use tokio::net::TcpListener;
use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader, BufWriter};
use tokio::sync::mpsc::Sender;

use crate::state::ControlCommand;

pub async fn tcp_command_server(app_control_tx: Sender<ControlCommand>) {
    let listener = TcpListener::bind("127.0.0.1:12345").await.unwrap();
    println!("TCP command server listening on 12345");

    loop {
        let (socket, addr) = listener.accept().await.unwrap();
        app_control_tx.try_send(ControlCommand::TcpConnected(true)).unwrap();
        println!("Client connected: {:?}", addr);

        let tx = app_control_tx.clone();

        tokio::spawn(async move {
            let (reader, writer) = socket.into_split();

            let reader = BufReader::new(reader);
            let mut writer = BufWriter::new(writer);
            let mut lines = reader.lines();

            while let Ok(Some(line)) = lines.next_line().await {
                println!("Received: {}", line);

                match parse_command(&line) {
                    Some(signal) => {
                        if tx.send(signal).await.is_ok() {
                            let _ = writer.write_all(b"OK\n").await;
                        } else {
                            let _ = writer.write_all(b"ERR internal channel failure\n").await;
                            break;
                        }
                    }
                    None => {
                        let _ = writer.write_all(b"ERR unknown command\n").await;
                    }
                }

                let _ = writer.flush().await;
            }

            println!("Client disconnected: {:?}", addr);
            tx.try_send(ControlCommand::TcpConnected(false)).unwrap();
        });
    }
}

fn parse_command(line: &str) -> Option<ControlCommand> {
    let parts: Vec<&str> = line.split_whitespace().collect();

    match parts.as_slice() {
        // ["SET_FREQ", freq_str] => {
        //     if let Ok(freq) = freq_str.parse::<f32>() {
        //         Some(ControlCommand::SetFrequency(freq))
        //     } else {
        //         None
        //     }
        // }
        // ["SET_LEAD_MODE", mode_str] => {
        //     match mode_str.to_uppercase().as_str() {
        //         "LEAD_OFF" => Some(ControlCommand::ChangeLeadMode(crate::state::LeadMode::LeadOff)),
        //         "LEAD_I" => Some(ControlCommand::ChangeLeadMode(crate::state::LeadMode::LeadI)),
        //         "LEAD_II" => Some(ControlCommand::ChangeLeadMode(crate::state::LeadMode::LeadII)),
        //         "LEAD_III" => Some(ControlCommand::ChangeLeadMode(crate::state::LeadMode::LeadIII)),
        //         _ => None,
        //     }
        // }
        // ["SET_DFT_NUM", dft_num_str] => {
        //     if let Ok(dft_num) = dft_num_str.parse::<u32>() {
        //         Some(ControlCommand::ChangeDftNum(IcdDftNum(dft_num)))
        //     } else {
        //         None
        //     }
        // }
        // ["SET_SWEEP_POINTS", sweep_points_str] => {
        //     if let Ok(sweep_points) = sweep_points_str.parse::<u32>() {
        //         Some(ControlCommand::ChangeSweepPoints(SweepPoints(sweep_points)))
        //     } else {
        //         None
        //     }
        // }
        // ["SET_ELECTRODE_CONFIG", config_str] => {
        //     // Example: "SET_ELECTRODE_CONFIG 1,0,1,0,1,0,1,0"
        //     let config_parts: Vec<&str> = config_str.split(',').collect();
        //     if config_parts.len() == 8 {
        //         let mut config = [false; 8];
        //         for (i, part) in config_parts.iter().enumerate() {
        //             if let Ok(val) = part.parse::<u8>() {
        //                 config[i] = val != 0;
        //             } else {
        //                 return None;
        //             }
        //         }
        //         Some(ControlCommand::ChangeElectrodeSettings(crate::state::ElectrodeSettings(config)))
        //     } else {
        //         None
        //     }
        // }
        ["START", mode_str] => {
            match mode_str.to_uppercase().as_str() {
                "SINGLE" => {
                    Some(ControlCommand::Start(crate::state::Mode::Single))
                },
                "SWEEP" => {
                    Some(ControlCommand::Start(crate::state::Mode::Sweep))
                },
                _ => None,
            }
        }
        ["STOP"] => Some(ControlCommand::Stop),

        _ => {
            eprintln!("Unknown command: {}", line);
            None
        }
    }
}