// Copyright 2025 Don MacAskill. Licensed under MIT or Apache-2.0.

//! This module provides CRC-32 support.

pub mod algorithm;

pub mod consts;

pub(crate) mod width32_ops;

#[cfg(all(

    feature = "std",

    any(target_arch = "x86", target_arch = "x86_64", target_arch = "aarch64")

))]

pub(crate) mod fusion;

#[cfg(test)]

mod property_tests {

    use crate::test::miri_compatible_proptest_config;

    use crate::{checksum, CrcAlgorithm};

    use proptest::prelude::*;

    proptest! {

        #![proptest_config(miri_compatible_proptest_config())]

        /// Feature: crc16-hardware-acceleration, Property 4: CRC-32 and CRC-64 backwards compatibility

        /// *For any* existing CRC-32 or CRC-64 configuration and any input byte sequence, the

        /// computed checksum SHALL match the result from the `crc` crate reference implementation,

        /// ensuring no regression from CRC-16 changes.

        /// **Validates: Requirements 3.1, 3.2, 3.4**

        #[test]

        fn prop_crc32_compatibility(data in proptest::collection::vec(any::<u8>(), 0..1024)) {

            use crate::test::consts::{RUST_CRC32_ISCSI, RUST_CRC32_ISO_HDLC, RUST_CRC32_BZIP2, RUST_CRC32_MPEG_2};

            // Test CRC-32/ISCSI (reflected)

            let our_iscsi = checksum(CrcAlgorithm::Crc32Iscsi, &data);

            let ref_iscsi = RUST_CRC32_ISCSI.checksum(&data) as u64;

            prop_assert_eq!(

                our_iscsi, ref_iscsi,

                "CRC-32/ISCSI mismatch for {} bytes: our=0x{:08X}, ref=0x{:08X}",

                data.len(), our_iscsi, ref_iscsi

            );

            // Test CRC-32/ISO-HDLC (reflected)

            let our_hdlc = checksum(CrcAlgorithm::Crc32IsoHdlc, &data);

            let ref_hdlc = RUST_CRC32_ISO_HDLC.checksum(&data) as u64;

            prop_assert_eq!(

                our_hdlc, ref_hdlc,

                "CRC-32/ISO-HDLC mismatch for {} bytes: our=0x{:08X}, ref=0x{:08X}",

                data.len(), our_hdlc, ref_hdlc

            );

            // Test CRC-32/BZIP2 (forward/non-reflected)

            let our_bzip2 = checksum(CrcAlgorithm::Crc32Bzip2, &data);

            let ref_bzip2 = RUST_CRC32_BZIP2.checksum(&data) as u64;

            prop_assert_eq!(

                our_bzip2, ref_bzip2,

                "CRC-32/BZIP2 mismatch for {} bytes: our=0x{:08X}, ref=0x{:08X}",

                data.len(), our_bzip2, ref_bzip2

            );

            // Test CRC-32/MPEG-2 (forward/non-reflected)

            let our_mpeg2 = checksum(CrcAlgorithm::Crc32Mpeg2, &data);

            let ref_mpeg2 = RUST_CRC32_MPEG_2.checksum(&data) as u64;

            prop_assert_eq!(

                our_mpeg2, ref_mpeg2,

                "CRC-32/MPEG-2 mismatch for {} bytes: our=0x{:08X}, ref=0x{:08X}",

                data.len(), our_mpeg2, ref_mpeg2

            );

        }

    }

}