// $Id$
/*
 * WorldEdit
 * Copyright (C) 2010 sk89q <http://www.sk89q.com>
 *
 * 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 com.sk89q.bukkit.migration;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.HashMap;

public class FlatFilePermissionsResolver implements PermissionsResolver {
    private Map<String,Set<String>> userPermissionsCache;
    private Set<String> defaultPermissionsCache;
    private Map<String,Set<String>> userGroups;
    
    public FlatFilePermissionsResolver() {
    }
    
    public static boolean filesExists() {
        return (new File("perms_groups.txt")).exists()
                && (new File("perms_users.txt")).exists();
    }
    
    public Map<String,Set<String>> loadGroupPermissions() {
        Map<String,Set<String>> userGroupPermissions = new HashMap<String,Set<String>>();

        File file = new File("perms_groups.txt");
        FileReader input = null;

        try {
            input = new FileReader(file);
            BufferedReader buff = new BufferedReader(input);

            String line;
            while ((line = buff.readLine()) != null) {
                line = line.trim();

                // Blank line
                if (line.length() == 0) {
                    continue;
                } else if (line.charAt(0) == ';' || line.charAt(0) == '#') {
                    continue;
                }
                
                String[] parts = line.split(":");
                
                String key = parts[0];
                
                if (parts.length > 1) {
                    String[] perms = parts[1].split(",");

                    Set<String> groupPerms = new HashSet<String>(Arrays.asList(perms));
                    userGroupPermissions.put(key, groupPerms);
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (input != null) {
                    input.close();
                }
            } catch (IOException e2) {
            }
        }
        
        return userGroupPermissions;
    }
    
    public void load() {
        userGroups = new HashMap<String,Set<String>>();
        userPermissionsCache = new HashMap<String,Set<String>>();
        defaultPermissionsCache = new HashSet<String>();

        Map<String,Set<String>> userGroupPermissions = loadGroupPermissions();
        
        if (userGroupPermissions.containsKey("default")) {
            defaultPermissionsCache = userGroupPermissions.get("default");
        }

        File file = new File("perms_users.txt");
        FileReader input = null;

        try {
            input = new FileReader(file);
            BufferedReader buff = new BufferedReader(input);

            String line;
            while ((line = buff.readLine()) != null) {
                Set<String> permsCache = new HashSet<String>();
                
                line = line.trim();

                // Blank line
                if (line.length() == 0) {
                    continue;
                } else if (line.charAt(0) == ';' || line.charAt(0) == '#') {
                    continue;
                }
                
                String[] parts = line.split(":");
                
                String key = parts[0];
                
                if (parts.length > 1) {
                    String[] groups = (parts[1] + ",default").split(",");
                    String[] perms = parts.length > 2 ? parts[2].split(",") : new String[0];

                    permsCache.addAll(Arrays.asList(perms));

                    for (String group : groups) {
                        Set<String> groupPerms = userGroupPermissions.get(group);
                        if (groupPerms != null) {
                            permsCache.addAll(groupPerms);
                        }
                    }

                    userPermissionsCache.put(key.toLowerCase(), permsCache);
                    userGroups.put(key.toLowerCase(), new HashSet<String>(Arrays.asList(groups)));
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (input != null) {
                    input.close();
                }
            } catch (IOException e2) {
            }
        }
    }
    
    public boolean hasPermission(String player, String permission) {
        int dotPos = permission.lastIndexOf(".");
        if (dotPos > -1) {
            if (hasPermission(player, permission.substring(0, dotPos))) {
                return true;
            }
        }
        
        Set<String> perms = userPermissionsCache.get(player.toLowerCase());
        if (perms == null) {
            return defaultPermissionsCache.contains(permission)
                    || defaultPermissionsCache.contains("*");
        }
        
        return perms.contains("*") || perms.contains(permission);        
    }
    
    public boolean inGroup(String player, String group) {
        Set<String> groups = userGroups.get(player.toLowerCase());
        if (groups == null) {
            return false;
        }
        
        return groups.contains(group);        
    }
    
    public String[] getGroups(String player) {
        Set<String> groups = userGroups.get(player.toLowerCase());
        if (groups == null) {
            return new String[0];
        }
        
        return groups.toArray(new String[groups.size()]);        
    }
}