1#!/usr/local/bin/ruby
2
3# quotes.rb
4#
5#  Copyright (C) 2001-2011 Free Software Foundation, Inc.
6#
7#  Copying and distribution of this file, with or without modification,
8#  are permitted in any medium without royalty provided the copyright
9#  notice and this notice are preserved.
10#
11#  Contact: bug-gnu-chess@gnu.org
12
13# This script replaces inner double quotes in fi by single quotes and writes
14# the result on fo. This is necessary because command 'book add' does not
15# accept more than two matching double quotes in PGN files.
16
17# The program expects exactly two arguments in the command-line.
18# The first argument is the name of the input file, i.e. the file that is
19# going to be processed.
20# The second argument is the name of the output file, i.e. the file that will
21# be written as a result of processing the input file.
22
23# Check the number of command-line arguments: if other than two, display the
24# usage message and exit.
25if ARGV.size != 2 then
26  puts "Usage: ./quotes <pgn_file_input> <pgn_file_output>"
27  exit
28end
29
30# 'fiName' takes the first command-line argument, i.e. the input file name
31fiName = ARGV[0]
32
33# 'foName' takes the second command-line argument, i.e. the output file name
34foName = ARGV[1]
35
36# If the input does not exists, print an error message and exit.
37if not File.exists? fiName then
38  puts "File #{fiName} does not exist."
39  exit
40end
41
42# If the input and output file names are identical, print an error message
43# and exit.
44if foName == fiName then
45  puts "Provide different input and output file names"
46  exit
47end
48
49# If the output file already exists, ask the user if she or he wants to
50# replace it. Repeat the question in an infinite loop until the user enters
51# a valid answer:
52# if the user answers 'y' or 'Y', the program will continue;
53# if the user answers 'n' or 'N', the program will exit.
54if File.exists? foName then
55  answer = ""
56  while answer != "y" and answer != "n"
57    puts "File #{foName} already exists. Replace it (y/n)?"
58    answer = STDIN.gets.chop
59    answer.downcase!
60  end
61  if answer == "n" then
62    exit
63  end
64end
65
66# Open the input file in read-only mode
67fi = File.new( fiName, 'r' )
68
69# Open the output file in read-write mode
70fo = File.new( foName, 'w' )
71
72# Loop over each line of the input file
73fi.each {|line|
74
75  nQuotes = line.count( '\"' )  # Get the number of double quotes that are
76                                # present in the line.
77  oLine = ''     # Initialise the output line
78  oLine << line  # By default, the output line is equal to the input line
79
80  # If the number of double quotes in the line is greater than 2, the output
81  # line requires special processing.
82  if nQuotes > 2 then
83
84    # The line will be scanned character by character...
85
86    nq = 0  # Initialize the count of double quotes in the line.
87    oLine = ''  # Overrides previous value of the output line
88
89    # Loop over each character of the line
90    line.each_char {|c|
91      # If the character is a double quote, do special processing;
92      # otherwise, append it to the output line.
93      if c == "\"" then
94        # Two special cases are considered (enough to cover book_1.01.pgn):
95        #   a) 3 double quotes => replace the 2nd double quote by a single quote
96        #   b) 4 double quotes => replace the 2nd and 3rd double quotes  by a
97        #      single quote
98        # Otherwise, append the character to the output line.
99        if ( nQuotes == 3 and nq == 1 ) or ( nQuotes == 4 and ( nq == 1 or nq == 2 ) ) then
100          oLine << '\''
101        else
102          oLine << c
103        end
104        nq += 1
105      else
106        oLine << c
107      end
108    }  # End of looping over the characters of a line
109
110  end
111
112  fo.puts oLine  # Write output line to the output file
113
114}  # End of looping over the lines of the input file
115
116# Close the output file
117fo.close
118
119# Close the input file
120fi.close
121