package org.cache2k;

/*
 * #%L
 * cache2k API only package
 * %%
 * Copyright (C) 2000 - 2016 headissue GmbH, Munich
 * %%
 * 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.
 * #L%
 */

import org.cache2k.spi.Cache2kCoreProvider;
import org.cache2k.spi.SingleProviderResolver;

import java.util.Collection;
import java.util.concurrent.TimeUnit;

/**
 * @author Jens Wilke; created: 2013-06-25
 */
public abstract class CacheBuilder<K,T>
  extends RootAnyBuilder<K, T> implements Cloneable {

  private static CacheBuilder PROTOTYPE;

  static {
    try {
      Cache2kCoreProvider _provider =
        SingleProviderResolver.getInstance().resolve(Cache2kCoreProvider.class);
      PROTOTYPE = _provider.getBuilderImplementation().newInstance();
    } catch (Exception ex) {
      throw new Error("cache2k-core module missing, no builder prototype", ex);
    }
  }

  @SuppressWarnings("unchecked")
  public static <K,T> CacheBuilder<K,T> newCache(Class<K> _keyType, Class<T> _valueType) {
    CacheBuilder<K,T> cb = null;
    try {
      cb = (CacheBuilder<K,T>) PROTOTYPE.clone();
    } catch (CloneNotSupportedException ignored) {  }
    cb.ctor(_keyType, _valueType, null);
    return cb;
  }

  @SuppressWarnings("unchecked")
  public static <K, C extends Collection<T>, T> CacheBuilder<K, C> newCache(
    Class<K> _keyType, Class<C> _collectionType, Class<T> _entryType) {
    CacheBuilder<K,C> cb = null;
    try {
      cb = (CacheBuilder<K,C>) PROTOTYPE.clone();
    } catch (CloneNotSupportedException ignored) { }
    cb.ctor(_keyType, _collectionType, _entryType);
    return cb;
  }

  protected EntryExpiryCalculator entryExpiryCalculator;
  protected CacheSource cacheSource;
  protected CacheSourceWithMetaInfo cacheSourceWithMetaInfo;
  protected RefreshController refreshController;
  protected ExperimentalBulkCacheSource experimentalBulkCacheSource;
  protected BulkCacheSource bulkCacheSource;
  protected ExceptionExpiryCalculator exceptionExpiryCalculator;

  /** Builder is constructed from prototype */
  protected void ctor(Class<K> _keyType, Class<T> _valueType, Class<?> _entryType) {
    root = this;
    config = new CacheConfig();
    config.setValueType(_valueType);
    config.setKeyType(_keyType);
    config.setEntryType(_entryType);
  }

  /**
   * Constructs a cache name out of the simple class name and fieldname.
   *
   * a cache name should be unique within an application / cache manager!
   */
  public CacheBuilder<K, T> name(Class<?> _class, String _fieldName) {
    config.setName(_class.getSimpleName() + "." + _fieldName);
    return this;
  }

  public CacheBuilder<K, T> name(Class<?> _class) {
    config.setName(_class.getSimpleName());
    return this;
  }

  /**
   * Constructs a cache name out of the simple class name and fieldname.
   *
   * a cache name should be unique within an application / cache manager!
   */
  public CacheBuilder<K, T> name(Object _containingObject, String _fieldName) {
    return name(_containingObject.getClass(), _fieldName);
  }

  public CacheBuilder<K, T> name(String v) {
    config.setName(v);
    return this;
  }

  public CacheBuilder<K, T> keepDataAfterExpired(boolean v) {
    config.setKeepDataAfterExpired(v);
    return this;
  }

  public CacheBuilder<K, T> maxSize(int v) {
    config.setMaxSize(v);
    return this;
  }

  public CacheBuilder<K, T> maxSizeBound(int v) {
    config.setMaxSizeHighBound(v);
    return this;
  }

  /**
   * Keep entries forever. Default is false. By default the cache uses an expiry time
   * of 10 minutes.
   */
  public CacheBuilder<K, T> eternal(boolean v) {
    config.setEternal(v);
    return this;
  }

  /**
   * If an exceptions gets thrown by the cache source, suppress it if there is
   * a previous value. When this is active, and an exception was suppressed
   * the expiry is determined by the exception expiry settings. Default: true
   */
  public CacheBuilder<K, T> suppressExceptions(boolean v) {
    config.setSuppressExceptions(v);
    return this;
  }

  public CacheBuilder<K, T> heapEntryCapacity(int v) {
    config.setHeapEntryCapacity(v);
    return this;
  }

  /**
   * Set the time duration after an entry expires. To switch off time
   * based expiry use {@link #eternal(boolean)}. A value of 0 effectively
   * disables the cache.
   *
   * <p/>If an {@link org.cache2k.EntryExpiryCalculator} is set, this setting
   * controls the maximum possible expiry duration.
   */
  public CacheBuilder<K, T> expiryDuration(long v, TimeUnit u) {
    config.setExpiryMillis(u.toMillis(v));
    return this;
  }

  /**
   * Separate timeout in the case an exception was thrown in the cache source.
   * By default 10% of the normal expiry is used.
   */
  public CacheBuilder<K, T> exceptionExpiryDuration(long v, TimeUnit u) {
    config.setExceptionExpiryMillis(u.toMillis(v));
    return this;
  }

  /**
   * @deprecated since 0.20, please use {@link #expiryDuration}
   */
  public CacheBuilder<K, T> expirySecs(int v) {
    config.setExpiryMillis(v * 1000);
    return this;
  }

  /**
   * @deprecated since 0.20, please use {@link #expiryDuration}
   */
  public CacheBuilder<K, T> expiryMillis(long v) {
    config.setExpiryMillis(v);
    return this;
  }

  public CacheBuilder<K, T> source(CacheSource<K, T> g) {
    cacheSource = g;
    return this;
  }

  public CacheBuilder<K, T> source(CacheSourceWithMetaInfo<K, T> g) {
    cacheSourceWithMetaInfo = g;
    return this;
  }

  public CacheBuilder<K, T> source(ExperimentalBulkCacheSource<K, T> g) {
    experimentalBulkCacheSource = g;
    return this;
  }

  public CacheBuilder<K, T> source(BulkCacheSource<K, T> g) {
    bulkCacheSource = g;
    return this;
  }

  /**
   * Set expiry calculator to use. If {@link #expiryDuration(long, java.util.concurrent.TimeUnit)}
   * is set to 0 then expiry calculation is not used, all entries expire immediately.
   */
  public CacheBuilder<K, T> entryExpiryCalculator(EntryExpiryCalculator c) {
    entryExpiryCalculator = c;
    return this;
  }

  /**
   * Set expiry calculator to use in case of an exception happened in the {@link CacheSource}.
   */
  public CacheBuilder<K, T> exceptionExpiryCalculator(ExceptionExpiryCalculator c) {
    exceptionExpiryCalculator = c;
    return this;
  }

  /**
   * @deprecated since 0.20, please use {@link #entryExpiryCalculator}
   */
  public CacheBuilder<K, T> refreshController(RefreshController c) {
    refreshController = c;
    return this;
  }

  public CacheBuilder<K, T> implementation(Class<?> c) {
    config.setImplementation(c);
    return this;
  }

  @Deprecated
  public CacheConfig getConfig() {
    return null;
  }


  /**
   * Builds a cache with the specified configuration parameters.
   * The builder reused to build caches with similar or identical
   * configuration. The builder is not thread safe.
   */
  public abstract Cache<K, T> build();

}