//ViewFile.java
//-----------------------
//part of YaCy
//(C) by Michael Peter Christen; mc@anomic.de
//first published on http://www.anomic.de
//Frankfurt, Germany, 2004

//last major change: 12.07.2004

//This program is free software; you can redistribute it and/or modify
//it under the terms of the GNU General Public License as published by
//the Free Software Foundation; either version 2 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 General Public License for more details.

//You should have received a copy of the GNU General Public License
//along with this program; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

//Using this software in any meaning (reading, learning, copying, compiling,
//running) means that you agree that the Author(s) is (are) not responsible
//for cost, loss of data or any harm that may be caused directly or indirectly
//by usage of this softare or this documentation. The usage of this software
//is on your own risk. The installation and usage (starting/running) of this
//software may allow other people or application to access your computer and
//any attached devices and is highly dependent on the configuration of the
//software which must be done by the user of the software; the author(s) is
//(are) also not responsible for proper configuration and usage of the
//software, even if provoked by documentation provided together with
//the software.

//Any changes to this file according to the GPL as documented in the file
//gpl.txt aside this file in the shipment you received can be done to the
//lines that follows this copyright notice here, but changes must not be
//done inside the copyright notive above. A re-distribution must contain
//the intact and unchanged copyright notice.
//Contributions and changes to the program code must be marked as such.

//you must compile this file with
//javac -classpath .:../Classes Status.java
//if the shell's current path is HTROOT

import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.MalformedURLException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.Enumeration;

import de.anomic.data.wikiCode;
import de.anomic.http.httpHeader;
import de.anomic.http.httpc;
import de.anomic.index.indexURLEntry;
import de.anomic.net.URL;
import de.anomic.plasma.plasmaHTCache;
import de.anomic.plasma.plasmaParserDocument;
import de.anomic.plasma.plasmaSwitchboard;
import de.anomic.plasma.cache.IResourceInfo;
import de.anomic.plasma.crawler.plasmaCrawlerException;
import de.anomic.plasma.parser.ParserException;
import de.anomic.server.serverFileUtils;
import de.anomic.server.serverObjects;
import de.anomic.server.serverSwitch;

public class ViewFile {

    public static final int VIEW_MODE_NO_TEXT = 0;
    public static final int VIEW_MODE_AS_PLAIN_TEXT = 1;
    public static final int VIEW_MODE_AS_PARSED_TEXT = 2;
    public static final int VIEW_MODE_AS_PARSED_SENTENCES = 3;
    public static final int VIEW_MODE_AS_IFRAME = 4;

    public static final String[] highlightingColors = new String[] {
        "255,255,100",
        "255,155,155",
        "0,255,0",
        "0,255,255",
        "204,153,0",
        "204,153,255"
    };

    public static serverObjects respond(httpHeader header, serverObjects post, serverSwitch env) {

        serverObjects prop = new serverObjects();
        plasmaSwitchboard sb = (plasmaSwitchboard)env;     

        if (post != null && post.containsKey("words")) try {
            prop.put("error_words",URLEncoder.encode((String) post.get("words"), "UTF-8"));
        } catch (UnsupportedEncodingException e1) {
            // ignore this. this should not occure
        }

        String viewMode = post.get("viewMode","sentences");
        URL url = null;
        String descr = "";
        int wordCount = 0;
        int size = 0;    
        
        // getting the url hash from which the content should be loaded
        String urlHash = post.get("urlHash","");       
        if (urlHash.length() > 0) {
            // getting the urlEntry that belongs to the url hash
            indexURLEntry urlEntry = null;
            urlEntry = sb.urlPool.loadedURL.load(urlHash, null);
            if (urlEntry == null) {
                prop.put("error",2);
                prop.put("viewMode",VIEW_MODE_NO_TEXT);
                return prop;
            }            
            
                // gettin the url that belongs to the entry
            indexURLEntry.Components comp = urlEntry.comp();
            if ((comp == null) || (comp.url() == null)) {
                prop.put("error", 3);
                prop.put("viewMode", VIEW_MODE_NO_TEXT);
                return prop;
            }
            url = comp.url();
            descr = comp.descr();
            urlEntry.wordCount();
            size = urlEntry.size();
        }

