/*
    Dateiverwaltung - File management in your browser
    Copyright (C) 2017 Ulrich Hilger, http://uhilger.de

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as
    published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package de.uhilger.filecms.api;

import de.uhilger.filecms.data.FileRef;
import de.uhilger.filecms.web.Initialiser;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang.StringEscapeUtils;

/**
 *
 * @author ulrich
 */
public class FileMgr extends Api {
  private static final Logger logger = Logger.getLogger(FileMgr.class.getName());
  
  public static final String PUB_DIR_PATH = "www/";
  public static final String HOME_DIR_PATH = "home/";
  public static final String PUB_DIR_NAME = "Oeffentlich";
  public static final String HOME_DIR_NAME = "Persoenlicher Ordner";
  
  public static final int OP_COPY = 1;
  public static final int OP_MOVE = 2;
  
  public String hallo() {
    return "Hallo Welt!";
  }
  
  public List<FileRef> list(String relPath) {
    List<FileRef> files = new ArrayList();
    if(relPath.length() == 0) {
      FileRef namedPublicFolder = new FileRef(PUB_DIR_NAME, true);
      logger.finer(namedPublicFolder.getAbsolutePath());
      FileRef namedHomeFolder = new FileRef(HOME_DIR_NAME, true);
      logger.finer(namedHomeFolder.getAbsolutePath());
      files = new ArrayList();
      files.add(namedHomeFolder);
      files.add(namedPublicFolder);
    } else {
      String path = getTargetDir(relPath).getAbsolutePath();
      logger.fine("listing path: " + path);
      File dir = new File(path);
      if(dir.exists()) {
        File[] fileArray = dir.listFiles();
        for(int i = 0; i < fileArray.length; i++) {
          logger.fine(fileArray[i].toURI().toString());
          String fname = fileArray[i].toURI().toString().replace("file:/", "");
          if(fileArray[i].isDirectory()) {
            fname = fname.substring(0, fname.length() - 1);
          }
          logger.fine(fname);
          files.add(new FileRef(fname, fileArray[i].isDirectory()));
        }
      }
    }    
    return files;
  }
  
  public FileRef newFolder(String relPath, String folderName) {
    logger.finer(relPath);
    String targetPath = null;
    if(relPath.startsWith(PUB_DIR_NAME)) {
      targetPath = PUB_DIR_PATH + getUserName() + "/" + relPath.substring(PUB_DIR_NAME.length()) + "/" + folderName;
    } else if(relPath.startsWith(HOME_DIR_NAME)) {
      targetPath = HOME_DIR_PATH + getUserName() + "/" + relPath.substring(HOME_DIR_NAME.length()) + "/" + folderName;
    } else {
      // kann eigentlich nicht sein..
    }
    logger.finer(targetPath);
    File targetDir = new File(getBase().getAbsolutePath(), targetPath);
    targetDir.mkdirs();
    return new FileRef(targetDir.getAbsolutePath(), true);
  }
  
  public String getCode(String relPath, String fileName) {
    String code = null;
    
    Object p = getRequest().getUserPrincipal();
    if(p instanceof Principal) {
      Reader reader = null;
      try {
        File targetFile = new File(getTargetDir(relPath), fileName);
        
        //reader = new InputStreamReader(new FileInputStream(targetFile), "UTF8");
        
        reader = new FileReader(targetFile);
        StringBuffer buf = new StringBuffer();
        char[] readBuffer = new char[1024];
        int charsRead = reader.read(readBuffer);
        while(charsRead > -1) {
          buf.append(readBuffer, 0, charsRead);
          charsRead = reader.read(readBuffer);
        }
        code = buf.toString();
      } catch (FileNotFoundException ex) {
        Logger.getLogger(FileMgr.class.getName()).log(Level.SEVERE, null, ex);
      } catch (IOException ex) {
        Logger.getLogger(FileMgr.class.getName()).log(Level.SEVERE, null, ex);
      } finally {
        try {
          reader.close();
        } catch (IOException ex) {
          Logger.getLogger(FileMgr.class.getName()).log(Level.SEVERE, null, ex);
        }
      }
      
    }    
    
    return code;
  }
  
  public String renameFile(String relPath, String fname, String newName) {
    File targetDir = getTargetDir(relPath);
    File file = new File(targetDir, fname);
    file.renameTo(new File(targetDir, newName));
    return fname + " umbenannt zu " + newName;
  }
  
  public String deleteFiles(String relPath, List fileNames) {
    String result = null;
    try {
      logger.fine(fileNames.toString());
      File targetDir = getTargetDir(relPath);
      for(int i=0; i < fileNames.size(); i++) {
        Object o = fileNames.get(i);
        if(o instanceof ArrayList) {
          ArrayList al = (ArrayList) o;
          logger.fine(al.get(0).toString());
          File targetFile = new File(targetDir, al.get(0).toString());
          logger.fine(targetFile.getAbsolutePath());
          if(targetFile.isDirectory()) {
            FileUtils.deleteDirectory(targetFile);
          } else {
            targetFile.delete();
          }
        }
      }
      result = "deleted";
    } catch (Throwable ex) {
      logger.log(Level.SEVERE, ex.getLocalizedMessage(), ex);
    }
    return result;
  }
  
  public String copyFiles(String fromPath, String toPath, List fileNames) {
    return copyOrMoveFiles(fromPath, toPath, fileNames, OP_COPY);
  }
  
