TelephoneBell

/**
 * This is open-source software licensed under the terms of the MIT License.
 *
 * Copyright (c) 2023 Petr Červinka - FortSoft <[email protected]>
 *
 * 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.
 **
 * Version 1.0.0.0
 */

using System;
using System.Diagnostics;
using System.IO;
using System.Threading.Tasks;
using System.Windows.Forms;
using WMPLib;

namespace FortSoft.Tools {

    /// <summary>
    /// Implements standard landline telephone ringing based on the Tesla P51p
    /// telephone exchange. It requires an imported MP3 file in the resources
    /// called 'Bell'. The ring duration in this file must be one second.
    /// </summary>
    public class TelephoneBell : IDisposable {

        /// <summary>
        /// The name of the destination MP3 file where the telephone bell sound
        /// will be saved and made available to Windows Media Player.
        /// </summary>
        private const string bellFileName = "Bell.mp3";

        /// <summary>
        /// Field with the full path to the extracted MP3 file with the telephone
        /// bell sound.
        /// </summary>
        private string bellFilePath;

        /// <summary>
        /// Field with a Timer object.
        /// </summary>
        private System.Timers.Timer timer;

        /// <summary>
        /// Field with Windows Media Player object.
        /// </summary>
        private WindowsMediaPlayer windowsMediaPlayer;

        /// <summary>
        /// Initializes a new instance of the <see cref="TelephoneBell"/> class.
        /// </summary>
        public TelephoneBell() {
            ExtractBellAsync();

            bellFilePath = Path.Combine(Path.GetDirectoryName(Application.LocalUserAppDataPath), bellFileName);

            windowsMediaPlayer = new WindowsMediaPlayer();

            timer = new System.Timers.Timer(5000);
            timer.Elapsed += new System.Timers.ElapsedEventHandler((sender, e) => {
                if (File.Exists(bellFilePath)) {
                    windowsMediaPlayer.controls.play();
                }
            });
        }

        /// <summary>
        /// Extracts the telephone bell sound in the MP3 file imported in the
        /// resources called 'Bell' and saves it to the application data folder
        /// as an MP3 file.
        /// </summary>
        private static async void ExtractBellAsync() {
            await Task.Run(new Action(() => {
                try {
                    string bellFilePath = Path.Combine(Path.GetDirectoryName(Application.LocalUserAppDataPath), bellFileName);
                    if (!File.Exists(bellFilePath)) {
                        File.WriteAllBytes(bellFilePath, Properties.Resources.Bell);
                    }
                } catch (Exception exception) {
                    Debug.WriteLine(exception);
                    ErrorLog.WriteLine(exception);
                }
            }));
        }

        /// <summary>
        /// Disposes the timer.
        /// </summary>
        public void Dispose() => timer.Dispose();

        /// <summary>
        /// Starts ringing.
        /// </summary>
        public void Ring() {
            windowsMediaPlayer.URL = bellFilePath;
            timer.Start();
        }

        /// <summary>
        /// Stops ringing.
        /// </summary>
        public void Stop() => timer.Stop();
    }
}