Libation/Source/LibationUiBase/GridView/RowComparerBase.cs
Michael Bucari-Tovo bff9b67b72 Remove GridEntry derrived types and interfaces
Use existing BaseUtil.LoadImage delegate, obviating need for derrived classes to load images

Since GridEntry types are no longer generic, interfaces are unnecessary and deleted.
2025-07-21 10:47:10 -06:00

98 lines
3.0 KiB
C#

using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
#nullable enable
namespace LibationUiBase.GridView
{
/// <summary>
/// This compare class ensures that all top-level grid entries (standalone books or series parents)
/// are sorted by PropertyName while all episodes remain immediately beneath their parents and remain
/// sorted by series index, ascending.
/// </summary>
public abstract class RowComparerBase : IComparer, IComparer<GridEntry>, IComparer<object>
{
public abstract string? PropertyName { get; set; }
public int Compare(object? x, object? y)
=> Compare(x as GridEntry, y as GridEntry);
protected abstract ListSortDirection GetSortOrder();
private int InternalCompare(GridEntry x, GridEntry y)
{
var val1 = x.GetMemberValue(PropertyName);
var val2 = y.GetMemberValue(PropertyName);
var compare = x.GetMemberComparer(val1.GetType()).Compare(val1, val2);
return compare == 0 && x.Liberate.IsSeries && y.Liberate.IsSeries
//Both a and b are series parents and compare as equal, so break the tie.
? x.AudibleProductId.CompareTo(y.AudibleProductId)
: compare;
}
public int Compare(GridEntry? geA, GridEntry? geB)
{
if (geA is null && geB is not null) return -1;
if (geA is not null && geB is null) return 1;
if (geA is null || geB is null) return 0;
var sortDirection = GetSortOrder();
SeriesEntry? parentA = null;
SeriesEntry? parentB = null;
if (geA is LibraryBookEntry lbA && lbA.Parent is SeriesEntry seA)
parentA = seA;
if (geB is LibraryBookEntry lbB && lbB.Parent is SeriesEntry seB)
parentB = seB;
//both entries are children
if (parentA != null && parentB != null)
{
//both are children of the same series
if (parentA == parentB)
{
//Podcast episodes usually all have the same PurchaseDate and DateAdded property:
//the date that the series was added to the library. So when sorting by PurchaseDate
//and DateAdded, compare SeriesOrder instead..
return PropertyName switch
{
nameof(GridEntry.DateAdded) or nameof(GridEntry.PurchaseDate) => geA.SeriesOrder.CompareTo(geB.SeriesOrder),
_ => InternalCompare(geA, geB),
};
}
else
//a and b are children of different series.
return InternalCompare(parentA, parentB);
}
//a is top-level, b is a child
else if (parentA is null && parentB is not null)
{
// b is a child of a, parent is always first
if (parentB == geA)
return sortDirection is ListSortDirection.Ascending ? -1 : 1;
else
return InternalCompare(geA, parentB);
}
//a is a child, b is a top-level
else if (parentA is not null && parentB is null)
{
// a is a child of b, parent is always first
if (parentA == geB)
return sortDirection is ListSortDirection.Ascending ? 1 : -1;
else
return InternalCompare(parentA, geB);
}
//parentA and parentB are null
else
{
//both a and b are top-level grid entries
return InternalCompare(geA, geB);
}
}
}
}