/*
 * Copyright 2004-2009 H2 Group. Multiple-Licensed under the H2 License,
 * Version 1.0, and under the Eclipse Public License, Version 1.0
 * (http://h2database.com/html/license.html).
 */
/*
 * 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.h2.test.trace;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;
import java.util.HashMap;
import org.h2.util.New;

/**
 * This tool can re-run Java style log files. There is no size limit.
 */
public class Player {

    // TODO support InputStream;
    // TODO support Reader;
    // TODO support int[];
    // TODO support Blob and Clob;
    // TODO support Calendar
    // TODO support Object
    // TODO support Object[]
    // TODO support URL
    // TODO support Array
    // TODO support Ref
    // TODO support SQLInput, SQLOutput
    // TODO support Properties
    // TODO support Map
    // TODO support SQLXML

    private static final String[] IMPORTED_PACKAGES = { "", "java.lang.", "java.sql.", "javax.sql." };
    private boolean trace;
    private HashMap<String, Object> objects = New.hashMap();

    /**
     * Execute a trace file using the command line. The log file name to execute
     * (replayed) must be specified as the last parameter. The following
     * optional command line parameters are supported:
     * <ul>
     * <li><code>-log</code> to enable logging the executed statement to
     * System.out
     * </ul>
     *
     * @param args the arguments of the application
     */
    public static void main(String... args) throws IOException {
        new Player().run(args);
    }

    /**
     * Execute a trace file.
     *
     * @param fileName the file name
     * @param log print debug information
     * @param checkResult if the result of each method should be compared
     *            against the result in the file
     */
    public static void execute(String fileName, boolean log, boolean checkResult) throws IOException {
        new Player().runFile(fileName, log);
    }

    private void run(String... args) throws IOException {
        String fileName = "test.log.db";
        try {
            fileName = args[args.length - 1];
            for (int i = 0; i < args.length - 1; i++) {
                if ("-trace".equals(args[i])) {
                    trace = true;
                } else {
                    throw new Error("Unknown setting: " + args[i]);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("Usage: java " + getClass().getName()
                    + " [-trace] <fileName>");
            return;
        }
        runFile(fileName, trace);
    }

    private void runFile(String fileName, boolean trace) throws IOException {
        this.trace = trace;
        LineNumberReader reader = new LineNumberReader(new BufferedReader(
                new FileReader(fileName)));
        while (true) {
            String line = reader.readLine();
            if (line == null) {
                break;
            }
            runLine(line.trim());
        }
    }

    /**
     * Write trace information if trace is enabled.
     *
     * @param s the message to write
     */
    void trace(String s) {
        if (trace) {
            System.out.println(s);
        }
    }

    private void runLine(String line) {
        if (!line.startsWith("/**/")) {
            return;
        }
        line = line.substring("/**/".length()) + ";";
        Statement s = Parser.parseStatement(this, line);
        trace("> " + s.toString());
        try {
            s.execute();
        } catch (Exception e) {
            e.printStackTrace();
            trace("error: " + e.toString());
        }
    }

    /**
     * Get the class for the given class name.
     * Only a limited set of classes is supported.
     *
     * @param className the class name
     * @return the class
     */
    static Class< ? > getClass(String className) {
        for (String s : IMPORTED_PACKAGES) {
            try {
                return Class.forName(s + className);
            } catch (ClassNotFoundException e) {
                // ignore
            }
        }
        throw new Error("Class not found: " + className);
    }

    /**
     * Assign an object to a variable.
     *
     * @param variableName the variable name
     * @param obj the object
     */
    void assign(String variableName, Object obj) {
        objects.put(variableName, obj);
    }

    /**
     * Get an object.
     *
     * @param name the variable name
     * @return the object
     */
    Object getObject(String name) {
        return objects.get(name);
    }

}
