AlttdGriefPrevention/src/me/ryanhamshire/GriefPrevention/DataStore.java

/*
    GriefPrevention Server Plugin for Minecraft
    Copyright (C) 2012 Ryan Hamshire

    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 me.ryanhamshire.GriefPrevention;

import java.io.*;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;

import org.bukkit.*;
import org.bukkit.configuration.file.FileConfiguration;
import org.bukkit.configuration.file.YamlConfiguration;
import org.bukkit.entity.Player;
import org.bukkit.inventory.ItemStack;

//singleton class which manages all GriefPrevention data (except for config options)
public class DataStore 
{
	//in-memory cache for player data
	private HashMap<String, PlayerData> playerNameToPlayerDataMap = new HashMap<String, PlayerData>();
	
	//in-memory cache for group (permission-based) data
	private HashMap<String, Integer> permissionToBonusBlocksMap = new HashMap<String, Integer>();
	
	//in-memory cache for claim data
	ArrayList<Claim> claims = new ArrayList<Claim>();
	
	//in-memory cache for messages
	private String [] messages;
	
	//path information, for where stuff stored on disk is well...  stored
	private final static String dataLayerFolderPath = "plugins" + File.separator + "GriefPreventionData";
	private final static String playerDataFolderPath = dataLayerFolderPath + File.separator + "PlayerData";
	private final static String claimDataFolderPath = dataLayerFolderPath + File.separator + "ClaimData";
	final static String configFilePath = dataLayerFolderPath + File.separator + "config.yml";
	final static String messagesFilePath = dataLayerFolderPath + File.separator + "messages.yml";
	
	//initialization!
	DataStore()
	{
		//ensure data folders exist
		new File(playerDataFolderPath).mkdirs();
		new File(claimDataFolderPath).mkdirs();
		
		//load group data into memory
		File playerDataFolder = new File(playerDataFolderPath);
		File [] files = playerDataFolder.listFiles();
		for(int i = 0; i < files.length; i++)
		{
			File file = files[i];
			if(!file.isFile()) continue;  //avoids folders
			
			//all group data files start with an underscore.  ignoring the rest, which are player data files.			
			if(!file.getName().startsWith("$")) continue;
			
			String groupName = file.getName().substring(1);
			if(groupName == null || groupName.isEmpty()) continue;  //defensive coding, avoid unlikely cases
			
			BufferedReader inStream = null;
			try
			{
				inStream = new BufferedReader(new FileReader(file.getAbsolutePath()));
				String line = inStream.readLine();
				
				int groupBonusBlocks = Integer.parseInt(line);
				
				this.permissionToBonusBlocksMap.put(groupName, groupBonusBlocks);
			}
			catch(Exception e)
			{
				 GriefPrevention.AddLogEntry("Unable to load group bonus block data from file \"" + file.getName() + "\": " + e.getMessage());
			}
			
			try
			{
				if(inStream != null) inStream.close();					
			}
			catch(IOException exception) {}
		}
		
		//load claims data into memory		
		File claimDataFolder = new File(claimDataFolderPath);
		files = claimDataFolder.listFiles();
		
		int loadedClaimCount = 0;
		
		for(int i = 0; i < files.length; i++)
		{			
			if(files[i].isFile())  //avoids folders
			{
				BufferedReader inStream = null;
				try
				{					
					Claim topLevelClaim = null;
					
					inStream = new BufferedReader(new FileReader(files[i].getAbsolutePath()));
					String line = inStream.readLine();
					
					while(line != null)
					{					
						//first line is lesser boundary corner location
						Location lesserBoundaryCorner = this.locationFromString(line);
						
						//second line is greater boundary corner location
						line = inStream.readLine();
						Location greaterBoundaryCorner = this.locationFromString(line);
						
						//third line is owner name
						line = inStream.readLine();						
						String ownerName = line;
						
						//fourth line is list of builders
						line = inStream.readLine();
						String [] builderNames = line.split(";");
						
						//fifth line is list of players who can access containers
						line = inStream.readLine();
						String [] containerNames = line.split(";");
						
						//sixth line is list of players who can use buttons and switches
						line = inStream.readLine();
						String [] accessorNames = line.split(";");
						
						//seventh line is list of players who can grant permissions
						line = inStream.readLine();
						if(line == null) line = "";
						String [] managerNames = line.split(";");
						
						//skip any remaining extra lines, until the "===" string, indicating the end of this claim or subdivision
						line = inStream.readLine();
						while(line != null && !line.contains("=========="))
							line = inStream.readLine();
						
						//build a claim instance from those data
						//if this is the first claim loaded from this file, it's the top level claim
						if(topLevelClaim == null)
						{
							//instantiate
							topLevelClaim = new Claim(lesserBoundaryCorner, greaterBoundaryCorner, ownerName, builderNames, containerNames, accessorNames, managerNames);
							
							//search for another claim overlapping this one
							Claim conflictClaim = this.getClaimAt(topLevelClaim.lesserBoundaryCorner, true, null);
							
							//if there is such a claim, delete this file and move on to the next
							if(conflictClaim != null)
							{
								inStream.close();
								files[i].delete();
								line = null;
								continue;
							}
							
							//otherwise, add this claim to the claims collection
							else
							{
								topLevelClaim.modifiedDate = new Date(files[i].lastModified());
								int j = 0;
								while(j < this.claims.size() && !this.claims.get(j).greaterThan(topLevelClaim)) j++;
								if(j < this.claims.size())
									this.claims.add(j, topLevelClaim);
								else
									this.claims.add(this.claims.size(), topLevelClaim);
								topLevelClaim.inDataStore = true;								
							}
						}
						
						//otherwise there's already a top level claim, so this must be a subdivision of that top level claim
						else
						{
							Claim subdivision = new Claim(lesserBoundaryCorner, greaterBoundaryCorner, "--subdivision--", builderNames, containerNames, accessorNames, managerNames);
							
							//make sure there are no other subdivisions overlapping this one
							
							subdivision.modifiedDate = new Date(files[i].lastModified());
							subdivision.parent = topLevelClaim;
							topLevelClaim.children.add(subdivision);
							subdivision.inDataStore = true;
						}
						
						//move up to the first line in the next subdivision
						line = inStream.readLine();
					}
					
					inStream.close();
					  
					loadedClaimCount++;
				}
				
				//if there's any problem with the file's content, log an error message and skip it
				catch(Exception e)
				{
					 GriefPrevention.AddLogEntry("Unable to load data for claim \"" + files[i].getName() + "\": " + e.getMessage());
				}
				
				try
				{
					if(inStream != null) inStream.close();					
				}
				catch(IOException exception) {}
			}
		}
		
		GriefPrevention.AddLogEntry(loadedClaimCount + " total claims loaded.");
		
		//make a list of players who own claims
		Vector<String> playerNames = new Vector<String>();
		for(int i = 0; i < this.claims.size(); i++)
		{
			Claim claim = this.claims.get(i);
			
			//ignore admin claims
			if(claim.isAdminClaim()) continue;
			
			if(!playerNames.contains(claim.ownerName))
				playerNames.add(claim.ownerName);
		}
		
		GriefPrevention.AddLogEntry(playerNames.size() + " players have staked claims.");
		
		//load each of these players and determine whether his claims should be cleaned up
		for(int i = 0; i < playerNames.size(); i++)
		{
			String playerName = playerNames.get(i);
			
			PlayerData playerData = this.getPlayerData(playerName);
			
			int areaOfDefaultClaim = 0;
			
			//determine area of the default chest claim
			if(GriefPrevention.instance.config_claims_automaticClaimsForNewPlayersRadius >= 0)
			{
				areaOfDefaultClaim = (int)Math.pow(GriefPrevention.instance.config_claims_automaticClaimsForNewPlayersRadius * 2 + 1, 2);  
			}
			
