use strict;
use Test::More;
use Math::Round;

my $tests = [
             [       '0', 43,         '43',   'Can go past one digit.'],
             [       '0', 4.4003,     '4',      'Rounds down to 4'],
             [       '0', 4.5003,     '5',      'Rounds up to 5'],
             [       '0', 400.5003,   '401',      'Rounds up to 5'],
             [       '0', -34,        '-34', 'no change to negative values'],
             [      '#0', 4.5003,     '5',      'Rounds up to 5'],
             [      '#0', 99.5003,    '100',  'rounds up to 100'],
             [      '#0', 43,         '43',   'as expected'],
             [      '#0', 4,          '4',    ''],   
             [      '#0', 3.45E-4,    '0',     'exponent negative rounded to zero'],
             [      '#0', 3.45E+4,    '34500', 'exponent real ok.'],
             [      '00', 43,         '43', ''],
             [      '00', 3,         '03', ''],
             [      '00', 999,         '999', ''],
             [      '00', 43,         '43', ''],
             [     '0.0', 43.333,       '43.3', ''],
             [     '0.0', -43.333,       '-43.3', ''],
             [     '0.0', 44.35,       '44.4', 'Floating rounded up.'],
             [   '#0.00', 43.3,       '43.30', ''],
             [   '#0.00', 3.3,        '3.30', ''],
             [   '#0.00', 43.3,       '43.30', ''],
             [    '0.00', 43.3,       '43.30', ''],
             [    '0.00', 43.3,       '43.30', ''],
             [    '0.00', 43.3,       '43.30', ''],
             [    '0000', 43,         '0043', ''],
             [ '##0.000', 43.3,       '43.300', ''],
             [   '0.000', 43.3,       '43.300', ''],
             [   '00.00', 43.3,       '43.30', ''],
             [   '000.0', 43.3,       '043.3', ''],
             [  '0.0000', 43.3,       '43.3000', ''],
             [  '000.00', 43.3,       '043.30', ''],
             [  '000000', 43,         '000043', ''],
             ['000.0000', 43.3,       '043.3000', ''],
             ['0.00E-00', 43.3,       '4.33E+01', ''],
             ['0.00E+00', 43.3,       '4.33E+01', ''],
            ];

plan tests => scalar(@$tests);

foreach my $test (@$tests)
{
  my $result = formatString($test->[1], $test->[0]);
  printf("Pattern:[%s] Value:[%s], ExpectedResult:[%s] Result:[%s]\n", @{$test}[0 .. 2], $result);
  is($result, $test->[2], $test->[3]);
}

sub formatString
{
  my $value = shift;
  my $text = shift;
  my $debug = shift;
  my $workingValue = $value;
  #  # will either be a digit or not.  It doesn't appear to have any affect on the result.
  #
  #  0 will be either 0 or a digit.
  #  0.00E-00 is a scientific example.
  #
  $text =~ s/^#+//;             # # doesn't do much at all.

  my $beforeDotRE     = qr{^([\d]+)}; # stuff before the decimal (if there is one)
  my $afterDotRE      = qr{\.(\d*)(E[+-](\d+))?$}; # stuff after the decimal. 
  my $scientificRE    = qw{E[+-](\d+)$}; # Scientific ending.

  my $textLength = length($text);

  my $beforeDot ='';
  my $beforeDotLen =0;
  if($text =~ m{$beforeDotRE})
  {
    $beforeDot = $1;
    $beforeDotLen = length($beforeDot);
  }

  my $afterDot ='';
  my $afterDotLen =0;
  if($text =~ m{$afterDotRE})
  {
    $afterDot = $1;
    $afterDotLen = length($afterDot);
  }

  my $scientific ='';
  my $scientificLen =0;
  if($text =~ m{$scientificRE})
  {
    $scientific = $1;
    $scientificLen = length($scientific);
  }

  if($debug)
  {
    printf "Done Analyzing:[%s]\n", $text;
    printf "Format Length: [%d]\n", $textLength;
    printf "    beforeDot: [%s]\n", $beforeDot;
    printf "     afterDot: [%s]\n", $afterDot;
    printf "   scientific: [%s]\n", $scientific;
  }

  my $spec;
  if ($afterDotLen <= 0)
  {
    # if the value is a float of some kind.  Then it needs
    # to get rounded.
    $workingValue = Math::Round::round($value);
    # this is some kind of integer number.
    $spec = sprintf('%%0%d.%dd', $textLength, $textLength);
  } 
  elsif ($scientificLen <= 0)
  {
    # this is a floating point number
    $spec = sprintf('%%0%d.%df', $textLength, $afterDotLen);
  } 
  else
  {
    # this is a scientific number.
    $spec = sprintf('%%0%d.%dE', $textLength, $afterDotLen);
  }

  my $result = sprintf($spec, $workingValue);
  if($debug)
  {
    print  "     Original: [$value]\n";
    print  "         Spec: [$spec]\n";
    print  "Working Value: [$workingValue]\n";
    print  "       Result: [$result]\n\n";
  }

  return $result;
}