Pushing missing changes

MediaBrowser.UI/ViewModels/DtoBaseItemViewModel.cs

@@ -0,0 +1,184 @@
+using MediaBrowser.Common.Logging;
+using MediaBrowser.Model.DTO;
+using MediaBrowser.Model.Entities;
+using MediaBrowser.UI.Pages;
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+
+namespace MediaBrowser.UI.ViewModels
+{
+    /// <summary>
+    /// Class DtoBaseItemViewModel
+    /// </summary>
+    public class DtoBaseItemViewModel : BaseViewModel
+    {
+        /// <summary>
+        /// The _average primary image aspect ratio
+        /// </summary>
+        private double _averagePrimaryImageAspectRatio;
+        /// <summary>
+        /// Gets the aspect ratio that should be used if displaying the primary image
+        /// </summary>
+        /// <value>The average primary image aspect ratio.</value>
+        public double AveragePrimaryImageAspectRatio
+        {
+            get { return _averagePrimaryImageAspectRatio; }
+
+            set
+            {
+                _averagePrimaryImageAspectRatio = value;
+                OnPropertyChanged("AveragePrimaryImageAspectRatio");
+            }
+        }
+
+        /// <summary>
+        /// The _parent display preferences
+        /// </summary>
+        private DisplayPreferences _parentDisplayPreferences;
+        /// <summary>
+        /// Gets of sets the current DisplayPreferences
+        /// </summary>
+        /// <value>The parent display preferences.</value>
+        public DisplayPreferences ParentDisplayPreferences
+        {
+            get { return _parentDisplayPreferences; }
+
+            set
+            {
+                _parentDisplayPreferences = value;
+                NotifyDisplayPreferencesChanged();
+            }
+        }
+
+        /// <summary>
+        /// The _item
+        /// </summary>
+        private DtoBaseItem _item;
+        /// <summary>
+        /// Gets or sets the item.
+        /// </summary>
+        /// <value>The item.</value>
+        public DtoBaseItem Item
+        {
+            get { return _item; }
+
+            set
+            {
+                _item = value;
+                OnPropertyChanged("Item");
+            }
+        }
+
+        /// <summary>
+        /// Notifies the display preferences changed.
+        /// </summary>
+        public void NotifyDisplayPreferencesChanged()
+        {
+            OnPropertyChanged("DisplayPreferences");
+        }
+
+        /// <summary>
+        /// Gets an image url that can be used to download an image from the api
+        /// </summary>
+        /// <param name="imageType">The type of image requested</param>
+        /// <param name="imageIndex">The image index, if there are multiple. Currently only applies to backdrops. Supply null or 0 for first backdrop.</param>
+        /// <returns>System.String.</returns>
+        public string GetImageUrl(ImageType imageType, int? imageIndex = null)
+        {
+            var height = ParentDisplayPreferences.PrimaryImageHeight;
+
+            var averageAspectRatio = BaseFolderPage.GetAspectRatio(imageType, AveragePrimaryImageAspectRatio);
+
+            var width = height * averageAspectRatio;
+
+            var imageOptions = new ImageOptions
+            {
+                ImageType = imageType,
+                ImageIndex = imageIndex,
+                Height = height
+            };
+
+            if (imageType == ImageType.Primary)
+            {
+                var currentAspectRatio = imageType == ImageType.Primary ? Item.PrimaryImageAspectRatio ?? width / height : width / height;
+
+                // Preserve the exact AR if it deviates from the average significantly
+                var preserveExactAspectRatio = Math.Abs(currentAspectRatio - averageAspectRatio) > .10;
+
+                if (!preserveExactAspectRatio)
+                {
+                    imageOptions.Width = Convert.ToInt32(width);
+                }
+            }
+
+            return App.Instance.ApiClient.GetImageUrl(Item, imageOptions);
+        }
+
+        /// <summary>
+        /// Gets the average primary image aspect ratio.
+        /// </summary>
+        /// <param name="items">The items.</param>
+        /// <returns>System.Double.</returns>
+        /// <exception cref="System.ArgumentNullException">items</exception>
+        public static double GetAveragePrimaryImageAspectRatio(IEnumerable<DtoBaseItem> items)
+        {
+            if (items == null)
+            {
+                throw new ArgumentNullException("items");
+            }
+
+            double total = 0;
+            var count = 0;
+
+            foreach (var child in items)
+            {
+                var ratio = child.PrimaryImageAspectRatio ?? 0;
+
+                if (ratio.Equals(0))
+                {
+                    continue;
+                }
+
+                total += ratio;
+                count++;
+            }
+
+            return count == 0 ? 1 : total / count;
+        }
+
+        /// <summary>
+        /// Gets the observable items.
+        /// </summary>
+        /// <param name="items">The items.</param>
+        /// <returns>ObservableCollection{DtoBaseItemViewModel}.</returns>
+        public static ObservableCollection<DtoBaseItemViewModel> GetObservableItems(DtoBaseItem[] items)
+        {
+            return GetObservableItems(items, GetAveragePrimaryImageAspectRatio(items));
+        }
+        
+        /// <summary>
+        /// Gets the observable items.
+        /// </summary>
+        /// <param name="items">The items.</param>
+        /// <param name="averagePrimaryImageAspectRatio">The average primary image aspect ratio.</param>
+        /// <param name="parentDisplayPreferences">The parent display preferences.</param>
+        /// <returns>ObservableCollection{DtoBaseItemViewModel}.</returns>
+        /// <exception cref="System.ArgumentNullException">items</exception>
+        public static ObservableCollection<DtoBaseItemViewModel> GetObservableItems(IEnumerable<DtoBaseItem> items, double averagePrimaryImageAspectRatio, DisplayPreferences parentDisplayPreferences = null)
+        {
+            if (items == null)
+            {
+                throw new ArgumentNullException("items");
+            }
+
+            return new ObservableCollection<DtoBaseItemViewModel>(items.Select(i => new DtoBaseItemViewModel
+            {
+                Item = i,
+                ParentDisplayPreferences = parentDisplayPreferences,
+                AveragePrimaryImageAspectRatio = averagePrimaryImageAspectRatio
+            }));
+        }
+    }
+}