			//figure out how long the player has been away
			Calendar sevenDaysAgo = Calendar.getInstance();
			sevenDaysAgo.add(Calendar.DATE, -7);
			boolean claimsExpired = sevenDaysAgo.getTime().after(playerData.lastLogin);
			
			//if only one claim, and the player hasn't played in a week
			if(claimsExpired && playerData.claims.size() == 1)
			{
				Claim claim = playerData.claims.get(0);
				
				//if that's a chest claim, delete it
				if(claim.getArea() <= areaOfDefaultClaim)
				{
					claim.removeSurfaceFluids(null);
					this.deleteClaim(claim);
					GriefPrevention.AddLogEntry(" " + playerName + "'s new player claim expired.");
				}
			}
			
			if(GriefPrevention.instance.config_claims_expirationDays > 0)
			{
				Calendar earliestPermissibleLastLogin = Calendar.getInstance();
				earliestPermissibleLastLogin.add(Calendar.DATE, -GriefPrevention.instance.config_claims_expirationDays);
				
				if(earliestPermissibleLastLogin.getTime().after(playerData.lastLogin))
				{
					this.deleteClaimsForPlayer(playerName, true);
					GriefPrevention.AddLogEntry(" All of " + playerName + "'s claims have expired.");
				}
			}
			
			//toss that player data out of the cache, it's not needed in memory right now
			this.clearCachedPlayerData(playerName);
		}
		
		//load up all the messages from messages.yml
		this.loadMessages();
		
		//collect garbage, since lots of stuff was loaded into memory and then tossed out
		System.gc();
	}
	
	//removes cached player data from memory
	void clearCachedPlayerData(String playerName)
	{
		this.playerNameToPlayerDataMap.remove(playerName);
	}
	
	//gets the number of bonus blocks a player has from his permissions
	int getGroupBonusBlocks(String playerName)
	{
		int bonusBlocks = 0;
		Set<String> keys = permissionToBonusBlocksMap.keySet();
		Iterator<String> iterator = keys.iterator();
		while(iterator.hasNext())
		{
			String groupName = iterator.next();
			Player player = GriefPrevention.instance.getServer().getPlayer(playerName);
			if(player.hasPermission(groupName))
			{
				bonusBlocks += this.permissionToBonusBlocksMap.get(groupName);
			}
		}
		
		return bonusBlocks;
	}
	
	//grants a group (players with a specific permission) bonus claim blocks as long as they're still members of the group
	public int adjustGroupBonusBlocks(String groupName, int amount)
	{
		Integer currentValue = this.permissionToBonusBlocksMap.get(groupName);
		if(currentValue == null) currentValue = 0;
		
		currentValue += amount;
		this.permissionToBonusBlocksMap.put(groupName, currentValue);
		
		//write changes to file to ensure they don't get lost
		BufferedWriter outStream = null;
		try
		{
			//open the group's file
			File groupDataFile = new File(playerDataFolderPath + File.separator + "$" + groupName);
			groupDataFile.createNewFile();
			outStream = new BufferedWriter(new FileWriter(groupDataFile));
			
			//first line is number of bonus blocks
			outStream.write(currentValue.toString());
			outStream.newLine();			
		}		
		
		//if any problem, log it
		catch(Exception e)
		{
			GriefPrevention.AddLogEntry("Unexpected exception saving data for group \"" + groupName + "\": " + e.getMessage());
		}
		
		try
		{
			//close the file
			if(outStream != null)
			{
				outStream.close();
			}
		}
		catch(IOException exception){}
		
		return currentValue;		
	}
	
	public void changeClaimOwner(Claim claim, String newOwnerName) throws Exception
	{
		//if it's a subdivision, throw an exception
		if(claim.parent != null)
		{
			throw new Exception("Subdivisions can't be transferred.  Only top-level claims may change owners.");
		}
		
		//otherwise update information
		
		//determine current claim owner
		PlayerData ownerData = null;
		if(!claim.isAdminClaim())
		{
			ownerData = this.getPlayerData(claim.ownerName);
		}
		
		//determine new owner
		PlayerData newOwnerData = this.getPlayerData(newOwnerName);
		
		//transfer
		claim.ownerName = newOwnerName;
		this.saveClaim(claim);
		
		//adjust blocks and other records
		if(ownerData != null)
		{
			ownerData.claims.remove(claim);
			ownerData.bonusClaimBlocks -= claim.getArea();
			this.savePlayerData(claim.ownerName, ownerData);
		}
		
		newOwnerData.claims.add(claim);
		newOwnerData.bonusClaimBlocks += claim.getArea();
		this.savePlayerData(newOwnerName, newOwnerData);
	}

	//adds a claim to the datastore, making it an effective claim
	void addClaim(Claim newClaim)
	{
		//subdivisions are easy
		if(newClaim.parent != null)
		{
			newClaim.parent.children.add(newClaim);
			newClaim.inDataStore = true;
			this.saveClaim(newClaim);
			return;
		}
		
		//add it and mark it as added
		int j = 0;
		while(j < this.claims.size() && !this.claims.get(j).greaterThan(newClaim)) j++;
		if(j < this.claims.size())
			this.claims.add(j, newClaim);
		else
			this.claims.add(this.claims.size(), newClaim);
		newClaim.inDataStore = true;
		
		//except for administrative claims (which have no owner), update the owner's playerData with the new claim
		if(!newClaim.isAdminClaim())
		{
			PlayerData ownerData = this.getPlayerData(newClaim.getOwnerName());
			ownerData.claims.add(newClaim);
			this.savePlayerData(newClaim.getOwnerName(), ownerData);
		}
		
		//make sure the claim is saved to disk
		this.saveClaim(newClaim);
	}
	
	//turns a location into a string, useful in data files and data file names
	private String locationStringDelimiter = ";";	
	private String locationToString(Location location)
	{
		StringBuilder stringBuilder = new StringBuilder(location.getWorld().getName());
		stringBuilder.append(locationStringDelimiter);
		stringBuilder.append(location.getBlockX());
		stringBuilder.append(locationStringDelimiter);
		stringBuilder.append(location.getBlockY());
		stringBuilder.append(locationStringDelimiter);
		stringBuilder.append(location.getBlockZ());
		
		return stringBuilder.toString();
	}
	
	//turns a location string back into a location
	private Location locationFromString(String string) throws Exception
	{
		//split the input string on the space
		String [] elements = string.split(locationStringDelimiter);
	    
		//expect four elements - world name, X, Y, and Z, respectively
		if(elements.length != 4)
		{
			throw new Exception("Expected four distinct parts to the location string.");
		}
		
		String worldName = elements[0];
		String xString = elements[1];
		String yString = elements[2];
		String zString = elements[3];
	    
		//identify world the claim is in
		World world = GriefPrevention.instance.getServer().getWorld(worldName);
		if(world == null)
		{
			throw new Exception("World not found: \"" + worldName + "\"");
		}
		
		//convert those numerical strings to integer values
	    int x = Integer.parseInt(xString);
	    int y = Integer.parseInt(yString);
	    int z = Integer.parseInt(zString);
	    
	    return new Location(world, x, y, z);
	}	

	//does the work of actually writing a claim to file
	public void saveClaim(Claim claim)
	{
		//subdivisions don't save to their own files, but instead live in their parent claim's file
		//so any attempt to save a subdivision will save its parent (and thus the subdivision)
		if(claim.parent != null)
		{
			this.saveClaim(claim.parent);
			return;
		}
		
		//otherwise get a unique identifier for the claim which will be used to name the file on disk
		String claimID = this.getClaimID(claim);
		
		BufferedWriter outStream = null;
		
		try
		{
			//open the claim's file						
			File claimFile = new File(claimDataFolderPath + File.separator + claimID);
			claimFile.createNewFile();
			outStream = new BufferedWriter(new FileWriter(claimFile));
			
			this.writeClaimData(claim, outStream);
			
			for(int i = 0; i < claim.children.size(); i++)
			{
				//see below for details of writing data to file
				this.writeClaimData(claim.children.get(i), outStream);
			}
		}		
		
