/*
 * Copyright 2013 Klaus Reimer <k@ailis.de>
 * See LICENSE.md for licensing information.
 *
 * Based on libusb <http://www.libusb.org/>:
 *
 * Copyright 2001 Johannes Erdfelt <johannes@erdfelt.com>
 * Copyright 2007-2009 Daniel Drake <dsd@gentoo.org>
 * Copyright 2010-2012 Peter Stuge <peter@stuge.se>
 * Copyright 2008-2011 Nathan Hjelm <hjelmn@users.sourceforge.net>
 * Copyright 2009-2012 Pete Batard <pete@akeo.ie>
 * Copyright 2009-2012 Ludovic Rousseau <ludovic.rousseau@gmail.com>
 * Copyright 2010-2012 Michael Plante <michael.plante@gmail.com>
 * Copyright 2011-2012 Hans de Goede <hdegoede@redhat.com>
 * Copyright 2012 Martin Pieuchot <mpi@openbsd.org>
 * Copyright 2012-2013 Toby Gray <toby.gray@realvnc.com>
 */

package org.usb4java.libusb;

import java.nio.ByteBuffer;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;

import org.usb4java.utils.DescriptorUtils;

/**
 * A generic representation of a BOS Device Capability descriptor.
 *
 * It is advised to check bDevCapabilityType and call the matching
 * get*Descriptor method to get a structure fully matching the type.
 *
 * @author Klaus Reimer (k@ailis.de)
 */
public final class BosDevCapabilityDescriptor
{
    /** The native pointer to the descriptor structure. */
    private long bosDevCapabilityDescriptorPointer;

    /**
     * Package-private constructor to prevent manual instantiation. BOS device
     * capability descriptors are always created by JNI.
     */
    BosDevCapabilityDescriptor()
    {
        // Empty
    }

    /**
     * Returns the native pointer.
     *
     * @return The native pointer.
     */
    public long getPointer()
    {
        return this.bosDevCapabilityDescriptorPointer;
    }

    /**
     * Returns the size of this descriptor (in bytes).
     *
     * @return The descriptor size in bytes;
     */
    public native byte bLength();

    /**
     * Returns the descriptor type.
     *
     * @return The descriptor type.
     */
    public native byte bDescriptorType();

    /**
     * Returns the device capability type.
     *
     * @return The device capability type.
     */
    public native byte bDevCapabilityType();

    /**
     * Returns the device capability data (bLength - 3 bytes).
     *
     * @return The device capability data.
     */
    public native ByteBuffer devCapabilityData();

    /**
     * Returns a dump of this descriptor.
     *
     * @return The descriptor dump.
     */
    public String dump()
    {
        return String.format(
            "BOS Device Capability Descriptor:%n" +
            "  bLength %18d%n" +
            "  bDescriptorType %10d%n" +
            "  bDevCapabilityType %7s%n" +
            "  devCapabilityData:%n%s%n",
            this.bLength() & 0xFF,
            this.bDescriptorType() & 0xFF,
            this.bDevCapabilityType() & 0xFF,
            DescriptorUtils.dump(this.devCapabilityData())
                .replaceAll("(?m)^", "    "));
    }

    @Override
    public int hashCode()
    {
        return new HashCodeBuilder()
            .append(this.bLength())
            .append(this.bDescriptorType())
            .append(this.bDevCapabilityType())
            .append(this.devCapabilityData())
            .toHashCode();
    }

    @Override
    public boolean equals(final Object obj)
    {
        if (obj == null)
        {
            return false;
        }
        if (obj == this)
        {
            return true;
        }
        if (obj.getClass() != this.getClass())
        {
            return false;
        }

        final BosDevCapabilityDescriptor other = (BosDevCapabilityDescriptor) obj;

        return new EqualsBuilder()
            .append(this.bLength(), other.bLength())
            .append(this.bDescriptorType(), other.bDescriptorType())
            .append(this.bDevCapabilityType(), other.bDevCapabilityType())
            .append(this.devCapabilityData(), other.devCapabilityData()).
            isEquals();
    }

    @Override
    public String toString()
    {
        return this.dump();
    }
}