/*
 * Copyright ConsenSys AG.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
package org.hyperledger.besu.ethereum.api.jsonrpc.internal.privacy.methods.eea;

import static org.apache.logging.log4j.LogManager.getLogger;
import static org.hyperledger.besu.ethereum.api.jsonrpc.JsonRpcEnclaveErrorConverter.convertEnclaveInvalidReason;
import static org.hyperledger.besu.ethereum.api.jsonrpc.JsonRpcErrorConverter.convertTransactionInvalidReason;
import static org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcError.DECODE_ERROR;
import static org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcError.PRIVATE_FROM_DOES_NOT_MATCH_ENCLAVE_PUBLIC_KEY;
import static org.hyperledger.besu.ethereum.privacy.PrivacyGroupUtil.findOffchainPrivacyGroup;

import org.hyperledger.besu.enclave.types.PrivacyGroup;
import org.hyperledger.besu.ethereum.api.jsonrpc.RpcMethod;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.JsonRpcRequestContext;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.methods.JsonRpcMethod;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.privacy.methods.EnclavePublicKeyProvider;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcError;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcErrorResponse;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcResponse;
import org.hyperledger.besu.ethereum.api.jsonrpc.internal.response.JsonRpcSuccessResponse;
import org.hyperledger.besu.ethereum.core.Address;
import org.hyperledger.besu.ethereum.core.Transaction;
import org.hyperledger.besu.ethereum.eth.transactions.TransactionPool;
import org.hyperledger.besu.ethereum.mainnet.ValidationResult;
import org.hyperledger.besu.ethereum.privacy.PrivacyController;
import org.hyperledger.besu.ethereum.privacy.PrivateTransaction;
import org.hyperledger.besu.ethereum.rlp.RLP;
import org.hyperledger.besu.ethereum.rlp.RLPException;
import org.hyperledger.besu.ethereum.transaction.TransactionInvalidReason;

import java.util.Optional;

import org.apache.logging.log4j.Logger;
import org.apache.tuweni.bytes.Bytes;

public class EeaSendRawTransaction implements JsonRpcMethod {

  private static final Logger LOG = getLogger();
  final TransactionPool transactionPool;
  final PrivacyController privacyController;
  private final EnclavePublicKeyProvider enclavePublicKeyProvider;

  public EeaSendRawTransaction(
      final TransactionPool transactionPool,
      final PrivacyController privacyController,
      final EnclavePublicKeyProvider enclavePublicKeyProvider) {
    this.transactionPool = transactionPool;
    this.privacyController = privacyController;
    this.enclavePublicKeyProvider = enclavePublicKeyProvider;
  }

  @Override
  public String getName() {
    return RpcMethod.EEA_SEND_RAW_TRANSACTION.getMethodName();
  }

  @Override
  public JsonRpcResponse response(final JsonRpcRequestContext requestContext) {
    final Object id = requestContext.getRequest().getId();
    final String rawPrivateTransaction = requestContext.getRequiredParameter(0, String.class);

    try {
      final PrivateTransaction privateTransaction =
          PrivateTransaction.readFrom(RLP.input(Bytes.fromHexString(rawPrivateTransaction)));

      final String enclavePublicKey =
          enclavePublicKeyProvider.getEnclaveKey(requestContext.getUser());

      if (!privateTransaction.getPrivateFrom().equals(Bytes.fromBase64String(enclavePublicKey))) {
        return new JsonRpcErrorResponse(id, PRIVATE_FROM_DOES_NOT_MATCH_ENCLAVE_PUBLIC_KEY);
      }

      final Optional<Bytes> maybePrivacyGroupId = privateTransaction.getPrivacyGroupId();

      final Optional<PrivacyGroup> maybePrivacyGroup =
          findPrivacyGroup(
              privacyController, maybePrivacyGroupId, enclavePublicKey, privateTransaction);

      final ValidationResult<TransactionInvalidReason> validationResult =
          privacyController.validatePrivateTransaction(privateTransaction, enclavePublicKey);

      if (!validationResult.isValid()) {
        return new JsonRpcErrorResponse(
            id, convertTransactionInvalidReason(validationResult.getInvalidReason()));
      }

      final JsonRpcResponse ret =
          createPMTAndAddToTxPool(
              id,
              privateTransaction,
              maybePrivacyGroup,
              maybePrivacyGroupId,
              enclavePublicKey,
              Address.DEFAULT_PRIVACY);
      return ret;

    } catch (final JsonRpcErrorResponseException e) {
      return new JsonRpcErrorResponse(id, e.getJsonRpcError());
    } catch (final IllegalArgumentException | RLPException e) {
      LOG.error(e);
      return new JsonRpcErrorResponse(id, DECODE_ERROR);
    } catch (final Exception e) {
      return new JsonRpcErrorResponse(id, convertEnclaveInvalidReason(e.getMessage()));
    }
  }

  Optional<PrivacyGroup> findPrivacyGroup(
      final PrivacyController privacyController,
      final Optional<Bytes> maybePrivacyGroupId,
      final String enclavePublicKey,
      final PrivateTransaction privateTransaction) {
    final Optional<PrivacyGroup> maybePrivacyGroup =
        findOffchainPrivacyGroup(privacyController, maybePrivacyGroupId, enclavePublicKey);
    return maybePrivacyGroup;
  }

  JsonRpcResponse createPMTAndAddToTxPool(
      final Object id,
      final PrivateTransaction privateTransaction,
      final Optional<PrivacyGroup> maybePrivacyGroup,
      final Optional<Bytes> maybePrivacyGroupId,
      final String enclavePublicKey,
      final Address privacyPrecompileAddress) {
    final String privateTransactionLookupId =
        privacyController.sendTransaction(privateTransaction, enclavePublicKey, maybePrivacyGroup);
    final Transaction privacyMarkerTransaction =
        privacyController.createPrivacyMarkerTransaction(
            privateTransactionLookupId, privateTransaction, privacyPrecompileAddress);
    return transactionPool
        .addLocalTransaction(privacyMarkerTransaction)
        .either(
            () -> new JsonRpcSuccessResponse(id, privacyMarkerTransaction.getHash().toString()),
            errorReason -> getJsonRpcErrorResponse(id, errorReason));
  }

  JsonRpcErrorResponse getJsonRpcErrorResponse(
      final Object id, final TransactionInvalidReason errorReason) {
    if (errorReason.equals(TransactionInvalidReason.INTRINSIC_GAS_EXCEEDS_GAS_LIMIT)) {
      return new JsonRpcErrorResponse(id, JsonRpcError.PMT_FAILED_INTRINSIC_GAS_EXCEEDS_LIMIT);
    }
    return new JsonRpcErrorResponse(id, convertTransactionInvalidReason(errorReason));
  }
}
