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/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2017 Marc de Verdelhan, 2017-2019 Ta4j Organization & respective
 * authors (see AUTHORS)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
package org.ta4j.core;

import org.ta4j.core.trading.rules.AndRule;
import org.ta4j.core.trading.rules.NotRule;
import org.ta4j.core.trading.rules.OrRule;
import org.ta4j.core.trading.rules.XorRule;

/**
 * A rule for strategy building.
 *
 * A trading rule may be composed of a combination of other rules.
 *
 * A {@link Strategy trading strategy} is a pair of complementary (entry and
 * exit) rules.
 */
public interface Rule {

    /**
     * @param rule another trading rule
     * @return a rule which is the AND combination of this rule with the provided
     *         one
     */
    default Rule and(Rule rule) {
        return new AndRule(this, rule);
    }

    /**
     * @param rule another trading rule
     * @return a rule which is the OR combination of this rule with the provided one
     */
    default Rule or(Rule rule) {
        return new OrRule(this, rule);
    }

    /**
     * @param rule another trading rule
     * @return a rule which is the XOR combination of this rule with the provided
     *         one
     */
    default Rule xor(Rule rule) {
        return new XorRule(this, rule);
    }

    /**
     * @return a rule which is the logical negation of this rule
     */
    default Rule negation() {
        return new NotRule(this);
    }

    /**
     * @param index the bar index
     * @return true if this rule is satisfied for the provided index, false
     *         otherwise
     */
    default boolean isSatisfied(int index) {
        return isSatisfied(index, null);
    }

    /**
     * @param index         the bar index
     * @param tradingRecord the potentially needed trading history
     * @return true if this rule is satisfied for the provided index, false
     *         otherwise
     */
    boolean isSatisfied(int index, TradingRecord tradingRecord);
}