/*
 * Copyright (C) 2015-2016 Federico Tomassetti
 * Copyright (C) 2017-2024 The JavaParser Team.
 *
 * This file is part of JavaParser.
 *
 * JavaParser can be used either under the terms of
 * a) the GNU Lesser General Public License as published by
 *     the Free Software Foundation, either version 3 of the License, or
 *     (at your option) any later version.
 * b) the terms of the Apache License
 *
 * You should have received a copy of both licenses in LICENCE.LGPL and
 * LICENCE.APACHE. Please refer to those files for details.
 *
 * JavaParser is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 */

package com.github.javaparser.symbolsolver.resolution.typeinference.constraintformulas;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.Mockito.mock;

import com.github.javaparser.ast.expr.Expression;
import com.github.javaparser.ast.expr.StringLiteralExpr;
import com.github.javaparser.resolution.TypeSolver;
import com.github.javaparser.resolution.declarations.ResolvedTypeParameterDeclaration;
import com.github.javaparser.resolution.model.typesystem.ReferenceTypeImpl;
import com.github.javaparser.resolution.types.ResolvedType;
import com.github.javaparser.symbolsolver.resolution.typeinference.BoundSet;
import com.github.javaparser.symbolsolver.resolution.typeinference.ConstraintFormula;
import com.github.javaparser.symbolsolver.resolution.typeinference.InferenceVariable;
import com.github.javaparser.symbolsolver.resolution.typesolvers.ReflectionTypeSolver;
import org.junit.jupiter.api.Test;

class ConstraintFormulaTest {

    private TypeSolver typeSolver = new ReflectionTypeSolver();
    private ResolvedType stringType =
            new ReferenceTypeImpl(new ReflectionTypeSolver().solveType(String.class.getCanonicalName()));

    /**
     * From JLS 18.1.2
     *
     * From Collections.singleton("hi"), we have the constraint formula ‹"hi" → α›.
     * Through reduction, this will become the constraint formula: ‹String <: α›.
     */
    @Test
    void testExpressionCompatibleWithTypeReduce1() {
        ResolvedTypeParameterDeclaration tp = mock(ResolvedTypeParameterDeclaration.class);

        Expression e = new StringLiteralExpr("hi");
        InferenceVariable inferenceVariable = new InferenceVariable("α", tp);

        ExpressionCompatibleWithType formula = new ExpressionCompatibleWithType(typeSolver, e, inferenceVariable);

        ConstraintFormula.ReductionResult res1 = formula.reduce(BoundSet.empty());
        assertEquals(
                ConstraintFormula.ReductionResult.empty()
                        .withConstraint(new TypeCompatibleWithType(typeSolver, stringType, inferenceVariable)),
                res1);

        assertEquals(
                ConstraintFormula.ReductionResult.empty()
                        .withConstraint(new TypeSubtypeOfType(typeSolver, stringType, inferenceVariable)),
                res1.getConstraint(0).reduce(BoundSet.empty()));
    }

    //    /**
    //     * From JLS 18.1.2
    //     *
    //     * From Arrays.asList(1, 2.0), we have the constraint formulas ‹1 → α› and ‹2.0 → α›. Through reduction,
    //     * these will become the constraint formulas ‹int → α› and ‹double → α›, and then ‹Integer <: α› and ‹Double
    // <: α›.
    //     */
    //    @Test
    //    public void testExpressionCompatibleWithTypeReduce2() {
    //        throw new UnsupportedOperationException();
    //    }
    //
    //    /**
    //     * From JLS 18.1.2
    //     *
    //     * From the target type of the constructor invocation List<Thread> lt = new ArrayList<>(), we have the
    // constraint
    //     * formula ‹ArrayList<α> → List<Thread>›. Through reduction, this will become the constraint formula ‹α <=
    // Thread›,
    //     * and then ‹α = Thread›.
    //     */
    //    @Test
    //    public void testExpressionCompatibleWithTypeReduce3() {
    //        throw new UnsupportedOperationException();
    //    }
}
