/**
 *    PermissionPair.java
 *    Copyright (C) 2010 New Zealand Digital Library, http://expeditee.org
 *
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.expeditee.items;

import java.util.Arrays;
import java.util.List;

import org.expeditee.settings.UserSettings;

public class PermissionTriple {

	private UserAppliedPermission ownerPermission;
	private UserAppliedPermission groupPermission;
	private UserAppliedPermission otherPermission;

	public PermissionTriple(String permissionCode, UserAppliedPermission defaultPermission) {
		ownerPermission = defaultPermission;
		groupPermission = defaultPermission;
		otherPermission = defaultPermission;
		
		if (permissionCode != null && permissionCode.length() > 0) {
			permissionCode = permissionCode.trim().toLowerCase();
			
			int numberOfMinuses = permissionCode.chars().reduce(0, (a, b) -> b == '-' ? a + 1 : a);
			String[] codes = new String[3];
			Arrays.fill(codes, "");
			if (permissionCode.length() == 1 + numberOfMinuses) {
				codes[0] = permissionCode;
			} else {
				int i = 0;
				for (char c : permissionCode.toCharArray()) {
					try {
						int asInt = Integer.parseInt(c + "");
						codes[i] += asInt + "";
						i++;
					} catch (NumberFormatException e) {
						if (c == '-') {
							codes[i] += c + ""; 
						}
					}
				}
			}

			this.ownerPermission = UserAppliedPermission.getPermission(codes[0], this.ownerPermission);
			if (codes[1].length() == 0) { // If there is only a permission code for owner.
				this.groupPermission = UserAppliedPermission.getPermission(codes[0], this.groupPermission);
				this.otherPermission = UserAppliedPermission.getPermission(codes[0], this.otherPermission);
			} else if (codes[2].length() == 0) { // If there is only two of three permission codes specified.
				this.groupPermission = UserAppliedPermission.getPermission(codes[1], this.groupPermission);
				this.otherPermission = UserAppliedPermission.getPermission(codes[1], this.otherPermission);
			} else { // If all permission codes are specified.
				this.groupPermission = UserAppliedPermission.getPermission(codes[1], this.groupPermission);
				this.otherPermission = UserAppliedPermission.getPermission(codes[2], this.otherPermission);
			}
		}
	}

	public PermissionTriple(UserAppliedPermission ownerPermission, UserAppliedPermission groupPermission, UserAppliedPermission otherPermission) {
		this.ownerPermission = ownerPermission;
		this.groupPermission = groupPermission;
		this.otherPermission = otherPermission;
	}

	public PermissionTriple(UserAppliedPermission permissionForAll) {
		this(permissionForAll, permissionForAll, permissionForAll);
	}

	public PermissionTriple(PermissionTriple pt) {
		this.ownerPermission = pt.ownerPermission;
		this.groupPermission = pt.groupPermission;
		this.otherPermission = pt.otherPermission;
	}

	public UserAppliedPermission getPermission(String ownerOfItem, List<String> group) {
		if (UserSettings.UserName.get().equals(ownerOfItem)) {
			return ownerPermission;
		} else if (group.contains(UserSettings.UserName.get())) {
			return groupPermission;
		} else {
			return otherPermission;
		}
	}

	/**
	 * Converts the given Expeditee permission code into a PermissionPair
	 * corresponding to the constants defined in Item.
	 * 
	 * @param permissionCode
	 *            The Expeditee permission code to convert
	 * @return The resulting PermissionPair corresponding to a pair of constants as
	 *         defined in Item
	 */
	public static PermissionTriple convertString(String permissionCode) {
		PermissionTriple pt = new PermissionTriple(permissionCode, UserAppliedPermission.full);
		return pt;
	}

	public String getCode() {
		return Integer.toString(ownerPermission.getCode()) + Integer.toString(groupPermission.getCode()) + Integer.toString(otherPermission.getCode());
	}

	@Override
	public String toString() {
		return ownerPermission + ":" + groupPermission + ":" + otherPermission;
	}
}