BoolExpression.java

/*
 * Copyright 2011-2022 B2i Healthcare Pte Ltd, http://b2i.sg
 * 
 * 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 com.b2international.index.query;

import java.util.List;
import java.util.Objects;

/**
 * @since 4.7
 */
public final class BoolExpression implements Expression {

	private final List<Expression> mustClauses;
	private final List<Expression> mustNotClauses;
	private final List<Expression> shouldClauses;
	private final List<Expression> filterClauses;
	private int minShouldMatch = 1;

	BoolExpression(List<Expression> mustClauses, List<Expression> mustNotClauses, List<Expression> shouldClauses, List<Expression> filterClauses) {
		this.mustClauses = mustClauses;
		this.mustNotClauses = mustNotClauses;
		this.shouldClauses = shouldClauses;
		this.filterClauses = filterClauses;
	}
	
	void setMinShouldMatch(int minShouldMatch) {
		this.minShouldMatch = minShouldMatch;
	}
	
	public int minShouldMatch() {
		return minShouldMatch;
	}
	
	public List<Expression> mustClauses() {
		return mustClauses;
	}
	
	public List<Expression> mustNotClauses() {
		return mustNotClauses;
	}
	
	public List<Expression> shouldClauses() {
		return shouldClauses;
	}
	
	public List<Expression> filterClauses() {
		return filterClauses;
	}
	
	@Override
	public int hashCode() {
		return Objects.hash(mustClauses, mustNotClauses, shouldClauses, filterClauses, minShouldMatch);
	}
	
	@Override
	public boolean equals(Object obj) {
		if (this == obj) return true;
		if (obj == null) return false;
		if (getClass() != obj.getClass()) return false;
		BoolExpression other = (BoolExpression) obj;
		return Objects.equals(mustClauses, other.mustClauses)
				&& Objects.equals(mustNotClauses, other.mustNotClauses)
				&& Objects.equals(shouldClauses, other.shouldClauses)
				&& Objects.equals(filterClauses, other.filterClauses)
				&& minShouldMatch == other.minShouldMatch;
	}
	
	@Override
	public String toString() {
		final StringBuilder builder = new StringBuilder();
		builder.append("BOOL(");
		
		append("MUST", mustClauses, builder);
		append("MUST NOT", mustNotClauses, builder);
		append("SHOULD", shouldClauses, builder);
		append("FILTER", filterClauses, builder);
		
		builder.append(")");
		
		return builder.toString();
	}

	private void append(final String name, final List<Expression> expressions, final StringBuilder builder) {
		if (!expressions.isEmpty()) {
			if (builder.length() > 5) {
				builder.append(", ");
			}
			
			builder.append(String.format("%s(", name));
			
			int i = 0;
			for (final Expression expression : expressions) {
				builder.append(expression);
				i++;
				
				if (i != expressions.size()) {
					builder.append(", ");
				}
			}
			
			builder.append(")");
		}
	}

	public boolean isFilterOnly() {
		return mustClauses.isEmpty() && mustNotClauses.isEmpty() && shouldClauses.isEmpty() && !filterClauses.isEmpty();
	}
	
	public boolean isShouldOnly() {
		return mustClauses.isEmpty() && mustNotClauses.isEmpty() && !shouldClauses.isEmpty() && filterClauses.isEmpty();
	}
	
}