/*
 * Concept profile generation tool suite
 * Copyright (C) 2015 Biosemantics Group, Erasmus University Medical Center,
 *  Rotterdam, The Netherlands
 * 
 * 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 org.erasmusmc.utilities;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class ReadTextFile implements Iterable<String>{
  public String filename;
  protected BufferedReader bufferedReader;
  public boolean EOF = false;

  
  public ReadTextFile(InputStream inputStream) {
  	 try {
			bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
		} catch (UnsupportedEncodingException e) {
      System.err.println("Computer does not support UTF-8 encoding");
			e.printStackTrace();
		}
  	
  }
  public ReadTextFile(String filename) {
    this.filename = filename;
    try {
      FileInputStream inputStream = new FileInputStream(filename);
      bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"));
    } catch (FileNotFoundException e) {
      e.printStackTrace();
    } catch (UnsupportedEncodingException e) {
      System.err.println("Computer does not support UTF-8 encoding");
      e.printStackTrace();
    }
  }
  

  public Iterator<String> getIterator() {
    return iterator();
  }

  public List<String> loadFromFileInBatches(Integer batchsize) {
    List<String> result = new ArrayList<String>();
    if (!EOF) {
      try {
        int i = 0;
        while (!EOF && i++ < batchsize) {
          String nextLine = bufferedReader.readLine();
          if (nextLine == null)
            EOF = true;
          else
            result.add(nextLine);
        }
        if (EOF) {
          bufferedReader.close();
        }
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    return result;
  }

  private class TextFileIterator implements Iterator<String> {
    private String buffer;
    
    public TextFileIterator() {
      try {
        buffer = bufferedReader.readLine();
        if(buffer == null) {
          EOF = true;
          bufferedReader.close();
        }
      }
      catch (IOException e) {
        e.printStackTrace();
      }
      
    }

    public boolean hasNext() {
      return !EOF;
    }

    public String next() {
      String result = buffer;
      try {
        buffer = bufferedReader.readLine();
        if(buffer == null) {
          EOF = true;
          bufferedReader.close();
        }
      } catch (IOException e) {
        e.printStackTrace();
      }

      return result;
    }

    public void remove() {
      // not implemented
    }

  }

  public Iterator<String> iterator() {
    return new TextFileIterator();
  }
}