using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using SatelliteProvider.Common.Configs;
using SatelliteProvider.DataAccess.Models;

namespace SatelliteProvider.Services.RouteManagement;

// AZ-364 / C11: extracted from RouteProcessingService.CleanupRegionFilesAsync.
// Deletes per-region files (CSV, summary, stitched image) once a route has
// successfully consumed them. Each delete is best-effort: a failed delete is
// logged at warning level and does not abort the cleanup of the remaining
// files. Stitched image path is reconstructed from regionId + ReadyDirectory
// because regions historically did not always persist that path on the entity.
public class RegionFileCleaner
{
    private readonly StorageConfig _storageConfig;
    private readonly ILogger<RegionFileCleaner> _logger;

    public RegionFileCleaner(IOptions<StorageConfig> storageConfig, ILogger<RegionFileCleaner> logger)
    {
        ArgumentNullException.ThrowIfNull(storageConfig);
        _storageConfig = storageConfig.Value;
        _logger = logger;
    }

    public Task CleanupAsync(IEnumerable<RegionEntity> regions, CancellationToken cancellationToken = default)
    {
        ArgumentNullException.ThrowIfNull(regions);

        foreach (var region in regions)
        {
            if (cancellationToken.IsCancellationRequested)
                break;

            if (region == null) continue;

            DeleteIfPresent(region.CsvFilePath, "region CSV file");
            DeleteIfPresent(region.SummaryFilePath, "region summary file");

            var stitchedImagePath = Path.Combine(_storageConfig.ReadyDirectory, $"region_{region.Id}_stitched.jpg");
            if (File.Exists(stitchedImagePath))
            {
                DeleteIfPresent(stitchedImagePath, "region stitched image");
            }
        }

        return Task.CompletedTask;
    }

    private void DeleteIfPresent(string? path, string label)
    {
        if (string.IsNullOrEmpty(path) || !File.Exists(path))
        {
            return;
        }

        try
        {
            File.Delete(path);
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "Failed to delete {Label}: {FilePath}", label, path);
        }
    }
}