use std::fs;
use std::io::prelude::*;
use std::net::TcpListener;
use std::net::TcpStream;

use async_std::task;
use std::time::Duration;

// TODO: must be set in a conf file
const SERVER_URL: &str = "127.0.0.1:9000";

// switch to an asynchronous main function
#[async_std::main]
async fn main() {
    let listener = TcpListener::bind(SERVER_URL).unwrap();
    println!("server is listening at {}", SERVER_URL);
    for stream in listener.incoming() {
        let stream = stream.unwrap();
        handle_connection(stream).await;
    }
}

// TODO: must properly handle the request
async fn handle_connection(mut stream: TcpStream) {
    let mut buffer = [0; 1024];
    stream.read(&mut buffer).unwrap();

    let get = b"GET / HTTP/1.1\r\n";

    // TODO: request musy be parsed correctly
    let status_line = if buffer.starts_with(get) {
        "HTTP/1.1 200 OK\r\n"
    } else {
        "HTTP/1.1 404 NOT FOUND\r\n"
    };

    let content_type = "Content-Type: application/json\r\n\r\n";
    let json = r#"{"access_token":"AAAAAAAAAAAA.BBBBBBBBBB.CCCCCCCCCC","refresh_token": "DDDDDDDDDDD.EEEEEEEEEEE.FFFFF"}"#;
    let response = format!("{status_line}{content_type}{json}\n");

    println!("return status code : {}", status_line);
    stream.write(response.as_bytes()).unwrap();
    stream.flush().unwrap();
}