--------------



void Song::process_crop(JmbMessage* m, bool type)
	{
	if (m->beginHold)
		{
		MustuxAction* a = new MustuxCropAction(this,m);
		return a;
		}
	else
		{
		MustuxAction* a = MHE->current();
		a->do();
		return (MustuxAction*) 0; // this is to avoid another PUSH ! MHE must be prepared to ignore pushing zeros...
		}
	PEXIT;
	}





class MustuxCropAction : public MustuxAction
	{
	public :
		MustuxCropAction(Song* mySong, JmbMessage* m)
			: MustuxAction(m)
			{
			this->mySong = mySong;
			this->origBlockL = mySong->xpos_to_block(mySong->clip_area_mouse_x(jmbMessage->mousex()));
			this->origBlockR = -1;
			mySong->update_last_block();
			QPtrList<AudioClip*> originalCliplist = new QPtrList<AudioClip*>()
			QPtrList<AudioClip*> clipToDeletelist = new QPtrList<AudioClip*>()

			}

		void do_action()
			{
			this->origBlockR = mySong->xpos_to_block(mySong->clip_area_mouse_x(jmbMessage->mousex()));

			// save the original clipsclips
			for (int t =0; t<mySong->numTracks; t++)
				{
				AudioClip* cli1 = mySong->track[t]->get_clip_under(origBlockL);
				AudioClip* cli2 = mySong->track[t]->get_clip_under(origBlockR);
				originalCliplist->add(cli1);
				originalCliplist->add(cli1);
				}


			PMESG2("Splitting clips at %ld and %ld",(long)origBlockL,(long)origBlockR);
			for (int t =0; t<mySong->numTracks; t++)
				{
				// ClipPair is a auxiliary class returned by split so you have pointer to the two remaining clips after split. in this example, I assume it exists, but must still be implemented...
				ClipPair* cpLeft = mySong->track[t]->split_clip(origBlockL);
				ClipPair* cpRight = mySong->track[t]->split_clip(origBlockR);
				// save them for deletion in case of undo
				clipToDeleteList->add(cpLeft->clipAtLeft);
				clipToDeleteList->add(cpLeft->clipAtRight);
				clipToDeleteList->add(cpRight->clipAtLeft);
				clipToDeleteList->add(cpRight->clipAtRight);
				}
			long long hb = (origBlockL+origBlockR)/2;
			PMESG2("Deleting all clips in the half point (%ld)",(long)hb);
			for (int t =0; t<mySong->numTracks; t++)
				{
				AudioClip* cli = mySong->track[t]->get_clip_under(hb);
				if (cli) mySong->track[t]->delete_clip(cli); // thats why I need it !
				}
			long long mb = origBlockR - origBlockL;
			PMESG2("Moving all clips beyond %ld and moving left in %ld blocks\n",(long)origBlockL,(long)mb);
			for (int t =0; t<mySong->numTracks; t++)
				{
				AudioClip* cli = mySong->track[t]->get_clip_after(origBlockL);
				while (cli)
					{
					long long tfb = cli->trackFirstBlock;
					cli->set_track_first_block(tfb - mb);
					cli=cli->next;
					}
				}
			mySong->mta->recreate();
			mySong->update_last_block();
			}


		void undo_action()
			{
			// delete the created clips
			QPtrListITerator it(clipToDeleteList);
				{
				for ( it; it.hasNext(); ++it)
					{
					AudioClip* c= it.get();
					delete c;
					}
				}
			// RESTORE THE ORIGINAL CLIPS
			QPtrListITerator it(originalClipList);
				{
				for ( it; it.hasNext(); ++it)
					{
					AudioClip* c= it.get();
					c->reparent(); // that method does not exist. must be implemented. it just ask the parent track to re-add it.
					}
				}

			}

	}