Refactoring

Controllers/Managers/ArtistManager.cs

@@ -1,6 +1,9 @@
 using System;
 using System.Collections.Generic;
 using System.Configuration;
+using System.Linq;
+
+using Microsoft.Extensions.Configuration;
 
 using Icarus.Controllers.Utilities;
 using Icarus.Models;
@@ -11,6 +14,7 @@ namespace Icarus.Controllers.Managers
     public class ArtistManager : BaseManager
     {
     	#region Fields
+		private ArtistContext _artistContext;
     	#endregion
 
 
@@ -19,10 +23,115 @@ namespace Icarus.Controllers.Managers
 
 
     	#region Constructors
+		public ArtistManager(IConfiguration config)
+		{
+			_config = config;
+			_connectionString = _config.GetConnectionString("DefaultConnection");
+			_artistContext = new ArtistContext(_connectionString);
+		}
     	#endregion
 
 
     	#region Methods
+        public void SaveArtistToDatabase(ref Song song)
+        {
+            _logger.Info("Starting process to save the artist record of the song to the database");
+
+            var artist = new Artist();
+
+            artist.Name = song.Artist;
+            artist.SongCount = 1;
+            var artistTitle = artist.Name;
+
+            var artistRetrieved = _artistContext.Artists.FirstOrDefault(art => art.Name.Equals(artistTitle));
+
+            if (artistRetrieved == null)
+            {
+                artist.SongCount = 1;
+                _artistContext.Add(artist);
+                _artistContext.SaveChanges();
+            }
+            else
+            {
+                artist.ArtistID = artistRetrieved.ArtistID;
+            }
+
+            song.ArtistID = artist.ArtistID;
+        }
+
+        public Artist UpdateArtistInDatabase(Song oldSongRecord, Song newSongRecord)
+        {
+            var oldArtistRecord = _artistContext.Artists.FirstOrDefault(art => art.Name.Equals(oldSongRecord.AlbumTitle));
+            var oldArtistName = oldArtistRecord.Name;
+            var newArtistName = newSongRecord.Artist;
+
+            if (string.IsNullOrEmpty(newArtistName) || oldArtistName.Equals(newArtistName))
+            {
+                _logger.Info("No change to the song's Artist");
+                return oldArtistRecord;
+            }
+
+            _logger.Info("Change to the song's record found");
+
+            if (oldArtistRecord.SongCount <= 1)
+            {
+                _logger.Info("Deleting artist record that no longer has any songs");
+
+                _artistContext.Remove(oldArtistRecord);
+                _artistContext.SaveChanges();
+            }
+
+            if (!(_artistContext.Artists.FirstOrDefault(art => art.Name.Equals(oldSongRecord.AlbumTitle)) != null))
+            {
+                _logger.Info("Creating new artist record");
+
+                var newArtistRecord = new Artist
+                {
+                    Name = newArtistName
+                };
+
+                _artistContext.Add(newArtistRecord);
+                _artistContext.SaveChanges();
+                
+                return newArtistRecord;
+            }
+            else
+            {
+                _logger.Info("Updating existing artist record");
+
+                var existingArtistRecord = _artistContext.Artists.FirstOrDefault(art => art.Name.Equals(newSongRecord.AlbumTitle));
+
+                _artistContext.Update(existingArtistRecord);
+                _artistContext.SaveChanges();
+
+                return existingArtistRecord;
+            }
+        }
+
+        public void DeleteArtistFromDatabase(Song song)
+        {
+            if (!(_artistContext.Artists.FirstOrDefault(art => art.Name.Equals(song.Artist)) != null))
+            {
+                _logger.Info("Cannot delete the artist record because it does not exist");
+                return;
+            }
+
+            var artist = _artistContext.Artists.FirstOrDefault(art => art.Name.Equals(song.Artist));
+
+            if (SongsOfArtist(artist) <= 1)
+            {
+                _artistContext.Remove(artist);
+                _artistContext.SaveChanges();
+            }
+        }
+
+		private int SongsOfArtist(Artist artist)
+		{
+			var sngContext = new SongContext(_connectionString);
+			var songs = sngContext.Songs.Where(sng => sng.ArtistID == artist.ArtistID).ToList();
+
+			return songs.Count;
+		}
     	#endregion
     }
 }