using DocumentOperator.Application.Common.Interfaces;
using DocumentOperator.Domain.Models.ValueObjects;
using MediatR;

namespace DocumentOperator.Application.Features.Documents.ValidatePdf;

/// <summary>
/// Handler for ValidatePdfQuery
/// Orchestrates PDF validation using IPdfProcessor
/// </summary>
public class ValidatePdfHandler : IRequestHandler<ValidatePdfQuery, PdfMetadata>
{
    private readonly IPdfProcessor _pdfProcessor;

    public ValidatePdfHandler(IPdfProcessor pdfProcessor)
    {
        _pdfProcessor = pdfProcessor;
    }

    /// <summary>
    /// Validates PDF and returns metadata
    /// </summary>
    public async Task<PdfMetadata> Handle(ValidatePdfQuery request, CancellationToken cancellationToken)
    {
        // Value Object ? Byte Array
        byte[] pdfBytes = request.PdfContent.ToByteArray();

        // DevExpress Service aufrufen (kann PdfProcessingException werfen)
        var metadata = await _pdfProcessor.ValidateAsync(pdfBytes);

        return metadata;
    }
}