using Microsoft.Extensions.Logging;

namespace GSS2.Core.Hardware;

public class ImageStorageService
{
    private readonly ILogger<ImageStorageService> _logger;
    private readonly DirectoryInfo _rootDirectory;

    public ImageStorageService(ILogger<ImageStorageService> logger, DirectoryInfo rootDirectory)
    {
        _logger = logger;
        _logger.LogInformation("Initialization");

        _rootDirectory = rootDirectory;
        if (!_rootDirectory.Exists)
        {
            _rootDirectory.Create();
            _logger.LogInformation("Created directory: {}", _rootDirectory.FullName);
        }

        _logger.LogInformation("Initialized");
    }

    public async Task<string> SaveAsync(Stream fileStream, string extension, CancellationToken ct = default)
    {
        var fileName = GenerateFileName(extension);
        var fullPath = GetFullPath(fileName);

        var directory = Path.GetDirectoryName(fullPath)!;
        Directory.CreateDirectory(directory);

        await using var file = new FileStream(
            fullPath,
            FileMode.CreateNew,
            FileAccess.Write,
            FileShare.None,
            81920,
            useAsync: true);

        await fileStream.CopyToAsync(file, ct);

        _logger.LogInformation("File saved: {FileName}", fileName);

        return fileName;
    }

    public Stream OpenRead(string fileName)
    {
        var fullPath = GetFullPath(fileName);
        return new FileStream(fullPath, FileMode.Open, FileAccess.Read, FileShare.Read);
    }

    public bool Delete(string fileName)
    {
        var fullPath = GetFullPath(fileName);

        if (!File.Exists(fullPath))
            return false;

        File.Delete(fullPath);
        return true;
    }

    private string GenerateFileName(string extension)
    {
        var guid = Guid.NewGuid().ToString("N");
        return $"{guid}{extension}";
    }

    public string GetFullPath(string fileName)
    {
        var level1 = fileName.Substring(0, 2);
        var level2 = fileName.Substring(2, 2);

        return Path.Combine(_rootDirectory.FullName, level1, level2, fileName);
    }
}