		//if any problem, log it
		catch(Exception e)
		{
			GriefPrevention.AddLogEntry("PopulationDensity: Unexpected exception saving data for claim \"" + claimID + "\": " + e.getMessage());
		}
		
		//close the file
		try
		{
			if(outStream != null) outStream.close();
		}
		catch(IOException exception) {}
	}
	
	//actually writes claim data to an output stream
	private void writeClaimData(Claim claim, BufferedWriter outStream) throws IOException
	{
		String claimID = this.getClaimID(claim);
		
		//first line is lesser boundary corner location
		outStream.write(claimID);
		outStream.newLine();
		
		//second line is greater boundary corner location
		outStream.write(this.locationToString(claim.getGreaterBoundaryCorner()));
		outStream.newLine();
		
		//third line is owner name
		outStream.write(claim.ownerName);
		outStream.newLine();
		
		ArrayList<String> builders = new ArrayList<String>();
		ArrayList<String> containers = new ArrayList<String>();
		ArrayList<String> accessors = new ArrayList<String>();
		ArrayList<String> managers = new ArrayList<String>();
		
		claim.getPermissions(builders, containers, accessors, managers);
		
		//fourth line is list of players with build permission
		for(int i = 0; i < builders.size(); i++)
		{
			outStream.write(builders.get(i) + ";");
		}
		outStream.newLine();
		
		//fifth line is list of players with container permission
		for(int i = 0; i < containers.size(); i++)
		{
			outStream.write(containers.get(i) + ";");
		}
		outStream.newLine();
		
		//sixth line is list of players with access permission
		for(int i = 0; i < accessors.size(); i++)
		{
			outStream.write(accessors.get(i) + ";");
		}
		outStream.newLine();
		
		//seventh line is list of players who may grant permissions for others
		for(int i = 0; i < managers.size(); i++)
		{
			outStream.write(managers.get(i) + ";");
		}
		outStream.newLine();
		
		//cap each claim with "=========="
		outStream.write("==========");
		outStream.newLine();
	}
	
	//retrieves player data from memory or file, as necessary
	//if the player has never been on the server before, this will return a fresh player data with default values
	public PlayerData getPlayerData(String playerName)
	{
		//first, look in memory
		PlayerData playerData = this.playerNameToPlayerDataMap.get(playerName);
		
		//if not there, look on disk
		if(playerData == null)
		{
			File playerFile = new File(playerDataFolderPath + File.separator + playerName);
					
			playerData = new PlayerData();
			playerData.playerName = playerName;
			
			//if it doesn't exist as a file
			if(!playerFile.exists())
			{
				//create a file with defaults
				this.savePlayerData(playerName, playerData);
			}
			
			//otherwise, read the file
			else
			{			
				BufferedReader inStream = null;
				try
				{					
					inStream = new BufferedReader(new FileReader(playerFile.getAbsolutePath()));
					
					//first line is last login timestamp
					String lastLoginTimestampString = inStream.readLine();
					
					//convert that to a date and store it
				    DateFormat dateFormat = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss");					
					try
					{
						playerData.lastLogin = dateFormat.parse(lastLoginTimestampString);
					}
					catch(ParseException parseException)
					{
						GriefPrevention.AddLogEntry("Unable to load last login for \"" + playerFile.getName() + "\".");
						playerData.lastLogin = null;
					}
					
					//second line is accrued claim blocks
					String accruedBlocksString = inStream.readLine();
					
					//convert that to a number and store it
					playerData.accruedClaimBlocks = Integer.parseInt(accruedBlocksString);
					
					//third line is any bonus claim blocks granted by administrators
					String bonusBlocksString = inStream.readLine();					
					
					//convert that to a number and store it										
					playerData.bonusClaimBlocks = Integer.parseInt(bonusBlocksString);
					
					//fourth line is a double-semicolon-delimited list of claims, which is currently ignored
					//String claimsString = inStream.readLine();
					inStream.readLine();
					/*
					if(claimsString != null && claimsString.length() > 0)
					{
						String [] claimsStrings = claimsString.split(";;");
						boolean missingClaim = false;
						
						//search for each claim mentioned in the file
						for(int i = 0; i < claimsStrings.length; i++)
						{
							String claimID = claimsStrings[i];
							if(claimID != null)
							{
								Claim claim = this.getClaimAt(this.locationFromString(claimID), true, null);
								
								//if the referenced claim exists, add it to the player data instance for later reference
								if(claim != null)
								{
									playerData.claims.add(claim);
								}
								
								//if the claim doesn't seem to exist anymore, plan to drop the reference from the file
								else
								{
									missingClaim = true;
								}
							}
						}
						
						//if any referenced claims no longer exist, write the player data back to file to eliminate those references
						if(missingClaim)
						{
							this.savePlayerData(playerName, playerData);
						}
					}
					*/
					
					//find all the claims belonging to this player and note them for future reference
					for(int i = 0; i < this.claims.size(); i++)
					{
						Claim claim = this.claims.get(i);
						if(claim.ownerName.equals(playerName))
						{
							playerData.claims.add(claim);
						}
					}
					
					inStream.close();
				}
					
				//if there's any problem with the file's content, log an error message
				catch(Exception e)
				{
					 GriefPrevention.AddLogEntry("Unable to load data for player \"" + playerName + "\": " + e.getMessage());			 
				}
				
				try
				{
					if(inStream != null) inStream.close();
				}
				catch(IOException exception) {}
			}
			
			//shove that new player data into the hash map cache
			this.playerNameToPlayerDataMap.put(playerName, playerData);
		}
		
		//try the hash map again.  if it's STILL not there, we have a bug to fix
		return this.playerNameToPlayerDataMap.get(playerName);
	}
	
	//deletes a claim or subdivision
	public void deleteClaim(Claim claim)
	{
		//subdivisions are simple - just remove them from their parent claim and save that claim
		if(claim.parent != null)
		{
			Claim parentClaim = claim.parent;
			parentClaim.children.remove(claim);
			this.saveClaim(parentClaim);
			return;
		}
		
		//otherwise, need to update the data store and ensure the claim's file is deleted		
		String claimID = this.getClaimID(claim);
		
		//remove from memory
		for(int i = 0; i < this.claims.size(); i++)
		{
			if(this.getClaimID(this.claims.get(i)).equals(claimID))
			{
				this.claims.remove(i);
				claim.inDataStore = false;
				for(int j = 0; j < claim.children.size(); j++)
				{
					claim.children.get(j).inDataStore = false;
				}
				break;
			}
		}
		
		//remove from disk
		File claimFile = new File(claimDataFolderPath + File.separator + claimID);
		if(claimFile.exists() && !claimFile.delete())
		{
			GriefPrevention.AddLogEntry("Error: Unable to delete claim file \"" + claimFile.getAbsolutePath() + "\".");
		}
		
		//update player data, except for administrative claims, which have no owner
		if(!claim.isAdminClaim())
		{
			PlayerData ownerData = this.getPlayerData(claim.getOwnerName());
			for(int i = 0; i < ownerData.claims.size(); i++)
			{
				if(this.getClaimID(ownerData.claims.get(i)).equals(claimID))
				{
					ownerData.claims.remove(i);
					break;
				}
			}
			this.savePlayerData(claim.getOwnerName(), ownerData);
		}
	}
	
	//gets the claim at a specific location
	//ignoreHeight = TRUE means that a location UNDER an existing claim will return the claim
	//cachedClaim can be NULL, but will help performance if you have a reasonable guess about which claim the location is in
	public Claim getClaimAt(Location location, boolean ignoreHeight, Claim cachedClaim)
	{
		//check cachedClaim guess first.  if it's in the datastore and the location is inside it, we're done
		if(cachedClaim != null && cachedClaim.inDataStore && cachedClaim.contains(location, ignoreHeight, true)) return cachedClaim;
		
