/*

   Derby - Class org.apache.derbyBuild.propertyconfig

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package org.apache.derbyBuild;
import java.util.Properties;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.File;

import java.util.StringTokenizer;
import java.util.Properties;
import java.util.Enumeration;


/**
 * 
 * Usage: 
 * java propertyConfig <master file> <config> <output file>
 * <B> e.g., java propertyConfig dbms.properties cloudsync
 * cloudsync.dbms.properties 
 *
 * <P>
 * This program takes a master property file, and using the configuration
 * specification, generate an output file that only contains the properties
 * for that particular configuration.
 *
 * <P>
 * For the different types of legitamite configurations, please see
 * org.apache.derby.modules.properties
 *
 * <P>
 * PropertySplitter will look at cloudscape.config.<tag> to see which
 * configuration a particular module belongs to.
 * <B>E.g., cloudscape.config.dataComm.listen=cloudtarget,cloudsync
 * <B>this means all properties associated with dataComm.listen will be
 * in the output properties file only if we are generating for the cloudsync or
 * cloudtarget configuration.  They will not be in the output properties file
 * if we are generating for the cloud or cloudscape configuration.
 * 
 */

public class propertyconfig {

	public static final String header =
		"######## This is a generated file, do not edit.\n" +
		"#\n# This file is generated as by propertyConfig\n" +
		"#\n";

	public static final String footer =
		"\n######## This is a generated file, do not edit.\n";

	public static void main(String[] args) throws IOException
	{
		if (args.length != 3)
			printUsageAndExit();

		File masterfile = new File(args[0]);
		File outputfile = new File(args[2]);

		if (!masterfile.exists())
			printUsageAndExit();

		// OK, got the input cleared up, now do the processing
		Properties masterProp = new Properties();
		FileInputStream is = new FileInputStream(masterfile);

		try
		{
			masterProp.load(is);
		}
		finally
		{
			if (is != null)
				is.close();
		}

		process(masterProp, args[1], outputfile);
	}

	/**
	 * For each module with a particular tag in derby.module.<tag>, see if
	 * there is any configuration restriction.  If there is no
	 * cloudscape.config.<tag> property, then this module should be present in
	 * all configurations.  If there is a cloudscape.config.<tag>, then this
	 * module should only be present in the configurations listed.
	 *
	 * <br>If this module should be present or this configuration, then gather
	 * up all the properties belong to this module and send it to the output
	 * file.
	 *
	 */
	private static void process(Properties moduleList, String config, 
								File outputfile)
					throws IOException
	{
		Properties outputProp = new Properties();

		// copy this code from
		// org.apache.derby.impl.services.monitor.BaseMonitor 
		//
		for (Enumeration e = moduleList.propertyNames(); e.hasMoreElements(); ) 
		{
			String key = (String) e.nextElement();
			if (key.startsWith("derby.module."))
			{
				String tag = key.substring("derby.module.".length());

				// Check to see if it has any configuration requirements 
				String configKey = "cloudscape.config.".concat(tag);
				String configProp = moduleList.getProperty(configKey);
				
				boolean match = false;

				if (configProp != null) 
				{
					StringTokenizer st = new StringTokenizer(configProp, ",");
					while(st.hasMoreTokens()) 
					{

						String s = st.nextToken().trim();

						// if config spec says all, it should not have other
						// configurations
						if (s.equalsIgnoreCase("all") &&
							!configProp.trim().equals("all"))
						{
							System.out.println("illegal config specification "
											   + key);
							System.exit(3);
						}

						// if config spec says none, it should not have other
						// configurations
						if (s.equalsIgnoreCase("none") &&
							!configProp.trim().equals("none"))
						{
							System.out.println("illegal config specification "
											   + key);
							System.exit(4);
						}

						if (s.equalsIgnoreCase(config) ||
							s.equalsIgnoreCase("all"))
						{
							match = true;
							break;
						}
					}
				}
				else
				{
					// no config property, this module goes to all configs
					System.out.println("Need config specification for " + key);
					System.exit(2);
				}

				if (match)
				{
					// gather up all relavant properties and put it in
					// outputProp

					// derby.module.<tag>
					outputProp.put(key, moduleList.getProperty(key));

					// don't output cloudscape.config.<tag>
					// that line only has meaning to this program

					// derby.env.classes.<tag>
					String envKey = "derby.env.classes.".concat(tag);
					if (moduleList.getProperty(envKey) != null)
						outputProp.put(envKey, moduleList.getProperty(envKey));

