File Coverage

blib/lib/Device/KeyStroke/Mobile.pm

Criterion	Covered	Total	%
statement	27	30	90.0
branch	4	8	50.0
condition			n/a
subroutine	4	5	80.0
pod	1	1	100.0
total	36	44	81.8

package Device::KeyStroke::Mobile;

use strict;
use vars qw($VERSION @EXPORT $KeyMapping);
$VERSION = 0.01;

require Exporter;
*import = \&Exporter::import;
@EXPORT = qw(calc_keystroke);

$KeyMapping = {
    1 => '',
    2 => 'ABC',
    3 => 'DEF',
    4 => 'GHI',
    5 => 'JKL',
    6 => 'MNO',
    7 => 'PQRS',
    8 => 'TUV',
    9 => 'WXYZ',
    '*' => '.-@/',
    0 => '',
    '#' => '',
};

sub _croak { require Carp; Carp::croak(@_) }

sub calc_keystroke {
    my $text = uc(shift);
    my $lookup = _build_lookup($KeyMapping); # XXX need cache? but
                                             # mapping can be modified ...

    my $typing_times = 0;
    my $prev = '';
    for my $i (0 .. length($text) - 1) {
	my $char = substr($text, $i, 1);
	my $table = $lookup->{$char}
	    or _croak("don't know how to type $char");
	my($time, $keypad) = @{$lookup->{$char}};
	$typing_times += $time;
	$typing_times++  if $prev eq $keypad; # for ">" key
	$prev = $keypad;
    }

    return $typing_times;
}

sub _build_lookup {
    my $mapping = shift;
    my %lookup;
    while (my($key, $values) = each %$mapping) {
	for my $len (1..length($values)) {
	    my $char = substr($values, $len - 1, 1);
	    if (exists $lookup{$char}) {
		next if $len > $lookup{$char}->[0]; # already has shorter one
	    }
	    $lookup{$char} = [ $len, $key ];
	}
    }
    return \%lookup;
}

1;
__END__