sdmmc-core 0.5.0

use crate::lib_bitfield;
use crate::result::{Error, Result};

mod rw;

pub use rw::*;

lib_bitfield! {
    /// Argumentument for CMD52.
    pub Argument(u32): u32 {
        raw_rw: 31;
        raw_fno: 30, 27;
        raw_addr: 25, 9;
        raw_data: 7, 0;
    }
}

impl Argument {
    /// Represents the byte length of the [Argument].
    pub const LEN: usize = 4;
    /// Represents the default value of the [Argument].
    pub const DEFAULT: u32 = 0;

    /// Creates a new [Argument].
    pub const fn new() -> Self {
        Self(Self::DEFAULT)
    }

    /// Gets the `rw` field of the [Argument].
    pub const fn rw(&self) -> ReadWrite {
        ReadWrite::from_bool(self.raw_rw())
    }

    /// Sets the `rw` field of the [Argument].
    ///
    /// # Note
    ///
    /// If mode is set to [Read](ReadWrite::Read), sets the `data` field to zero.
    pub fn set_rw(&mut self, val: ReadWrite) {
        self.set_raw_rw(val.into_bool());
        if matches!(val, ReadWrite::Read) {
            self.set_raw_data(0);
        }
    }

    /// Gets the `fno` field of the [Argument].
    pub const fn fno(&self) -> u8 {
        self.raw_fno() as u8
    }

    /// Sets the `fno` field of the [Argument].
    pub fn set_fno(&mut self, val: u8) {
        self.set_raw_fno(val as u32);
    }

    /// Gets the `addr` field for the [Argument].
    pub const fn addr(&self) -> u32 {
        self.raw_addr()
    }

    /// Sets the `addr` field for the [Argument].
    pub fn set_addr(&mut self, val: u32) {
        self.set_raw_addr(val);
    }

    /// Gets the `data` field of the [Argument].
    ///
    /// # Note
    ///
    /// Only relevant when the `rw` field is set to [Write](ReadWrite::Write).
    pub const fn data(&self) -> u8 {
        match self.rw() {
            ReadWrite::Read => 0,
            ReadWrite::Write => self.raw_data() as u8,
        }
    }

    /// Sets the `data` field of the [Argument].
    ///
    /// # Note
    ///
    /// Also sets the `rw` field to [Write](ReadWrite::Write).
    pub fn set_data(&mut self, val: u8) {
        self.set_raw_data(val as u32);
        self.set_rw(ReadWrite::Write);
    }

    /// Attempts to convert a [`u32`] into an [`Argument`].
    pub const fn try_from_bits(val: u32) -> Result<Self> {
        Ok(Self(val))
    }

    /// Converts the [Argument] into a byte array.
    pub const fn bytes(&self) -> [u8; Self::LEN] {
        self.0.to_be_bytes()
    }

    /// Attempts to convert a byte slice into an [`Argument`].
    pub const fn try_from_bytes(val: &[u8]) -> Result<Self> {
        match val.len() {
            len if len < Self::LEN => Err(Error::invalid_length(len, Self::LEN)),
            _ => Self::try_from_bits(u32::from_be_bytes([val[0], val[1], val[2], val[3]])),
        }
    }
}

impl Default for Argument {
    fn default() -> Self {
        Self::new()
    }
}

impl From<Argument> for u32 {
    fn from(val: Argument) -> Self {
        val.bits()
    }
}

impl From<Argument> for [u8; Argument::LEN] {
    fn from(val: Argument) -> Self {
        val.bytes()
    }
}

impl TryFrom<u32> for Argument {
    type Error = Error;

    fn try_from(val: u32) -> Result<Self> {
        Self::try_from_bits(val)
    }
}

impl TryFrom<&[u8]> for Argument {
    type Error = Error;

    fn try_from(val: &[u8]) -> Result<Self> {
        Self::try_from_bytes(val)
    }
}

impl<const N: usize> TryFrom<&[u8; N]> for Argument {
    type Error = Error;

    fn try_from(val: &[u8; N]) -> Result<Self> {
        Self::try_from_bytes(val.as_ref())
    }
}

impl<const N: usize> TryFrom<[u8; N]> for Argument {
    type Error = Error;

    fn try_from(val: [u8; N]) -> Result<Self> {
        Self::try_from_bytes(val.as_ref())
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_fields() {
        let new_rw = ReadWrite::new();

        (1..=u32::BITS)
            .map(|r| ((1u64 << r) - 1) as u32)
            .for_each(|raw_arg| {
                let mut exp_arg = Argument(raw_arg);
                let raw = raw_arg.to_be_bytes();

                let exp_rw = ReadWrite::from_bool((raw_arg & (1 << 31)) != 0);
                let exp_fno = ((raw_arg & 0x7800_0000) >> 27) as u8;
                let exp_addr = (raw_arg & 0x3fffe00) >> 9;
                let exp_data = (raw_arg & 0xff) as u8;

                assert_eq!(Argument::try_from_bits(raw_arg), Ok(exp_arg));
                assert_eq!(Argument::try_from_bytes(&raw), Ok(exp_arg));
                assert_eq!(Argument::try_from(raw_arg), Ok(exp_arg));
                assert_eq!(Argument::try_from(&raw), Ok(exp_arg));
                assert_eq!(Argument::try_from(raw), Ok(exp_arg));

                assert_eq!(exp_arg.bits(), raw_arg);
                assert_eq!(exp_arg.bytes(), raw);
                assert_eq!(exp_arg.addr(), exp_addr);

                assert_eq!(exp_arg.rw(), exp_rw);
                assert_eq!(exp_arg.fno(), exp_fno);
                assert_eq!(exp_arg.addr(), exp_addr);
                if matches!(exp_rw, ReadWrite::Write) {
                    assert_eq!(exp_arg.data(), exp_data);
                }

                exp_arg.set_rw(new_rw);
                assert_eq!(exp_arg.rw(), new_rw);
                assert_eq!(exp_arg.data(), 0);

                exp_arg.set_rw(exp_rw);
                assert_eq!(exp_arg.rw(), exp_rw);

                exp_arg.set_fno(0);
                assert_eq!(exp_arg.fno(), 0);

                exp_arg.set_fno(exp_fno);
                assert_eq!(exp_arg.fno(), exp_fno);

                exp_arg.set_addr(0);
                assert_eq!(exp_arg.addr(), 0);

                exp_arg.set_addr(exp_addr);
                assert_eq!(exp_arg.addr(), exp_addr);

                exp_arg.set_data(0);
                assert_eq!(exp_arg.data(), 0);

                exp_arg.set_data(exp_data);
                assert_eq!(exp_arg.data(), exp_data);
                assert_eq!(exp_arg.rw(), ReadWrite::Write);
            });
    }
}