sdmmc-core 0.5.0

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

lib_bitfield! {
    /// Argumentument for CMD23.
    pub Argument(u32): u16 {
        /// Indicates whether the reliable writer feature is enable for a read/write block command.
        raw_reliable_write_request: 31;
        /// Indicates whether the command is part of a packed command.
        pub packed: 30;
        /// Indicates if the request is tagged, mutually exclusive to `Context ID`.
        raw_tag_request: 29;
        /// Represents the `Context ID` of the request, mutually exclusive to `TAG_REQUEST`.
        raw_context_id: 28, 25;
        /// Indicates whether forced programming is enabled, and the write cache is bypassed.
        raw_forced_programming: 24;
        /// Specifies the block count for read/write block commands.
        pub block_count: 15, 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)
    }

    /// Converts a [`u32`] into an [`Argument`].
    pub const fn from_bits(val: u32) -> Self {
        Self(val)
    }

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

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

    /// Indicates whether the reliable writer feature is enable for a read/write block command.
    ///
    /// # Note
    ///
    /// Only relevant for non-packed commands.
    pub const fn reliable_write_request(&self) -> bool {
        !self.packed() && self.raw_reliable_write_request()
    }

    /// Indicates if the request is tagged, mutually exclusive to `Context ID`.
    ///
    /// # Note
    ///
    /// Only relevant for non-packed commands.
    pub const fn tag_request(&self) -> bool {
        !self.packed() && self.raw_tag_request()
    }

    pub fn set_tag_request(&mut self, val: bool) {
        if val {
            self.set_packed(false);
            self.set_context_id(0);
        }

        self.set_raw_tag_request(val);
    }

    /// Gets the `Context ID` of the request, mutually exclusive to `TAG_REQUEST`.
    ///
    /// # Note
    ///
    /// Only relevant for non-packed commands.
    pub const fn context_id(&self) -> u8 {
        match self.packed() {
            false if !self.tag_request() => self.raw_context_id() as u8,
            _ => 0,
        }
    }

    /// Sets the `Context ID` of the request, mutually exclusive to `TAG_REQUEST`.
    ///
    /// # Note
    ///
    /// Only relevant for non-packed commands.
    pub fn set_context_id(&mut self, id: u8) {
        if id != 0 {
            self.set_packed(false);
            self.set_tag_request(false);
        }

        self.set_raw_context_id(id as u32);
    }

    /// 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 From<u32> for Argument {
    fn from(val: u32) -> Self {
        Self::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() {
        (1..=u32::BITS)
            .map(|r| ((1u64 << r) - 1) as u32)
            .for_each(|raw_arg| {
                let exp_block_count = (raw_arg & 0xffff) as u16;
                let raw = raw_arg.to_be_bytes();
                let mut exp_arg = Argument(raw_arg);

                assert_eq!(Argument::from_bits(raw_arg), exp_arg);
                assert_eq!(Argument::from(raw_arg), exp_arg);

                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), Ok(exp_arg));
                assert_eq!(Argument::try_from(raw), Ok(exp_arg));

                assert_eq!(exp_arg.block_count(), exp_block_count);

                exp_arg.set_block_count(0);
                assert_eq!(exp_arg.block_count(), 0);

                exp_arg.set_block_count(exp_block_count as u32);
                assert_eq!(exp_arg.block_count(), exp_block_count);

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