using Explorer.Application;
using Explorer.Domain;

namespace Explorer.Application.Tests;

public class FolderStatusTextTests
{
    [Fact]
    public void Empty_folder_is_zero_items()
    {
        Assert.Equal("0 items", FolderStatusText.Format([], []));
    }

    [Fact]
    public void Folder_totals_use_known_sizes()
    {
        var items = new[]
        {
            File("a.txt", 100),
            File("b.txt", 924),
            Folder("pics", size: 0, SizeKnowledge.Unknown)
        };

        Assert.Equal("3 items  ·  1 KB", FolderStatusText.Format(items, []));
    }

    [Fact]
    public void Selection_replaces_folder_totals()
    {
        var items = new[] { File("a.txt", 100), File("b.txt", 200), File("c.txt", 300) };

        Assert.Equal("1 item selected  ·  200 B", FolderStatusText.Format(items, [items[1]]));
        Assert.Equal("2 items selected  ·  300 B", FolderStatusText.Format(items, [items[0], items[1]]));
    }

    [Fact]
    public void Unknown_folder_sizes_are_omitted()
    {
        var folders = new[]
        {
            Folder("a", 0, SizeKnowledge.Unknown),
            Folder("b", 0, SizeKnowledge.Unknown)
        };

        Assert.Equal("2 items", FolderStatusText.Format(folders, []));
    }

    [Fact]
    public void Indexed_folder_sizes_are_included()
    {
        var items = new[]
        {
            Folder("docs", 2_048, SizeKnowledge.Calculated),
            File("readme.txt", 1_024)
        };

        Assert.Equal("2 items  ·  3 KB", FolderStatusText.Format(items, []));
    }

    [Fact]
    public void Zero_byte_file_selection_still_shows_size()
    {
        var file = File("empty.dat", 0);
        Assert.Equal("1 item selected  ·  0 B", FolderStatusText.Format([file], [file]));
    }

    private static FileSystemItem File(string name, long size)
        => new()
        {
            FullPath = @"C:\" + name,
            Name = name,
            SizeBytes = size,
            SizeKnowledge = SizeKnowledge.Calculated
        };

    private static FileSystemItem Folder(string name, long size, SizeKnowledge knowledge)
        => new()
        {
            FullPath = @"C:\" + name,
            Name = name,
            IsDirectory = true,
            SizeBytes = size,
            SizeKnowledge = knowledge
        };
}