function navigate(section) {
	document.main_form.navigation.value = section;

	if (document.main_form.main_id != null)
		document.main_form.main_id.value = "";

	if (document.main_form.book_id != null)
		document.main_form.book_id.value = "";

	if (document.main_form.show_text_id != null)
		document.main_form.show_text_id.value = "";

	if (document.main_form.start != null)
		document.main_form.start.value = "";

	document.main_form.submit();
}

function changeLanguage(language) {
	document.main_form.languageSwitch.value = language;

	if (language == 'lat') { // ajutiselt viib läti link otse jõulukaartidesse ruts tellis 23.11.2006
		show_book_list('book_list', 14, 19);
	}
	document.main_form.submit();
}

function show_book_list(navigation, mid, sid) {

	document.main_form.navigation.value = navigation;

	if (mid != 'search') {
		document.main_form.book_search_description.value = "";
		document.main_form.book_search_select.value = "";
	}

	document.main_form.mid.value = mid;
	document.main_form.sid.value = sid;

	document.main_form.sort_by.value = '';

	if (document.main_form.start != null)
		document.main_form.start.value = "";

	document.main_form.submit();
}

function show_book(navigation, id) {
	document.main_form.navigation.value = navigation;
	document.main_form.book_id.value = id;
	document.main_form.submit();
}

function show_book_in_language(navigation, id, language) {

	document.main_form.navigation.value = navigation;
	document.main_form.book_id.value = id;
	document.main_form.book_language.value = language;
	document.main_form.submit();
}

function show_picture(navigation, id) {
	document.main_form.navigation.value = navigation;
	document.main_form.show_picture_id.value = id;
	document.main_form.submit();
}

function sort_book_list(sort_by) {
	document.main_form.navigation.value = 'book_list';
	document.main_form.sort_by.value = sort_by;
	document.main_form.submit();
}

function add_book_to_chart(navigation) {
	document.main_form.navigation.value = navigation;
	document.main_form.add_to_chart.value = 'ok';
	document.main_form.submit();
}

function update_chart(navigation) {
	document.main_form.navigation.value = navigation;
	document.main_form.update.value = 'ok';
	document.main_form.submit();
}

function show_text(text_id) {
	document.main_form.navigation.value = 'text';
	document.main_form.show_text_id.value = text_id;
	document.main_form.submit();
}

function scrollPages(section, start) {
	document.main_form.navigation.value = section;
	document.main_form.start.value = start;
	document.main_form.submit();
}