp::Event::BodyChunk(b) => body.extend_from_slice(b),
						_ => (),
					};
				},
			};

			let len = data.len() - remaining.len();
			buf.pop_front(len);
		}

		let parts: &[uhttp::Event] = if method_not_allowed {
			&[
				uhttp::Event::StatusLine(uhttp::StatusLine {
					version: uhttp::Version::HTTP1_1,
					status_code: 405,
					status_text: "Method not allowed",
				}),
				uhttp::Event::HeadersEnd,
				uhttp::Event::SendDone,
			]
		} else {
			&[
				uhttp::Event::StatusLine(uhttp::StatusLine {
					version: uhttp::Version::HTTP1_1,
					status_code: 200,
					status_text: "OK",
				}),
				uhttp::Event::Header(uhttp::Header::Special(
					uhttp::HeaderSpecial::ContentLength(body.len()),
				)),
				uhttp::Event::HeadersEnd,
				uhttp::Event::BodyChunk(body.as_slice()),
				uhttp::Event::SendDone,
			]
		};

		let buf = vec![0; 1024];
		let mut cursor = uhttp::WriteCursor::new(buf);
		for p in parts {
			if let Err(e) = conn.handle_send(p, &mut cursor) {
				panic!("{e:?}")
			};
			stream.write_all(cursor.written())?;
			cursor.reset();
		}
	}
}