#!/usr/bin/perl
# wikipedialookup - conveniently look up articles in the Wikipedia fro
+m
# the command line. Version 0.2

use strict;
use warnings;
use File::Copy;
use File::Spec;
use Getopt::Long;
use WWW::Wikipedia;
##################################################
use constant VERSION=> "0.2";
use constant DEBUGGING=> 1;

##################################################
# Subroutine prototypes
##################################################
sub display_long;
sub display_short;
sub display_help;
sub display_version;
sub make_conf;
sub get_conf;
sub chk_env;
sub clean_up;
##################################################

$SIG{INT} = \&clean_up;# clear tmp folder if SIGINT is received

# following are the language codes that are currently recognized by
# the Wikipedia. We need this list to display it on demand in the
# configuration dialog
my @lcodes = qw/ af ar bg bn ca cs cy da de el en eo es et fa fi fr fy
 he hi hu ia id it ja ko la ln ml ms nl no oc pl pt ro
 ru sk sl sq sr sv ta th uk ur wo yi zh /;

# options that need to be implemented:
# - quick lookup: take a single arg and display short article (default
+)
# - long info   : take keyword as arg look up article disply in pager 
+or editor
# - make config : make configuration file, implement dialog. mkconf if
+ 1. start
# - clean up    : clean up temporary and permanent folders. tmp on def
+ault
# - chck duplics: check for and delete duplicates in permanent folder
# - version     : display version info
# - help        : display help

# take care of the command line options
my %options;
GetOptions (\%options, "long", "make-config", "clean-up", "language:s"
+,
       "version", "help");

my $keyword = shift;

if ((keys %options == 0) && (! $keyword)) {
    die "Usage: $0 keyword [options]. Type $0 --help for more informat
+ion.\n";
}
if (($options{long}) && (! $keyword)) {
    die "Usage: $0 keyword [options]. Type $0 --help for more informat
+ion.\n";
}
if (($options{language}) && (! $keyword)) {
    die "Usage: $0 keyword [options]. Type $0 --help for more informat
+ion.\n";
}

# read in configuration
my %conf = get_conf ("wikipedialookup.conf");

# for portability's sake we use File::Spec to build the pathnames
# to the temporary and the permanent directory. As we store them
# in two variables here the code where these paths are actually used
# will look much less cluttered.
my $tmp_path = File::Spec->rel2abs ("tmp");
my $prm_path = File::Spec->rel2abs ("articles");
my $tmp_file = File::Spec->catfile ($tmp_path, "wikipedialookup$$");

##################################################
# MAIN
##################################################

# before we get started we need to perform some checks
if ($options{help}) {
    display_help();
    exit;
}
if ($options{version}) {
    display_version();
    exit;
}
if ($options{"make-config"}) {
    make_conf ("wikipedialookup.conf");
    exit;
}
if ($options{"clean-up"}) {
    clean_up ("all");
    exit;
}

chk_env();

# okay, ready to go...
my $wiki = WWW::Wikipedia->new (language => $options{language}
    || $conf{language});
$wiki->timeout ($conf{timeout});

# perform the search...
my $entry = $wiki->search ($keyword);

if ($options{long}) {
   if ($entry) {
my $fulltext = $entry->fulltext();
my @related  = $entry->related();
my @categories= $entry->categories();

      unless (display_long (\$fulltext, \@related, \@categories)) {
    if (@related) {
print "The keyword you provided is ambiguous: $keyword\n";
print "Please see the following articles:\n";
print "\t- $_\n"foreach @related;
    }
    else {
print "Nothing to show. This might be due to a bug. Sorry :-(\n";
    }
}
    }
    else {
print "No article found for $keyword.\n";
print "You might try to search for $keyword in another language.\n";
print "Try: $0 $keyword --language=fr e.g. to search the French\n";
print "version of Wikipedia.\n";
print "\nSorry :-(\n";
    }
}
else {
    if ($entry) {
my $text    = $entry->text();
my @related = $entry->related();
unless (display_short ($text)) {
    if (@related) {
print "The keyword you provided is ambiguous: $keyword\n";
print "Please see the following articles:\n";
print "\t- $_\n"foreach @related;
    }
    else {
print "Nothing to show. This might be due to a bug. Sorry :-(\n";
    }
}
    }
    else {
print "No article found for $keyword.\n";
print "You might try to search for $keyword in another language.\n";
print "Try: $0 $keyword --language=fr e.g. to search the French\n";
print "version of Wikipedia.\n";
print "\nSorry :-(\n";
    }
}

##################################################
# Subroutines
##################################################

