現在演奏中のメディアファイルを列挙する

ShowPlayingFiles.cs

#nullable disable
#pragma warning disable 

using System.Diagnostics;
using System.Net.NetworkInformation;
using System.Reflection;
using System.Security.Principal;
using System.Text;
using System.Text.RegularExpressions;
using NAudio.CoreAudioApi;
//
// NAudio を nuget から、handle.exe(DBCS対応版)を下の URL から入手してください。
// https://github.com/PolarGoose/Sysinternals-console-utils-with-Unicode-support/releases
//
static class Program
{
    // result:
    // vlc                        C:\Temp\A.mp3
    // wmplayer                   C:\Temp\B.mp3
    // Microsoft.Media.Player     C:\Temp\日本語.mp3
    [STAThread]
    static void Main() {
        // If the program is not started as an administrator, grant it and start it.
        // You can also set the following in the application manifest.
        // <requestedExecutionLevel level="requireAdministrator" uiAccess="false" />
        if (!IsAdministratorRights) {
            StartAdministratorRights();
            return;
        }

        // Enumerate devices
        var deviceEnumerator = new MMDeviceEnumerator();
        foreach (var device in deviceEnumerator.EnumerateAudioEndPoints(
                                    DataFlow.Render, DeviceState.Active)) {
            // Sessions with the device open
            // SessionCollection is not implements IEnumurable :( 
            var sessionManager = device.AudioSessionManager;
            var sessions = sessionManager.Sessions;
            for (int i = 0; i < sessions.Count; i++) {
                var session = sessions[i];
                var volume = session.AudioMeterInformation.MasterPeakValue;
                if (volume > 0) {
                    using (var process = Process.GetProcessById((int)session.GetProcessID)) {
                        var fileName = GetUseMultimediaFile(process);
                        if (fileName != null) {
                            Console.WriteLine($"{process.ProcessName.PadRight(26)} {fileName}");
                        }
                    }
                }
            }
        }
    }

    private static bool IsAdministratorRights {
        get {
            using (var identity = WindowsIdentity.GetCurrent()) {
                var principal = new WindowsPrincipal(identity);
                return principal.IsInRole(WindowsBuiltInRole.Administrator);
            }
        }
    }

    private static void StartAdministratorRights() {
        var myProgramName = Path.ChangeExtension(Assembly.GetEntryAssembly().Location, ".exe");
        var tempFileName = Path.GetTempFileName();
        ProcessStartInfo info = new ProcessStartInfo();
        info.FileName = "cmd.exe";
        info.Arguments = $"/C \"\"\"{myProgramName}\"\" > {tempFileName}\"";
        info.CreateNoWindow = false;
        info.UseShellExecute = true;
        info.Verb = "RunAs";
        using (var process = Process.Start(info)) {
            process.WaitForExit();
            Console.WriteLine(File.ReadAllText(tempFileName));
            File.Delete(tempFileName);
        }
    }

    private static string[] MultimediaExtensions = [
            "mp3","wav","flac","aac","ogg","m4a","wma","alac",
            "aiff","opus","pcm","dsd","ape","mpc","wv",
            "avi","mp4","mkv","flv","mov","wmv","webm","mpeg","mpg",
            "m4v","3gp","vob","ogv","rm","rmvb","mts","m2ts","ts",
        ];

    private static string MultimediaPattern {
        get {
            var sb = new StringBuilder();
            foreach (var s in MultimediaExtensions) {
                sb.Append($"|\\.{s}");
            }
            return sb.ToString(2, sb.Length - 2);
        }
    }

    // If non-English characters are garbled,
    // download the unicode version from
    // https://github.com/PolarGoose/Sysinternals-console-utils-with-Unicode-support/releases
    // However, it appears that it is not Unicode compatible, but only DBCS compatible.

    private static string GetUseMultimediaFile(Process process) {
        var psi = new ProcessStartInfo();
        psi.UseShellExecute = false;
        psi.FileName = "cmd.exe";
        psi.RedirectStandardInput = true;
        psi.RedirectStandardOutput = true;
        psi.StandardInputEncoding = Encoding.Default;
        psi.StandardOutputEncoding = Encoding.Default;
        using (var p = Process.Start(psi)) {
            using (var writer = p.StandardInput) {
                writer.WriteLine($"handle64_v5.0_Unicode.exe -vt -p {process.Id}");
            }
            using (var reader = p.StandardOutput) {
                var alines = reader.ReadToEnd();
                p.WaitForExit();
                var lines = alines.Split("\r\n");
                var line = lines.Where(line => Regex.IsMatch(line, 
                                                        MultimediaPattern,
                                                        RegexOptions.IgnoreCase))
                                .FirstOrDefault();
                if (line != null) {
                    return line.Split("\t")[6];
                }
            }
            return null;
        }
    }
}