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mod msb;
mod node;
mod path_iterator;
mod position;
mod position_path;
mod storage_map;
mod subtree;

pub use msb::Msb;
pub use node::{Node, ParentNode};
pub use path_iterator::AsPathIterator;
pub use position::Position;
pub use storage_map::StorageMap;
pub use subtree::Subtree;

pub(crate) use position_path::PositionPath;

pub const NODE: u8 = 0x01;
pub const LEAF: u8 = 0x00;

pub type Bytes1 = [u8; 1];
pub type Bytes2 = [u8; 2];
pub type Bytes4 = [u8; 4];
pub type Bytes8 = [u8; 8];
pub type Bytes16 = [u8; 16];
pub type Bytes32 = [u8; 32];

use alloc::vec::Vec;
pub type ProofSet = Vec<Bytes32>;

// Merkle Tree hash of an empty list
// MTH({}) = Hash()
pub const fn empty_sum_sha256() -> &'static Bytes32 {
    const EMPTY_SUM: Bytes32 = [
        0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14, 0x9a, 0xfb, 0xf4, 0xc8, 0x99, 0x6f, 0xb9,
        0x24, 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b, 0x93, 0x4c, 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52,
        0xb8, 0x55,
    ];

    &EMPTY_SUM
}

#[test]
fn empty_sum_sha256_is_empty_hash() {
    use digest::Digest;
    use sha2::Sha256;

    let sum = empty_sum_sha256();
    let empty = Bytes32::from(Sha256::new().finalize());

    assert_eq!(&empty, sum);
}