		//the claims list is ordered by greater boundary corner
		//create a temporary "fake" claim in memory for comparison purposes		
		Claim tempClaim = new Claim();
		tempClaim.lesserBoundaryCorner = location;
		
		//otherwise, search all existing claims until we find the right claim
		for(int i = 0; i < this.claims.size(); i++)
		{
			Claim claim = this.claims.get(i);
			
			//if we reach a claim which is greater than the temp claim created above, there's definitely no claim
			//in the collection which includes our location
			if(claim.greaterThan(tempClaim)) return null;
			
			//find a top level claim
			if(claim.contains(location, ignoreHeight, false))
			{
				//when we find a top level claim, if the location is in one of its subdivisions,
				//return the SUBDIVISION, not the top level claim
				for(int j = 0; j < claim.children.size(); j++)
				{
					Claim subdivision = claim.children.get(j);
					if(subdivision.contains(location, ignoreHeight, false)) return subdivision;
				}						
					
				return claim;
			}
		}
		
		//if no claim found, return null
		return null;
	}
	
	//creates a claim.
	//if the new claim would overlap an existing claim, returns a failure along with a reference to the existing claim
	//otherwise, returns a success along with a reference to the new claim
	//use ownerName == "" for administrative claims
	//for top level claims, pass parent == NULL
	//DOES adjust claim blocks available on success (players can go into negative quantity available)
	//does NOT check a player has permission to create a claim, or enough claim blocks.
	//does NOT check minimum claim size constraints
	//does NOT visualize the new claim for any players	
	public CreateClaimResult createClaim(World world, int x1, int x2, int y1, int y2, int z1, int z2, String ownerName, Claim parent)
	{
		CreateClaimResult result = new CreateClaimResult();
		
		int smallx, bigx, smally, bigy, smallz, bigz;

		//determine small versus big inputs
		if(x1 < x2)
		{
			smallx = x1;
			bigx = x2;
		}
		else
		{
			smallx = x2;
			bigx = x1;
		}
		
		if(y1 < y2)
		{
			smally = y1;
			bigy = y2;
		}
		else
		{
			smally = y2;
			bigy = y1;
		}
		
		if(z1 < z2)
		{
			smallz = z1;
			bigz = z2;
		}
		else
		{
			smallz = z2;
			bigz = z1;
		}
		
		//creative mode claims always go to bedrock
		if(GriefPrevention.instance.config_claims_enabledCreativeWorlds.contains(world))
		{
			smally = 2;
		}
		
		//create a new claim instance (but don't save it, yet)
		Claim newClaim = new Claim(
			new Location(world, smallx, smally, smallz),
			new Location(world, bigx, bigy, bigz),
			ownerName,
			new String [] {}, 
			new String [] {},
			new String [] {},
			new String [] {});
		
		newClaim.parent = parent;
		
		//ensure this new claim won't overlap any existing claims
		ArrayList<Claim> claimsToCheck;
		if(newClaim.parent != null)
		{
			claimsToCheck = newClaim.parent.children;			
		}
		else
		{
			claimsToCheck = this.claims;
		}

		for(int i = 0; i < claimsToCheck.size(); i++)
		{
			Claim otherClaim = claimsToCheck.get(i);
			
			//if we find an existing claim which will be overlapped
			if(otherClaim.overlaps(newClaim))
			{
				//result = fail, return conflicting claim
				result.succeeded = false;
				result.claim = otherClaim;
				return result;
			}
		}
		
		//otherwise add this new claim to the data store to make it effective
		this.addClaim(newClaim);
		
		//then return success along with reference to new claim
		result.succeeded = true;
		result.claim = newClaim;
		return result;
	}
	
	//saves changes to player data.  MUST be called after you're done making changes, otherwise a reload will lose them
	public void savePlayerData(String playerName, PlayerData playerData)
	{
		//never save data for the "administrative" account.  an empty string for claim owner indicates an administrative claim
		if(playerName.length() == 0) return;
		
		BufferedWriter outStream = null;
		try
		{
			//open the player's file
			File playerDataFile = new File(playerDataFolderPath + File.separator + playerName);
			playerDataFile.createNewFile();
			outStream = new BufferedWriter(new FileWriter(playerDataFile));
			
			//first line is last login timestamp
			if(playerData.lastLogin == null)playerData.lastLogin = new Date();
			DateFormat dateFormat = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss");
			outStream.write(dateFormat.format(playerData.lastLogin));
			outStream.newLine();
			
			//second line is accrued claim blocks
			outStream.write(String.valueOf(playerData.accruedClaimBlocks));
			outStream.newLine();			
			
			//third line is bonus claim blocks
			outStream.write(String.valueOf(playerData.bonusClaimBlocks));
			outStream.newLine();						
			
			//fourth line is a double-semicolon-delimited list of claims
			if(playerData.claims.size() > 0)
			{
				outStream.write(this.locationToString(playerData.claims.get(0).getLesserBoundaryCorner()));
				for(int i = 1; i < playerData.claims.size(); i++)
				{
					outStream.write(";;" + this.locationToString(playerData.claims.get(i).getLesserBoundaryCorner()));
				}
			}
			outStream.newLine();
		}		
		
		//if any problem, log it
		catch(Exception e)
		{
			GriefPrevention.AddLogEntry("PopulationDensity: Unexpected exception saving data for player \"" + playerName + "\": " + e.getMessage());
		}
		
		try
		{
			//close the file
			if(outStream != null)
			{
				outStream.close();
			}
		}
		catch(IOException exception){}
	}
	
	//gets a unique identifier for a claim
	private String getClaimID(Claim claim)
	{
		return this.locationToString(claim.getLesserBoundaryCorner());
	}

	//extends a claim to a new depth
	//respects the max depth config variable
	public void extendClaim(Claim claim, int newDepth) 
	{
		if(newDepth < GriefPrevention.instance.config_claims_maxDepth) newDepth = GriefPrevention.instance.config_claims_maxDepth;
		
		if(claim.parent != null) claim = claim.parent;
		
		//delete the claim
		this.deleteClaim(claim);
		
		//re-create it at the new depth
		claim.lesserBoundaryCorner.setY(newDepth);
		claim.greaterBoundaryCorner.setY(newDepth);
		
		//make all subdivisions reach to the same depth
		for(int i = 0; i < claim.children.size(); i++)
		{
			claim.children.get(i).lesserBoundaryCorner.setY(newDepth);
			claim.children.get(i).greaterBoundaryCorner.setY(newDepth);
		}
		
		//save changes
		this.addClaim(claim);
	}

	//starts a siege on a claim
	//does NOT check siege cooldowns, see onCooldown() below
	public void startSiege(Player attacker, Player defender, Claim defenderClaim)
	{
		//fill-in the necessary SiegeData instance
		SiegeData siegeData = new SiegeData(attacker, defender, defenderClaim);
		PlayerData attackerData = this.getPlayerData(attacker.getName());
		PlayerData defenderData = this.getPlayerData(defender.getName());
		attackerData.siegeData = siegeData;
		defenderData.siegeData = siegeData;
		defenderClaim.siegeData = siegeData;
		
		//start a task to monitor the siege
		//why isn't this a "repeating" task?
		//because depending on the status of the siege at the time the task runs, there may or may not be a reason to run the task again
		SiegeCheckupTask task = new SiegeCheckupTask(siegeData);
		siegeData.checkupTaskID = GriefPrevention.instance.getServer().getScheduler().scheduleSyncDelayedTask(GriefPrevention.instance, task, 20L * 30);
	}
	
	//ends a siege
	//either winnerName or loserName can be null, but not both
	public void endSiege(SiegeData siegeData, String winnerName, String loserName, boolean death)
	{
		boolean grantAccess = false;
		
