1  // Copyright (c) 2019-2025 Alpha-Delta Network Inc.
 2  // This file is part of the alphavm library.
 3  
 4  // Licensed under the Apache License, Version 2.0 (the "License");
 5  // you may not use this file except in compliance with the License.
 6  // You may obtain a copy of the License at:
 7  
 8  // http://www.apache.org/licenses/LICENSE-2.0
 9  
10  // Unless required by applicable law or agreed to in writing, software
11  // distributed under the License is distributed on an "AS IS" BASIS,
12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  // See the License for the specific language governing permissions and
14  // limitations under the License.
15  
16  use super::*;
17  
18  impl<N: Network> FromBytes for Metadata<N> {
19      /// Reads the metadata from the buffer.
20      #[inline]
21      fn read_le<R: Read>(mut reader: R) -> IoResult<Self> {
22          // Read the version.
23          let version = u8::read_le(&mut reader)?;
24          // Ensure the version is valid.
25          if version != 1 {
26              return Err(error("Invalid metadata version"));
27          }
28  
29          // Read from the buffer.
30          let network = u16::read_le(&mut reader)?;
31          let round = u64::read_le(&mut reader)?;
32          let height = u32::read_le(&mut reader)?;
33          let cumulative_weight = u128::read_le(&mut reader)?;
34          let cumulative_proof_target = u128::read_le(&mut reader)?;
35          let coinbase_target = u64::read_le(&mut reader)?;
36          let proof_target = u64::read_le(&mut reader)?;
37          let last_coinbase_target = u64::read_le(&mut reader)?;
38          let last_coinbase_timestamp = i64::read_le(&mut reader)?;
39          let timestamp = i64::read_le(&mut reader)?;
40  
41          // Construct the metadata.
42          Self::new(
43              network,
44              round,
45              height,
46              cumulative_weight,
47              cumulative_proof_target,
48              coinbase_target,
49              proof_target,
50              last_coinbase_target,
51              last_coinbase_timestamp,
52              timestamp,
53          )
54          .map_err(into_io_error)
55      }
56  }
57  
58  impl<N: Network> ToBytes for Metadata<N> {
59      /// Writes the metadata to the buffer.
60      #[inline]
61      fn write_le<W: Write>(&self, mut writer: W) -> IoResult<()> {
62          // Write the version.
63          1u8.write_le(&mut writer)?;
64  
65          // Write to the buffer.
66          self.network.write_le(&mut writer)?;
67          self.round.write_le(&mut writer)?;
68          self.height.write_le(&mut writer)?;
69          self.cumulative_weight.write_le(&mut writer)?;
70          self.cumulative_proof_target.write_le(&mut writer)?;
71          self.coinbase_target.write_le(&mut writer)?;
72          self.proof_target.write_le(&mut writer)?;
73          self.last_coinbase_target.write_le(&mut writer)?;
74          self.last_coinbase_timestamp.write_le(&mut writer)?;
75          self.timestamp.write_le(&mut writer)
76      }
77  }
78  
79  #[cfg(test)]
80  mod tests {
81      use super::*;
82      use console::network::MainnetV0;
83  
84      type CurrentNetwork = MainnetV0;
85  
86      #[test]
87      fn test_bytes() -> Result<()> {
88          let rng = &mut TestRng::default();
89  
90          for expected in [crate::header::metadata::test_helpers::sample_block_metadata(rng)].into_iter() {
91              // Check the byte representation.
92              let expected_bytes = expected.to_bytes_le()?;
93              assert_eq!(expected, Metadata::read_le(&expected_bytes[..])?);
94              assert!(Metadata::<CurrentNetwork>::read_le(&expected_bytes[1..]).is_err());
95          }
96          Ok(())
97      }
98  }