use crate::fat_error::FatError;
use crate::webserver::read_up_to_bytes_from_request;
use crate::BOARD_ACCESS;
use edge_http::io::server::Connection;
use edge_http::Method;
use embedded_io_async::{Read, Write};
use log::info;

pub(crate) async fn ota_operations<T, const N: usize>(
    conn: &mut Connection<'_, T, { N }>,
    method: Method,
) -> Result<Option<u32>, FatError>
where
    T: Read + Write,
{
    Ok(match method {
        Method::Options => {
            conn.initiate_response(
                200,
                Some("OK"),
                &[
                    ("Access-Control-Allow-Origin", "*"),
                    ("Access-Control-Allow-Headers", "*"),
                    ("Access-Control-Allow-Methods", "*"),
                ],
            )
            .await?;
            Some(200)
        }
        Method::Post => {
            let mut offset = 0_usize;
            let mut chunk = 0;
            loop {
                let buf = read_up_to_bytes_from_request(conn, Some(4096)).await?;
                if buf.len() == 0 {
                    info!("file request for  ota finished");
                    let mut board = BOARD_ACCESS.get().await.lock().await;
                    board.board_hal.get_esp().finalize_ota().await?;
                    break;
                } else {
                    let mut board = BOARD_ACCESS.get().await.lock().await;
                    board.board_hal.progress(chunk as u32).await;
                    // Erase next block if we are at a 4K boundary (including the first block at offset 0)
                    info!("erasing and writing block 0x{offset:x}");
                    board
                        .board_hal
                        .get_esp()
                        .write_ota(offset as u32, &*buf)
                        .await?;
                }
                offset = offset + buf.len();
                chunk = chunk + 1;
            }
            BOARD_ACCESS
                .get()
                .await
                .lock()
                .await
                .board_hal
                .clear_progress()
                .await;
            conn.initiate_response(
                200,
                Some("OK"),
                &[
                    ("Access-Control-Allow-Origin", "*"),
                    ("Access-Control-Allow-Headers", "*"),
                    ("Access-Control-Allow-Methods", "*"),
                ],
            )
            .await?;
            Some(200)
        }
        _ => None,
    })
}