using System;

using System.Collections.Generic;

using System.IO;

using System.Threading.Tasks.Dataflow;

namespace DataFlowSample

{

    class Program

    {

        static void Main()

        {

            var target = SetupPipeline();

            target.Post(@"D:\Source\BenchmarkAndSpanExample-master\BenchmarkAndSpanExample");

            Console.ReadLine();

        }

        public static IEnumerable<string> GetFileNames(string path)

        {

            foreach (var fileName in Directory.EnumerateFiles(path, "*.cs"))

            {

                yield return fileName;

            }

        }

        public static IEnumerable<string> LoadLines(IEnumerable<string> fileNames)

        {

            foreach (var fileName in fileNames)

            {

                using (FileStream stream = File.OpenRead(fileName))

                {

                    var reader = new StreamReader(stream);

                    string line = null;

                    while ((line = reader.ReadLine()) != null)

                    {

                        //WriteLine($"LoadLines {line}");

                        yield return line;

                    }

                }

            }

        }

        public static IEnumerable<string> GetWords(IEnumerable<string> lines)

        {

            foreach (var line in lines)

            {

                string[] words = line.Split(' ', ';', '(', ')', '{', '}', '.', ',');

                foreach (var word in words)

                {

                    if (!string.IsNullOrEmpty(word))

                        yield return word;

                }

            }

        }

        public static ITargetBlock<string> SetupPipeline()

        {

            var fileNamesForPath = new TransformBlock<string, IEnumerable<string>>(

              path => GetFileNames(path));

            var lines = new TransformBlock<IEnumerable<string>, IEnumerable<string>>(

              fileNames => LoadLines(fileNames));

            var words = new TransformBlock<IEnumerable<string>, IEnumerable<string>>(

              lines2 => GetWords(lines2));

            var display = new ActionBlock<IEnumerable<string>>(

              coll =>

              {

                  foreach (var s in coll)

                  {

                      Console.WriteLine(s);

                  }

              });

            fileNamesForPath.LinkTo(lines);

            lines.LinkTo(words);

            words.LinkTo(display);

            return fileNamesForPath;

        }

    }

}