public async Task <PreviewResult> Preview(PrintingPreviewTemplate template, PrintArguments args, CancellationToken cancellation)
{
await Initialize(cancellation);
var parameters = template.Parameters?.Select(e => new AbstractParameter(e.Key, e.Control));
var abstractTemplate = new AbstractPrintingTemplate(template.Body, template.DownloadName, template.Context, parameters);
var(body, downloadName) = await PrintImpl(abstractTemplate, args, cancellation);
return(new PreviewResult(body, downloadName));
}
private async Task <(string body, string fileName)> PrintImpl(AbstractPrintingTemplate template, PrintArguments args, CancellationToken cancellation)
{
// (1) The templates
var nameP = new TemplatePlanLeaf(template.DownloadName, TemplateLanguage.Text);
var bodyP = new TemplatePlanLeaf(template.Body, TemplateLanguage.Html);
TemplatePlan plan = new TemplatePlanTuple(nameP, bodyP);
if (!string.IsNullOrWhiteSpace(template.Context))
{
plan = new TemplatePlanDefine("$", template.Context, plan);
}
// (2) Functions + Variables
var globalFunctions = new Dictionary <string, EvaluationFunction>();
var localFunctions = new Dictionary <string, EvaluationFunction>();
var globalVariables = new Dictionary <string, EvaluationVariable>();
var localVariables = BaseUtil.CustomLocalVariables(args, template.Parameters?.Select(e => e.Key));
await FactBehavior.SetPrintingFunctions(localFunctions, globalFunctions, cancellation);
await FactBehavior.SetPrintingVariables(localVariables, globalVariables, cancellation);
// (3) Generate output
CultureInfo culture = GetCulture(args.Culture);
var genArgs = new TemplateArguments(globalFunctions, globalVariables, localFunctions, localVariables, culture: culture);
await _templateService.GenerateFromPlan(plan : plan, args : genArgs, cancellation : cancellation);
var downloadName = nameP.Outputs[0];
var body = bodyP.Outputs[0];
// Use a default download name if none is provided
if (string.IsNullOrWhiteSpace(downloadName))
{
downloadName = "File.html";
}
if (!downloadName.ToLower().EndsWith(".html"))
{
downloadName += ".html";
}
// Return as a file
return(new(body, downloadName));
}