using System;
using System.Linq;
using System.Runtime.InteropServices;
using System.Threading;
using System.Windows.Forms;
using VideoPlayLib;

namespace Demo
{
    public partial class MainForm: Form
    {
        private VideoPlay _vp;
        private Form _big;

        public MainForm()
        {
            InitializeComponent();
        }

        #region 自定义消息

        protected override void WndProc(ref Message m)
        {
            MsgPostProc(m);
            base.WndProc(ref m);
        }

        private const int WM_USER = 0x0400;
        private const int MSG_PLAY = WM_USER + 101;

        [DllImport("User32.dll")]
        private static extern int PostMessage(
            IntPtr hWnd, // handle to destination window
            uint msg, // message
            uint wParam, // first message parameter
            uint lParam // second message parameter
        );

        private string MsgPostUrl;

        private void MsgPostPlay(string url)
        {
            MsgPostUrl = url;
            new Thread(
                () => Invoke(
                    new Action(
                        () =>
                            PostMessage(Handle, MSG_PLAY, 0, 0)
                    )
                )
            ).Start();
        }

        private void MsgPostProc(Message p)
        {
            if (p.Msg != MSG_PLAY)
                return;

            LoadMediaFile();

            MsgPostUrl = null;
        }

        #endregion 自定义消息

        private void MainForm_Shown(object sender, EventArgs e)
        {
            _big = new Form();
            _big.Show();
            _big.Location = Screen.AllScreens[0].Bounds.Location;
            _big.WindowState = FormWindowState.Maximized;
            _big.FormBorderStyle = FormBorderStyle.None;
        }

        private void btnLoad_DragEnter(object sender, DragEventArgs e)
        {
            e.Effect = e.Data.GetDataPresent(DataFormats.FileDrop)
                ? DragDropEffects.Link
                : DragDropEffects.None;
        }

        private void btnLoad_DragDrop(object sender, DragEventArgs e)
        {
            var filename = ((string[])e.Data.GetData(DataFormats.FileDrop)).First();

            MsgPostPlay(filename);
        }

        private void LoadMediaFile()
        {
            tmrProgress.Stop();

            if (_vp != null)
                _vp.Dispose();

            _vp = new VideoPlay(MsgPostUrl, pnlVideo, _big);

            cboAudioTracks.DataSource = _vp.Audios;

            trkProgress.Minimum = 0;
            trkProgress.Maximum = (int)(_vp.Duration * 10);
            trkProgress.Value = 0;
        }

        private void btnPlay_Click(object sender, EventArgs e)
        {
            _vp.Play();
            tmrProgress.Start();
        }

        private void btnPause_Click(object sender, EventArgs e)
        {
            _vp.Pause();
            tmrProgress.Stop();
        }

        private void cboAudioTracks_SelectedIndexChanged(object sender, EventArgs e)
        {
            _vp.SetAudio(cboAudioTracks.SelectedIndex);
        }

        private void tmrProgress_Tick(object sender, EventArgs e)
        {
            trkProgress.Value = (int)(_vp.CurrentPosition * 10);
        }
    }
}