1use constants;
 2use utils;
 3
 4pub struct TreeNode {
 5    pub child_l: [u8; 32],
 6    pub child_r: [u8; 32],
 7}
 8
 9impl TreeNode {
10    pub fn bytes(&self) -> Vec<u8> {
11        concatenate_arrays(&self.child_l, &self.child_r)
12    }
13    pub fn ht(&self) -> [u8; 32] {
14        utils::hash_vec(self.bytes())
15    }
16}
17
18fn concatenate_arrays<T: Clone>(x: &[T], y: &[T]) -> Vec<T> {
19    let mut concat = x.to_vec();
20    concat.extend_from_slice(y);
21
22    concat
23}
24
25pub fn parse_node_bytes(b: Vec<u8>) -> TreeNode {
26    if b == constants::EMPTYNODEVALUE {
27        let n = TreeNode {
28            child_l: constants::EMPTYNODEVALUE,
29            child_r: constants::EMPTYNODEVALUE,
30        };
31        return n;
32    }
33    let child_l = &b[0..32];
34    let child_r = &b[32..];
35    TreeNode {
36        child_l: *array_ref!(child_l, 0, 32),
37        child_r: *array_ref!(child_r, 0, 32),
38    }
39}
40
41#[cfg(test)]
42mod tests {
43    use super::*;
44    use rustc_hex::ToHex;
45
46    #[test]
47    fn test_hash_vec() {
48        let n = TreeNode {
49            child_l: constants::EMPTYNODEVALUE,
50            child_r: constants::EMPTYNODEVALUE,
51        };
52        assert_eq!(
53            "ad3228b676f7d3cd4284a5443f17f1962b36e491b30a40b2405849e597ba5fb5",
54            n.ht().to_hex()
55        )
56    }
57}