import "cat20Proto.scrypt";import "../utils/stateUtils.scrypt";import "../utils/backtrace.scrypt";import "../utils/sigHashUtils.scrypt";import "guardProto.scrypt";import "../utils/txProof.scrypt";

struct TokenUnlockArgs {
  bool isUserSpend;
  bytes userPubKeyPrefix;
  PubKey userPubKey;
  Sig userSig;
  int contractInputIndex;
}

struct GuardInfo {
  XrayedTxIdPreimg3 tx;
  int inputIndexVal;
  bytes outputIndex;
  GuardConstState guardState;
}

contract CAT20 {
  bytes minterScript;
  bytes guardScript;
  public function unlock(TokenUnlockArgs tokenUnlockArgs, CAT20State preState, PreTxStatesInfo preTxStatesInfo, GuardInfo guardInfo, BacktraceInfo backtraceInfo, SHPreimage shPreimage, PrevoutsCtx prevoutsCtx, bytes[6] spentScriptsCtx) {
    require(checkSig(SigHashUtils.checkSHPreimage(shPreimage), SigHashUtils.Gx));
    SigHashUtils.checkPrevoutsCtx(prevoutsCtx, shPreimage.hashPrevouts, shPreimage.inputIndex);
    SigHashUtils.checkSpentScriptsCtx(spentScriptsCtx, shPreimage.hashSpentScripts);
    StateUtils.verifyPreStateHash(preTxStatesInfo, CAT20Proto.stateHash(preState), backtraceInfo.preTx.outputScriptList[0], prevoutsCtx.outputIndexVal);
    bytes preScript = spentScriptsCtx[(prevoutsCtx.inputIndexVal)];
    Backtrace.verifyToken(prevoutsCtx.spentTxhash, backtraceInfo, this.minterScript, preScript);
    this.valitateGuard(guardInfo, preScript, preState, prevoutsCtx.inputIndexVal, prevoutsCtx.prevouts, spentScriptsCtx);
    if(tokenUnlockArgs.isUserSpend) {
        require(hash160(tokenUnlockArgs.userPubKeyPrefix + tokenUnlockArgs.userPubKey) == preState.ownerAddr);
        require(checkSig(tokenUnlockArgs.userSig, tokenUnlockArgs.userPubKey));
      } else {
        require(preState.ownerAddr == hash160(spentScriptsCtx[(tokenUnlockArgs.contractInputIndex)]));
      }
    require(true);
  }
  function valitateGuard(GuardInfo guardInfo, bytes preScript, CAT20State preState, int inputIndexVal, bytes[6] prevouts, bytes[6] spentScriptsCtx) : bool {
    bytes guardHashRoot = GuardProto.stateHash(guardInfo.guardState);
    require(guardInfo.guardState.tokenScript == preScript);
    require(StateUtils.getStateScript(guardHashRoot, 1) == guardInfo.tx.outputScriptList[0]);
    require(preState.amount > 0);
    require(guardInfo.guardState.inputTokenAmountArray[(inputIndexVal)] == preState.amount);
    bytes guardTxid = TxProof.getTxIdFromPreimg3(guardInfo.tx);
    require(prevouts[(guardInfo.inputIndexVal)] == guardTxid + guardInfo.outputIndex);
    require(spentScriptsCtx[(guardInfo.inputIndexVal)] == this.guardScript);
    return true;
  }
}