/*
 * Copyright 2004-2008 H2 Group. Licensed under the H2 License, Version 1.0
 * (http://h2database.com/html/license.html).
 * Initial Developer: H2 Group
 */
package org.h2.server.web;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.StringReader;
import java.io.StringWriter;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.Socket;
import java.security.SecureClassLoader;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.ParameterMetaData;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Types;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Locale;
import java.util.Map;
import java.util.Properties;
import java.util.Random;
import java.util.StringTokenizer;
import java.util.Map.Entry;

import org.h2.api.DatabaseEventListener;
import org.h2.bnf.Bnf;
import org.h2.constant.ErrorCode;
import org.h2.engine.Constants;
import org.h2.jdbc.JdbcSQLException;
import org.h2.message.TraceSystem;
import org.h2.tools.SimpleResultSet;
import org.h2.util.IOUtils;
import org.h2.util.JdbcUtils;
import org.h2.util.MathUtils;
import org.h2.util.MemoryUtils;
import org.h2.util.NetUtils;
import org.h2.util.ObjectArray;
import org.h2.util.ObjectUtils;
import org.h2.util.ScriptReader;
import org.h2.util.StringUtils;

/**
 * For each connection to a session, an object of this class is created.
 * This class is used by the H2 Console.
 */
class WebThread extends Thread implements DatabaseEventListener {
    private WebServer server;
    private WebSession session;
    private Properties attributes;
    private Socket socket;

    private InputStream input;
    private OutputStream output;
    private String ifModifiedSince;
    private String mimeType;
    private boolean cache;
    private int listenerLastState;
    private long listenerLastEvent;
    private boolean stop;

    // TODO web: support online data editing like http://numsum.com/

    WebThread(Socket socket, WebServer server) {
        this.server = server;
        this.socket = socket;
        setName("H2 Console thread");
    }

    void setSession(WebSession session, Properties attributes) {
        this.session = session;
        this.attributes = attributes;
    }

    public void stopNow() {
        this.stop = true;
    }

    private String getAllowedFile(String requestedFile) {
        if (!allow()) {
            return "notAllowed.jsp";
        }
        if (requestedFile.length() == 0) {
            return "index.do";
        }
        return requestedFile;
    }

    public String processRequest(String file, String hostAddr) {
        int index = file.lastIndexOf('.');
        String suffix;
        if (index >= 0) {
            suffix = file.substring(index + 1);
        } else {
            suffix = "";
        }
        if ("ico".equals(suffix)) {
            mimeType = "image/x-icon";
            cache = true;
        } else if ("gif".equals(suffix)) {
            mimeType = "image/gif";
            cache = true;
        } else if ("css".equals(suffix)) {
            cache = true;
            mimeType = "text/css";
        } else if ("html".equals(suffix) || "do".equals(suffix) || "jsp".equals(suffix)) {
            cache = false;
            mimeType = "text/html";
            if (session == null) {
                session = server.createNewSession(hostAddr);
                if (!"notAllowed.jsp".equals(file)) {
                    file = "index.do";
                }
            }
        } else if ("js".equals(suffix)) {
            cache = true;
            mimeType = "text/javascript";
        } else {
            cache = false;
            mimeType = "text/html";
            file = "error.jsp";
            server.trace("unknown mime type, file " + file);
        }
        server.trace("mimeType=" + mimeType);
        server.trace(file);
        if (file.endsWith(".do")) {
            file = process(file);
        }
        return file;
    }

    public void run() {
        try {
            input = new BufferedInputStream(socket.getInputStream());
            output = new BufferedOutputStream(socket.getOutputStream());
            while (true) {
                if (!process()) {
                    break;
                }
            }
        } catch (IOException e) {
            TraceSystem.traceThrowable(e);
        } catch (SQLException e) {
            TraceSystem.traceThrowable(e);
        }
        IOUtils.closeSilently(output);
        IOUtils.closeSilently(input);
        try {
            socket.close();
        } catch (IOException e) {
            // ignore
        } finally {
            server.remove(this);
        }
    }

