/*

* 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.

*/

package org.lance;

import org.lance.operation.Operation;

import com.google.common.base.MoreObjects;

import org.apache.arrow.util.Preconditions;

import java.util.HashMap;

import java.util.Map;

import java.util.Objects;

import java.util.Optional;

import java.util.UUID;

/**

* Align with the Transaction struct in rust. The transaction won't commit the status to original

* dataset. It will return a new dataset after committed.

*/

public class Transaction {

private final long readVersion;

private final String uuid;

private final Map<String, String> writeParams;

private final Optional<Map<String, String>> transactionProperties;

// Mainly for JNI usage

private final Dataset dataset;

private final Operation operation;

private Transaction(

Dataset dataset,

long readVersion,

String uuid,

Operation operation,

Map<String, String> writeParams,

Map<String, String> transactionProperties) {

this.dataset = dataset;

this.readVersion = readVersion;

this.uuid = uuid;

this.operation = operation;

this.writeParams = writeParams != null ? writeParams : new HashMap<>();

this.transactionProperties = Optional.ofNullable(transactionProperties);

}

public long readVersion() {

return readVersion;

}

public String uuid() {

return uuid;

}

public Operation operation() {

return operation;

}

public Map<String, String> writeParams() {

return writeParams;

}

public Optional<Map<String, String>> transactionProperties() {

return transactionProperties;

}

public Dataset commit() {

if (dataset == null) {

throw new UnsupportedOperationException("Transaction doesn't support create new dataset yet");

}

return dataset.commitTransaction(this);

}

public void release() {

operation.release();

}

@Override

public String toString() {

return MoreObjects.toStringHelper(this)

.add("readVersion", readVersion)

.add("uuid", uuid)

.add("operation", operation)

.add("writeParams", writeParams)

.add("transactionProperties", transactionProperties)

.toString();

}

@Override

public boolean equals(Object o) {

if (this == o) {

return true;

}

if (o == null || getClass() != o.getClass()) {

return false;

}

Transaction that = (Transaction) o;

return readVersion == that.readVersion

&& uuid.equals(that.uuid)

&& Objects.equals(operation, that.operation)

&& Objects.equals(writeParams, that.writeParams)

&& Objects.equals(transactionProperties, that.transactionProperties);

}

public static class Builder {

private final String uuid;

private final Dataset dataset;

private long readVersion;

private Operation operation;

private Map<String, String> writeParams;

private Map<String, String> transactionProperties;

public Builder(Dataset dataset) {

this.dataset = dataset;

this.uuid = UUID.randomUUID().toString();

}

public Builder readVersion(long readVersion) {

this.readVersion = readVersion;

return this;

}

public Builder transactionProperties(Map<String, String> properties) {

this.transactionProperties = properties;

return this;

}

public Builder writeParams(Map<String, String> writeParams) {

this.writeParams = writeParams;

return this;

}

public Builder operation(Operation operation) {

validateState();

this.operation = operation;

return this;

}

private void validateState() {

if (operation != null) {

throw new IllegalStateException(

String.format("Operation %s has been set", operation.name()));

}

}

public Transaction build() {

Preconditions.checkState(operation != null, "TransactionBuilder has no operations");

return new Transaction(

dataset, readVersion, uuid, operation, writeParams, transactionProperties);

}

}

}