rtvm-primitives 3.1.1

use super::{
    trusted_setup_points::{G1_POINTS, G2_POINTS},
    KzgSettings,
};
use core::hash::{Hash, Hasher};
use once_cell::race::OnceBox;
use std::{boxed::Box, sync::Arc};

/// KZG Settings that allow us to specify a custom trusted setup.
/// or use hardcoded default settings.
#[derive(Debug, Clone, Default, Eq)]
pub enum EnvKzgSettings {
    /// Default mainnet trusted setup
    #[default]
    Default,
    /// Custom trusted setup.
    Custom(Arc<c_kzg::KzgSettings>),
}

// Implement PartialEq and Hash manually because `c_kzg::KzgSettings` does not implement them
impl PartialEq for EnvKzgSettings {
    fn eq(&self, other: &Self) -> bool {
        match (self, other) {
            (Self::Default, Self::Default) => true,
            (Self::Custom(a), Self::Custom(b)) => Arc::ptr_eq(a, b),
            _ => false,
        }
    }
}

impl Hash for EnvKzgSettings {
    fn hash<H: Hasher>(&self, state: &mut H) {
        core::mem::discriminant(self).hash(state);
        match self {
            Self::Default => {}
            Self::Custom(settings) => Arc::as_ptr(settings).hash(state),
        }
    }
}

impl EnvKzgSettings {
    /// Return set KZG settings.
    ///
    /// In will initialize the default settings if it is not already loaded.
    pub fn get(&self) -> &KzgSettings {
        match self {
            Self::Default => {
                static DEFAULT: OnceBox<KzgSettings> = OnceBox::new();
                DEFAULT.get_or_init(|| {
                    let settings =
                        KzgSettings::load_trusted_setup(G1_POINTS.as_ref(), G2_POINTS.as_ref())
                            .expect("failed to load default trusted setup");
                    Box::new(settings)
                })
            }
            Self::Custom(settings) => settings,
        }
    }
}