package compbio.controllers;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Collection;

import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;

import compbio.cassandra.DateFormatter;
import compbio.cassandra.readers.CassandraReader;

/**
 * ProteoCache Basic controller. All other controllers should inherit this
 * controller. Currently BasicController provides user role checks and some
 * global dates for the system (current and the earliest date of executing job)
 * 
 * @author Alexander Sherstnev
 * @version 1.0
 * @since Dec 2013
 */
public class BasicController {
	final protected SimpleDateFormat formaterDDMMYY = DateFormatter.getFormatDDMMYY();
	final protected SimpleDateFormat formaterYYMMDD = DateFormatter.getFormatYYMMDD();

	/**
	 * give the user (principal) name
	 * 
	 * @return the user name. If the user uses LDAP credentials LDAP prefix is
	 *         set
	 */
	protected String getPrincipalName() {
		Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal();
		if (principal instanceof UserDetails) {
			UserDetails details = (UserDetails) principal;
			String rolefix = "";
			String role = details.getUsername();
			Collection<? extends GrantedAuthority> au = details.getAuthorities();
			for (GrantedAuthority ga : au) {
				if (ga.getAuthority().equals("ROLE_LDAP_USER")) {
					rolefix = "LDAP:";
				}
			}
			return rolefix + role;
		}
		return principal.toString();
	}

	/**
	 * check whether the current user has standard user permissions (ROLE_USER
	 * or ROLE_LDAP_USER)
	 * 
	 * @return true if this is a ROLE_USER/ROLE_LDAP_USER user, false otherwise
	 */
	protected boolean isUserRole() {
		Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal();
		if (principal instanceof UserDetails) {
			UserDetails details = (UserDetails) principal;
			Collection<? extends GrantedAuthority> au = details.getAuthorities();
			for (GrantedAuthority ga : au) {
				if (ga.getAuthority().equals("ROLE_USER") || ga.getAuthority().equals("ROLE_LDAP_USER")) {
					return true;
				}
			}
			return false;
		}
		return false;
	}

	/**
	 * check whether the current user has administrator permissions (ROLE_ADMIN)
	 * 
	 * @return true if this is a ROLE_ADMIN user, false otherwise
	 */
	protected boolean isAdminRole() {
		Object principal = SecurityContextHolder.getContext().getAuthentication().getPrincipal();
		if (principal instanceof UserDetails) {
			UserDetails details = (UserDetails) principal;
			Collection<? extends GrantedAuthority> au = details.getAuthorities();
			for (GrantedAuthority ga : au) {
				if (ga.getAuthority().equals("ROLE_ADMIN")) {
					return true;
				}
			}
			return false;
		}
		return false;
	}

	/**
	 * check whether provided dates are ordered properly and within permitted
	 * time range
	 * 
	 * @param date1
	 *            early limit of the time range)
	 * 
	 *            * @param date2 late limit of the time range)
	 * 
	 *            * @param longDate1 date 1 in the numerical represenation (in
	 *            milliseconds)
	 * 
	 *            * @param longDate2 date 2 in the numerical represenation (in
	 *            milliseconds)
	 * 
	 * @return true if these dates are correct, false otherwise
	 */
	protected String checkDates(String date1, String date2, long longDate1, long longDate2) {
		Calendar cal2 = Calendar.getInstance();
		if (date1.equalsIgnoreCase("") || date2.equalsIgnoreCase(""))
			return "The date can not be empty strinfs";
		else if (!DateFormatter.isThisDateValid(date1, formaterYYMMDD) || !DateFormatter.isThisDateValid(date2, formaterYYMMDD))
			return "The date format in invalid. The format yyyy/mm/dd should be used";
		else if (longDate2 < CassandraReader.earliestDate())
			return "The date2 is earlier than the earliest date in the system " + getEarliestDate();
		else if (longDate1 > cal2.getTimeInMillis())
			return "The date1 is later than the current date " + getCurrentDate();
		else if (longDate1 > longDate2)
			return "Wrong date range. The date1 is later than date2.";

		return null;
	}

	/**
	 * gives the current date in the form of string (yyyy/mm/dd)
	 * 
	 * @return the current date
	 */
	protected String getCurrentDate() {
		Calendar cal = Calendar.getInstance();
		String date = cal.get(Calendar.YEAR) + "/" + (cal.get(Calendar.MONTH) + 1) + "/" + cal.get(Calendar.DAY_OF_MONTH);
		return date;
	}

	/**
	 * gives the earliest date in the system (through a direct call of a
	 * Cassandra related class) in the form of string (yyyy/mm/dd)
	 * 
	 * @return the current date
	 */
	protected String getEarliestDate() {
		return DateFormatter.DateLongToString(CassandraReader.earliestDate(), formaterYYMMDD);
	}
}