/*

  * Copyright (c) 2004 International Decision Systems, Inc.  All Rights Reserved.

  *

  * By using this Software, You acknowledge that the Software is a valuable asset

  * and trade secret of either International Decision Systems, Inc. ("IDSI") or a

  * third party supplier of IDSI and constitutes confidential and proprietary

  * information.

  *

  * NEITHER IDSI NOR ANY AGENT OR PERSON ACTING FOR OR WITH IDSI HAS MADE OR DOES

  * MAKE ANY STATEMENTS, AFFIRMATIONS, REPRESENTATIONS OR WARRANTIES WHATSOEVER

  * TO YOU, WHETHER EXPRESS OR IMPLIED, AS TO THE SOFTWARE, THE QUALITY OR

  * CONDITION OF THE SOFTWARE, OR THE OPERATING CHARACTERISTICS OR RELIABILITY OF

  * THE SOFTWARE, OR ITS SUITABILITY FOR ANY GENERAL OR PARTICULAR PURPOSE, OR AS

  * TO ANY OTHER MATTER WHATSOEVER; ANY AND ALL OTHER WARRANTIES INCLUDING

  * WITHOUT LIMITATION ANY WARRANTIES IMPLIED BY LAW, SUCH AS THE IMPLIED

  * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND TITLE,

  * USE AND NON-INFRINGEMENT; ARE HEREBY EXPRESSLY DISCLAIMED AND EXCLUDED.

 */

 package net.sourceforge.addam.impexp.csv;

 import java.io.BufferedReader;

 import java.io.IOException;

 import java.io.Reader;

 import java.text.CharacterIterator;

 import java.text.StringCharacterIterator;

 import java.util.ArrayList;

 import java.util.List;

 /**

  * Reads CSV files according to the rules outlined on

  * <a href="http://www.creativyst.com/Doc/Articles/CSV/CSV01.htm#FileFormat">Creativyst</a>

  *

  * @author TIM3

  * @since Jul 30, 2004

  */

 public class CSVParser {

     private final BufferedReader in;

     private StringCharacterIterator lineIterator;

     private int lineNumber;

     private int charNumber;

     private int row;

     private int col;

     /**

      * creates a CSV reader according to the rules in http://www.creativyst.com/Doc/Articles/CSV/CSV01.htm

      *

      * @param in

      */

     public CSVParser(Reader in) {

         this.in = new BufferedReader(in);

         lineNumber = 0;

         row = 0;

         col = 1;

     }

     public List readLine() throws IOException, CSVFormatException {

         ArrayList list = null;

         if (nextLine()) {

             list = new ArrayList();

             for (String field = readField(); field != null; field = readField()) {

                 list.add(field);

             }

         }

         row++;

         return list;

     }

     protected boolean nextLine() throws IOException {

         String line = in.readLine();

         lineIterator = null;

         lineNumber++;

         charNumber = 0;

         if (line != null) {

             lineIterator = new StringCharacterIterator(line);

             return true;

         }

         return false;

     }

     /**

      * reads a string array from a record, which may appear on one or more lines

      *

      * @return

      */

     protected String readField() throws IOException, CSVFormatException {

         String returnValue = null;

         // the implementation is NOT PRETTY, but it does the trick; it was built

         // iteratively with unit tests; if someone can find a more elegant

         // way to do this then I'd love to hear it

         boolean inQuotes = false; // handles how to read each character

         boolean currentValueQuoted = false; // handles how to process values

         StringBuffer buf = new StringBuffer();

         if (lineIterator != null) {

             while (returnValue == null) {

                 char c = (charNumber == 0) ? lineIterator.current() : lineIterator.next();

                 charNumber++;

                 // first handle quoted multi-line item (so we can reset c if necessary)

                 if (inQuotes && c == CharacterIterator.DONE) {

                     // go to next line and reset c

                     if (nextLine() == false) {

                         throw new CSVFormatException("quoted multi-line item doesn't end", lineNumber, charNumber);

                     }

                     c = lineIterator.current();

                     buf.append('\n');

                     charNumber++;

                 }

                 char peek = lineIterator.next();

                 lineIterator.previous(); // rewind back after the peek

                 // now deal with double quotes

                 if (c == '"' && peek == '"') {

                     // two double-quotes are always replaced by one

                     charNumber++;

                     buf.append('"');

                     lineIterator.next();

                 } else if (c == '"' && inQuotes) {

                     inQuotes = false;

                 } else if (c == '"' && !inQuotes) {

                     inQuotes = true;

                     currentValueQuoted = true;

                     // begin quote; make sure no preceding text

                     String str = buf.toString().trim();

                     if (str.length() > 0) {

                         // if preceding text is all quotes, then we likely started

                         // with some quotes, e.g. """foo""" == "foo", which is a

                         // bit confusing to the parser; simply mark the string as

                         // quoted and we'll be fine

                         for (int i = 0; i < str.length(); i++) {

                             if (str.charAt(i) != '"') {

                                 throw new CSVFormatException("invalid text before quotes:" + str, lineNumber, charNumber);

                             }

                         }

                     } else {

                         // get rid of any preceding whitespace

                         buf.setLength(0);

                         buf.append(str);

                     }

                 } else if (!inQuotes && (c == ',' || c == CharacterIterator.DONE)) {

                     String value = buf.toString();

                     if (currentValueQuoted) {

                         returnValue = value;

                     } else {

                         returnValue = value.trim();

                     }

                     if (c == CharacterIterator.DONE) {

                         lineIterator = null; // done with it -- no longer valid

                     }

                     col++;

                 } else if (!inQuotes && currentValueQuoted && c != ',') {

                     // this should only exist if text after quotes

                     if (!Character.isWhitespace(c)) {

                         throw new CSVFormatException("invalid text after quotes:" + c, lineNumber, charNumber);

                     }

                 } else {

                     buf.append(c);

                 }

             }

         }

         return returnValue;

     }

     public int getLineNumber() {

         return lineNumber;

     }

     public int getCharNumber() {

         return charNumber;

     }

     public int getRow() {

         return row;

     }

     public int getCol() {

         return col;

     }

     /**

      * @return the column as an Excel string, i.e. 1=A, 2=B, 27=AA, 28=AB, etc.

      */

     public String getExcelCell() {

         return getExcelCell(row, col);

     }

     String getExcelCell(int row, int col) {

         final char[] alphabetOne = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();

         final char[] alphabetTwo = " ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();

         int column = col - 1;

         String first = "";

         String second = "" + alphabetOne[(column % 26)];

         if (column / 26 > 0) {

             first = "" + alphabetTwo[column / 26];

         }

         return (first + second).toUpperCase() + row;

     }

 }