#!/usr/bin/perl

# Generate site V2.
# Perl script to generate my web site from a load of
# simple ascii source chunks.

use strict;

my ($page, $chunk, @pages);

# number of pages.
my $total=16;

# build index page
copy_file( "header.src", "../index.html" );
$chunk="[ <a href=\"1.html\">Next</a> ]\n";
append_chunk( "../index.html", $chunk );
append_file( "secondchunk.src", "../index.html" );
append_file( "index.src" , "../index.html" );

for(my $i=0; $i<$total; $i++ ){

  $page=$i+1;

  print"building $page \b.html\n";
  print"adding header to $page\n";
  copy_file( "header.src", "../" . $page . ".html" );
  if( $i eq "0" ){
    $chunk="[ <a href=\"index.html\">Previous</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  } else {
    $chunk="[ <a href=\"".($page-1).".html\">Previous</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  }
  $chunk="[ <a href=\"index.html\">Home</a> ]\n";
  append_chunk( "../".$page.".html", $chunk );
  if( $i ne ($total-1) ){
    $chunk="[ <a href=\"".($page+1).".html\">Next</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  }

  append_file( "secondchunk.src", "../".$page.".html" );

  print"adding body to $page\n";
  append_file( $page.".src" , "../" . $page . ".html" );

  print"adding next, previous buttons";
  $chunk="<center>\n<img src=\"hr.gif\"><br>\n";
  append_chunk( "../" . $page . ".html" , $chunk );

  if( $i eq "0" ){
    $chunk="[ <a href=\"index.html\">Previous</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  } else {
    $chunk="[ <a href=\"".($page-1).".html\">Previous</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  }
  $chunk="[ <a href=\"#top\">Top</a> ]\n";
  append_chunk( "../".$page.".html", $chunk );
  $chunk="[ <a href=\"index.html\">Home</a> ]\n";
  append_chunk( "../".$page.".html", $chunk );
  if( $i ne ($total-1) ){
    $chunk="[ <a href=\"".($page+1).".html\">Next</a> ]\n";
    append_chunk( "../".$page.".html", $chunk );
  }

  $chunk="</center>\n";
  append_chunk( "../".$page.".html", $chunk );

  print"adding footer to $page\n";
  append_file( "footer.src", "../" . $page . ".html" );

  print"adding link to index\n";
  $chunk="<li><a href=\"$page".".html\">$page</a><br>\n";
  append_chunk( "../index.html", $chunk );

}

$chunk="<center>\n<img src=\"hr.gif\"><br>\n";
append_chunk( "../index.html" , $chunk );
$chunk="[ <a href=\"1.html\">Next</a> ]\n</center>";
append_chunk( "../index.html", $chunk );

print"adding footer to index\n";
append_file( "footer.src", "../index.html" );

print "chmodding\n";
system "chmod a+r ../*";
system "chmod a+r ../graphs/*";
system "chmod a+r ../scripts/*";

# copy_file( in, out ) is a function
# to copy one file to another.
sub copy_file {
  my( $filein, $fileout ) = @_;
  open( IN, $filein ) || die "Cant open $filein for reading: $!";
  open( OUT, ">" . $fileout ) || die "Cant open $fileout for writing: $!";
  while( <IN> ){
    print OUT $_;
  }
  close( IN ) || die "Cant close $filein: $!";
  close( OUT ) || die "Cant close $fileout: $!";
}

# append_file( in, out ) is a function to
# append one file to the end of another.
sub append_file {
  my( $filein, $fileout ) = @_;
  open( IN, $filein ) || die "Cant open $filein for reading: $!";
  open( OUT, ">>" . $fileout ) || die "Cant open $fileout for appending: $!";
  while( <IN> ){
    print OUT $_;
  }
  close( IN ) || die "Cant close $filein: $!";
  close( OUT ) || die "Cant close $fileout: $!";
}

# append_chunk( file, chunk ) is a function
# to append a chunk to file.
sub append_chunk {
  my( $file, $chunk ) = @_;
  open( OUT, ">>" . $file ) || die "Cant open $file for appending: $!";
  print OUT "$chunk";
  close( OUT ) || die "Cant close $file: $!";
}