///
// Copyright (C) 2002 - 2004, Fredrik Arnerup & Rasmus Kaj, See COPYING
///
#include "clipboard.h"
#include <gtkmm/clipboard.h>
#include "document/page.h"
#include "document/textframe.h"
#include "document/loader.h"
#include "util/warning.h"

namespace {
  template<class P> P nonull(P p) {
    if(!p)
      throw std::runtime_error("A pointer was null in " __FILE__);
    return p;
  }
  
  std::string clip; // a global clip should suffice
  
  const std::string pptout_target = "PPTOUT_PAGENTS_2"; // with version number
  
  void on_clipboard_get(Gtk::SelectionData& selection_data, guint info) {
    const Glib::ustring& target = selection_data.get_target();
    if(target == pptout_target)
      selection_data.set(pptout_target, clip);
  }
  
  void on_clipboard_clear() {
    // not really necessary
    clip.clear();
  }
  
  void on_clipboard_received(const Gtk::SelectionData& selection_data,
                             std::pair<DocRef, Page*> bundle) {
    DocRef document = bundle.first;
    Page *page = bundle.second;
    Glib::ustring clipboard_data = selection_data.get_data_as_string();
    try {
      xmlpp::DomParser parser;
      parser.parse_memory(clipboard_data);
      xmlpp::Element *root = parser.get_document()->get_root_node();
      if(!root)
        throw std::runtime_error("Root node is NULL.");
      xmlpp::Element::NodeList children = root->get_children();
      
      document->select_all(false);
      for(xmlpp::Element::NodeList::const_iterator
            i = children.begin(); i != children.end(); i++) {
        if(xmlpp::Element *elem = dynamic_cast<xmlpp::Element*>(*i)) {
          if(elem->get_name() == "text_stream") {
            std::auto_ptr<TextStream> stream(new TextStream
                                             (ElementWrap("", *elem)));
            // Don't try to add a stream with a name that already exists
            /// \todo rename the stream automatically?
            if(!document->get_text_stream(stream->get_name()))
              document->add_text_stream(stream.release());
          } else {
            Pagent *pagent = load(ElementWrap("", *elem), page);
            page->add(pagent);
            document->select(pagent, false); // don't deselect
          }
        }
      }
    } catch(const std::exception& e) {
      throw std::runtime_error("Error encountered when pasting:\n"
                               + std::string(e.what()));
    }
  }
}

void Clipboard::copy(DocRef document) {
  nonull(document);
  
  /// \todo make sure the selection is sorted
  const Document::Selection selected = document->selected();
  if(selected.empty())
    return;
  
  Glib::RefPtr<Gtk::Clipboard> clipboard = Gtk::Clipboard::get();
  std::list<Gtk::TargetEntry> target_list;
  target_list.push_back(Gtk::TargetEntry(pptout_target));
  clipboard->set(target_list,
		 sigc::ptr_fun(&on_clipboard_get),
		 sigc::ptr_fun(&on_clipboard_clear));
  
  // store an XML representation of the selected pagents
  xmlpp::Document rep;
  xmlpp::Element *root = rep.create_root_node("copy_data");
  
  // save relevant streams
  typedef std::set<const TextStream*> Streams;
  Streams streams;
  for(Document::Selection::const_iterator i = selected.begin();
      i != selected.end(); i++) {
    const TextFrame *frame = dynamic_cast<const TextFrame *>(*i);
    if(!frame)
      continue;
    const TextStream *stream = frame->get_stream();
    if(stream && streams.find(stream) == streams.end()) {
      streams.insert(stream);
      stream->save(*root, FileContext());
    }
  }
  
  // save pagents
  for(Document::Selection::const_iterator i = selected.begin();
      i != selected.end(); i++) {
    (*i)->save(*root, FileContext());
  }
  
  clip = rep.write_to_string();
  debug << clip << std::endl;
}

void Clipboard::cut(DocRef document) {
  nonull(document);
  copy(document);
  document->delete_selected();
}

void Clipboard::paste(DocRef document, Page *page) {
  Gtk::Clipboard::get()->request_contents
    (pptout_target, sigc::bind(sigc::ptr_fun(&on_clipboard_received),
                               std::make_pair(nonull(document),
                                              nonull(page))));
}