public IDocument ConvertPDF(IDocument document, IPdfConversionOptions options)
{
// check qpdf location is valid
if (!File.Exists(_options.InstallDirectory))
{
throw new Exception("Could not find a valid version of QPDF!");
}
// check that the file we are working with is valid
if (!File.Exists(document.Fullpath))
{
throw new Exception("Source document could not be found!");
}
// get the arguments for the QPDF executable
var outputDocument = new QPdfDocument(document.Filename);
var arguments = GetQPdfArguments(options, document, outputDocument);
// execute QPDF
using var process = new Process();
process.StartInfo.FileName = _options.InstallDirectory;
process.StartInfo.Arguments = arguments;
process.StartInfo.UseShellExecute = false;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.RedirectStandardInput = true;
using var outputWaitHandler = new AutoResetEvent(false);
using var errorWaitHandler = new AutoResetEvent(false);
var output = new StringBuilder();
DataReceivedEventHandler outputHandler = (sender, e) => {
if (e.Data == null)
{
outputWaitHandler.Set();
}
else
{
output.AppendLine(e.Data);
}
};
var error = new StringBuilder();
DataReceivedEventHandler errorHandler = (sender, e) => {
if (e.Data == null)
{
errorWaitHandler.Set();
}
else
{
error.AppendLine(e.Data);
}
};
process.OutputDataReceived += outputHandler;
process.ErrorDataReceived += errorHandler;
try {
process.Start();
process.BeginOutputReadLine();
process.BeginErrorReadLine();
if (process.WaitForExit(options.Timeout) && outputWaitHandler.WaitOne(options.Timeout) && errorWaitHandler.WaitOne(options.Timeout))
{
if (process.ExitCode != 0 || !File.Exists(outputDocument.Fullpath))
{
throw new Exception("QPDF failed to convert!");
}
}
else
{
if (!process.HasExited)
{
process.Kill();
}
throw new Exception("QPDF has timed out!");
}
}
finally {
process.OutputDataReceived -= outputHandler;
process.ErrorDataReceived -= errorHandler;
}
// handle the return value
outputDocument.SetData(File.ReadAllBytes(outputDocument.Fullpath));
return(outputDocument);
}
private string GetQPdfArguments(IPdfConversionOptions options, IDocument from, IDocument to)
{
var paramsBuilder = new StringBuilder();
// check for a password
if (!string.IsNullOrWhiteSpace(from.Password))
{
paramsBuilder.Append($"--password={from.Password} ");
}
// handle encryption options
if (options.Encryption == EncryptionOptions.decrypt)
{
paramsBuilder.Append("--decrypt ");
}
else if (options.Encryption == EncryptionOptions.encrypt)
{
// check for valid encryption password
if (string.IsNullOrWhiteSpace(options.MasterPassword))
{
throw new Exception("Master Password has to be set for encryption to take place!");
}
paramsBuilder.Append($"--encrypt {options.MasterPassword} {options.MasterPassword} {options.EncryptionKeyLength} ");
paramsBuilder.AppendFormat("--accessibility={0} ", options.Accessibility ? "y" : "n");
paramsBuilder.AppendFormat("--extract={0} ", options.TextGraphicExtraction ? "y" : "n");
string printOption = string.Empty;
switch (options.Printing)
{
case PrintOptions.full:
printOption = "full";
break;
case PrintOptions.low:
printOption = "low";
break;
case PrintOptions.disallow:
printOption = "none";
break;
}
if (!string.IsNullOrWhiteSpace(printOption))
{
paramsBuilder.AppendFormat("--print={0} ", printOption);
}
string modifyOption = string.Empty;
switch (options.EncryptionModification)
{
case EncryptionModification.all:
modifyOption = "all";
break;
case EncryptionModification.annotate:
modifyOption = "annotate";
break;
case EncryptionModification.form:
modifyOption = "form";
break;
case EncryptionModification.assembly:
modifyOption = "assembly";
break;
case EncryptionModification.none:
modifyOption = "none";
break;
}
if (!string.IsNullOrWhiteSpace(modifyOption))
{
paramsBuilder.AppendFormat("--modify={0} ", modifyOption);
}
paramsBuilder.Append("-- ");
}
// handle paging
if (options.Paging == PagingOptions.all)
{
paramsBuilder.AppendFormat("\"{0}\" \"{1}\"", from.Fullpath, to.Fullpath);
}
else
{
paramsBuilder.AppendFormat("\"{0}\" --pages \"{0}\" {1}-{2} -- \"{3}\"", from.Fullpath, options.PageStart, options.PageEnd, to.Fullpath);
}
return(paramsBuilder.ToString());
}