        // alternatively, get the url simply from a url String
        // this can be used as a simple tool to test the text parser
        String urlString = post.get("url", "");
        if (urlString.length() > 0) try {
            // this call forces the peer to download  web pages
            // it is therefore protected by the admin password
            
            if (!sb.verifyAuthentication(header, false)) {
                prop.put("AUTHENTICATE", "admin log-in"); // force log-in
                return prop;
            }

            // define an url by post parameter
            url = new URL(urlString);
        } catch (MalformedURLException e) {}
        
        
        if (url == null) {
            prop.put("error", 1);
            prop.put("viewMode", VIEW_MODE_NO_TEXT);
            return prop;
        }

        // loading the resource content as byte array
        InputStream resource = null;
        long resourceLength = -1;
        IResourceInfo resInfo = null;
        String resMime = null;
        try {
            // trying to load the resource body
            resource = sb.cacheManager.getResourceContentStream(url);
            resourceLength = sb.cacheManager.getResourceContentLength(url);

            // if the resource body was not cached we try to load it from web
            if (resource == null) {
                plasmaHTCache.Entry entry = null;
                try {
                    entry = sb.snippetCache.loadResourceFromWeb(url, 5000, false);
                } catch (plasmaCrawlerException e) {
                    prop.put("error", 4);
                    prop.put("error_errorText", e.getMessage());
                    prop.put("viewMode", VIEW_MODE_NO_TEXT);
                    return prop;
                }

                if (entry != null) {
                    resInfo = entry.getDocumentInfo();
                    resource = sb.cacheManager.getResourceContentStream(url);
                    resourceLength = sb.cacheManager.getResourceContentLength(url);
                }

                if (resource == null) {
                    prop.put("error", 4);
                    prop.put("error_errorText", "No resource available");
                    prop.put("viewMode", VIEW_MODE_NO_TEXT);
                    return prop;
                }
            }

            // try to load resource metadata
            if (resInfo == null) {

                // try to load the metadata from cache
                try {
                    resInfo = sb.cacheManager.loadResourceInfo(url);
                } catch (Exception e) {
                    /* ignore this */
                }

                // if the metadata where not cached try to load it from web
                if (resInfo == null) {
                    String protocol = url.getProtocol();
                    if (!((protocol.equals("http") || protocol.equals("https")))) {
                        prop.put("error", 6);
                        prop.put("viewMode", VIEW_MODE_NO_TEXT);
                        return prop;
                    }

                    httpHeader responseHeader = httpc.whead(url, url.getHost(), 5000, null, null, sb.remoteProxyConfig);
                    if (responseHeader == null) {
                        prop.put("error", 4);
                        prop.put("error_errorText", "Unable to load resource metadata.");
                        prop.put("viewMode", VIEW_MODE_NO_TEXT);
                        return prop;
                    }
                    try {
                        resInfo = sb.cacheManager.getResourceInfoFactory().buildResourceInfoObj(url, responseHeader);
                    } catch (Exception e) {
                        prop.put("error", 4);
                        prop.put("error_errorText", e.getMessage());
                        prop.put("viewMode", VIEW_MODE_NO_TEXT);
                        return prop;
                    }
                    resMime = responseHeader.mime();
                }
            } else {
                resMime = resInfo.getMimeType();
            }
        } catch (IOException e) {
            if (resource != null)
                try {
                    resource.close();
                } catch (Exception ex) {
                    /* ignore this */
                }
            prop.put("error", 4);
            prop.put("error_errorText", e.getMessage());
            prop.put("viewMode", VIEW_MODE_NO_TEXT);
            return prop;
        }

