/*
 * Copyright (c) 2014 Tom Parker <thpr@users.sourceforge.net>
 * 
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 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 Lesser General Public License for more
 * details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */
package plugin.lsttokens.variable;

import java.util.Set;

import pcgen.base.formula.base.LegalScope;
import pcgen.base.util.FormatManager;
import pcgen.cdom.base.Constants;
import pcgen.cdom.content.DatasetVariable;
import pcgen.output.channel.ChannelUtilities;
import pcgen.rules.context.LoadContext;
import pcgen.rules.context.VariableContext;
import pcgen.rules.persistence.token.AbstractNonEmptyToken;
import pcgen.rules.persistence.token.CDOMPrimaryToken;
import pcgen.rules.persistence.token.ParseResult;

public class ChannelToken extends AbstractNonEmptyToken<DatasetVariable>
		implements CDOMPrimaryToken<DatasetVariable>
{

	@Override
	public String getTokenName()
	{
		return "CHANNEL";
	}

	@Override
	protected ParseResult parseNonEmptyToken(LoadContext context,
		DatasetVariable dv, String value)
	{
		int pipeLoc = value.indexOf(Constants.PIPE);
		if (pipeLoc == -1)
		{
			return new ParseResult.Fail(getTokenName()
				+ " expected 2 pipe delimited arguments, found no pipe: "
				+ value);
		}
		if (pipeLoc != value.lastIndexOf(Constants.PIPE))
		{
			return new ParseResult.Fail(getTokenName()
				+ " expected only 2 pipe delimited arguments, found: " + value);
		}
		String fullscope = value.substring(0, pipeLoc);
		String fvName = value.substring(pipeLoc + 1);
		String format;
		String varName;
		int equalLoc = fvName.indexOf('=');
		if (equalLoc != fvName.lastIndexOf('='))
		{
			return new ParseResult.Fail(getTokenName()
				+ " expected only 2 equal delimited arguments, found: " + value);
		}
		if (equalLoc == -1)
		{
			//Defaults to NUMBER
			format = "NUMBER";
			varName = fvName;
		}
		else
		{
			format = fvName.substring(0, equalLoc);
			varName = fvName.substring(equalLoc + 1);
		}
		if (dv.getDisplayName() != null)
		{
			return new ParseResult.Fail(getTokenName()
				+ " must be the first token on the line");
		}

		VariableContext varContext = context.getVariableContext();
		FormatManager<?> formatManager;
		try
		{
			formatManager =
					context.getReferenceContext().getFormatManager(format);
		}
		catch (IllegalArgumentException e)
		{
			return new ParseResult.Fail(getTokenName()
				+ " does not support format " + format + ", found in " + value
				+ " due to " + e.getMessage());
		}
		LegalScope lvs;
		if ("GLOBAL".equals(fullscope))
		{
			lvs = context.getActiveScope().getLegalScope();
		}
		else
		{
			lvs = varContext.getScope(fullscope);
		}

		if (!DatasetVariable.isLegalName(varName))
		{
			return new ParseResult.Fail(varName
				+ " is not a valid channel name");
		}
		String channelName = ChannelUtilities.createVarName(varName);
		boolean legal =
				varContext.assertLegalVariableID(lvs, formatManager, channelName);
		if (!legal)
		{
			Set<LegalScope> known = varContext.getKnownLegalScopes(varName);
			StringBuilder sb = new StringBuilder();
			for (LegalScope v : known)
			{
				sb.append(v.getName());
				sb.append(", ");
			}
			return new ParseResult.Fail(getTokenName()
				+ " found a var defined in incompatible variable scopes: "
				+ varName + " was requested in " + fullscope
				+ " but was previously in " + sb.toString(), context);
		}
		dv.setName(channelName);
		dv.setFormat(format);
		dv.setScopeName(fullscope);
		return ParseResult.SUCCESS;
	}

	@Override
	public String[] unparse(LoadContext context, DatasetVariable dv)
	{
		String varName = dv.getKeyName();
		if (!varName.startsWith("CHANNEL*"))
		{
			//Variable
			return null;
		}
		String scope = dv.getScopeName();
		if (scope == null || scope.equals("Global Variables"))
		{
			//Global channel
			scope = "GLOBAL";
		}
		String format = dv.getFormat();
		if (format == null)
		{
			//Not a valid object
			return null;
		}
		StringBuilder sb = new StringBuilder();
		sb.append(scope);
		sb.append(Constants.PIPE);
		if (!format.equals("NUMBER"))
		{
			sb.append(format);
			sb.append('=');
		}
		//Take off CHANNEL*
		sb.append(varName.substring(8));
		return new String[]{sb.toString()};
	}

	@Override
	public Class<DatasetVariable> getTokenClass()
	{
		return DatasetVariable.class;
	}

}