/*---------------------------------------------------------------------------#
	# Creation date :-> 05-04-2005 [dd-mm-yyyy]                                  #
	# Last update   :-> 06-04-2006 [dd-mm-yyyy]                                  #
	# --------------------------------------------------------------------------*/

function checkForm(theForm) {
	var message = "";
	
	/*********** express your interest *********/
	if(theForm._action_.value == "_interest_") {
		if(theForm.title.value == "") {
			message = message + "Please enter your title!\n";
		}
		if(theForm.firstname.value == "") {
			message = message + "Please enter firstname!\n";
		}
		if(theForm.lastname.value == "") {
			message = message + "Please enter lastname!\n";
		}
		if(theForm.organisation.value == "") {
			message = message + "Please enter organisation!\n";
		}
		if(theForm.town.value == "") {
			message = message + "Please enter town!\n";
		}
		if(theForm.country.value == "") {
			message = message + "Please enter country!\n";
		}
		if(theForm.email.value == "") {
			message = message + "Please enter email address!\n";
		}
	}
	
	/*********** new corresponding author *********/
	else if(theForm._action_.value == "_corresponding_author_" || theForm._action_.value == "_corresponding_author_edit_") {
		if(theForm.lastname.value == "") {
			message = message + "Please enter lastname!\n";
		}
		if(theForm.firstname.value == "") {
			message = message + "Please enter firstname!\n";
		}
		if(theForm.salutation.value == "") {
			message = message + "Please enter salutation!\n";
		}
		if(theForm.title.value == "") {
			message = message + "Please enter your title!\n";
		}
		if(theForm.organisation.value == "") {
			message = message + "Please enter university/company!\n";
		}
		if(theForm.address.value == "") {
			message = message + "Please enter address!\n";
		}
		if(theForm.postcode.value == "") {
			message = message + "Please enter postcode/zip code!\n";
		}
		if(theForm.town.value == "") {
			message = message + "Please enter town!\n";
		}
		if(theForm.country.value == "") {
			message = message + "Please enter country!\n";
		}
		if(theForm.email.value == "") {
			message = message + "Please enter email address!\n";
		}
	}
	
	/*********** register new paper *********/
	else if(theForm._action_.value == "_register_new_paper_" || theForm._action_.value == "_edit_paper_data_") {
		if(theForm.paper_title.value == "") {
			message = message + "Please enter title!\n";
		}
		if(theForm.noAuthors.value == "0") {
			message = message + "Please enter please enter all authors!\n";
		} else {
			var i = 0;
			for(i=1; i<=theForm.noAuthors.value; i++) {
				if(theForm.elements['authorFirstname['+i+']'].value == "") {
					message = message + "Please enter firstname for author no. " + i + "!\n";
				}
				if(theForm.elements['authorLastname['+i+']'].value == "") {
					message = message + "Please enter lastname for author no. " + i + "!\n";
				}
				if(theForm.elements['authorEmail['+i+']'].value == "") {
					message = message + "Please enter email address for author no. " + i + "!\n";
				}
			}
		}
		if(theForm.keywords.value == "") {
			message = message + "Please enter keywords!\n";
		}
		if(theForm.topic_primarily.value == "0") {
			message = message + "Please enter topic primarily!\n";
		}
		if(theForm._action_.value == "_register_new_paper_") {
			if(theForm.papername.value == "") {
			message = message + "Please select full paper file to upload!\n";
			}
		}
	}
	
	/*********** upload new version of paper *********/
	else if(theForm._action_.value == "_upload_new_version_of_paper_") {
		var i = 0;
		var PaperSelected = false;
		for(i=0; i<theForm.noPapers.value; i++) {
			if(theForm.elements[i].checked) {
				PaperSelected = true;
			}
		}
		if(PaperSelected == false) {
			message = message + "Please select paper!\n";
		}
		if(theForm.papername.value == "") {
			message = message + "Please select new version of paper file!\n";
		}
	}
	
	/*********** _submit_presentation_ *********/
	else if(theForm._action_.value == "_submit_presentation_") {
		var i = 0;
		var PaperSelected = false;
		for(i=0; i<theForm.noPapers.value; i++) {
			if(theForm.elements[i].checked) {
				PaperSelected = true;
			}
		}
		if(PaperSelected == false) {
			message = message + "Please select paper!\n";
		}
		
		if(theForm.lastname.value == "") {
			message = message + "Please enter presenting author lastname!\n";
		}
		if(theForm.firstname.value == "") {
			message = message + "Please enter presenting author firstname!\n";
		}
		if(theForm.title.value == "") {
			message = message + "Please enter presenting author title!\n";
		}
		if(theForm.organisation.value == "") {
			message = message + "Please enter presenting author university/company!\n";
		}
		if(theForm.country.value == "") {
			message = message + "Please enter country!\n";
		}
		if(theForm.email.value == "") {
			message = message + "Please enter email address!\n";
		}
		if(theForm.biography.value == "") {
			message = message + "Please enter presenting author biography!\n";
		}
		if(theForm.presentation.value == "") {
			message = message + "Please select the PowerPoint file to upload!\n";
		}
	}
	
	/*********** _edit_presentation_ *********/
	else if(theForm._action_.value == "_edit_presentation_") {
		if(theForm.lastname.value == "") {
			message = message + "Please enter presenting author lastname!\n";
		}
		if(theForm.firstname.value == "") {
			message = message + "Please enter presenting author firstname!\n";
		}
		if(theForm.title.value == "") {
			message = message + "Please enter presenting author title!\n";
		}
		if(theForm.organisation.value == "") {
			message = message + "Please enter presenting author university/company!\n";
		}
		if(theForm.biography.value == "") {
			message = message + "Please enter presenting author biography!\n";
		}
	}
	
	/*********** upload new version of presentation *********/
	else if(theForm._action_.value == "_upload_new_version_of_presentation_") {
		var i = 0;
		var PaperSelected = false;
		for(i=0; i<theForm.noPapers.value; i++) {
			if(theForm.elements[i].checked) {
				PaperSelected = true;
			}
		}
		if(PaperSelected == false) {
			message = message + "Please select paper!\n";
		}
		if(theForm.presentation.value == "") {
			message = message + "Please select new version of PowerPoint file!\n";
		}
	}
	
	if(message.length > 0) {
		alert(message);
		return false;
	} else {
		return true;
	}
} // end of the 'checkForm()' function