using System;
using System.Collections.Generic;
using System.IO;

namespace Sony.Filtr.Tasks.Tasks.Spotify
{
    public class NewPlaylistsFromFolderReader : NewPlaylistsReader
    {
        public readonly string FolderPath;
        public readonly string FileSearchPattern;

        public NewPlaylistsFromFolderReader(string folderPath, string fileSearchPattern)
        {
            if (!Directory.Exists(folderPath)) { throw new ArgumentException($"Could not find folder '{folderPath}'"); }

            this.FolderPath = folderPath;
            this.FileSearchPattern = fileSearchPattern;
        }

        public override IEnumerable<string> GetPlaylistIds()
        {
            foreach (var file in this.GetFiles())
            {
                foreach (var id in File.ReadAllLines(file))
                {
                    yield return id;
                }

                this.MarkAsProcessed(file);
            }
        }

        private string[] GetFiles()
        {
            return Directory.GetFiles(this.FolderPath, this.FileSearchPattern);
        }

        private void MarkAsProcessed(string file)
        {
            string newFileName = $"PROCESSED_{Path.GetFileNameWithoutExtension(file)}{Path.GetExtension(file)}";
            File.Move(file, Path.Combine(Path.GetDirectoryName(file), newFileName));
        }
    }
}