fuel-core-poa 0.17.11

use crate::ports::Database;
use anyhow::ensure;
use fuel_core_chain_config::ConsensusConfig;
use fuel_core_types::{
    blockchain::{
        block::Block,
        consensus::poa::PoAConsensus,
        header::BlockHeader,
    },
    fuel_tx::Input,
};

#[cfg(test)]
mod tests;

/// The config of the block verifier.
pub struct Config {
    /// If the manual block is enabled, skip verification of some fields.
    pub enabled_manual_blocks: bool,
}

// TODO: Make this function `async` and await the synchronization with the relayer.
pub fn verify_consensus(
    consensus_config: &ConsensusConfig,
    header: &BlockHeader,
    consensus: &PoAConsensus,
) -> bool {
    match consensus_config {
        ConsensusConfig::PoA { signing_key } => {
            let id = header.id();
            let m = id.as_message();
            consensus
                .signature
                .recover(m)
                .map_or(false, |k| Input::owner(&k) == *signing_key)
        }
    }
}

pub fn verify_block_fields<D: Database>(
    config: &Config,
    database: &D,
    block: &Block,
) -> anyhow::Result<()> {
    let height = *block.header().height();
    ensure!(
        height != 0u32.into(),
        "The PoA block can't have the zero height"
    );

    let prev_height = height - 1u32.into();
    let prev_root = database.block_header_merkle_root(&prev_height)?;
    let header = block.header();
    ensure!(
        header.prev_root() == &prev_root,
        "Previous root of the next block should match the previous block root"
    );

    let prev_header = database.block_header(&prev_height)?;

    ensure!(
        header.da_height >= prev_header.da_height,
        "The `da_height` of the next block can't be lower"
    );

    // Skip the verification of the time if it is possible to produce blocks manually.
    if !config.enabled_manual_blocks {
        ensure!(
            header.time() >= prev_header.time(),
            "The `time` of the next block can't be lower"
        );
    }

    ensure!(
        header.consensus.application_hash == header.application.hash(),
        "The application hash mismatch."
    );

    // TODO: We can check the root of the transactions and the root of the messages here.
    //  But we do the same in the executor right now during validation mode. I will not check
    //  it for now. But after merge of the https://github.com/FuelLabs/fuel-core/pull/889 it
    //  is should be easy to do with the `validate_transactions` method. And maybe we want
    //  to remove this check from the executor and replace it with check that transaction
    //  id is not modified during the execution.

    Ok(())
}