		//determine winner and loser
		if(winnerName == null && loserName != null)
		{
			if(siegeData.attacker.getName().equals(loserName))
			{
				winnerName = siegeData.defender.getName();
			}
			else
			{
				winnerName = siegeData.attacker.getName();
			}
		}
		else if(winnerName != null && loserName == null)
		{
			if(siegeData.attacker.getName().equals(winnerName))
			{
				loserName = siegeData.defender.getName();
			}
			else
			{
				loserName = siegeData.attacker.getName();
			}
		}
		
		//if the attacker won, plan to open the doors for looting
		if(siegeData.attacker.getName().equals(winnerName))
		{
			grantAccess = true;
		}
		
		PlayerData attackerData = this.getPlayerData(siegeData.attacker.getName());
		attackerData.siegeData = null;
		
		PlayerData defenderData = this.getPlayerData(siegeData.defender.getName());	
		defenderData.siegeData = null;

		//start a cooldown for this attacker/defender pair
		Long now = Calendar.getInstance().getTimeInMillis();
		Long cooldownEnd = now + 1000 * 60 * 60;  //one hour from now
		this.siegeCooldownRemaining.put(siegeData.attacker.getName() + "_" + siegeData.defender.getName(), cooldownEnd);
		
		//start cooldowns for every attacker/involved claim pair
		for(int i = 0; i < siegeData.claims.size(); i++)
		{
			Claim claim = siegeData.claims.get(i);
			claim.siegeData = null;
			this.siegeCooldownRemaining.put(siegeData.attacker.getName() + "_" + claim.ownerName, cooldownEnd);
			
			//if doors should be opened for looting, do that now
			if(grantAccess)
			{
				claim.doorsOpen = true;
			}
		}

		//cancel the siege checkup task
		GriefPrevention.instance.getServer().getScheduler().cancelTask(siegeData.checkupTaskID);
		
		//notify everyone who won and lost
		if(winnerName != null && loserName != null)
		{
			GriefPrevention.instance.getServer().broadcastMessage(winnerName + " defeated " + loserName + " in siege warfare!");
		}
		
		//if the claim should be opened to looting
		if(grantAccess)
		{
			Player winner = GriefPrevention.instance.getServer().getPlayer(winnerName);
			if(winner != null)
			{
				//notify the winner
				GriefPrevention.sendMessage(winner, TextMode.Success, Messages.SiegeWinDoorsOpen);
				
				//schedule a task to secure the claims in about 5 minutes
				SecureClaimTask task = new SecureClaimTask(siegeData);
				GriefPrevention.instance.getServer().getScheduler().scheduleSyncDelayedTask(GriefPrevention.instance, task, 20L * 60 * 5);
			}
		}
		
		//if the siege ended due to death, transfer inventory to winner
		if(death)
		{
			Player winner = GriefPrevention.instance.getServer().getPlayer(winnerName);
			Player loser = GriefPrevention.instance.getServer().getPlayer(loserName);
			if(winner != null && loser != null)
			{
				//get loser's inventory, then clear it
				ItemStack [] loserItems = loser.getInventory().getContents();
				loser.getInventory().clear();
				
				//try to add it to the winner's inventory
				for(int j = 0; j < loserItems.length; j++)
				{
					if(loserItems[j] == null || loserItems[j].getType() == Material.AIR || loserItems[j].getAmount() == 0) continue;
					
					HashMap<Integer, ItemStack> wontFitItems = winner.getInventory().addItem(loserItems[j]);
					
					//drop any remainder on the ground at his feet
					Object [] keys = wontFitItems.keySet().toArray();
					Location winnerLocation = winner.getLocation(); 
					for(int i = 0; i < keys.length; i++)
					{
						Integer key = (Integer)keys[i];
						winnerLocation.getWorld().dropItemNaturally(winnerLocation, wontFitItems.get(key));
					}
				}
			}
		}
	}
	
	//timestamp for each siege cooldown to end
	private HashMap<String, Long> siegeCooldownRemaining = new HashMap<String, Long>();

	//whether or not a sieger can siege a particular victim or claim, considering only cooldowns
	public boolean onCooldown(Player attacker, Player defender, Claim defenderClaim)
	{
		Long cooldownEnd = null;
		
		//look for an attacker/defender cooldown
		if(this.siegeCooldownRemaining.get(attacker.getName() + "_" + defender.getName()) != null)
		{
			cooldownEnd = this.siegeCooldownRemaining.get(attacker.getName() + "_" + defender.getName());
			
			if(Calendar.getInstance().getTimeInMillis() < cooldownEnd)
			{
				return true;
			}
			
			//if found but expired, remove it
			this.siegeCooldownRemaining.remove(attacker.getName() + "_" + defender.getName());
		}
		
		//look for an attacker/claim cooldown
		if(cooldownEnd == null && this.siegeCooldownRemaining.get(attacker.getName() + "_" + defenderClaim.ownerName) != null)
		{
			cooldownEnd = this.siegeCooldownRemaining.get(attacker.getName() + "_" + defenderClaim.ownerName);
			
			if(Calendar.getInstance().getTimeInMillis() < cooldownEnd)
			{
				return true;
			}
			
			//if found but expired, remove it
			this.siegeCooldownRemaining.remove(attacker.getName() + "_" + defenderClaim.ownerName);			
		}
		
		return false;
	}

	//extend a siege, if it's possible to do so
	void tryExtendSiege(Player player, Claim claim)
	{
		PlayerData playerData = this.getPlayerData(player.getName());
		
		//player must be sieged
		if(playerData.siegeData == null) return;
		
		//claim isn't already under the same siege
		if(playerData.siegeData.claims.contains(claim)) return;
		
		//admin claims can't be sieged
		if(claim.isAdminClaim()) return;
		
		//player must have some level of permission to be sieged in a claim
		if(claim.allowAccess(player) != null) return;
		
		//otherwise extend the siege
		playerData.siegeData.claims.add(claim);
		claim.siegeData = playerData.siegeData;
	}		
	
	//deletes all claims owned by a player
	public void deleteClaimsForPlayer(String playerName, boolean deleteCreativeClaims)
	{
		//make a list of the player's claims
		ArrayList<Claim> claimsToDelete = new ArrayList<Claim>();
		for(int i = 0; i < this.claims.size(); i++)
		{
			Claim claim = this.claims.get(i);
			if(claim.ownerName.equals(playerName) && (deleteCreativeClaims || !GriefPrevention.instance.creativeRulesApply(claim.getLesserBoundaryCorner())))
				claimsToDelete.add(claim);
		}
		
		//delete them one by one
		for(int i = 0; i < claimsToDelete.size(); i++)
		{
			claimsToDelete.get(i).removeSurfaceFluids(null);
			this.deleteClaim(claimsToDelete.get(i));
		}					
	}

	//tries to resize a claim
	//see CreateClaim() for details on return value
	public CreateClaimResult resizeClaim(Claim claim, int newx1, int newx2, int newy1, int newy2, int newz1, int newz2)
	{
		//remove old claim
		this.deleteClaim(claim);					
		
		//try to create this new claim, ignoring the original when checking for overlap
		CreateClaimResult result = this.createClaim(claim.getLesserBoundaryCorner().getWorld(), newx1, newx2, newy1, newy2, newz1, newz2, claim.ownerName, claim.parent);
		
