/*
    * 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.hadoop.chukwa.hicc;
  
  
  import java.io.*;
  import java.nio.charset.Charset;
  import java.util.*;
  
  import org.json.simple.JSONArray;
  import org.json.simple.JSONObject;
  import org.json.simple.JSONValue;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.chukwa.util.ExceptionUtil;
  
  public class Views {
    public JSONArray viewsData;
    private String path = System.getenv("CHUKWA_DATA_DIR")
        + "/views/workspace_view_list.cache";
    private static final Log log = LogFactory.getLog(Views.class);
  
    static public String getContents(File aFile) {
      // ...checks on aFile are elided
      StringBuffer contents = new StringBuffer();
  
      try {
        // use buffering, reading one line at a time
        // FileReader always assumes default encoding is OK!
        BufferedReader input = new BufferedReader(new InputStreamReader(new FileInputStream(aFile.getAbsolutePath()), Charset.forName("UTF-8")));
        try {
          String line = null; // not declared within while loop
          /*
           * readLine is a bit quirky : it returns the content of a line MINUS the
           * newline. it returns null only for the END of the stream. it returns
           * an empty String if two newlines appear in a row.
           */
          while ((line = input.readLine()) != null) {
            contents.append(line);
            contents.append(System.getProperty("line.separator"));
          }
        } finally {
          input.close();
        }
      } catch (IOException ex) {
        ex.printStackTrace();
      }
  
      return contents.toString();
    }
  
    public Views() {
      File aFile = new File(path);
      String buffer = getContents(aFile);
      try {
        viewsData = (JSONArray) JSONValue.parse(buffer);
      } catch (Exception e) {
        log.debug(ExceptionUtil.getStackTrace(e));
      }
    }
  
    public String getOwner(int i) {
      String owner = null;
      try {
        owner = ((JSONObject) viewsData.get(i)).get("owner")
            .toString();
      } catch (Exception e) {
        log.debug(ExceptionUtil.getStackTrace(e));
      }
      return owner;
    }
  
    public Iterator getPermission(int i) {
      Iterator permission = null;
      try {
        permission = ((JSONObject) ((JSONObject) viewsData.get(i))
            .get("permission")).keySet().iterator();
      } catch (Exception e) {
        log.debug(ExceptionUtil.getStackTrace(e));
      }
      return permission;
    }
  
   public String getReadPermission(int i, String who) {
     String read = null;
     try {
       JSONObject view = (JSONObject) viewsData.get(i);
       JSONObject permission = (JSONObject) view.get("permission");
       JSONObject user = (JSONObject) permission.get(who);
       read = user.get("read").toString();
     } catch (Exception e) {
       log.debug(ExceptionUtil.getStackTrace(e));
     }
     return read;
   }
 
   public String getWritePermission(int i, String who) {
     String write = null;
     try {
       write = ((JSONObject) ((JSONObject) ((JSONObject) viewsData.get(i)).get("permission")).get(who)).get("write").toString();
     } catch (Exception e) {
       log.debug(ExceptionUtil.getStackTrace(e));
     }
     return write;
   }
 
   public String getDescription(int i) {
     String description = null;
     try {
       description = ((JSONObject) viewsData.get(i)).get(
           "description").toString();
     } catch (Exception e) {
       log.debug(ExceptionUtil.getStackTrace(e));
     }
     return description;
   }
 
   public String getKey(int i) {
     String key = null;
     try {
       key = ((JSONObject) viewsData.get(i)).get("key").toString();
     } catch (Exception e) {
       log.debug(ExceptionUtil.getStackTrace(e));
     }
     return key;
   }
 
   public int length() {
     return viewsData.size();
   }
 }