/*******************************************************************************
 * Copyright (c) 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 ******************************************************************************/

module org.eclipse.core.internal.databinding.validation.NumberToNumberValidator;

import java.lang.all;

import org.eclipse.core.databinding.validation.IValidator;
import org.eclipse.core.databinding.validation.ValidationStatus;
import org.eclipse.core.internal.databinding.conversion.NumberToNumberConverter;
import org.eclipse.core.internal.databinding.conversion.StringToNumberParser;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;

/**
 * Base class for validators that validate if a Number can fit in another Number type.
 * <p>
 * Class is thread safe.
 * </p>
 * 
 * @since 1.0
 */
public abstract class NumberToNumberValidator : IValidator {
    private final NumberToNumberConverter converter;

    private final Number min;

    private final Number max;

    private String outOfRangeMessage;

    private final bool primitive;

    /**
     * @param converter
     * @param min
     *            can be <code>null</code>
     * @param max
     *            can be <code>null</code>
     */
    protected this(NumberToNumberConverter converter,
            Number min, Number max) {
        this.converter = converter;
        this.min = min;
        this.max = max;

        primitive = (cast(Class)converter.getToType()).isPrimitive();
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.eclipse.core.databinding.validation.IValidator#validate(java.lang.Object)
     */
    public final IStatus validate(Object value) {
        if (value is null) {
            if (primitive) {
                throw new IllegalArgumentException(
                        "Parameter 'value' cannot be null."); //$NON-NLS-1$
            }

            return Status.OK_STATUS;
        }

        if (!( null !is cast(Number)value )) {
            throw new IllegalArgumentException(
                    "Parameter 'value' is not of type Number."); //$NON-NLS-1$
        }

        Number number = cast(Number) value;
        if (inRange(number)) {
            return Status.OK_STATUS;
        }

        synchronized (this) {
            if (outOfRangeMessage is null && min !is null && max !is null) {
                outOfRangeMessage = StringToNumberParser
                        .createOutOfRangeMessage(min, max, converter
                                .getNumberFormat());
            }

            return ValidationStatus.error(outOfRangeMessage);
        }
    }

    /**
     * Invoked to determine if the value is in range.
     * 
     * @param number
     * @return <code>true</code> if in range
     */
    protected abstract bool inRange(Number number);
}