#!/usr/bin/perl -w

use strict;
use File::Basename;
use Getopt::Long;
use Date::Format;
use Time::HiRes qw( usleep );
use DBI;

# +---------------------------------------------------------------------------+
# !          SUBS DECLARATION                                                 !
# +---------------------------------------------------------------------------+
sub usage(@);
sub findWord(@);
sub findSubWord(@);
sub dbConnect(@);
sub log_message(@);
sub clean_and_exit(@);

# +---------------------------------------------------------------------------+
# !          SETTINGS                                                         !
# +---------------------------------------------------------------------------+
select STDOUT;
$| = 1;

my $MAIN_PROG_DDBNAME = "scrabble";
my $MAIN_PROG_DBUSER = "mediabot";
my $MAIN_PROG_DBPASS = "*****";
my $MAIN_PROG_DBHOST = "localhost";
my $MAIN_PROG_DBPORT = "3306";

my $debug=0;
my $stop_length = 1;
my $max_length = 16;
my $max_result = 20;
my $nbHitCache = 0;
my $nbHitDictionary = 0;
my $nbHitSearchCache = 0;
my $nbSearch = 0;

# Check parameters
GetOptions (
        '--debug' => \$debug,
        );

unless ( $#ARGV >= 0 ) {
    usage "Invalid argument";
}

#print "Length : " . length($ARGV[0]) . "\n";

if ( length($ARGV[0]) > $max_length ) {
    usage "Longueur maximum : $max_length";
}

my $word = $ARGV[0];
$word =~ tr/a-z/A-Z/;
my @sortedLetters = sort(split(//,$word));

my $startedTime = time;
#print "Results Picking : $word Sorted : " . join(" ",@sortedLetters) ." (len=". ($#sortedLetters+1) ." min=$stop_length)\n";
my $sortedParam = join("",@sortedLetters);

my %results;
my %wordCache;
my %searchCache;
my $len = length($sortedParam);

my $dbh = dbConnect($MAIN_PROG_DDBNAME,$MAIN_PROG_DBHOST,$MAIN_PROG_DBPORT,$MAIN_PROG_DBUSER,$MAIN_PROG_DBPASS);

# Look for the whole word
my $foundWord = undef;
if (defined($foundWord = findWord($sortedParam))) {
    $results{$len} = $foundWord;
    if ($debug) { print "Results($len) : $foundWord\n"; }
}
else {

    # Search a sub word
    my $current_len = $len -1;
    findSubWord($sortedParam,$current_len);
}

# Display results
foreach my $l (sort {$b <=> $a} (keys( %results ))) {
    print "Les mots les plus longs étaient  : " . $results{$l} . " ($l)\n";
    clean_and_exit(undef,0);
}

my $duration = time - $startedTime;
#print "Results search completed in $duration secs. (Searches : $nbSearch, Dictionary hits : $nbHitDictionary , Cache hits : $nbHitCache Cache search hits : $nbHitSearchCache)\n";

print "Je n'ai pas trouvé de mots\n";
clean_and_exit(undef,0);

# +------+
# ! SUBS !
# +------+

# Display errors and usage
sub usage(@) {
    my @errMsg = @_;
    if ( $#errMsg >= 0 ) {
        print "Error: " . join (" ",@errMsg) . "\n";
    }
    print "Usage: " . basename($0) . " <letters>\n";
    exit 1;
}

# Find sorted word in dictionary
sub findWord(@) {
    my ($sortedWord) = @_;

    #Check if word has been previously searched

    unless ( defined($wordCache{$sortedWord}) && $wordCache{$sortedWord} ) {
        ## Open dictionary
        $nbHitDictionary++;
        $wordCache{$sortedWord} = 1;
        my $sWordSearchQuery = "SELECT * from DICT where sorted='$sortedWord'";
        my $sth = $dbh->prepare($sWordSearchQuery);
        unless ($sth->execute) {
            log_message("SQL Error : " . $DBI::errstr . " Query : " . $sWordSearchQuery);
        }
        else {
            my $foundWords = undef;
            while (my $ref = $sth->fetchrow_hashref()) {
                my $realWord = $ref->{'word'};
                $realWord =~ tr/A-Z/a-z/;
                #print "Results progress found(" . length($realWord) . "): $realWord  [" . (time - $startedTime)  . " secs]\n";
                $foundWords .= " $realWord";
            }
            return $foundWords;
        }
    }
    else {
        $nbHitCache++;
        if ($debug) { print "Cache hit for $sortedWord !\n"; }
    }
    return undef;
}

# Find sublength words long in $sLetters
sub findSubWord(@) {
    my ($sLetters,$sublength) = @_;
    $wordCache{$sLetters . $sublength} = 1;
    $nbSearch++;
    my $len = length($sLetters);
    my $drop_letters= $len - $sublength;

    my $j;
    for ($j=0;$j<$len;$j++) {
    my $sortedWord = "";
    my $leftWord = substr($sLetters,0,$j);
    if (defined($leftWord)) {
        $sortedWord = $leftWord;
    }
    my $rightWord = substr($sLetters,$j+1,$len);
    if (defined($rightWord)) {
      $sortedWord .= $rightWord;
    }
    if ($debug) { print "\t$sortedWord\n"; }
    my $foundWord;
    if (defined($foundWord = findWord($sortedWord))) {
      unless (defined($results{($len-1)})) {
        $results{($len-1)} = $foundWord;
        return 1;
      }
      else {
          $results{($len-1)} .= " $foundWord";
          return 1;
      }
    }
    if ( (length($sortedWord) - 1) >= $stop_length ) {
        unless (defined($wordCache{$sortedWord . (length($sortedWord) - 1)}) && $wordCache{$sortedWord . (length($sortedWord) - 1)}) {
            if (defined($results{length($sortedWord) - 1})) {
                my @tResults = split(/ /,$results{length($sortedWord) - 1});
                if ( $#tResults < ($max_result-1) ) {
                    findSubWord($sortedWord,length($sortedWord) - 1);
                }
            }
            else {
                findSubWord($sortedWord,length($sortedWord) - 1);
            }
        }
        else {
            if ($debug) { print "Search Cache hit for " . $sortedWord . (length($sortedWord) - 1) . " !\n"; }
            $nbHitSearchCache++;
        }
    }
    }

    return 1;
}

sub dbConnect(@) {
    my ($dbname,$dbhost,$dbport,$dbuser,$dbpasswd) = @_;
    my $connectionInfo="DBI:mysql:database=$dbname;$dbhost:$dbport";   # Database connection string
    my $dbh;                                                                 # Database handle

    if ($debug > 0) { log_message("DEBUG1: Connecting to Database : " . $dbname); }

    unless ( $dbh = DBI->connect($connectionInfo,$dbuser,$dbpasswd) ) {
            log_message("DBI Error : " . $DBI::errstr);
            return undef;
    }
    if ($debug > 0) { log_message("DEBUG1: Connected to $dbname."); }
    return $dbh;
}

sub log_message(@) {
    my ($sMsg) = @_;
    my $sDisplayMsg = time2str("[%d/%m/%Y %H:%M:%S]",time) . " $sMsg\n";
    select STDOUT;
    $|=1;
    print $sDisplayMsg;
    #print $sDisplayMsg;
}

sub clean_and_exit(@) {
    my ($conn,$iRetValue) = @_;
    #log_message("Cleaning and exiting...");
    if(defined(fileno(LOG))) { close LOG; }
    $dbh->disconnect();
    exit $iRetValue;
}