/**
 * Author: Sven Gothel <sgothel@jausoft.com>
 * Copyright (c) 2020 Gothel Software e.K.
 * Copyright (c) 2020 ZAFENA AB
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package jau.direct_bt;

import java.lang.ref.WeakReference;
import java.util.List;

import org.direct_bt.BTDevice;
import org.direct_bt.BTGattChar;
import org.direct_bt.BTGattDesc;
import org.direct_bt.BTGattService;
import org.direct_bt.BTObject;
import org.direct_bt.BTType;

public class DBTGattService extends DBTObject implements BTGattService
{
    /** Service's device weak back-reference */
    final WeakReference<DBTDevice> wbr_device;

    private final boolean isPrimary;
    private final String type_uuid;
    private final short handleStart;
    private final short handleEnd;
    /* pp */ final List<BTGattChar> charList;

   /* pp */ DBTGattService(final long nativeInstance, final DBTDevice device, final boolean isPrimary,
                           final String type_uuid, final short handleStart, final short handleEnd)
    {
        super(nativeInstance, compHash(handleStart, handleEnd));
        this.wbr_device = new WeakReference<DBTDevice>(device);
        this.isPrimary = isPrimary;
        this.type_uuid = type_uuid;
        this.handleStart = handleStart;
        this.handleEnd = handleEnd;
        this.charList = getCharsImpl();
    }

    @Override
    public boolean equals(final Object obj)
    {
        if (obj == null || !(obj instanceof DBTGattService)) {
            return false;
        }
        final DBTGattService other = (DBTGattService)obj;
        return handleStart == other.handleStart && handleEnd == other.handleEnd; /** unique attribute handles */
    }

    @Override
    public String getUUID() { return type_uuid; }

    @Override
    public BTType getBluetoothType() { return class_type(); }

    static BTType class_type() { return BTType.GATT_SERVICE; }

    @Override
    public final BTGattService clone()
    { throw new UnsupportedOperationException(); } // FIXME

    @Override
    public BTGattChar find(final String UUID, final long timeoutMS) {
        if( !checkServiceCache() ) {
            return null;
        }
        return (DBTGattChar) findInCache(UUID, BTType.GATT_CHARACTERISTIC);
    }

    @Override
    public BTGattChar find(final String UUID) {
        return find(UUID, 0);
    }

    @Override
    public final BTDevice getDevice() { return wbr_device.get(); }

    @Override
    public final boolean getPrimary() { return isPrimary; }

    @Override
    public final List<BTGattChar> getChars() { return charList; }

    /**
     * Returns the service start handle.
     * <p>
     * Attribute handles are unique for each device (server) (BT Core Spec v5.2: Vol 3, Part F Protocol..: 3.2.2 Attribute Handle).
     * </p>
     */
    public final short getHandleStart() { return handleStart; }

    /**
     * Returns the service end handle.
     * <p>
     * Attribute handles are unique for each device (server) (BT Core Spec v5.2: Vol 3, Part F Protocol..: 3.2.2 Attribute Handle).
     * </p>
     */
    public final short getHandleEnd() { return handleEnd; }

    @Override
    public final String toString() {
        if( !isValid() ) {
            return "Service" + "\u271D" + "[uuid "+getUUID()+", handles [0x"+Integer.toHexString(handleStart)+".."+Integer.toHexString(handleEnd)+"]]";
        }
        return toStringImpl();
    }

    /* Native method calls: */

    private native String toStringImpl();

    private native List<BTGattChar> getCharsImpl();

    @Override
    protected native void deleteImpl(long nativeInstance);

    /* local functionality */

    /* pp */ boolean checkServiceCache() {
        final DBTDevice device = wbr_device.get();
        return null != device && device.checkServiceCache(false);
    }

    /**
     * Returns the matching {@link DBTObject} from the internal cache if found,
     * otherwise {@code null}.
     * <p>
     * The returned {@link DBTObject} may be of type
     * <ul>
     *   <li>{@link DBTGattChar}</li>
     *   <li>{@link DBTGattDesc}</li>
     * </ul>
     * or alternatively in {@link BTObject} space
     * <ul>
     *   <li>{@link BTType#GATT_CHARACTERISTIC} -> {@link BTGattChar}</li>
     *   <li>{@link BTType#GATT_DESCRIPTOR} -> {@link BTGattDesc}</li>
     * </ul>
     * </p>
     * @param uuid UUID of the desired
     * {@link BTType#GATT_CHARACTERISTIC characteristic} or {@link BTType#GATT_DESCRIPTOR descriptor} to be found.
     * Maybe {@code null}, in which case the first object of the desired type is being returned - if existing.
     * @param type specify the type of the object to be found, either
     * {@link BTType#GATT_CHARACTERISTIC characteristic}
     * or {@link BTType#GATT_DESCRIPTOR descriptor}.
     * {@link BTType#NONE none} means anything.
     */
    /* pp */ DBTObject findInCache(final String uuid, final BTType type) {
        final boolean anyType = BTType.NONE == type;
        final boolean charType = BTType.GATT_CHARACTERISTIC== type;
        final boolean descType = BTType.GATT_DESCRIPTOR == type;

        if( !anyType && !charType && !descType ) {
            return null;
        }
        final int characteristicSize = charList.size();
        for(int charIdx = 0; charIdx < characteristicSize; charIdx++ ) {
            final DBTGattChar characteristic = (DBTGattChar) charList.get(charIdx);
            if( ( anyType || charType ) && ( null == uuid || characteristic.getUUID().equals(uuid) ) ) {
                return characteristic;
            }
            if( anyType || descType ) {
                final DBTObject dbtObj = characteristic.findInCache(uuid, type);
                if( null != dbtObj ) {
                    return dbtObj;
                }
            }
        }
        return null;
    }

}