/*

 * Copyright (C) 2007-2010 Júlio Vilmar Gesser.

 * Copyright (C) 2011, 2013-2021 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.printer.concretesyntaxmodel;

import com.github.javaparser.ast.Node;

import com.github.javaparser.ast.NodeList;

import com.github.javaparser.ast.observer.ObservableProperty;

import com.github.javaparser.printer.SourcePrinter;

import java.util.Arrays;

import java.util.List;

public class CsmConditional implements CsmElement {

    private final Condition condition;

    private final List<ObservableProperty> properties;

    private final CsmElement thenElement;

    private final CsmElement elseElement;

    public Condition getCondition() {

        return condition;

    }

    public ObservableProperty getProperty() {

        if (properties.size() > 1) {

            throw new IllegalStateException();

        }

        return properties.get(0);

    }

    public List<ObservableProperty> getProperties() {

        return properties;

    }

    public CsmElement getThenElement() {

        return thenElement;

    }

    public CsmElement getElseElement() {

        return elseElement;

    }

    public enum Condition {

        IS_EMPTY,

        IS_NOT_EMPTY,

        IS_PRESENT,

        FLAG;

        boolean evaluate(Node node, ObservableProperty property){

            if (this == IS_PRESENT) {

                return !property.isNullOrNotPresent(node);

            }

            if (this == FLAG) {

                return property.getValueAsBooleanAttribute(node);

            }

            if (this == IS_EMPTY) {

                NodeList<? extends Node> value = property.getValueAsMultipleReference(node);

                return value == null || value.isEmpty();

            }

            if (this == IS_NOT_EMPTY) {

                NodeList<? extends Node> value = property.getValueAsMultipleReference(node);

                return value != null && !value.isEmpty();

            }

            throw new UnsupportedOperationException(name());

        }

    }

    public CsmConditional(ObservableProperty property, Condition condition, CsmElement thenElement, CsmElement elseElement) {

        this.properties = Arrays.asList(property);

        this.condition = condition;

        this.thenElement = thenElement;

        this.elseElement = elseElement;

    }

    public CsmConditional(List<ObservableProperty> properties, Condition condition, CsmElement thenElement, CsmElement elseElement) {

        if (properties.size() < 1) {

            throw new IllegalArgumentException();

        }

        this.properties = properties;

        this.condition = condition;

        this.thenElement = thenElement;

        this.elseElement = elseElement;

    }

    public CsmConditional(ObservableProperty property, Condition condition, CsmElement thenElement) {

        this(property, condition, thenElement, new CsmNone());

    }

    @Override

    public void prettyPrint(Node node, SourcePrinter printer) {

        boolean test = false;

        for (ObservableProperty prop : properties) {

            test = test || condition.evaluate(node, prop);

        }

        if (test) {

            thenElement.prettyPrint(node, printer);

        } else {

            elseElement.prettyPrint(node, printer);

        }

    }

}