		//if succeeded
		if(result.succeeded)
		{
			//copy permissions from old claim
			ArrayList<String> builders = new ArrayList<String>();
			ArrayList<String> containers = new ArrayList<String>();
			ArrayList<String> accessors = new ArrayList<String>();
			ArrayList<String> managers = new ArrayList<String>();
			claim.getPermissions(builders, containers, accessors, managers);
			
			for(int i = 0; i < builders.size(); i++)
				result.claim.setPermission(builders.get(i), ClaimPermission.Build);
			
			for(int i = 0; i < containers.size(); i++)
				result.claim.setPermission(containers.get(i), ClaimPermission.Inventory);
			
			for(int i = 0; i < accessors.size(); i++)
				result.claim.setPermission(accessors.get(i), ClaimPermission.Access);
			
			for(int i = 0; i < managers.size(); i++)
			{
				result.claim.managers.add(managers.get(i));
			}
			
			//copy subdivisions from old claim
			for(int i = 0; i < claim.children.size(); i++)
			{
				Claim subdivision = claim.children.get(i);
				subdivision.parent = result.claim;
				result.claim.children.add(subdivision);
			}
			
			//save those changes
			this.saveClaim(result.claim);
		}
		
		else
		{
			//put original claim back
			this.addClaim(claim);
		}
		
		return result;
	}
	
	private void loadMessages() 
	{
		Messages [] messageIDs = Messages.values();
		this.messages = new String[Messages.values().length];
		
		HashMap<String, CustomizableMessage> defaults = new HashMap<String, CustomizableMessage>();
		
