@Override
	public Line getNextFromTextIntro() {
		if (this.getIndex() < ((TextIntroImp) this.getParent()).getLineNb() - 1) {
			return ((TextIntroImp) this.getParent())
					.getLine(this.getIndex() + 1);
		} else {
			if (((TextIntroImp) this.getParent()).getParent() instanceof DocumentImp) {
				Document doc = ((Document) ((TextIntroImp) this.getParent())
						.getParent());
				if(doc.getSubSectionNb() > 0)
					return doc.getSubSection(0).getTitle().getLine();
				else return doc.getTextIntro().getLastLine();
				
			} else if (((SectionImp) ((TextIntroImp) this.getParent())
					.getParent()).getNextSection() != null) {
				return ((SectionImp) ((TextIntroImp) this.getParent())
						.getParent()).getNextSection().getFirstLine();
			} else {
				return this;
			}
		}

	}