using DocumentService.Application.Common.DTOs;
using DocumentService.Client.Interfaces;

namespace DocumentService.Client.Clients;

/// <summary>
/// Orchestrated multi-step workflows that compose multiple DocumentService clients
/// into single, higher-level operations.
/// </summary>
public class WorkflowsClient(IPdfValidationClient validation, ISwissQrCodeClient swissQrCode) : IWorkflowsClient
{
    /// <inheritdoc />
    public async Task<SwissQrCodeExtractionResult?> ExtractSwissQrCodeValidatedAsync(
        byte[] pdfBytes,
        bool raw = false,
        bool throwIfInvalid = true,
        CancellationToken cancellationToken = default)
    {
        var validationResult = await validation.ValidatePdfAsync(pdfBytes, cancellationToken);

        if (!validationResult.IsValid)
            return throwIfInvalid
                ? throw new InvalidOperationException(
                    $"PDF validation failed (IsEncrypted={validationResult.IsEncrypted}, " +
                    $"PageCount={validationResult.PageCount}, FileSize={validationResult.FileSizeBytes}).")
                : (SwissQrCodeExtractionResult?)null;

        return await swissQrCode.ExtractSwissQrCodeAsync(pdfBytes, raw, cancellationToken);
    }

    /// <inheritdoc />
    public async Task<SwissQrCodeExtractionResult?> ExtractSwissQrCodeValidatedAsync(
        Stream pdfStream,
        bool raw = false,
        bool throwIfInvalid = true,
        CancellationToken cancellationToken = default)
    {
        var validationResult = await validation.ValidatePdfAsync(pdfStream, cancellationToken);

        if (!validationResult.IsValid)
            return throwIfInvalid
                ? throw new InvalidOperationException(
                    $"PDF validation failed (IsEncrypted={validationResult.IsEncrypted}, " +
                    $"PageCount={validationResult.PageCount}, FileSize={validationResult.FileSizeBytes}).")
                : (SwissQrCodeExtractionResult?)null;

        // Stream was consumed by validation – reset if possible, otherwise re-open is caller's responsibility.
        // Since callers typically pass a FileStream or MemoryStream, Position reset covers the common case.
        if (pdfStream.CanSeek)
            pdfStream.Position = 0;

        return await swissQrCode.ExtractSwissQrCodeAsync(pdfStream, raw, cancellationToken);
    }

    /// <inheritdoc />
    public async Task<SwissQrCodeExtractionResult?> ExtractSwissQrCodeValidatedAsync(
        string filePath,
        bool raw = false,
        bool throwIfInvalid = true,
        CancellationToken cancellationToken = default)
    {
#if NETFRAMEWORK
        using var stream = File.OpenRead(filePath);
        var validationResult = await validation.ValidatePdfAsync(stream, cancellationToken);
#else
        var pdfBytes = await File.ReadAllBytesAsync(filePath, cancellationToken);
        var validationResult = await validation.ValidatePdfAsync(pdfBytes, cancellationToken);
#endif

        if (!validationResult.IsValid)
            return throwIfInvalid
                ? throw new InvalidOperationException(
                    $"PDF validation failed (IsEncrypted={validationResult.IsEncrypted}, " +
                    $"PageCount={validationResult.PageCount}, FileSize={validationResult.FileSizeBytes}).")
                : (SwissQrCodeExtractionResult?)null;

#if NETFRAMEWORK
        using var extractStream = File.OpenRead(filePath);
        return await swissQrCode.ExtractSwissQrCodeAsync(extractStream, raw, cancellationToken);
#else
        return await swissQrCode.ExtractSwissQrCodeAsync(pdfBytes, raw, cancellationToken);
#endif
    }
}