		//initialize defaults
		this.addDefault(defaults, Messages.RespectingClaims, "Now respecting claims.", null);
		this.addDefault(defaults, Messages.IgnoringClaims, "Now ignoring claims.", null);
		this.addDefault(defaults, Messages.NoCreativeUnClaim, "You can't unclaim this land.  You can only make this claim larger or create additional claims.", null);
		this.addDefault(defaults, Messages.SuccessfulAbandon, "Claims abandoned.  You now have {0} available claim blocks.", "0: remaining blocks");
		this.addDefault(defaults, Messages.RestoreNatureActivate, "Ready to restore some nature!  Right click to restore nature, and use /BasicClaims to stop.", null);
		this.addDefault(defaults, Messages.RestoreNatureAggressiveActivate, "Aggressive mode activated.  Do NOT use this underneath anything you want to keep!  Right click to aggressively restore nature, and use /BasicClaims to stop.", null);
		this.addDefault(defaults, Messages.FillModeActive, "Fill mode activated with radius {0}.  Right click an area to fill.", "0: fill radius");
		this.addDefault(defaults, Messages.TransferClaimPermission, "That command requires the administrative claims permission.", null);
		this.addDefault(defaults, Messages.TransferClaimMissing, "There's no claim here.  Stand in the administrative claim you want to transfer.", null);
		this.addDefault(defaults, Messages.TransferClaimAdminOnly, "Only administrative claims may be transferred to a player.", null);
		this.addDefault(defaults, Messages.PlayerNotFound, "Player not found.", null);
		this.addDefault(defaults, Messages.TransferTopLevel, "Only top level claims (not subdivisions) may be transferred.  Stand outside of the subdivision and try again.", null);
		this.addDefault(defaults, Messages.TransferSuccess, "Claim transferred.", null);
		this.addDefault(defaults, Messages.TrustListNoClaim, "Stand inside the claim you're curious about.", null);
		this.addDefault(defaults, Messages.ClearPermsOwnerOnly, "Only the claim owner can clear all permissions.", null);
		this.addDefault(defaults, Messages.UntrustIndividualAllClaims, "Revoked {0}'s access to ALL your claims.  To set permissions for a single claim, stand inside it.", "0: untrusted player");
		this.addDefault(defaults, Messages.UntrustEveryoneAllClaims, "Cleared permissions in ALL your claims.  To set permissions for a single claim, stand inside it.", null);
		this.addDefault(defaults, Messages.NoPermissionTrust, "You don't have {0}'s permission to manage permissions here.", "0: claim owner's name");
		this.addDefault(defaults, Messages.ClearPermissionsOneClaim, "Cleared permissions in this claim.  To set permission for ALL your claims, stand outside them.", null);
		this.addDefault(defaults, Messages.UntrustIndividualSingleClaim, "Revoked {0}'s access to this claim.  To set permissions for a ALL your claims, stand outside them.", "0: untrusted player");
		this.addDefault(defaults, Messages.OnlySellBlocks, "Claim blocks may only be sold, not purchased.", null);
		this.addDefault(defaults, Messages.BlockPurchaseCost, "Each claim block costs {0}.  Your balance is {1}.", "0: cost of one block; 1: player's account balance");
		this.addDefault(defaults, Messages.ClaimBlockLimit, "You've reached your claim block limit.  You can't purchase more.", null);
		this.addDefault(defaults, Messages.InsufficientFunds, "You don't have enough money.  You need {0}, but you only have {1}.", "0: total cost; 1: player's account balance");
		this.addDefault(defaults, Messages.PurchaseConfirmation, "Withdrew {0} from your account.  You now have {1} available claim blocks.", "0: total cost; 1: remaining blocks");
		this.addDefault(defaults, Messages.OnlyPurchaseBlocks, "Claim blocks may only be purchased, not sold.", null);
		this.addDefault(defaults, Messages.BlockSaleValue, "Each claim block is worth {0}.  You have {1} available for sale.", "0: block value; 1: available blocks");
		this.addDefault(defaults, Messages.NotEnoughBlocksForSale, "You don't have that many claim blocks available for sale.", null);
		this.addDefault(defaults, Messages.BlockSaleConfirmation, "Deposited {0} in your account.  You now have {1} available claim blocks.", "0: amount deposited; 1: remaining blocks");
		this.addDefault(defaults, Messages.AdminClaimsMode, "Administrative claims mode active.  Any claims created will be free and editable by other administrators.", null);
		this.addDefault(defaults, Messages.BasicClaimsMode, "Returned to basic claim creation mode.", null);
		this.addDefault(defaults, Messages.SubdivisionMode, "Subdivision mode.  Use your shovel to create subdivisions in your existing claims.  Use /basicclaims to exit.", null);
		this.addDefault(defaults, Messages.SubdivisionDemo, "Want a demonstration?  http://tinyurl.com/7urdtue", null);
		this.addDefault(defaults, Messages.DeleteClaimMissing, "There's no claim here.", null);
		this.addDefault(defaults, Messages.DeletionSubdivisionWarning, "This claim includes subdivisions.  If you're sure you want to delete it, use /DeleteClaim again.", null);
		this.addDefault(defaults, Messages.DeleteSuccess, "Claim deleted.", null);
		this.addDefault(defaults, Messages.CantDeleteAdminClaim, "You don't have permission to delete administrative claims.", null);
		this.addDefault(defaults, Messages.DeleteAllSuccess, "Deleted all of {0}'s claims.", "0: owner's name");
		this.addDefault(defaults, Messages.NoDeletePermission, "You don't have permission to delete claims.", null);
		this.addDefault(defaults, Messages.AllAdminDeleted, "Deleted all administrative claims.", null);
		this.addDefault(defaults, Messages.AdjustBlocksSuccess, "Adjusted {0}'s bonus claim blocks by {1}.  New total bonus blocks: {2}.", "0: player; 1: adjustment; 2: new total");
		this.addDefault(defaults, Messages.NotTrappedHere, "You can build here.  Save yourself.", null);
		this.addDefault(defaults, Messages.TrappedOnCooldown, "You used /trapped within the last {0} hours.  You have to wait about {1} more minutes before using it again.", "0: default cooldown hours; 1: remaining minutes");
		this.addDefault(defaults, Messages.RescuePending, "If you stay put for 10 seconds, you'll be teleported out.  Please wait.", null);
		this.addDefault(defaults, Messages.NonSiegeWorld, "Siege is disabled here.", null);
		this.addDefault(defaults, Messages.AlreadySieging, "You're already involved in a siege.", null);
		this.addDefault(defaults, Messages.AlreadyUnderSiegePlayer, "{0} is already under siege.  Join the party!", "0: defending player");
		this.addDefault(defaults, Messages.NotSiegableThere, "{0} isn't protected there.", "0: defending player");
		this.addDefault(defaults, Messages.SiegeTooFarAway, "You're too far away to siege.", null);
		this.addDefault(defaults, Messages.NoSiegeDefenseless, "That player is defenseless.  Go pick on somebody else.", null);
		this.addDefault(defaults, Messages.AlreadyUnderSiegeArea, "That area is already under siege.  Join the party!", null);
		this.addDefault(defaults, Messages.NoSiegeAdminClaim, "Siege is disabled in this area.", null);
		this.addDefault(defaults, Messages.SiegeOnCooldown, "You're still on siege cooldown for this defender or claim.  Find another victim.", null);
		this.addDefault(defaults, Messages.SiegeAlert, "You're under siege!  If you log out now, you will die.  You must defeat {0}, wait for him to give up, or escape.", "0: attacker name");
		this.addDefault(defaults, Messages.SiegeConfirmed, "The siege has begun!  If you log out now, you will die.  You must defeat {0}, chase him away, or admit defeat and walk away.", "0: defender name");
		this.addDefault(defaults, Messages.AbandonClaimMissing, "Stand in the claim you want to delete, or consider /AbandonAllClaims.", null);
		this.addDefault(defaults, Messages.NotYourClaim, "This isn't your claim.", null);
		this.addDefault(defaults, Messages.DeleteTopLevelClaim, "To delete a subdivision, stand inside it.  Otherwise, use /AbandonTopLevelClaim to delete this claim and all subdivisions.", null);		
		this.addDefault(defaults, Messages.AbandonSuccess, "Claim abandoned.  You now have {0} available claim blocks.", "0: remaining claim blocks");
		this.addDefault(defaults, Messages.CantGrantThatPermission, "You can't grant a permission you don't have yourself.", null);
		this.addDefault(defaults, Messages.GrantPermissionNoClaim, "Stand inside the claim where you want to grant permission.", null);
		this.addDefault(defaults, Messages.GrantPermissionConfirmation, "Granted {0} permission to {1} {2}.", "0: target player; 1: permission description; 2: scope (changed claims)");
		this.addDefault(defaults, Messages.ManageUniversalPermissionsInstruction, "To manage permissions for ALL your claims, stand outside them.", null);
		this.addDefault(defaults, Messages.ManageOneClaimPermissionsInstruction, "To manage permissions for a specific claim, stand inside it.", null);
		this.addDefault(defaults, Messages.CollectivePublic, "the public", "as in 'granted the public permission to...'");
		this.addDefault(defaults, Messages.BuildPermission, "build", null);
		this.addDefault(defaults, Messages.ContainersPermission, "access containers and animals", null);
		this.addDefault(defaults, Messages.AccessPermission, "use buttons and levers", null);
		this.addDefault(defaults, Messages.PermissionsPermission, "manage permissions", null);
		this.addDefault(defaults, Messages.LocationCurrentClaim, "in this claim", null);
		this.addDefault(defaults, Messages.LocationAllClaims, "in all your claims", null);
		this.addDefault(defaults, Messages.PvPImmunityStart, "You're protected from attack by other players as long as your inventory is empty.", null);
		this.addDefault(defaults, Messages.SiegeNoDrop, "You can't give away items while involved in a siege.", null);
		this.addDefault(defaults, Messages.DonateItemsInstruction, "To give away the item(s) in your hand, left-click the chest again.", null);
		this.addDefault(defaults, Messages.ChestFull, "This chest is full.", null);
		this.addDefault(defaults, Messages.DonationSuccess, "Item(s) transferred to chest!", null);
		this.addDefault(defaults, Messages.PlayerTooCloseForFire, "You can't start a fire this close to {0}.", "0: other player's name");
		this.addDefault(defaults, Messages.TooDeepToClaim, "This chest can't be protected because it's too deep underground.  Consider moving it.", null);
		this.addDefault(defaults, Messages.ChestClaimConfirmation, "This chest is protected.", null);
		this.addDefault(defaults, Messages.AutomaticClaimNotification, "This chest and nearby blocks are protected from breakage and theft.  The temporary gold and glowstone blocks mark the protected area.  To toggle them on and off, right-click with a stick.", null);
		this.addDefault(defaults, Messages.TrustCommandAdvertisement, "Use the /trust command to grant other players access.", null);
		this.addDefault(defaults, Messages.GoldenShovelAdvertisement, "To claim more land, you need a golden shovel.  When you equip one, you'll get more information.", null);
		this.addDefault(defaults, Messages.UnprotectedChestWarning, "This chest is NOT protected.  Consider expanding an existing claim or creating a new one.", null);
		this.addDefault(defaults, Messages.ThatPlayerPvPImmune, "You can't injure defenseless players.", null);
		this.addDefault(defaults, Messages.CantFightWhileImmune, "You can't fight someone while you're protected from PvP.", null);
		this.addDefault(defaults, Messages.NoDamageClaimedEntity, "That belongs to {0}.", "0: owner name");
		this.addDefault(defaults, Messages.ShovelBasicClaimMode, "Shovel returned to basic claims mode.", null);
		this.addDefault(defaults, Messages.RemainingBlocks, "You may claim up to {0} more blocks.", "0: remaining blocks");
		this.addDefault(defaults, Messages.CreativeBasicsDemoAdvertisement, "Want a demonstration?  http://tinyurl.com/c7bajb8", null);
		this.addDefault(defaults, Messages.SurvivalBasicsDemoAdvertisement, "Want a demonstration?  http://tinyurl.com/6nkwegj", null);
		this.addDefault(defaults, Messages.TrappedChatKeyword, "trapped", "When mentioned in chat, players get information about the /trapped command.");
		this.addDefault(defaults, Messages.TrappedInstructions, "Are you trapped in someone's claim?  Consider the /trapped command.", null);
		this.addDefault(defaults, Messages.PvPNoDrop, "You can't drop items while in PvP combat.", null);
		this.addDefault(defaults, Messages.SiegeNoTeleport, "You can't teleport out of a besieged area.", null);
		this.addDefault(defaults, Messages.BesiegedNoTeleport, "You can't teleport into a besieged area.", null);
		this.addDefault(defaults, Messages.SiegeNoContainers, "You can't access containers while involved in a siege.", null);
		this.addDefault(defaults, Messages.PvPNoContainers, "You can't access containers during PvP combat.", null);
		this.addDefault(defaults, Messages.PvPImmunityEnd, "Now you can fight with other players.", null);
		this.addDefault(defaults, Messages.NoBedPermission, "{0} hasn't given you permission to sleep here.", "0: claim owner");
		this.addDefault(defaults, Messages.NoWildernessBuckets, "You may only dump buckets inside your claim(s) or underground.", null);
		this.addDefault(defaults, Messages.NoLavaNearOtherPlayer, "You can't place lava this close to {0}.", "0: nearby player");
		this.addDefault(defaults, Messages.TooFarAway, "That's too far away.", null);
		this.addDefault(defaults, Messages.BlockNotClaimed, "No one has claimed this block.", null);
		this.addDefault(defaults, Messages.BlockClaimed, "That block has been claimed by {0}.", "0: claim owner");
		this.addDefault(defaults, Messages.SiegeNoShovel, "You can't use your shovel tool while involved in a siege.", null);
		this.addDefault(defaults, Messages.RestoreNaturePlayerInChunk, "Unable to restore.  {0} is in that chunk.", "0: nearby player");
		this.addDefault(defaults, Messages.NoCreateClaimPermission, "You don't have permission to claim land.", null);
		this.addDefault(defaults, Messages.ResizeClaimTooSmall, "This new size would be too small.  Claims must be at least {0} x {0}.", "0: minimum claim size");
		this.addDefault(defaults, Messages.ResizeNeedMoreBlocks, "You don't have enough blocks for this size.  You need {0} more.", "0: how many needed");
		this.addDefault(defaults, Messages.ClaimResizeSuccess, "Claim resized.  You now have {0} available claim blocks.", "0: remaining blocks");
		this.addDefault(defaults, Messages.ResizeFailOverlap, "Can't resize here because it would overlap another nearby claim.", null);
		this.addDefault(defaults, Messages.ResizeStart, "Resizing claim.  Use your shovel again at the new location for this corner.", null);
		this.addDefault(defaults, Messages.ResizeFailOverlapSubdivision, "You can't create a subdivision here because it would overlap another subdivision.  Consider /abandonclaim to delete it, or use your shovel at a corner to resize it.", null);
		this.addDefault(defaults, Messages.SubdivisionStart, "Subdivision corner set!  Use your shovel at the location for the opposite corner of this new subdivision.", null);
		this.addDefault(defaults, Messages.CreateSubdivisionOverlap, "Your selected area overlaps another subdivision.", null);
		this.addDefault(defaults, Messages.SubdivisionSuccess, "Subdivision created!  Use /trust to share it with friends.", null);
		this.addDefault(defaults, Messages.CreateClaimFailOverlap, "You can't create a claim here because it would overlap your other claim.  Use /abandonclaim to delete it, or use your shovel at a corner to resize it.", null);
		this.addDefault(defaults, Messages.CreateClaimFailOverlapOtherPlayer, "You can't create a claim here because it would overlap {0}'s claim.", "0: other claim owner");
		this.addDefault(defaults, Messages.ClaimsDisabledWorld, "Land claims are disabled in this world.", null);
		this.addDefault(defaults, Messages.ClaimStart, "Claim corner set!  Use the shovel again at the opposite corner to claim a rectangle of land.  To cancel, put your shovel away.", null);
		this.addDefault(defaults, Messages.NewClaimTooSmall, "This claim would be too small.  Any claim must be at least {0} x {0}.", "0: minimum claim size");
		this.addDefault(defaults, Messages.CreateClaimInsufficientBlocks, "You don't have enough blocks to claim that entire area.  You need {0} more blocks.", "0: additional blocks needed");
		this.addDefault(defaults, Messages.AbandonClaimAdvertisement, "To delete another claim and free up some blocks, use /AbandonClaim.", null);
		this.addDefault(defaults, Messages.CreateClaimFailOverlapShort, "Your selected area overlaps an existing claim.", null);
		this.addDefault(defaults, Messages.CreateClaimSuccess, "Claim created!  Use /trust to share it with friends.", null);
		this.addDefault(defaults, Messages.SiegeWinDoorsOpen, "Congratulations!  Buttons and levers are temporarily unlocked (five minutes).", null);
		this.addDefault(defaults, Messages.RescueAbortedMoved, "You moved!  Rescue cancelled.", null);
		this.addDefault(defaults, Messages.SiegeDoorsLockedEjection, "Looting time is up!  Ejected from the claim.", null);
		this.addDefault(defaults, Messages.NoModifyDuringSiege, "Claims can't be modified while under siege.", null);
		this.addDefault(defaults, Messages.OnlyOwnersModifyClaims, "Only {0} can modify this claim.", "0: owner name");
		this.addDefault(defaults, Messages.NoBuildUnderSiege, "This claim is under siege by {0}.  No one can build here.", "0: attacker name");
		this.addDefault(defaults, Messages.NoBuildPvP, "You can't build in claims during PvP combat.", null);
		this.addDefault(defaults, Messages.NoBuildPermission, "You don't have {0}'s permission to build here.", "0: owner name");
		this.addDefault(defaults, Messages.NonSiegeMaterial, "That material is too tough to break.", null);
		this.addDefault(defaults, Messages.NoOwnerBuildUnderSiege, "You can't make changes while under siege.", null);
		this.addDefault(defaults, Messages.NoAccessPermission, "You don't have {0}'s permission to use that.", "0: owner name.  access permission controls buttons, levers, and beds");
		this.addDefault(defaults, Messages.NoContainersSiege, "This claim is under siege by {0}.  No one can access containers here right now.", "0: attacker name");
		this.addDefault(defaults, Messages.NoContainersPermission, "You don't have {0}'s permission to use that.", "0: owner's name.  containers also include crafting blocks");
		this.addDefault(defaults, Messages.OwnerNameForAdminClaims, "an administrator", "as in 'You don't have an administrator's permission to build here.'");
		this.addDefault(defaults, Messages.ClaimTooSmallForEntities, "This claim isn't big enough for that.  Try enlarging it.", null);
		this.addDefault(defaults, Messages.TooManyEntitiesInClaim, "This claim has too many entities already.  Try enlarging the claim or removing some animals, monsters, paintings, or minecarts.", null);
		this.addDefault(defaults, Messages.YouHaveNoClaims, "You don't have any land claims.", null);
		this.addDefault(defaults, Messages.ConfirmFluidRemoval, "Abandoning this claim will remove all your lava and water.  If you're sure, use /AbandonClaim again.", null);
		this.addDefault(defaults, Messages.AutoBanNotify, "Auto-banned {0}({1}).  See logs for details.", null);
		this.addDefault(defaults, Messages.AdjustGroupBlocksSuccess, "Adjusted bonus claim blocks for players with the {0} permission by {1}.  New total: {2}.", "0: permission; 1: adjustment amount; 2: new total bonus");
		this.addDefault(defaults, Messages.InvalidPermissionID, "Please specify a player name, or a permission in [brackets].", null);
		this.addDefault(defaults, Messages.UntrustOwnerOnly, "Only {0} can revoke permissions here.", "0: claim owner's name");
		this.addDefault(defaults, Messages.HowToClaimRegex, "(^|.*\\W)how\\W.*\\Wclaim(\\W.*|$)", "This is a Java Regular Expression.  Look it up before editing!  It's used to tell players about the demo video when they ask how to claim land.");	
		
