Copyright (c), Data Geekery GmbH, contact@datageekery.com
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.
/**
 * Copyright (c), Data Geekery GmbH, contact@datageekery.com
 *
 * 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.jooq.lambda;

import java.util.*;
import java.util.function.BooleanSupplier;
import java.util.function.Supplier;

import org.jooq.lambda.tuple.Tuple2;

Author:
Lukas Eder/**
 * @author Lukas Eder
 */
class Partition<T> {

    final List<Tuple2<T, Long>> list;
    final Map<Object, Object>   cache;

    Partition(Collection<Tuple2<T, Long>> list) {
        this.list = list instanceof ArrayList ? (List<Tuple2<T, Long>>) list : new ArrayList<>(list);
        this.cache = new HashMap<>();
    }

    <R> R cacheIf(boolean condition, Object key, Supplier<? extends R> value) {
        return cacheIf(() -> condition, () -> key, value);
    }

    <R> R cacheIf(boolean condition, Supplier<?> key, Supplier<? extends R> value) {
        if (condition)
            return cache(key, value);
        else
            return value.get();
    }

    <R> R cacheIf(BooleanSupplier condition, Object key, Supplier<? extends R> value) {
        return cacheIf(condition, () -> key, value);
    }

    <R> R cacheIf(BooleanSupplier condition, Supplier<?> key, Supplier<? extends R> value) {
        if (condition.getAsBoolean())
            return cache(key, value);
        else
            return value.get();
    }

    @SuppressWarnings("unchecked")
    <R> R cache(Object key, Supplier<? extends R> value) {
        return cache(() -> key, value);
    }

    @SuppressWarnings("unchecked")
    <R> R cache(Supplier<?> key, Supplier<? extends R> value) {
        return (R) cache.computeIfAbsent(key.get(), k -> value.get());
    }
}