use embedded_hal::{
	blocking::spi::Transfer,
	digital::v2::OutputPin,
};
use core::marker::PhantomData;

use crate::cpld::{DoOnGetRefMutData, SelectChip, IssueIOUpdate};
use crate::Error;

pub struct SPISlave<'a, DEV: 'a, SPI, CS0, CS1, CS2, GPIO> (
	&'a DEV,
	u8,			// Channel of SPI slave
	bool,		// Need I/O Update
	PhantomData<(SPI, CS0, CS1, CS2, GPIO)>,
);

pub struct Parts<'a, DEV: 'a, SPI, CS0, CS1, CS2, GPIO> {
	pub spi1: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi2: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi3: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi4: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi5: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi6: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
	pub spi7: SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>,
}

impl<'a, DEV, SPI, CS0, CS1, CS2, GPIO> Parts<'a, DEV, SPI, CS0, CS1, CS2, GPIO> {
	pub(crate) fn new(cpld: &'a DEV) -> Self {
		Parts {
			spi1: SPISlave(&cpld, 1, false, PhantomData),
			spi2: SPISlave(&cpld, 2, false, PhantomData),
			spi3: SPISlave(&cpld, 3, true, PhantomData),
			spi4: SPISlave(&cpld, 4, true, PhantomData),
			spi5: SPISlave(&cpld, 5, true, PhantomData),
			spi6: SPISlave(&cpld, 6, true, PhantomData),
			spi7: SPISlave(&cpld, 7, true, PhantomData),
		}
	}
}

impl<'a, DEV, SPI, CS0, CS1, CS2, GPIO, E> Transfer<u8> for SPISlave<'a, DEV, SPI, CS0, CS1, CS2, GPIO>
where
	CS2: OutputPin,
	CS1: OutputPin,
	CS0: OutputPin,
	DEV: DoOnGetRefMutData<SPI, CS0, CS1, CS2, GPIO>,
	SPI: Transfer<u8, Error = E>,
	GPIO: OutputPin,
{
	type Error = Error<E>;

	fn transfer<'w>(&mut self, words: &'w mut[u8]) -> Result<&'w [u8], Self::Error> {
		self.0.do_on_get_ref_mut_data(move |mut dev| {
			dev.select_chip(self.1);
			let result = dev.spi.transfer(words).map_err(Error::SPI);
			dev.select_chip(0);
			if self.2 {
				dev.issue_io_update();
			}
			result
		})	
	}
}