PDFa WriteDefines

[iMoppel]

Is your feature request related to a problem? Please describe

I cannot use the pdfwritedefines for PDFa

Describe the solution you'd like

Make the Format property of the PDFWriteDefines settable or create a PDFa WriteDefines what is a copy of the current PDFWriteDefines with an other Format behind the FormatField:

public sealed class PdfaWriteDefines : IWriteDefines
{
///

/// Gets or sets the author of the pdf document (pdf:author).
///

public string? Author { get; set; }

/// <summary>
/// Gets or sets the creation time of the pdf document (pdf:create-epoch).
/// </summary>
public DateTime? CreationTime { get; set; }

/// <summary>
/// Gets or sets the creator of the pdf document (pdf:creator).
/// </summary>
public string? Creator { get; set; }

/// <summary>
/// Gets the format where the defines are for.
/// </summary>
public MagickFormat Format
    => MagickFormat.Pdfa;

/// <summary>
/// Gets or sets the keywords of the pdf document (pdf:keywords).
/// </summary>
public string? Keywords { get; set; }

/// <summary>
/// Gets or sets the modification time of the pdf document (pdf:modify-epoch).
/// </summary>
public DateTime? ModificationTime { get; set; }

/// <summary>
/// Gets or sets a value indicating whether an identifier should be written (pdf:no-identifier).
/// </summary>
public bool? NoIdentifier { get; set; }

/// <summary>
/// Gets or sets the producer of the pdf document (pdf:producer).
/// </summary>
public string? Producer { get; set; }

/// <summary>
/// Gets or sets the subject of the pdf document (pdf:subject).
/// </summary>
public string? Subject { get; set; }

/// <summary>
/// Gets or sets a value indicating whether a thumbnail should be added to the pdf document (pdf:thumbnail).
/// </summary>
public bool? Thumbnail { get; set; }

/// <summary>
/// Gets or sets the title of the pdf document (pdf:title).
/// </summary>
public string? Title { get; set; }

/// <summary>
/// Gets or sets the version of the pdf document, for example 1.4 or 1.7 (pdf:version).
/// </summary>
public double? Version { get; set; }

/// <summary>
/// Gets the defines that should be set as a define on an image.
/// </summary>
public IEnumerable<IDefine> Defines
{
    get
    {
        if (Author?.Length > 0)
            yield return new MagickDefine(Format, "author", Author);

        if (CreationTime is not null)
            yield return new MagickDefine(Format, "create-epoch", ToUnixTimeSeconds(CreationTime.Value));

        if (Creator?.Length > 0)
            yield return new MagickDefine(Format, "creator", Creator);

        if (Keywords?.Length > 0)
            yield return new MagickDefine(Format, "keywords", Keywords);

        if (ModificationTime is not null)
            yield return new MagickDefine(Format, "modify-epoch", ToUnixTimeSeconds(ModificationTime.Value));

        if (NoIdentifier == true)
            yield return new MagickDefine(Format, "no-identifier", NoIdentifier.Value);

        if (Producer?.Length > 0)
            yield return new MagickDefine(Format, "producer", Producer);

        if (Subject?.Length > 0)
            yield return new MagickDefine(Format, "subject", Subject);

        if (Thumbnail.HasValue)
            yield return new MagickDefine(Format, "thumbnail", Thumbnail.Value);

        if (Version.HasValue)
            yield return new MagickDefine(Format, "version", Version.Value.ToString(".0", CultureInfo.InvariantCulture));

        if (Title?.Length > 0)
            yield return new MagickDefine(Format, "title", Title);
    }
}

private static long ToUnixTimeSeconds(DateTime value)
{
    var dateTimeOffset = (DateTimeOffset)value.ToUniversalTime();
    return dateTimeOffset.ToUnixTimeSeconds();
}

}

Describe alternatives you've considered

No response

Additional context

No response

[dlemstra]

Thanks for reporting this. I will need to think about how I would want to solve this.

[dlemstra]

After the next release you will be able to do new PdfWriteDefines(MagickFormat.Pdfa) to specify that you want to use MagickFormat.Pdfa as the output format.