		//load the config file
		FileConfiguration config = YamlConfiguration.loadConfiguration(new File(messagesFilePath));
		
		//for each message ID
		for(int i = 0; i < messageIDs.length; i++)
		{
			//get default for this message
			Messages messageID = messageIDs[i];
			CustomizableMessage messageData = defaults.get(messageID.name());
			
			//if default is missing, log an error and use some fake data for now so that the plugin can run
			if(messageData == null)
			{
				GriefPrevention.AddLogEntry("Missing message for " + messageID.name() + ".  Please contact the developer.");
				messageData = new CustomizableMessage(messageID, "Missing message!  ID: " + messageID.name() + ".  Please contact a server admin.", null);
			}
			
			//read the message from the file, use default if necessary
			this.messages[messageID.ordinal()] = config.getString("Messages." + messageID.name() + ".Text", messageData.text);
			config.set("Messages." + messageID.name() + ".Text", this.messages[messageID.ordinal()]);
			
			if(messageData.notes != null)
			{
				messageData.notes = config.getString("Messages." + messageID.name() + ".Notes", messageData.notes);
				config.set("Messages." + messageID.name() + ".Notes", messageData.notes);
			}
		}
		
		//save any changes
		try
		{
			config.save(DataStore.messagesFilePath);
		}
		catch(IOException exception)
		{
			GriefPrevention.AddLogEntry("Unable to write to the configuration file at \"" + DataStore.messagesFilePath + "\"");
		}
		
		defaults.clear();
		System.gc();				
	}

	private void addDefault(HashMap<String, CustomizableMessage> defaults,
			Messages id, String text, String notes)
	{
		CustomizableMessage message = new CustomizableMessage(id, text, notes);
		defaults.put(id.name(), message);		
	}

	public String getMessage(Messages messageID, String... args)
	{
		String message = messages[messageID.ordinal()];
		
		for(int i = 0; i < args.length; i++)
		{
			String param = args[i];
			message = message.replace("{" + i + "}", param);
		}
		
		return message;
		
	}
}