aa/Shared/Models/FileHolder.cs

using System.Text.Json;
using System.Text.Json.Serialization;

namespace View_by_Distance.Shared.Models;

public record FileHolder(DateTime? CreationTime,
                         string? DirectoryFullPath,
                         bool Exists,
                         string ExtensionLowered,
                         string FullName,
                         int? Id,
                         DateTime? LastWriteTime,
                         long? Length,
                         string Name,
                         string NameWithoutExtension)
{

    public override string ToString()
    {
        string result = JsonSerializer.Serialize(this, FileHolderSourceGenerationContext.Default.FileHolder);
        return result;
    }

    private static FileHolder GetExisting(NginxFileSystem nginxFileSystem, int? id) =>
        new(CreationTime: nginxFileSystem.LastModified,
            DirectoryFullPath: Path.GetDirectoryName(nginxFileSystem.URI?.OriginalString ?? throw new Exception()),
            Exists: true,
            ExtensionLowered: Path.GetExtension(nginxFileSystem.Name).ToLower(),
            FullName: nginxFileSystem.URI?.OriginalString ?? throw new Exception(),
            Id: id,
            LastWriteTime: nginxFileSystem.LastModified,
            Length: nginxFileSystem.Length is null ? null : (long)nginxFileSystem.Length.Value,
            Name: nginxFileSystem.Name,
            NameWithoutExtension: Path.GetFileNameWithoutExtension(nginxFileSystem.Name));

    public static FileHolder Get(NginxFileSystem nginxFileSystem) =>
        GetExisting(nginxFileSystem, id: null);

    private static FileHolder GetExisting(FileInfo fileInfo, int? id) =>
        new(CreationTime: fileInfo.CreationTime,
            DirectoryFullPath: fileInfo.DirectoryName,
            Exists: fileInfo.Exists,
            ExtensionLowered: fileInfo.Extension.ToLower(),
            FullName: fileInfo.FullName,
            Id: id,
            LastWriteTime: fileInfo.LastWriteTime,
            Length: fileInfo.Length,
            Name: fileInfo.Name,
            NameWithoutExtension: Path.GetFileNameWithoutExtension(fileInfo.FullName));

    private static FileHolder GetNonExisting(FileInfo fileInfo, int? id) =>
        new(CreationTime: null,
            DirectoryFullPath: fileInfo.DirectoryName,
            Exists: fileInfo.Exists,
            ExtensionLowered: fileInfo.Extension.ToLower(),
            FullName: fileInfo.FullName,
            Id: id,
            LastWriteTime: null,
            Length: null,
            Name: fileInfo.Name,
            NameWithoutExtension: Path.GetFileNameWithoutExtension(fileInfo.FullName));

    public static FileHolder Get(FileInfo fileInfo, int? id) =>
        fileInfo.Exists ? GetExisting(fileInfo, id) : GetNonExisting(fileInfo, id);

    public static FileHolder Get(FilePath filePath, int? id)
    {
        FileHolder result;
        DateTime dateTime = new(filePath.CreationTicks);
        result = new(CreationTime: dateTime,
                     DirectoryFullPath: filePath.DirectoryFullPath,
                     Exists: true,
                     ExtensionLowered: filePath.ExtensionLowered,
                     FullName: filePath.FullName,
                     Id: id,
                     LastWriteTime: new(filePath.LastWriteTicks),
                     Length: filePath.Length,
                     Name: filePath.Name,
                     NameWithoutExtension: Path.GetFileNameWithoutExtension(filePath.FullName));
        return result;
    }

    private static FileHolder GetExisting(FileHolder fileHolder) =>
        new(CreationTime: fileHolder.CreationTime,
            DirectoryFullPath: fileHolder.DirectoryFullPath,
            Exists: fileHolder.Exists,
            ExtensionLowered: fileHolder.ExtensionLowered,
            FullName: fileHolder.FullName,
            Id: null,
            LastWriteTime: fileHolder.LastWriteTime,
            Length: fileHolder.Length,
            Name: fileHolder.Name,
            NameWithoutExtension: Path.GetFileNameWithoutExtension(fileHolder.FullName));

    private static FileHolder GetNonExisting(FileHolder fileHolder) =>
        new(CreationTime: null,
            DirectoryFullPath: fileHolder.DirectoryFullPath,
            Exists: fileHolder.Exists,
            ExtensionLowered: fileHolder.ExtensionLowered,
            FullName: fileHolder.FullName,
            Id: null,
            LastWriteTime: null,
            Length: null,
            Name: fileHolder.Name,
            NameWithoutExtension: Path.GetFileNameWithoutExtension(fileHolder.FullName));

    public static FileHolder Get(FileHolder fileHolder) =>
        fileHolder.Exists ? GetExisting(fileHolder) : GetNonExisting(fileHolder);

    public static FileHolder Get(string file) =>
        Get(new FileInfo(file), id: null);

}

[JsonSourceGenerationOptions(WriteIndented = true)]
[JsonSerializable(typeof(FileHolder))]
internal partial class FileHolderSourceGenerationContext : JsonSerializerContext
{
}