/* -LICENSE-START-
** Copyright (c) 2018 Blackmagic Design
**  
** Permission is hereby granted, free of charge, to any person or organization 
** obtaining a copy of the software and accompanying documentation (the 
** "Software") to use, reproduce, display, distribute, sub-license, execute, 
** and transmit the Software, and to prepare derivative works of the Software, 
** and to permit third-parties to whom the Software is furnished to do so, in 
** accordance with:
** 
** (1) if the Software is obtained from Blackmagic Design, the End User License 
** Agreement for the Software Development Kit ("EULA") available at 
** https://www.blackmagicdesign.com/EULA/DeckLinkSDK; or
** 
** (2) if the Software is obtained from any third party, such licensing terms 
** as notified by that third party,
** 
** and all subject to the following:
** 
** (3) the copyright notices in the Software and this entire statement, 
** including the above license grant, this restriction and the following 
** disclaimer, must be included in all copies of the Software, in whole or in 
** part, and all derivative works of the Software, unless such copies or 
** derivative works are solely in the form of machine-executable object code 
** generated by a source language processor.
** 
** (4) 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, TITLE AND NON-INFRINGEMENT. IN NO EVENT 
** SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE 
** FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, 
** ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
** DEALINGS IN THE SOFTWARE.
** 
** A copy of the Software is available free of charge at 
** https://www.blackmagicdesign.com/desktopvideo_sdk under the EULA.
** 
** -LICENSE-END-
*/

using System;
using DeckLinkAPI;

namespace StillsCSharp
{
    public class DeckLinkDiscoveryEventArgs : EventArgs
    {
        public readonly IDeckLink deckLink;

        public DeckLinkDiscoveryEventArgs(IDeckLink deckLink)
        {
            this.deckLink = deckLink;
        }
    }

    public class DeckLinkDeviceDiscovery : IDeckLinkDeviceNotificationCallback
    {
        private IDeckLinkDiscovery m_deckLinkDiscovery;
        private bool m_deckLinkDiscoveryEnabled = false;

        public event EventHandler<DeckLinkDiscoveryEventArgs> DeviceArrived;
        public event EventHandler<DeckLinkDiscoveryEventArgs> DeviceRemoved;

        public DeckLinkDeviceDiscovery()
        {
            m_deckLinkDiscovery = new CDeckLinkDiscovery();
        }

        ~DeckLinkDeviceDiscovery()
        {
            Disable();
        }

        public void Enable()
        {
            m_deckLinkDiscovery.InstallDeviceNotifications(this);
            m_deckLinkDiscoveryEnabled = true;
        }

        public void Disable()
        {
            if (m_deckLinkDiscoveryEnabled)
            { 
                m_deckLinkDiscovery.UninstallDeviceNotifications();
                m_deckLinkDiscoveryEnabled = false;
            }
        }

        #region callbacks
        void IDeckLinkDeviceNotificationCallback.DeckLinkDeviceArrived(IDeckLink deckLinkDevice)
        {
            EventHandler<DeckLinkDiscoveryEventArgs> handler = DeviceArrived;

            // Check whether there are any subscribers to DeviceArrived event
            if (handler != null)
            {
                handler(this, new DeckLinkDiscoveryEventArgs(deckLinkDevice));
            }
        }

        void IDeckLinkDeviceNotificationCallback.DeckLinkDeviceRemoved(IDeckLink deckLinkDevice)
        {
            EventHandler<DeckLinkDiscoveryEventArgs> handler = DeviceRemoved;

            // Check whether there are any subscribers to DeviceRemoved event
            if (handler != null)
            {
                handler(this, new DeckLinkDiscoveryEventArgs(deckLinkDevice));
            }
        }
        #endregion
    }
}