        if (viewMode.equals("plain")) {

            // TODO: how to handle very large files here ?
            String content;
            try {
                content = new String(serverFileUtils.read(resource), "UTF-8");
            } catch (Exception e) {
                prop.put("error", 4);
                prop.put("error_errorText", e.getMessage());
                prop.put("viewMode", VIEW_MODE_NO_TEXT);
                return prop;
            } finally {
                if (resource != null)
                    try {
                        resource.close();
                    } catch (Exception e) {
                        /* ignore this */
                    }
            }

            content = content.replaceAll("<", "&lt;").replaceAll(">", "&gt;")
                    .replaceAll("\"", "&quot;").replaceAll("\n", "<br>")
                    .replaceAll("\t", "&nbsp;&nbsp;&nbsp;&nbsp;");

            prop.put("error", 0);
            prop.put("viewMode", VIEW_MODE_AS_PLAIN_TEXT);
            prop.put("viewMode_plainText", content);
        } else if (viewMode.equals("iframe")) {
            prop.put("viewMode", VIEW_MODE_AS_IFRAME);
            prop.put("viewMode_url", url.toNormalform());
        } else if (viewMode.equals("parsed") || viewMode.equals("sentences")) {
            // parsing the resource content
            plasmaParserDocument document = null;
            try {
                document = sb.snippetCache.parseDocument(url, resourceLength, resource, resInfo);
                if (document == null) {
                    prop.put("error", 5);
                    prop.put("error_errorText", "Unknown error");
                    prop.put("viewMode", VIEW_MODE_NO_TEXT);
                    return prop;
                }
            } catch (ParserException e) {
                prop.put("error", 5);
                prop.put("error_errorText", e.getMessage());
                prop.put("viewMode", VIEW_MODE_NO_TEXT);
                return prop;
            } finally {
                if (resource != null)
                    try {
                        resource.close();
                    } catch (Exception e) {
                        /* ignore this */
                    }
            }

            resMime = document.getMimeType();

            if (viewMode.equals("parsed")) {
                String content = new String(document.getTextBytes());
                content = wikiCode.replaceHTML(content); // added by Marc Nause
                content = content.replaceAll("\n", "<br>").replaceAll("\t", "&nbsp;&nbsp;&nbsp;&nbsp;");

                prop.put("viewMode", VIEW_MODE_AS_PARSED_TEXT);
                prop.put("viewMode_parsedText", content);
            } else {
                prop.put("viewMode", VIEW_MODE_AS_PARSED_SENTENCES);
                final Enumeration sentences = document.getSentences(null); // FIXME: apply correct charset

                boolean dark = true;
                int i = 0;
                if (sentences != null)
                    while (sentences.hasMoreElements()) {
                        String currentSentence = wikiCode
                                .replaceHTML((String) sentences.nextElement());

                        // Search word highlighting
                        String words = post.get("words", null);
                        if (words != null) {
                            try {
                                words = URLDecoder.decode(words, "UTF-8");
                            } catch (UnsupportedEncodingException e) {
                            }

                            String[] wordArray = words.substring(1,
                                    words.length() - 1).split(",");
                            for (int j = 0; j < wordArray.length; j++) {
                                String currentWord = wordArray[j].trim();
                                currentSentence = currentSentence.replaceAll(
                                        currentWord,
                                        "<b style=\"color: black; background-color: rgb("
                                                + highlightingColors[j % 6]
                                                + ");\">" + currentWord
                                                + "</b>");
                            }
                        }

                        prop.put("viewMode_sentences_" + i + "_nr", Integer.toString(i + 1));
                        prop.put("viewMode_sentences_" + i + "_text", currentSentence);
                        prop.put("viewMode_sentences_" + i + "_dark", ((dark) ? 1 : 0));
                        dark = !dark;
                        i++;
                    }
                prop.put("viewMode_sentences", i);

            }
            if (document != null) document.close();
        }
        prop.put("error", 0);
        prop.put("error_url", url.toNormalform());
        prop.put("error_hash", urlHash);
        prop.put("error_wordCount", Integer.toString(wordCount));
        prop.put("error_desc", descr);
        prop.put("error_size", size);
        prop.put("error_mimeType", resMime);

        return prop;
    }

}