//offer ota and config mode

use embedded_svc::http::Method;
use esp_idf_svc::http::server::EspHttpServer;
use esp_ota::OtaUpdate;

#[allow(unused_variables)]
pub fn httpd(initial_config:bool) -> EspHttpServer<'static> {

    let mut server = EspHttpServer::new(&Default::default()).unwrap();

    server
        .fn_handler("/",Method::Get, move |request| {
            let mut response = request.into_ok_response()?;
            match initial_config {
                true => response.write(include_bytes!("initial_config.html"))?,
                false => response.write(include_bytes!("config.html"))?
            };
            return Ok(())
        }).unwrap();
    server
        .fn_handler("/version",Method::Get,  |request| {
            let mut response = request.into_ok_response()?;
            response.write(env!("VERGEN_GIT_DESCRIBE").as_bytes())?;
            return Ok(())
        }).unwrap();
    server
        .fn_handler("/ota.js",Method::Get, |request| {
            let mut response = request.into_ok_response()?;
            response.write(include_bytes!("ota.js"))?;
            return Ok(())
        }).unwrap();
    server
        .fn_handler("/ota", Method::Post,  |mut request| {
            let ota = OtaUpdate::begin();
            if ota.is_err(){
                let error_text = ota.unwrap_err().to_string();
                request.into_status_response(500)?.write(error_text.as_bytes())?;
                return Ok(());
            }
            let mut ota = ota.unwrap();
            println!("start ota");
            
            //having a larger buffer is not really faster, requires more stack and prevents the progress bar from working ;)
            const BUFFER_SIZE:usize = 512;
            let mut buffer :[u8;BUFFER_SIZE] = [0;BUFFER_SIZE];
            let mut total_read: usize = 0;
            loop {
                let read = request.read(&mut buffer).unwrap();
                total_read += read;
                println!("received {read} bytes ota {total_read}");
                let to_write =  & buffer[0 .. read];

                
                let write_result = ota.write(to_write);
                if write_result.is_err(){
                    let error_text = write_result.unwrap_err().to_string();
                    request.into_status_response(500)?.write(error_text.as_bytes())?;
                    return Ok(());
                }
                println!("wrote {read} bytes ota {total_read}");
                if read == 0 {
                    break;
                }
            }
            println!("finish ota");
            let partition = ota.raw_partition();
            println!("finalizing and changing boot partition to {partition:?}");

            let finalizer = ota.finalize();
            if finalizer.is_err(){
                let error_text = finalizer.err().unwrap().to_string();
                request.into_status_response(500)?.write(error_text.as_bytes())?;
                return Ok(());
            }
            let mut finalizer = finalizer.unwrap();
            
            println!("changing boot partition");
            finalizer.set_as_boot_partition().unwrap();
            finalizer.restart();

        
            //return Ok(())
        }).unwrap();
    return server;
}