* Batch actions for visible books: 'remove from library' complete

* refactor entity properties into extension methods
* refactor shared simple message boxes => MessageBoxLib

Source/DataLayer/EntityExtensions.cs

@@ -0,0 +1,102 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace DataLayer
+{
+    public static class EntityExtensions
+    {
+        public static string TitleSortable(this Book book) => Formatters.GetSortName(book.Title);
+
+        public static string AuthorNames(this Book book) => string.Join(", ", book.Authors.Select(a => a.Name));
+        public static string NarratorNames(this Book book) => string.Join(", ", book.Narrators.Select(n => n.Name));
+
+        /// <summary>True if IsLiberated or Error. False if NotLiberated</summary>
+        public static bool Audio_Exists(this Book book) => book.UserDefinedItem.BookStatus != LiberatedStatus.NotLiberated;
+        /// <summary>True if exists and IsLiberated. Else false</summary>
+        public static bool PDF_Exists(this Book book) => book.UserDefinedItem.PdfStatus == LiberatedStatus.Liberated;
+
+        public static string SeriesSortable(this Book book) => Formatters.GetSortName(book.SeriesNames());
+		public static bool HasPdf(this Book book) => book.Supplements.Any();
+        public static string SeriesNames(this Book book)
+        {
+            if (book.SeriesLink is null)
+                return "";
+
+            // first: alphabetical by name
+            var withNames = book.SeriesLink
+                .Where(s => !string.IsNullOrWhiteSpace(s.Series.Name))
+                .Select(s => s.Series.Name)
+                .OrderBy(a => a)
+                .ToList();
+            // then un-named are alpha by series id
+            var nullNames = book.SeriesLink
+                .Where(s => string.IsNullOrWhiteSpace(s.Series.Name))
+                .Select(s => s.Series.AudibleSeriesId)
+                .OrderBy(a => a)
+                .ToList();
+
+            var all = withNames.Union(nullNames).ToList();
+            return string.Join(", ", all);
+        }
+        public static string[] CategoriesNames(this Book book)
+            => book.Category is null ? new string[0]
+            : book.Category.ParentCategory is null ? new[] { book.Category.Name }
+            : new[] { book.Category.ParentCategory.Name, book.Category.Name };
+        public static string[] CategoriesIds(this Book book)
+            => book.Category is null ? null
+            : book.Category.ParentCategory is null ? new[] { book.Category.AudibleCategoryId }
+            : new[] { book.Category.ParentCategory.AudibleCategoryId, book.Category.AudibleCategoryId };
+
+        public static string AggregateTitles(this IEnumerable<LibraryBook> libraryBooks, int max = 5)
+		{
+			if (libraryBooks is null || !libraryBooks.Any())
+				return "";
+
+			max = Math.Max(max, 1);
+
+			var titles = libraryBooks.Select(lb => "- " + lb.Book.Title).ToList();
+			var titlesAgg = titles.Take(max).Aggregate((a, b) => $"{a}\r\n{b}");
+			if (titles.Count == max + 1)
+				titlesAgg += $"\r\n\r\nand 1 other";
+			else if (titles.Count > max + 1)
+				titlesAgg += $"\r\n\r\nand {titles.Count - max } others";
+			return titlesAgg;
+		}
+
+        public static float FirstScore(this Rating rating)
+            => rating.OverallRating > 0 ? rating.OverallRating
+            : rating.PerformanceRating > 0 ? rating.PerformanceRating
+            : rating.StoryRating;
+        public static string ToStarString(this Rating rating)
+        {
+            var items = new List<string>();
+
+            if (rating.OverallRating > 0)
+                items.Add($"Overall:   {getStars(rating.OverallRating)}");
+            if (rating.PerformanceRating > 0)
+                items.Add($"Perform: {getStars(rating.PerformanceRating)}");
+            if (rating.StoryRating > 0)
+                items.Add($"Story:      {getStars(rating.StoryRating)}");
+
+            return string.Join("\r\n", items);
+        }
+        /// <summary>character: ★</summary>
+        const char STAR = '\u2605';
+        /// <summary>character: ½</summary>
+        const char HALF = '\u00BD';
+        private static string getStars(float score)
+        {
+            var fullStars = (int)Math.Floor(score);
+
+            var starString = new string(STAR, fullStars);
+
+            if (score - fullStars >= 0.25f)
+                starString += HALF;
+
+            return starString;
+        }
+    }
+}