package org.bukkit.command.defaults;

import com.google.common.collect.ImmutableList;
import org.apache.commons.lang.Validate;
import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.command.CommandSender;
import org.bukkit.plugin.Plugin;
import org.bukkit.plugin.PluginDescriptionFile;
import org.bukkit.util.StringUtil;

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

public class VersionCommand extends BukkitCommand
{
	public VersionCommand(String name)
	{
		super(name);

		this.description = "Gets the version of this server including any plugins in use";
		this.usageMessage = "/version [plugin name]";
		this.setPermission("bukkit.command.version");
		this.setAliases(Arrays.asList("ver", "about"));
	}

	@Override
	public boolean execute(CommandSender sender, String currentAlias, String[] args)
	{
		if(!testPermission(sender)) return true;

		if(args.length == 0)
		{
			sender.sendMessage("This server is running " + Bukkit.getName() + " version " + Bukkit.getVersion() + " (Implementing API version " + Bukkit.getBukkitVersion() + ")");
		}
		else
		{
			StringBuilder name = new StringBuilder();

			for(String arg : args)
			{
				if(name.length() > 0)
				{
					name.append(' ');
				}

				name.append(arg);
			}

			String pluginName = name.toString();
			Plugin exactPlugin = Bukkit.getPluginManager().getPlugin(pluginName);
			if(exactPlugin != null)
			{
				describeToSender(exactPlugin, sender);
				return true;
			}

			boolean found = false;
			pluginName = pluginName.toLowerCase();
			for(Plugin plugin : Bukkit.getPluginManager().getPlugins())
			{
				if(plugin.getName().toLowerCase().contains(pluginName))
				{
					describeToSender(plugin, sender);
					found = true;
				}
			}

			if(!found)
			{
				sender.sendMessage("This server is not running any plugin by that name.");
				sender.sendMessage("Use /plugins to get a list of plugins.");
			}
		}
		return true;
	}

	private void describeToSender(Plugin plugin, CommandSender sender)
	{
		PluginDescriptionFile desc = plugin.getDescription();
		sender.sendMessage(ChatColor.GREEN + desc.getName() + ChatColor.WHITE + " version " + ChatColor.GREEN + desc.getVersion());

		if(desc.getDescription() != null)
		{
			sender.sendMessage(desc.getDescription());
		}

		if(desc.getWebsite() != null)
		{
			sender.sendMessage("Website: " + ChatColor.GREEN + desc.getWebsite());
		}

		if(!desc.getAuthors().isEmpty())
		{
			if(desc.getAuthors().size() == 1)
			{
				sender.sendMessage("Author: " + getAuthors(desc));
			}
			else
			{
				sender.sendMessage("Authors: " + getAuthors(desc));
			}
		}
	}

	private String getAuthors(final PluginDescriptionFile desc)
	{
		StringBuilder result = new StringBuilder();
		List<String> authors = desc.getAuthors();

		for(int i = 0; i < authors.size(); i++)
		{
			if(result.length() > 0)
			{
				result.append(ChatColor.WHITE);

				if(i < authors.size() - 1)
				{
					result.append(", ");
				}
				else
				{
					result.append(" and ");
				}
			}

			result.append(ChatColor.GREEN);
			result.append(authors.get(i));
		}

		return result.toString();
	}

	@Override
	public List<String> tabComplete(CommandSender sender, String alias, String[] args)
	{
		Validate.notNull(sender, "Sender cannot be null");
		Validate.notNull(args, "Arguments cannot be null");
		Validate.notNull(alias, "Alias cannot be null");

		if(args.length == 1)
		{
			List<String> completions = new ArrayList<String>();
			String toComplete = args[0].toLowerCase();
			for(Plugin plugin : Bukkit.getPluginManager().getPlugins())
			{
				if(StringUtil.startsWithIgnoreCase(plugin.getName(), toComplete))
				{
					completions.add(plugin.getName());
				}
			}
			return completions;
		}
		return ImmutableList.of();
	}
}