/// <summary>
/// Apply instructions to an image.
/// A good point to extra configuration of Image Resizer
/// </summary>
/// <param name="inputStream">Input image stream</param>
/// <param name="outputStream">Output stream to write the result</param>
/// <param name="instructions">Instructions to apply</param>
/// <returns>Result image as a stream. Caller have to care about the stream disposing.</returns>
protected virtual ImageProcessingResult ProcessImage(Stream inputStream, Stream outputStream, Instructions instructions)
{
if (!inputStream.CanRead)
{
throw new ArgumentException("inputStream is nor readable");
}
if (!outputStream.CanWrite)
{
throw new ArgumentException("outputStream is nor writable");
}
var job = ImageBuilder.Current.Build(inputStream, outputStream, instructions);
var res = new ImageProcessingResult();
if (!string.IsNullOrEmpty(job.ResultFileExtension))
{
res.FileExt = job.ResultFileExtension;
}
if (!string.IsNullOrEmpty(job.ResultMimeType))
{
res.MediaType = job.ResultMimeType;
}
return(res);
}
/// <summary>
/// Build file info object based on existing info & processing result. The result represents stored file but not the original one.
/// For example if the original was a jpeg image, but after processing it's converted into png, file ext & mime type will be updated.
/// </summary>
/// <param name="fileInfo">Income file info</param>
/// <param name="processingResult">Stored file info</param>
/// <returns></returns>
protected virtual IFileInfo BuildFileInfo(IFileInfo fileInfo, ImageProcessingResult processingResult)
{
var res = new IncomeFileInfo(fileInfo)
{
MimeType = processingResult.MediaType
};
if (processingResult.FileExt != null && !res.OriginalName.EndsWith(processingResult.FileExt, StringComparison.OrdinalIgnoreCase))
{
// Need to correct file ext
var dotIndex = res.OriginalName.LastIndexOf('.');
if (dotIndex > 0)
{
res.OriginalName = res.OriginalName.Substring(0, dotIndex);
}
res.OriginalName += '.' + processingResult.FileExt;
}
return(res);
}
