using System;
using System.IO;
using CueSplitter.Helpers;

Console.WriteLine("Cue Command-line tool");

if (args.Length != 3) Die(-1, $"Missing args.{Environment.NewLine}Usage: CueSplitter <input_audio_file> <input_cue_file> <output_dir>");

var inputAudioFilePath = args[0];
var inputCueFilePath = args[1];
var outputDir = args[2];

if (File.Exists(inputAudioFilePath) == false) Die(-2, "Input audio file not exist");
var tag = TagLib.File.Create(inputAudioFilePath);
var duration = tag.Properties.Duration;
Console.WriteLine($"Audio file duration: {duration}");

if (File.Exists(inputCueFilePath) == false) Die(-3, "Input cue file not exist");

var cueBytes = File.ReadAllBytes(inputCueFilePath);
var encoding = TextHelper.DetectCodePage(cueBytes);
if (encoding == null) Die(-5, "Can not detect cue file text encoding");
// ReSharper disable once PossibleNullReferenceException
var cueText = encoding.GetString(cueBytes);
var tracks = CueHelper.ParseCue(cueText, duration);
Console.WriteLine($"Cue tracks number: {tracks.Length}");
var numberPaddingFormat = "".PadLeft(tracks.Length.ToString().Length, '0');
foreach (var trackModel in tracks)
{
    var d = trackModel.Duration;
    Console.WriteLine($"  {trackModel.TrackNo.ToString(numberPaddingFormat)}. {d.TotalMinutes:00}:{d.Seconds:00}.{d.Milliseconds:000} {trackModel.Title} - {trackModel.Performer}");
}

if (Directory.Exists(outputDir) == false) Die(-6, "Error: Output dir not exist");

Console.WriteLine();
Console.WriteLine("Start Extracting...");

foreach (var track in tracks)
{
    var outputFilePath = Path.Combine(
        outputDir,
        FilenameHelper.RemoveInvalidCharacters(
            $"{track.TrackNo.ToString(numberPaddingFormat)}. {track.Title}{Path.GetExtension(inputAudioFilePath)}"
        )
    );

    Console.WriteLine($"Output: {outputFilePath}");

    var ffArgs = FfMpegHelper.CutSegment(inputAudioFilePath, outputFilePath, track.Offset, track.Duration);

    FfMpegHelper.Launch(ffArgs).WaitForExit();
}

Console.WriteLine("Finished.");

return 0;

void Die(int exitCode, string errMessage = null)
{
    if (errMessage != null) Console.WriteLine($"Error: {errMessage}");
    Environment.Exit(exitCode);
}