					// derby.env.jdk.<tag>
					// 
					// some of the configs only support one java env.  Some modules
					// have alternate implementation for running on java1 and
					// java2 platforms.  If we get rid of, say, the java2
					// implementation, then the monitor won't load the java1
					// implementation if that module specifies that it should
					// only be loaded in a java1 environment.  The result is
					// that some critical modules will be missing and the
					// database won't boot.
					//
					// the convention is, for modules that have both java1 and
					// java2 implementation, they must named the module as
					// derby.env.jdk.<name>J1 or
					// derby.env.jdk.<name>J2
					// in other words, the <tag> must end with J1 or J2.
					//
					// If a config only use one of the two implementation, then
					// this program will not put the one env.jdk line to the
					// output properties.  As a result, this one implementation
					// will be loaded when run in any environment.
					//
					// This does not apply to any module that only has one
					// implementation that runs on a specific jdk environment.
					//
					//derby.env.jdk.<tag>
					envKey = "derby.env.jdk.".concat(tag);

					if (moduleList.getProperty(envKey) != null)
					{
						// by default keep the jdk env specification with the
						// config  
						boolean saveEnvKey = true;

						// figure out if this is a tag of the form <name>J1 or
						// <name>J2.
						if (tag.endsWith("J1") || tag.endsWith("J2"))
						{
							// ok, this is a module with alternate
							// implementation for java 1 and java 2.  If this
							// config ditches one of them, then do not output
							// the env line
							int length = tag.length() - 2;
							String alternateTag = tag.substring(0, length);
							
							if (tag.endsWith("J1"))
								alternateTag += "J2";
							else
								alternateTag += "J1";

							// see if 
							// 1) this module has an alternate impl for the 
							// other jdk and 
							// 2) this config is not going to pick it up.
							//
							
							String alternateImplKey = 
								"derby.module."+ alternateTag;
							String alternateJDKEnv = 
								"derby.env.jdk."+ alternateTag;
							String alternateImplConfigKey =
								"cloudscape.config."+alternateTag;

							// if any of of these are not present, then we
							// don't have a problem because either there is no
							// alternate implementation, or the alternate
							// implementation is not based on jdk, or the
							// alternate jdk based implemenation will also be
							// present in this configuration

							if ((moduleList.getProperty(alternateImplKey) != null) &&
								(moduleList.getProperty(alternateJDKEnv) != null) && 
								(moduleList.getProperty(alternateImplConfigKey) != null))
							{
								// there is an alternate impl that is jdk based
								// and it has a config tag.  Let's see if it is
								// part of this config.
								String alternateConfigProp =
									moduleList.getProperty(alternateImplConfigKey);

								// we know that there are
								// derby.module.<tag>J2 and
								// derby.module.<tag>J1 and
								// derby.env.jdk.<tag>J2 and
								// derby.env.jdk.<tag>J1 and
								// cloudscape.config.<tag>J2 and 
								// cloudscape.config.<tag>J1
								StringTokenizer st2 = new
									StringTokenizer(alternateConfigProp, ",");

								boolean ok = false;
								while(st2.hasMoreTokens()) 
								{
									String s = st2.nextToken().trim();

									if (s.equalsIgnoreCase(config) ||
										s.equalsIgnoreCase("all"))
									{
										ok = true;
										break;
									}
								}
								// the alternate module impl is not part of
								// this config, do not save the jdk env key
								if (!ok) 
									saveEnvKey = false;
							}
						}

						if (saveEnvKey)
							outputProp.put(envKey, moduleList.getProperty(envKey));
					}
					


					// NOTE, if other types of properties are added to
					// modules.properties, be sure to add it here too.
				}
			}
		}

		FileOutputStream os = new FileOutputStream(outputfile);
		try
		{
			outputProp.store(os,
							header.
							concat("# config is ").concat(config).
							concat(footer));
		}
		finally
		{
			if (os != null)
				os.close();
		}
	}


	private static void printUsageAndExit()
	{
		StringBuffer buf = new StringBuffer(400);

		buf.append("Usage propertyConfig <masterFile> <config> <outputFile>\n")
			.append("masterFile must be a pre-existing properties file ")
			.append("containing all the modules properites\n")
			.append("config must be a configuration defined in ")
			.append("org.apache.derby.modules.properties.\n")
			.append("outputFile must not be a pre-existing properties file.\n\n")
			.append("propertyConfig will generate the outputFile based on")
			.append("the masterfile and the configuration specified.")
			.append("\n\nE.g., java propertyConfig dbms.properties cloudsync dbms.cloudsync.properties\n");
		

		System.out.println(buf.toString());
		System.exit(1);
	}
}