@ieigen/zkzru/src/circuitInput.js

An implementation of [ZK-ZKRollup](https://github.com/ieigen/ZKZRU) in which the relayer **does not** publish transaction data to the main chain, but only publishes the new Merkle root at every update. This provides gas savings but not data availability g

const buildMimc7 = require("circomlibjs").buildMimc7;

module.exports = async function getCircuitInput(stateTransition) {
  let mimcjs = await buildMimc7()
  let F = mimcjs.F
  const currentState = stateTransition.originalState;
  const txTree = stateTransition.txTree;

  const depth = txTree.depth;

  const paths2txRoot = stateTransition.paths2txRoot
  const paths2txRootPos = stateTransition.paths2txRootPos
  const deltas = stateTransition.deltas

  const intermediateRoots = new Array(2 ** (depth + 1) + 1);
  const paths2rootFrom = new Array(2 ** depth);
  const paths2rootFromPos = new Array(2 ** depth);
  const paths2rootTo = new Array(2 ** depth);
  const paths2rootToPos = new Array(2 ** depth);
  const balanceFrom = new Array(2 ** depth);
  const balanceTo = new Array(2 ** depth);
  const nonceTo = new Array(2 ** depth);
  const tokenTypeTo = new Array(2 ** depth);

  intermediateRoots[0] = F.toString(currentState);

  let delta;

  for (let i = 0; i < deltas.length; i++) {
    delta = deltas[i];

    intermediateRoots[2 * i + 1] = F.toString(delta.rootFromNewSender);

    paths2rootFrom[i] = delta.senderProof.map((item) => F.toString(item)),
    paths2rootFromPos[i] = delta.senderProofPos,

    paths2rootTo[i] = delta.receiverProof.map((item) => F.toString(item)),
    paths2rootToPos[i] = delta.receiverProofPos,

    intermediateRoots[2 * i + 2] = F.toString(delta.rootFromNewReceiver);

    balanceFrom[i] = delta.balanceFrom.toString();

    balanceTo[i] = delta.balanceTo.toString();
    nonceTo[i] = delta.nonceTo;
    tokenTypeTo[i] = delta.tokenTypeTo;
  }

  const txs = txTree.txs;
  const fromX = new Array(2 ** depth);
  const fromY = new Array(2 ** depth);
  const fromIndex = new Array(2 ** depth);
  const toX = new Array(2 ** depth);
  const toY = new Array(2 ** depth);
  const nonceFrom = new Array(2 ** depth);
  const amount = new Array(2 ** depth);
  const tokenTypeFrom = new Array(2 ** depth);
  const R8x = new Array(2 ** depth);
  const R8y = new Array(2 ** depth);
  const S = new Array(2 ** depth);

  for (let i = 0; i < txs.length; i++) {
    const tx = txs[i];

    fromX[i] = F.toString(tx.fromX);
    fromY[i] = F.toString(tx.fromY);
    fromIndex[i] = tx.fromIndex;
    // NOTE: zero address will be not zero
    toX[i] = tx.toX == 0 ? 0 : F.toString(tx.toX);
    toY[i] = tx.toY == 0 ? 0 : F.toString(tx.toY);
    nonceFrom[i] = tx.nonce;
    amount[i] = tx.amount.toString();
    tokenTypeFrom[i] = tx.tokenType;

    R8x[i] = F.toString(tx.R8x);
    R8y[i] = F.toString(tx.R8y);
    S[i] = tx.S.toString();
    tx.checkSignature()
  }

  return {
    txRoot: F.toString(txTree.root),
    paths2txRoot: (paths2txRoot),
    paths2txRootPos: paths2txRootPos,
    currentState: F.toString(currentState),
    intermediateRoots: (intermediateRoots),
    paths2rootFrom: (paths2rootFrom),
    paths2rootFromPos: paths2rootFromPos,
    paths2rootTo: (paths2rootTo),
    paths2rootToPos: paths2rootToPos,
    fromX: (fromX),
    fromY: (fromY),
    fromIndex: fromIndex,
    toX: (toX),
    toY: (toY),
    nonceFrom: nonceFrom,
    amount: amount,
    tokenTypeFrom: tokenTypeFrom,
    R8x: (R8x),
    R8y: (R8y),
    S: (S),
    balanceFrom: balanceFrom,
    balanceTo: balanceTo,
    nonceTo: nonceTo,
    tokenTypeTo: tokenTypeTo
  }
}