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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "bls12377.sol"; // Hypothetical library for BLS12-377
import "kzg.sol";       // Hypothetical library for KZG Commitments
import "plonk.sol";     // Hypothetical library for PLONK

contract ShieldContract {
    // Trusted setup parameters for KZG Commitments
    KZG.SetupParameters kzgSetup;
    // Trusted setup parameters for PLONK
    PLONK.SetupParameters plonkSetup;

constructor(KZG.SetupParameters memory _kzgSetup, PLONK.SetupParameters memory _plonkSetup) {
        kzgSetup = _kzgSetup;
        plonkSetup = _plonkSetup;
    }

// This function allows a user to submit a proof without revealing their transaction details.
    function submitProof(
        KZG.Commitment memory commitment,
        PLONK.Proof memory proof,
        uint256 publicInput
    )
        public
    {
        // Verify the commitment using KZG
        require(KZG.verify(kzgSetup, commitment), "KZG Commitment verification failed");

// Verify the zero knowledge proof using PLONK
        require(PLONK.verify(plonkSetup, proof, publicInput), "PLONK proof verification failed");

// If both verifications pass, execute the transaction (details hidden)
        executeShieldedTransaction(commitment, proof, publicInput);
    }

function executeShieldedTransaction(
    KZG.Commitment memory commitment,
    PLONK.Proof memory proof,
    uint256 publicInput
)
    internal
{
    // Decode hidden data from the proof or commitment
    // This is extremely simplified; in reality decoding might be more involved
    address sender = decodeSender(commitment, proof);
    address recipient = decodeRecipient(commitment, proof);
    uint256 amount = decodeAmount(commitment, proof);

// Check additional conditions (e.g., sufficient balance)
    require(tokenBalance[sender] >= amount, "Insufficient balance");

// Update state securely based on hidden data
    tokenBalance[sender] -= amount;
    tokenBalance[recipient] += amount;

// Optionally emit an event for the transaction
    emit ShieldedTransfer(sender, recipient, amount);
}

}