#!/usr/bin/perl
# Script for extracting documentation out of header files
# (c) 2008 Michal Vaner <vorner@ucw.cz>

use strict;
use warnings;

my( $inname, $outname, $depname, $basedir, $defdump ) = @ARGV;
if( defined $inname ) {
	open IN, $inname or die "Could not read $inname ($!)\n";
} else {
	open IN, "<&STDIN" or die "Could not read stdin ($!)\n";
}
if( defined $outname ) {
	open OUT, ">$outname" or die "Could not write $outname ($!)\n";
} else {
	open OUT, ">&STDOUT" or die "Could not write to stdout ($!)\n";
}
my $hasdump;
if( defined $defdump ) {
	open DUMP, ">$defdump" or die "Could not write definition dump $defdump ($!)\n";
	$hasdump = 1;
}

sub detect( $ ) {
        ( $_ ) = @_;
	return( 'struct', 1, $1, "typedef struct { ... } $1;" ) if /^\s*typedef\s+struct\s*{.*}\s*(\w+)\s*;\s*$/s;
	return( 'enum', 1, $1, "typedef enum { ... } $1;" ) if /^\s*typedef\s+enum\s*{.*}\s*(\w+)\s*;\s*$/s;
        my $l = length;
        s/\n.*//s;
        return( 'struct', 0, $1, $_ ) if /struct\s+(\w+)\s+{/;
        return( 'enum', 0, $1, $_ ) if /enum\s+(\w+)\s+{/;
        if( $l > length ) {
                warn( "Unknown statement $_\n" );
                return( '', 0, $_, $_ );
        }
        return( 'def', 0, $1, $_ ) if /#define\s+(\w+)/;
        return( 'fun', 1, $2, $1 ) if /^(.*?(\w+)\([^{]*\)[^{]*)/;
	return( 'type', 1, $1, $_ ) if /^\s*typedef.*?(\w+);/;
        return( 'var', 1, $1, $_ ) if /\s(\w+);/;
        warn( "Unknown statement $_\n" );
        return( '', 0, $_, $_ );
}

my @deps;
my $id = 0;

sub formatNote( $$ ) {
	my( $head, $comment ) = @_;
	$head =~ s/(\S)[ ]+/$1 /g;
	print OUT "\n";
	print OUT "''''\n";
	chomp $head;
        my( $type, $semicolon, $name, $oneline ) = detect( $head );
	$oneline =~ s/\s+$//;
	$oneline =~ s/;?$/;/ if( $semicolon );
        $head =~ s/;?\s*$/;/ if( $semicolon );
	$head =~ s/(\.\.\.)/\\$1/g;
	print OUT "[[${type}_$name]]\n";
	$head = $oneline if $type eq 'fun';#Remove { from inline functions
	print OUT "..................\n";
	print OUT "$head\n";
	print OUT "..................\n\n";
	if( $hasdump ) {
		print DUMP "$outname,${type}_$name,$type,$name,$oneline\n";
		$id ++;
	}
	print OUT "$comment\n\n";
}

sub process( $ ) {
	my $file = shift;
	open FILE, $file or die "Could nod read $file ($!)\n";
	my $line;
	my $active;
	my $verbatim;
	my $buff;
	my $head;
	my $struct;
	while( defined( $line = <FILE> ) ) {
		chomp $line;
		if( $struct ) {
			$head .= "\n".$line;
			if( $line =~ /}/ ) {
				formatNote( $head, $buff );
				$struct = 0;
				$buff = undef;
				$head = undef;
			}
		} elsif( $verbatim ) {
			if( $line =~ /\*\// ) {
				$verbatim = 0;
				print OUT "\n";
			} else {
				$line =~ s/^\s*\* ?//;
				print OUT "$line\n";
			}
		} elsif( $active ) {
			if( $line =~ /\*\// ) {
				$active = 0;
			} else {
				$line =~ s/^\s*\* ?//;
				$buff .= "$line\n";
			}
		} else {
			if( ( $line =~ /\S/ ) && ( defined $buff ) ) {
				if( $line =~ /\(/ || $line !~ /{/ ) {
					$_ = $line;
					s/^\s*\s?//;
					s/\/\/.*//;
					s/\/\*.*?\*\///gs;
					formatNote( $_, $buff );
					$head = undef;
					$buff = undef;
				} else {
					$head = $line;
					$struct = 1;
				}
			} elsif( ( $buff ) = ( $line =~ /\/\*\*\*(.*)\*\*\*\// ) ) {
				$buff =~ s/\s?//;
				print OUT "$buff\n\n";
				$buff = undef;
			} elsif( ( $head, $buff ) = ( $line =~ /^(.*)\/\*\*(.*)\*\*\// ) ) {
				$buff =~ s/^\s*//;
				$buff =~ s/\s*$//;
				if( $head =~ /\(/ || $head !~ /{/ ) {
					$head =~ s/^\s*//;
					$head =~ s/\/\*.*?\*\///gs;
					formatNote( $head, $buff );
					$head = undef;
					$buff = undef;
				} else {
					$struct = 1;
				}
			} elsif( $line =~ /\/\*\*\*/ ) {
				$verbatim = 1;
			} elsif( $line =~ /\/\*\*/ ) {
				$active = 1;
			}
		}
	}
	close FILE;
}

my $line;
while( defined( $line = <IN> ) ) {
	chomp $line;
	if( my( $fname ) = ( $line =~ /^!!\s*(.*\S)/ ) ) {
		$fname = "$basedir/$fname" if( ( $fname !~ /^\// ) && defined $basedir );
		process( $fname );
		push @deps, $fname;
	} else {
		print OUT "$line\n";
	}
}

if( defined $depname ) {
	open DEP, ">>$depname" or die "Could not write dep file $depname ($!)\n";
	print DEP "$outname:";
	print DEP " $_" foreach( @deps );
	print DEP "\n";
	if( $hasdump ) {
		print DEP "$defdump:";
		print DEP " $_" foreach( @deps );
		print DEP "\n";
	}
	close DEP;
}

close IN;
close OUT;
close DUMP;