#!/usr/bin/perl
# Program to automatically update .h files from .cc file
# For more info, see headergen.txt

use strict;
my $QTDIR=$ENV{'QTDIR'};
my $cppflags="-I$QTDIR/include -D__GNUC__";	#preprocessor flags

my $file_count=0;

# refresh one header
sub refresh {
 my ($name)=@_;		# Base name without extension
 my $wmessage="Parsing $name";
 my @fn=();
 my $f_c=$name.".cc";	# Name of .cc file
 my $f_h=$name.".h";	# Name of .h file
 my $realname='';	# Name of class with proper capitalization
 my $mark="__".uc($f_h)."__";
 $mark=~s/\./_/g;

 # Open C++ file
# open FC, "cpp $f_c $cppflags|";	#use preprocessor to strip comments etc ...
 open FC, "cat $f_c|";	#do not use preprocessor
 while (my $line=<FC>) {
  next if ($line=~/^\s*$/);	# Empty line
  next if ($line=~/^#/);	# Line with preprocessor directive
  if ($line=~/\/\*\*/) {	# Line contain /** style doxygen comment
   while (!($line=~/\*\//)) {	# Read until first "*/" comment end
    my $lw=<FC>;
    $line.=$lw;
    last if ($lw eq '');	# End of file
   }
   $line=~s/\/\*\*[\x00-\xff]*?\*\///mg;	# Weed the comment out
  }
  $line=~s/^\s+//g;
  if ($line=~/(^|\s)${name}::/i) {	# Line contain class name (assuming filename=classname, except for case)
   while (!($line=~/\{/)) {	# Read until first "{" bracket
    my $lw=<FC>;
    $line.=$lw;
    last if ($lw eq '');	# End of file
   }
   $line=~s/\n/ /mg;		# Newlines to space
   $line=~s/\s*\{.*\s*//g;	# strip bracket {
   $line.=';';			# Append semicolon ;
   $line=~/::(~?\w+)/;		# get name of method
   my $func=$1;			# Name of method
   if ($line=~s/(${name}):://i) {
    $realname=$1;		# Set correct name of class when we found it
   }
   # Convert commented initializers ( "/*=something*/" --> "=something" )
   $line=~s|\s*/\*=\s*(.*?)\*/\s*|=\1|g;
   # Strip out calling of superclass constructor(s) "X() : Y();" -> "X();"
   # up to one extra level of brackets can occur in calling of constructor, like "X(x):Y(f(x))"
   $line=~s/([^:])\s*:\s*[a-zA-Z_][a-zA-Z_0-9]*\s*\(([^()]*|\([^()]*\))*\)(\s*,\s*[a-zA-Z_][a-zA-Z_0-9]*\s*\(([^()]*|\([^()]*\))*\))*\s*;$/\1;/;
   # Remove "unused" attribute
   $line=~s/__attribute__\(\(unused\)\)\s*//g;
   # Add to line with functions found
   push @fn,$line;
#   print $func." -> ".$line."\n";
  } 
 }
 close FC;
 $file_count++;
 if (!@fn) { #nothing that can be added to headers in this file -> return
  print "$wmessage .. no headers\n";
  return;
 }
 $wmessage.="\n";

 # Open header file
 open FH, "<$f_h";
 my $head='';
 my $head_h='';
 while (my $line=<FH>) {
  $head.=$line;
  # Look for class definition
  if ($line=~/class\s+$name(\s+|:|$)/i) {
   #split the content into two pieces ("before class definition" and "inside class definition and further")
   $head_h=$head;$head='';
  }
 }
 if ($head_h=~/^$/) {
  # No class defined in header -> create one
  $head_h="$head\n\nclass $realname {\n";
  $head="};\n";
 }
 close FH;

 my $added=0;
 my $addedh=0;
 # Look for include guards
 if (!($head_h=~/$mark/)) {
  $head_h="#ifndef $mark\n#define $mark\n".$head_h;
  $head.="#endif\n";
  $addedh=1;
 }
 my $out='';
 $out.=$head_h;
 # For each function found in .cc file
 foreach my $i (@fn) {
  # Is present in header?
  my $idx=0;
  my $c='';
  for(;;) {
   $idx=index($head,$i,$idx);
   last if ($idx<=0);
   #check for character before definition -> must be whitespace
   $c=substr($head,$idx-1,1);
   if ($c=~/\S/) {	#non-whitespace -> Invalid match
    my $idxo=$idx;
    $idx=index($head,$i,$idx+1);
    last if ($idx<=0);
    next;
   }
   last;
  }
  if ($idx==-1) {
   if (!$added) {$out.="//ADDED functions begin\n";}
   $out.=" $i\n";$added++;
  }
 }
 if ($added) {$out.="//ADDED functions end\n";}
 $out.=$head;
 # Write modifications, if any ...
 if ($added || $addedh) {
  if ($added) { print "$wmessage (added $added function(s) to $f_h)\n"; $wmessage='';}
  if ($addedh) { print "$wmessage (added include guards to $f_h)\n"; $wmessage='';}
  # Backup the original file
  rename($f_h,$f_h.".old");
  # Write modified header file
  open FH, ">$f_h";
  binmode FH;
  print FH $out;
  close FH;
 }
}

my @ignore=();
open IGN, "<.headergen.ignore";
while (my $l=<IGN>){
 $l=~s/^\s+//mg;
 $l=~s/\s+$//mg;
 push @ignore,$l;
}
my $ign=join('|',@ignore);
#print "Ignoring: $ign\n";
close IGN;

opendir (DH,".") || die "Cannot open current directory";
while (my $s=readdir(DH)) {
 if ($ign=~/./ && $s=~/$ign/) {
#  print "Ignoring $s\n";
  next;
 }
 next if (!($s=~/(.*)\.cc$/i));
 refresh($1);
}
print "Parsed $file_count file(s)\n";
closedir DH;