    public boolean process() throws IOException, SQLException {
        boolean keepAlive = false;
        String head = readHeaderLine();
        if (head.startsWith("GET ") || head.startsWith("POST ")) {
            int begin = head.indexOf('/'), end = head.lastIndexOf(' ');
            String file = head.substring(begin + 1, end).trim();
            server.trace(head + ": " + file);
            file = getAllowedFile(file);
            attributes = new Properties();
            int paramIndex = file.indexOf("?");
            session = null;
            if (paramIndex >= 0) {
                String attrib = file.substring(paramIndex + 1);
                parseAttributes(attrib);
                String sessionId = attributes.getProperty("jsessionid");
                file = file.substring(0, paramIndex);
                session = server.getSession(sessionId);
            }
            keepAlive = parseHeader();
            String hostAddr = socket.getInetAddress().getHostAddress();
            file = processRequest(file, hostAddr);
            if (file.length() == 0) {
                // asynchronous request
                return true;
            }
            String message;
            byte[] bytes;
            if (cache && ifModifiedSince != null && ifModifiedSince.equals(server.getStartDateTime())) {
                bytes = null;
                message = "HTTP/1.1 304 Not Modified\n";
            } else {
                bytes = server.getFile(file);
                if (bytes == null) {
                    message = "HTTP/1.0 404 Not Found\n";
                    bytes = StringUtils.utf8Encode("File not found: " + file);
                } else {
                    if (session != null && file.endsWith(".jsp")) {
                        String page = StringUtils.utf8Decode(bytes);
                        page = PageParser.parse(server, page, session.map);
                        try {
                            bytes = StringUtils.utf8Encode(page);
                        } catch (SQLException e) {
                            server.traceError(e);
                        }
                    }
                    message = "HTTP/1.1 200 OK\n";
                    message += "Content-Type: " + mimeType + "\n";
                    if (!cache) {
                        message += "Cache-Control: no-cache\n";
                    } else {
                        message += "Cache-Control: max-age=10\n";
                        message += "Last-Modified: " + server.getStartDateTime() + "\n";
                    }
                    message += "Content-Length: " + bytes.length + "\n";
                }
            }
            message += "\n";
            server.trace(message);
            output.write(message.getBytes());
            if (bytes != null) {
                output.write(bytes);
            }
            output.flush();
        }
        return keepAlive;
    }

    protected String getComboBox(String[] elements, String selected) {
        StringBuffer buff = new StringBuffer();
        for (int i = 0; i < elements.length; i++) {
            String value = elements[i];
            buff.append("<option value=\"");
            buff.append(PageParser.escapeHtmlData(value));
            buff.append("\"");
            if (value.equals(selected)) {
                buff.append(" selected");
            }
            buff.append(">");
            buff.append(PageParser.escapeHtml(value));
            buff.append("</option>");
        }
        return buff.toString();
    }

    protected String getComboBox(String[][] elements, String selected) {
        StringBuffer buff = new StringBuffer();
        for (int i = 0; i < elements.length; i++) {
            String[] n = elements[i];
            buff.append("<option value=\"");
            buff.append(PageParser.escapeHtmlData(n[0]));
            buff.append("\"");
            if (n[0].equals(selected)) {
                buff.append(" selected");
            }
            buff.append(">");
            buff.append(PageParser.escapeHtml(n[1]));
            buff.append("</option>");
        }
        return buff.toString();
    }

    private String readHeaderLine() throws IOException {
        StringBuffer buff = new StringBuffer();
        while (true) {
            int i = input.read();
            if (i == -1) {
                throw new IOException("Unexpected EOF");
            } else if (i == '\r' && input.read() == '\n') {
                return buff.length() > 0 ? buff.toString() : null;
            } else {