  public String moveFiles(String fromPath, String toPath, List fileNames) {
    return copyOrMoveFiles(fromPath, toPath, fileNames, OP_MOVE);
  }
  
  private String copyOrMoveFiles(String fromPath, String toPath, List fileNames, int operation) {
    String result = null;
    try {
      File srcDir = getTargetDir(fromPath);
      File targetDir = getTargetDir(toPath);
      Iterator i = fileNames.iterator();
      while(i.hasNext()) {
        Object o = i.next();
        if (o instanceof ArrayList) {
          ArrayList al = (ArrayList) o;
          File srcFile = new File(srcDir, al.get(0).toString());
          if(srcFile.isDirectory()) {
            if(operation == OP_MOVE) {
              FileUtils.moveDirectoryToDirectory(srcFile, targetDir, false);
            } else {
              FileUtils.copyDirectoryToDirectory(srcFile, targetDir);
            }
          } else {
            if(operation == OP_MOVE) {
              FileUtils.moveFileToDirectory(srcFile, targetDir, false);
            } else {
              FileUtils.copyFileToDirectory(srcFile, targetDir);              
            }
          }
        }
      }
    } catch (IOException ex) {
      logger.log(Level.SEVERE, ex.getLocalizedMessage(), ex);
    }
    return result;
  }
  
  public FileRef saveTextFileAs(String relPath, String fileName, String contents) {
    FileRef savedFile = null;
    logger.fine(relPath + " " + fileName);
    //FileRef datenRef = getBase();
    Object p = getRequest().getUserPrincipal();
    if(p instanceof Principal) {
      File targetFile = new File(getTargetDir(relPath), fileName);
      if(targetFile.exists()) {
        targetFile = getNewFileName(targetFile);
      } else {
        targetFile.getParentFile().mkdirs();
      }
      saveToFile(targetFile, contents);
    }
    return savedFile;
  }
  
  private File getNewFileName(File file) {
    File dir = file.getParentFile();
    String targetName = file.getName();
    logger.fine("targetName: " + targetName);
    String ext = "";
    int dotpos = targetName.indexOf(".");
    if(dotpos > -1) {
      ext = targetName.substring(dotpos);
      targetName = targetName.substring(0, dotpos);
    }
    logger.fine("targetName: " + targetName + ", ext: " + ext);
    int i = 1;
    while(file.exists()) {
      StringBuffer buf = new StringBuffer();
      buf.append(targetName);
      buf.append("-");
      buf.append(i);
      if(ext.length() > 0) {
        buf.append(ext);
      }
      file = new File(dir, buf.toString());
      i++;
    }
    logger.fine("new file: " + file.getName());
    return file;
  }  
  
  private FileRef saveToFile(File targetFile, String contents) {
    FileRef savedFile = null;
    try {
      targetFile.createNewFile();
      FileWriter w = new FileWriter(targetFile);
      //w.write(StringEscapeUtils.unescapeHtml(contents));
      w.write(contents);
      w.flush();
      w.close();
      savedFile = new FileRef(
              targetFile.getAbsolutePath(),
              targetFile.isDirectory(),
              targetFile.isHidden(),
              targetFile.lastModified(),
              targetFile.length());
    } catch (IOException ex) {
      logger.log(Level.SEVERE, ex.getLocalizedMessage(), ex);
    }
    return savedFile;
  }
  
  public FileRef saveTextFile(String relPath, String fileName, String contents) {
    FileRef savedFile = null;
    logger.fine(relPath + " " + fileName);
    //FileRef datenRef = getBase();
    Object p = getRequest().getUserPrincipal();
    if(p instanceof Principal) {
      File targetFile = new File(getTargetDir(relPath), fileName);
      if(targetFile.exists()) {
        /*
          muss delete() sein?
          pruefen: ueberschreibt der FileWriter den alteen Inhalt oder 
          entsteht eine unerwuenschte Mischung aus altem und neuem 
          Inhalt?
        */
        targetFile.delete();
      } else {
        targetFile.getParentFile().mkdirs();
      }
      saveToFile(targetFile, contents);
    }
    return savedFile;
  }
    
  /* ---- Hilfsfunktionen ---- */
  
  private File getTargetDir(String relPath) {
    logger.fine(relPath);
    String targetPath = null;
    if(relPath.startsWith(PUB_DIR_NAME)) {
      targetPath = PUB_DIR_PATH + getUserName() + relPath.substring(PUB_DIR_NAME.length());
    } else if(relPath.startsWith(HOME_DIR_NAME)) {
      targetPath = HOME_DIR_PATH + getUserName() + relPath.substring(HOME_DIR_NAME.length());
    } else {
      // kann eigentlich nicht sein..
    }
    logger.fine(targetPath);
    File targetDir = new File(getBase().getAbsolutePath(), targetPath);
    return targetDir;
  }
  
  private FileRef getBase() {
    FileRef base = null;
    Object o = getServletContext().getAttribute(Initialiser.FILE_BASE);
    if(o instanceof String) {
      String baseStr = (String) o;
      logger.fine(baseStr);
      File file = new File(baseStr);
      base = new FileRef(file.getAbsolutePath(), file.isDirectory());
    }
    return base;
  }
  
  private String getUserName() {
    String userName = null;
    Object p = getRequest().getUserPrincipal();
    if(p instanceof Principal) {
      userName = ((Principal) p).getName();
    }
    return userName;
  }    
}