TF-EssentialsX/Essentials/src/com/earth2me/essentials/register/payment/Methods.java

package com.earth2me.essentials.register.payment;

import java.util.HashSet;
import java.util.Set;
import org.bukkit.plugin.Plugin;
import org.bukkit.plugin.PluginManager;


/**
 * The
 * <code>Methods</code> initializes Methods that utilize the Method interface based on a "first come, first served"
 * basis.
 *
 * Allowing you to check whether a payment method exists or not.
 *
 * Methods also allows you to set a preferred method of payment before it captures payment plugins in the initialization
 * process.
 *
 * in
 * <code>bukkit.yml</code>: <blockquote><pre>
 *  economy:
 *      preferred: "iConomy"
 * </pre></blockquote>
 *
 * @author: Nijikokun <nijikokun@shortmail.com> (@nijikokun) @copyright: Copyright (C) 2011 @license: AOL license
 * <http://aol.nexua.org>
 */
public class Methods
{
	private static String version = null;
	private static boolean self = false;
	private static Method Method = null;
	private static String preferred = "";
	private static Set<Method> Methods = new HashSet<Method>();
	private static Set<String> Dependencies = new HashSet<String>();
	private static Set<Method> Attachables = new HashSet<Method>();

	static
	{
		_init();
	}

	/**
	 * Implement all methods along with their respective name & class.
	 */
	private static void _init()
	{
		addMethod("iConomy", new com.earth2me.essentials.register.payment.methods.iCo6());
		addMethod("iConomy", new com.earth2me.essentials.register.payment.methods.iCo5());
		addMethod("BOSEconomy", new com.earth2me.essentials.register.payment.methods.BOSE7());
		addMethod("Currency", new com.earth2me.essentials.register.payment.methods.MCUR());
		Dependencies.add("MultiCurrency");
		addMethod("Vault", new com.earth2me.essentials.register.payment.methods.VaultEco());
	}

	/**
	 * Used by the plugin to setup version
	 *
	 * @param v version
	 */
	public static void setVersion(String v)
	{
		version = v;
	}

	/**
	 * Use to reset methods during disable
	 */
	public static void reset()
	{
		version = null;
		self = false;
		Method = null;
		preferred = "";
		Attachables.clear();
	}

	/**
	 * Use to get version of Register plugin
	 *
	 * @return version
	 */
	public static String getVersion()
	{
		return version;
	}

	/**
	 * Returns an array of payment method names that have been loaded through the
	 * <code>_init</code> method.
	 *
	 * @return
	 * <code>Set<String></code> - Array of payment methods that are loaded.
	 * @see #setMethod(org.bukkit.plugin.Plugin)
	 */
	public static Set<String> getDependencies()
	{
		return Dependencies;
	}

	/**
	 * Interprets Plugin class data to verify whether it is compatible with an existing payment method to use for
	 * payments and other various economic activity.
	 *
	 * @param plugin Plugin data from bukkit, Internal Class file.
	 * @return Method <em>or</em> Null
	 */
	public static Method createMethod(Plugin plugin)
	{
		for (Method method : Methods)
		{
			if (method.isCompatible(plugin))
			{
				method.setPlugin(plugin);
				return method;
			}
		}

		return null;
	}

	private static void addMethod(String name, Method method)
	{
		Dependencies.add(name);
		Methods.add(method);
	}

	/**
	 * Verifies if Register has set a payment method for usage yet.
	 *
	 * @return
	 * <code>boolean</code>
	 * @see #setMethod(org.bukkit.plugin.Plugin)
	 * @see #checkDisabled(org.bukkit.plugin.Plugin)
	 */
	public static boolean hasMethod()
	{
		return (Method != null);
	}

	/**
	 * Checks Plugin Class against a multitude of checks to verify it's usability as a payment method.
	 *
	 * @param <code>PluginManager</code> the plugin manager for the server
	 * @return
	 * <code>boolean</code> True on success, False on failure.
	 */
	public static boolean setMethod(PluginManager manager)
	{
		if (hasMethod())
		{
			return true;
		}

		if (self)
		{
			self = false;
			return false;
		}

		int count = 0;
		boolean match = false;
		Plugin plugin = null;

		for (String name : getDependencies())
		{
			if (hasMethod())
			{
				break;
			}

			plugin = manager.getPlugin(name);
			if (plugin == null || !plugin.isEnabled())
			{
				continue;
			}

			Method current = createMethod(plugin);
			if (current == null)
			{
				continue;
			}

			if (preferred.isEmpty())
			{
				Method = current;
			}
			else
			{
				Attachables.add(current);
			}
		}

		if (!preferred.isEmpty())
		{
			do
			{
				if (hasMethod())
				{
					match = true;
				}
				else
				{
					for (Method attached : Attachables)
					{
						if (attached == null)
						{
							continue;
						}

						if (hasMethod())
						{
							match = true;
							break;
						}

						if (preferred.isEmpty())
						{
							Method = attached;
						}

						if (count == 0)
						{
							if (preferred.equalsIgnoreCase(attached.getName()))
							{
								Method = attached;
							}
							else
							{
								Method = attached;
							}
						}
					}

					count++;
				}
			}
			while (!match);
		}

		return hasMethod();
	}

	/**
	 * Sets the preferred economy
	 *
	 * @return
	 * <code>boolean</code>
	 */
	public static boolean setPreferred(String check)
	{
		if (getDependencies().contains(check))
		{
			preferred = check;
			return true;
		}

		return false;
	}

	/**
	 * Grab the existing and initialized (hopefully) Method Class.
	 *
	 * @return
	 * <code>Method</code> <em>or</em>
	 * <code>Null</code>
	 */
	public static Method getMethod()
	{
		return Method;
	}

	/**
	 * Verify is a plugin is disabled, only does this if we there is an existing payment method initialized in Register.
	 *
	 * @param method Plugin data from bukkit, Internal Class file.
	 * @return
	 * <code>boolean</code>
	 */
	public static boolean checkDisabled(Plugin method)
	{
		if (!hasMethod())
		{
			return true;
		}

		if (Method.isCompatible(method))
		{
			Method = null;
		}

		return (Method == null);
	}
}