use crate::config::DefaultSection;
use crate::tile::TileData;
use futures::channel::mpsc::Receiver;
use futures::StreamExt;
use tokio::io::{self, AsyncWriteExt};

pub async fn launch<E>(
    num_tiles: usize,
    mut receiver: Receiver<Result<TileData, E>>,
    _default: DefaultSection,
) -> io::Result<!>
where
    E: Send + std::fmt::Debug,
{
    let mut stdout = io::stdout();
    stdout.write_all(b"{ \"version\": 1 }\n[").await?;

    let mut blocks = Vec::new();
    blocks.resize_with(num_tiles, Default::default);
    loop {
        match receiver.next().await.unwrap() {
            Ok(message) => {
                if message.sender_id < num_tiles {
                    blocks[message.sender_id] = Some(message.block);
                } else {
                    eprintln!("Invalid message with sender id {}", message.sender_id);
                    continue;
                }
                let mut serialized = serde_json::to_vec(&blocks).unwrap();
                serialized.extend_from_slice(b",\n");
                stdout.write_all(&serialized).await?;
            }
            Err(err) => {
                eprintln!("Error in tile: {:?}", err);
            }
        }
    }
}