#!/usr/bin/perl -w

use strict;

$|=1;

die unless @ARGV == 1;
my ($file) = @ARGV;
die if $file =~ m{^-};

open STDIN, "<", $file or die "$file $!";
open L, "expand -t4 |" or die $!;
our (@l) = <L>;
$?=0; $!=0; close L or die "$? $!";

unshift @l, '';

my $block_start = 0;
my $heading;

foreach my $i (0..$#l) {
  $_ = $l[$i];
  if (m{^\`\`\`}) {
    if ($block_start) {
      $block_start = 0;
    } else {
      $block_start = $i + 1;
    }
  }

  if (!$block_start && m{^\#+ (\S.*)\n}) {
    $heading = $1;
  }

  if (defined($block_start) && m{^(total +)(\d+)\s}) {
    my ($lhs, $exp) = ($1, $2);
    my $got = 0;
    foreach my $j ($block_start .. ($i-1)) {
      $_ = $l[$j];
      my $earlier = length($lhs) - 1;
      next if m{^\#};
      next unless length > $earlier+1;
      die "$file:$j: ($i): $_ ?" unless m{^.{$earlier} (\S+)\s};
      my $here = $1;
      next unless $here =~ m{^[-+]?\d+$};
      $got += $here;
    }
    my $delta = $exp - $got;
    print "$file: checking total: $heading\n";
    if ($delta) {
      print STDERR "$file:$i: expected $exp but got $got, spend $delta\n";
    }
    next;
  }
}