/*

 * 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.ast.expr;

import com.github.javaparser.TokenRange;

import com.github.javaparser.ast.AllFieldsConstructor;

import com.github.javaparser.ast.Generated;

import com.github.javaparser.ast.Node;

import com.github.javaparser.ast.visitor.CloneVisitor;

import com.github.javaparser.ast.visitor.GenericVisitor;

import com.github.javaparser.ast.visitor.VoidVisitor;

import com.github.javaparser.metamodel.JavaParserMetaModel;

import com.github.javaparser.metamodel.LongLiteralExprMetaModel;

import java.math.BigInteger;

import java.util.Objects;

import java.util.Optional;

import java.util.function.Consumer;

import static com.github.javaparser.utils.Utils.hasUnaryMinusAsParent;

/**

 * All ways to specify a long literal.

 *

 * <ul>

 * <li>{@code 8934l}</li>

 * <li>{@code 0x01L}</li>

 * <li>{@code 022l}</li>

 * <li>{@code 0B10101010L}</li>

 * <li>{@code 99999999L}</li>

 * </ul>

 *

 * @author Julio Vilmar Gesser

 */

public class LongLiteralExpr extends LiteralStringValueExpr {

    public static final String MAX_63_BIT_UNSIGNED_VALUE_AS_STRING = "9223372036854775808L";

    public static final BigInteger MAX_63_BIT_UNSIGNED_VALUE_AS_BIG_INTEGER = new BigInteger("9223372036854775808");

    public LongLiteralExpr() {

        this(null, "0");

    }

    @AllFieldsConstructor

    public LongLiteralExpr(final String value) {

        this(null, value);

    }

    /**

     * This constructor is used by the parser and is considered private.

     */

    @Generated("com.github.javaparser.generator.core.node.MainConstructorGenerator")

    public LongLiteralExpr(TokenRange tokenRange, String value) {

        super(tokenRange, value);

        customInitialization();

    }

    /**

     * @deprecated This function is deprecated in favor of {@link #LongLiteralExpr(String)}. Please refer to the {@link

     * #asNumber()} function for valid formats and how to construct literals holding negative values.

     */

    @Deprecated

    public LongLiteralExpr(final long value) {

        this(null, String.valueOf(value));

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.AcceptGenerator")

    public <R, A> R accept(final GenericVisitor<R, A> v, final A arg) {

        return v.visit(this, arg);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.AcceptGenerator")

    public <A> void accept(final VoidVisitor<A> v, final A arg) {

        v.visit(this, arg);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.RemoveMethodGenerator")

    public boolean remove(Node node) {

        if (node == null)

            return false;

        return super.remove(node);

    }

    /**

     * @return the literal value as an long while respecting different number representations

     * @deprecated This function has issues with corner cases, such as 9223372036854775808L, so please use {@link

     * LongLiteralExpr#asNumber()}. It will be made private or merged with {@link LongLiteralExpr#asNumber()} in future

     * releases

     */

    @Deprecated

    public long asLong() {

        String result = value.replaceAll("_", "");

        char lastChar = result.charAt(result.length() - 1);

        if (lastChar == 'l' || lastChar == 'L') {

            result = result.substring(0, result.length() - 1);

        }

        if (result.startsWith("0x") || result.startsWith("0X")) {

            return Long.parseUnsignedLong(result.substring(2), 16);

        }

        if (result.startsWith("0b") || result.startsWith("0B")) {

            return Long.parseUnsignedLong(result.substring(2), 2);

        }

        if (result.length() > 1 && result.startsWith("0")) {

            return Long.parseUnsignedLong(result.substring(1), 8);

        }

        return Long.parseLong(result);

    }

    /**

     * This function returns a representation of the literal value as a number. This will return a long, except for the

     * case when the literal has the value {@code 9223372036854775808L}. This special literal is only allowed in

     * the expression {@code -9223372036854775808L} which represents <code>Long.MIN_VALUE</code>). However

     * 9223372036854775808 (2^63) is out of range of long, which is -(2^63) to (2^63)-1 and thus a BigInteger must be

     * returned.

     *

     * <p>Note, that this function will NOT return a negative number if the literal was specified in decimal, since

     * according to the language specification (chapter 3.10.1) an expression such as {@code -1L} is represented by

     * a unary * expression with a minus operator and the literal {@code 1L}. It is however possible to represent

     * negative * numbers in a literal directly,  i.e. by using the binary or hexadecimal representation. For example

     * {@code 0xffff_ffff_ffff_ffffL} represents the value <code>-1L</code>.

     *

     * @return the literal value as a number while respecting different number representations

     */

    public Number asNumber() {

        /* we need to handle the special case for the literal 9223372036854775808L, which is used to

         * represent Integer.MIN_VALUE (-9223372036854775808L) as a combination of a UnaryExpr and a

         * LongLiteralExpr. However 9223372036854775808L cannot be represented in a long, so we need

         * to return a BigInteger

         */

        if (Objects.equals(value, MAX_63_BIT_UNSIGNED_VALUE_AS_STRING) && hasUnaryMinusAsParent(this)) {

            return MAX_63_BIT_UNSIGNED_VALUE_AS_BIG_INTEGER;

        } else {

            return asLong();

        }

    }

    /**

     * @deprecated This function is deprecated in favor of {@link #setValue(String)}. Please refer to the {@link

     * #asNumber()} function for valid formats and how to construct literals holding negative values.

     */

    @Deprecated

    public LongLiteralExpr setLong(long value) {

        this.value = String.valueOf(value);

        return this;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.CloneGenerator")

    public LongLiteralExpr clone() {

        return (LongLiteralExpr) accept(new CloneVisitor(), null);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.GetMetaModelGenerator")

    public LongLiteralExprMetaModel getMetaModel() {

        return JavaParserMetaModel.longLiteralExprMetaModel;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.ReplaceMethodGenerator")

    public boolean replace(Node node, Node replacementNode) {

        if (node == null)

            return false;

        return super.replace(node, replacementNode);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public boolean isLongLiteralExpr() {

        return true;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public LongLiteralExpr asLongLiteralExpr() {

        return this;

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public void ifLongLiteralExpr(Consumer<LongLiteralExpr> action) {

        action.accept(this);

    }

    @Override

    @Generated("com.github.javaparser.generator.core.node.TypeCastingGenerator")

    public Optional<LongLiteralExpr> toLongLiteralExpr() {

        return Optional.of(this);

    }

}