///
// Copyright (C) 2003, 2004, Fredrik Arnerup & Rasmus Kaj, See COPYING
///
#include <libxml++/libxml++.h>
#include <fstream>
#include <algorithm>

class XsltParamsFinder : public xmlpp::SaxParser {
public:
  XsltParamsFinder() : done(false) {}
  const std::vector<std::string>& result() const { return found; }

protected:
  void on_start_element(const std::string& n, 
			const xmlpp::SaxParser::AttributeList &p);

private:
  std::vector<std::string> found;
  std::string param_elem, template_elem;
  bool done;
};

void XsltParamsFinder::on_start_element
(const std::string& n, const xmlpp::SaxParser::AttributeList &p) 
{
  if(done) return;
  
  if(param_elem.empty()) {
    // This is the first element in the stylesheet, get the prefix from this
    // element!
    std::string::size_type p = n.find(':');
    if(p == std::string::npos) {
	param_elem = "param";
	template_elem = "template";
    } else {
      param_elem = n.substr(0, p) + ":param";
      template_elem = n.substr(0, p) + ":template";
    }
  } else if(n == param_elem) {
    using namespace xmlpp;
    const SaxParser::AttributeList::const_iterator i = 
      std::find_if(p.begin(), p.end(), SaxParser::AttributeHasName("name"));
    if(i != p.end()) {
      found.push_back(i->value);
    }
  } else if(n == template_elem) {
    /// \todo actually abort the parsing, rather than just converting the
    /// callback to a noop.
    done = true;
  }
}

std::vector<std::string> getXsltParams(const std::string& source) {
  XsltParamsFinder finder;
  std::ifstream in(source.c_str());
  finder.parse_stream(in);
  return finder.result();
}

#if 0
int main() {
  std::vector<std::string> params = get_params
    ("/home/kaj/proj/emission/emissionxml/passepartout/teaser.xslt");
  for(std::vector<std::string>::const_iterator i = params.begin();
      i != params.end(); ++i) {
    std::cout << "Found parameter: " << *i << std::endl;
  }
  return 0;
}
#endif