##############################
sub display_long {
##############################
    my ($text, $related, $categories) = @_;
    return undef    unless $text;

    my $line = "=" x length "Entry for $keyword";

    open OUT, "> $tmp_file"    or die "Couldn't open $tmp_file: $!";
    
    print OUT $line;
    print OUT "Entry for $keyword\n";
    print OUT $line;
    print OUT "\n\n";
    print OUT $$text;
    print OUT "\n";
    print OUT "========================================\n";
    print OUT "See also the following related articles:\n";
    print OUT "========================================\n";
    print OUT "\n";
    print OUT "\t- $_\n"foreach @$related;
    print OUT "\n";
    print OUT "=================================================\n";
    print OUT "This article belongs to the following categories:\n";
    print OUT "=================================================\n";
    print OUT "\n";
    print OUT "\t- $_\n"foreach @$categories;

    close OUT;

    unless (! system $conf{editor}, $tmp_file) {
print "Couldn't exec $conf{editor}: $! Please re-run the configuration
+";
    }

    my $prm_file = File::Spec->catfile ($prm_path, "$keyword.txt");
    if (copy ($tmp_file, $prm_file)) {
print "You can find a copy of the article in $prm_file.\n";
    }
    else {
print "Couldn't copy $tmp_file to $prm_file", ": $!";
    }

    return 1;
}

##############################
sub display_short {
##############################
    my $text = shift;
    return undef    unless $text;

    if ($conf{"use_pager"} && $conf{"pager"}) {
unless (open OUT, "| $conf{pager}") {
    warn "Couldn't pipe to $conf{pager}", ": $!";
    warn "Will print to STDOUT\n";

    *OUT = *STDOUT;
}
    }
    else {
*OUT = *STDOUT;
    }

    print OUT "=" x length $keyword;
    print OUT "\n";
    print OUT "$keyword\n";
    print OUT "=" x length $keyword;
    print OUT "\n";
    print OUT $text;
    print OUT "\n";

    eval { close OUT; };

    return 1;
}

##############################
sub chk_env {
##############################
    mkdir "tmp",      0755    unless -e "tmp";
    mkdir "articles", 0755    unless -e "articles";

    make_conf ("wikipedialookup.conf")    unless -e "wikilookup.conf";
}

##############################
sub make_conf {
##############################
    my $file = shift;
    my %conf;

    open CONF, "> $file"or die "Couldn't open $file: $!";

    print "Please specify some information on how to run wikilookup.\n
+";
    print "\nDefault language (default is 'en', type 'all' to see\n";
    print "all available language codes).\n";
    print "\t[en]: ";
    chomp (my $choice = <STDIN>);

    if ($choice eq "all") {
        print "$_\t"        foreach @lcodes;
        print "\n[en]: ";
        chomp ($choice = <STDIN>);
    }   
    elsif ($choice eq "") {
        $choice = "en";
    }   
    $conf{language} = $choice;

    print "Please enter the name of the editor you want to use:\n";
    print "\t[vim]: ";
    chomp ($choice = <STDIN>);
    $choice = "vim"    unless $choice;
    $conf{editor} = $choice;

    print "Do you want to use a pager to display short articles?";
    print "\t[n]: ";
    chomp ($choice = <STDIN>);
    $conf{"use_pager"} = "1"    if $choice =~ /^y/i;
    if ($conf{"use_pager"}) {
print "Please enter the name of your pager:\n";
print "\t[less]: ";
chomp ($choice = <STDIN>); 
$choice = "less"    unless $choice;
$conf{pager} = $choice;
    }

    print "After how many seconds shall the request time out?\n";
    print "\t[12]: ";
    chomp ($choice = <STDIN>);
    unless (($choice =~ /^\d+$/) || ($choice eq "")) {
print "Invalid timeout: $choice. Will use 12.\n";
$choice = 12;
    }
    $conf{timeout} = $choice;
    print "Thanks, that's all for now.\n";

    print CONF "$_=$conf{$_}\n"    foreach sort keys %conf;

    close CONF;

    %conf;
}

##############################
sub get_conf {
##############################
    my $file = shift;
    my %conf;

    unless (open CONF, $file) {
%conf = make_conf ($file);
return %conf;
    }

    while (<CONF>) {
chomp;
my ($key, $value) = split /=/;
$conf{$key} = $value;
    }

    eval { close CONF; };

    %conf;
}

##############################
sub clean_up {
##############################
    my $all = shift;
    # we need a trailing slash (colon/backslash) for the glob later
    $tmp_path = File::Spec->catfile ($tmp_path, "");
    $prm_path = File::Spec->catfile ($prm_path, "");

    eval { unlink glob "$tmp_path*.tmp" };
    warn "Error while cleaning up: $@"if $@;
    if ($all) {
eval {
    unlink glob "$tmp_path*";
    unlink glob "$prm_path*";
};
warn "Error while cleaning up: $@"if $@;
    }
}

##############################
sub display_help {
##############################
    print <<EOF;
wikipedialookup - a small command line tool to quickly look up entries
+ in the
     Wikipedia.

Usage: $0 keyword [ --long | --make-config | --clean-up | 
    --language | --version | --help ]

    --long    Display long article, as opposed to the cut version
displayed on default.
--language    Specify language of the query in one of the
available Wikipedia language codes.
    -m    --make-configSet up a new configuration file. You will be as
+ked
to set up a new configuration file the first time
you start the program, also.
    -c    --clean-up    Delete all files from both the tmp and the per
+manent
folder. wikipedialookup automatically cleans up the
tmp folder on exit.
    -v    --version    Display version information.
    -h    --help    Show this help screen.

Please send bug reports to: sven-thorsten.fahrbach\@gmx.net
EOF
    
}

##############################
sub display_version {
##############################
    print "wikipedialookup version ", VERSION, "\n";
    print "\nThis program may be used and redistributed under the term
+s\n";
    print "of the Free BSD license.\n";
    print "\nPlease send bug reports to: sven-thorsten.fahrbach\@gmx.n
+et\n";
}
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