///////////////////////////////////////////////////////////////////////////
//                   __                _      _   ________               //
//                  / /   ____  ____ _(_)____/ | / / ____/               //
//                 / /   / __ \/ __ `/ / ___/  |/ / / __                 //
//                / /___/ /_/ / /_/ / / /__/ /|  / /_/ /                 //
//               /_____/\____/\__, /_/\___/_/ |_/\____/                  //
//                           /____/                                      //
//                                                                       //
//               The Next Generation Logic Library                       //
//                                                                       //
///////////////////////////////////////////////////////////////////////////
//                                                                       //
//  Copyright 2015-20xx Christoph Zengler                                //
//                                                                       //
//  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.logicng.functions;

import static org.assertj.core.api.Assertions.assertThat;

import org.junit.jupiter.api.Test;
import org.logicng.TestWithExampleFormulas;
import org.logicng.formulas.Formula;
import org.logicng.formulas.FormulaFactory;
import org.logicng.formulas.Variable;
import org.logicng.formulas.cache.FunctionCacheEntry;

/**
 * Unit Tests for the class {@link FormulaDepthFunction}.
 * @version 2.0.0
 * @since 2.0.0
 */
public class FormulaDepthFunctionTest extends TestWithExampleFormulas {

    @Test
    public void testAtoms() {
        assertThat(this.TRUE.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.FALSE.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.A.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.NA.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.PBC1.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.PBC2.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.PBC3.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.PBC4.apply(FormulaDepthFunction.get())).isEqualTo(0);
        assertThat(this.PBC5.apply(FormulaDepthFunction.get())).isEqualTo(0);
    }

    @Test
    public void testDeepFormulas() {
        assertThat(this.AND1.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.AND2.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.AND3.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.OR1.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.OR2.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.OR3.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.NOT1.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.NOT2.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.IMP1.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.IMP2.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.IMP3.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.IMP4.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.EQ1.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.EQ2.apply(FormulaDepthFunction.get())).isEqualTo(1);
        assertThat(this.EQ3.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(this.EQ4.apply(FormulaDepthFunction.get())).isEqualTo(2);
    }

    @Test
    public void testDeeperFormulas() {
        Formula formula = this.PBC1;
        for (int i = 0; i < 10; i++) {
            final Variable var = this.f.variable("X" + i);
            formula = i % 2 == 0 ? this.f.or(formula, var) : this.f.and(formula, var);
        }
        assertThat(formula.apply(FormulaDepthFunction.get())).isEqualTo(10);
    }

    @Test
    public void testCache() {
        final FormulaFactory f = new FormulaFactory();
        final Formula formula = parse(f, "A & B | C");
        assertThat(formula.functionCacheEntry(FunctionCacheEntry.DEPTH)).isNull();
        assertThat(formula.apply(FormulaDepthFunction.get())).isEqualTo(2);
        assertThat(formula.functionCacheEntry(FunctionCacheEntry.DEPTH)).isEqualTo(2);
        assertThat(f.variable("A").functionCacheEntry(FunctionCacheEntry.DEPTH)).isEqualTo(0);

        formula.setFunctionCacheEntry(FunctionCacheEntry.DEPTH, 3);
        assertThat(formula.apply(FormulaDepthFunction.get())).isEqualTo(3);
    }
}
