// Copyright 2019. The Tari Project
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use tari_transaction_components::tari_proof_of_work::{Difficulty, PowAlgorithm};
/// Immutable struct that is guaranteed to have achieved the target difficulty
#[derive(Debug, Clone, Copy)]
pub struct AchievedTargetDifficulty {
    pow_algo: PowAlgorithm,
    achieved: Difficulty,
    target: Difficulty,
}

impl AchievedTargetDifficulty {
    /// Checks if the achieved difficulty is higher than the target difficulty. If not, None is returned because a valid
    /// AchievedTargetDifficulty cannot be constructed.
    pub fn try_construct(pow_algo: PowAlgorithm, target: Difficulty, achieved: Difficulty) -> Option<Self> {
        if achieved < target {
            return None;
        }
        Some(Self {
            pow_algo,
            achieved,
            target,
        })
    }

    /// Returns the achieved difficulty
    pub fn achieved(&self) -> Difficulty {
        self.achieved
    }

    /// Returns the target difficulty
    pub fn target(&self) -> Difficulty {
        self.target
    }

    /// Returns the PoW algorithm
    pub fn pow_algo(&self) -> PowAlgorithm {
        self.pow_algo
    }
}
