use starknet::ContractAddress;
use core::array::{Array, ArrayTrait};

/// Validator information structure
#[derive(Drop, Serde, starknet::Store)]
struct ValidatorInfo {
    address: ContractAddress,
    public_key: felt252,
    voting_power: u64,
}

/// Mock contract that returns validators at a given height
#[starknet::contract]
mod ConsensusValidators {
    use super::*;

    #[storage]
    struct Storage {}

    // Ed25519 public keys generated for testing (felt252-compatible)
    const VALIDATOR_1: ValidatorInfo = ValidatorInfo {
        address: 0x111.try_into().unwrap(),
        public_key: 0x3b2223a9c54386b0b4f0f6b58fc2ec1e3b7f21581397ee3c7f,
        voting_power: 1000,
    };
    const VALIDATOR_2: ValidatorInfo = ValidatorInfo {
        address: 0x222.try_into().unwrap(),
        public_key: 0xd7db502088c25c78f0dd01492f86878da27b8fd391b001ed,
        voting_power: 1500,
    };
    const VALIDATOR_3: ValidatorInfo = ValidatorInfo {
        address: 0x333.try_into().unwrap(),
        public_key: 0x43cbc327a0b331fd17e915196ac339321ffd3bcaa7308f49d2,
        voting_power: 2000,
    };
    const VALIDATOR_4: ValidatorInfo = ValidatorInfo {
        address: 0x444.try_into().unwrap(),
        public_key: 0x8474f2adcef8935233876183dce7bb9a9136f53c57e578a85c,
        voting_power: 1200,
    };

    /// Builds the rotated list for a given height.
    fn rotate(height: u64) -> Array<ValidatorInfo> {
        let mut out = ArrayTrait::new();

        let n: u64 = 4_u64;
        let start: u64 = height % n;

        let mut i: u64 = 0_u64;
        while i < n {
            let idx = (start + i) % n;
            match idx {
                0_u64 => out.append(VALIDATOR_1),
                1_u64 => out.append(VALIDATOR_2),
                2_u64 => out.append(VALIDATOR_3),
                _     => out.append(VALIDATOR_4),
            };
            i += 1_u64;
        }

        out
    }

    /// Returns validator addresses at a given height
    #[external(v0)]
    fn get_validators_at_height(self: @ContractState, height: u64) -> Array<ContractAddress> {
        let validators = rotate(height);
        let mut addresses = ArrayTrait::new();
        let span = validators.span();
        let mut i = 0;
        while i < span.len() {
            addresses.append(*span.at(i).address);
            i += 1;
        }
        addresses
    }

    /// Returns detailed validator information at a given height.
    #[external(v0)]
    fn get_validator_info_at_height(self: @ContractState, height: u64) -> Array<ValidatorInfo> {
        rotate(height)
    }
}