pdf_or_html.js

var url, contentType;

casper.start(....)
//download time
//waitForResource because sometime the server is redirecting multiple time 
//the browser, so we need the final url to download it as pdf (or render it as html)
.waitForResource(function testResource(resource) {
  console.log("resource: "+resource.status+" : "+resource.contentType+" : "+resource.url);
  if(resource.status == 200) {
    url = resource.url;
    contentType = resource.contentType;
  }
  return resource.status == 200
},function onResourceReceived(resource){
  console.log("contentType: "+resource.contentType);
})
.then(function() {
  //we could also use the "contentType" to distinguish pdf to html
    if(url.indexOf(".pdf") > 0) {
        //there is a pdf to download
        console.log("downloading pdf: "+downloadPath+" - "+url);
        this.download(url,downloadPath);
    } else {
        //there is an html page to convert
        console.log("capturing html: "+downloadPath+" - "+url);
        this.capture(downloadPath);
    }
})