config.pm: replace Config::General

Config::General does not support Apache like definition and use of
variables. A minimal implementation of Apache-like configuration
allows to define variables by
  Define <variable-name> <variable-value>
and use them later by
  ${variable-name}
.

lib/calcms/config.pm

@@ -5,30 +5,16 @@ use warnings;
 no warnings 'redefine';
 
 use FindBin();
-use Config::General();
 
 #use base 'Exporter';
 our @EXPORT_OK = qw(get set);
 
 my $config = undef;
 
-sub set($) {
-    my $value = shift;
-    $config = $value;
-    return;
-}
 
 sub get($) {
     my $filename = shift;
-
-    return $config if ( defined $config ) && ( $config->{cache}->{cache_config} == 1 );
-
-    my $configuration = Config::General->new(
-        -ConfigFile => $filename,
-        -UTF8       => 1
-    );
-    config::set( $configuration->{DefaultConfig}->{config} );
-    return $config;
+    return read_config($filename);
 }
 
 sub getFromScriptLocation() {
@@ -37,5 +23,56 @@ sub getFromScriptLocation() {
     return config::get($configFile);
 }
 
+sub read_config {
+    my $file = $_[0];
+
+    my $vars  = {};
+    my @stack = ();
+    my $entry = {};
+
+    open my $fh, '<', $file or die;
+    while ( my $line = <$fh> ) {
+        chomp $line;
+
+        # comments
+        $line =~ s/\#.*//;
+
+        # trim
+        $line =~ s/(^\s+)|(\s+)$//;
+        next unless length $line;
+        if ( $line =~ /^<\/([^>]+)>$/ ) {
+
+            # close tag
+            my $name   = $1;
+            my $sentry = pop @stack;
+            die unless $sentry->{name} eq $name;
+            $entry = $sentry->{value};
+        } elsif ( $line =~ /^<([^>]+)>$/ ) {
+
+            # open tag
+            my $name = $1;
+            $entry->{$name} = {};
+            push @stack, { name => $name, value => $entry };
+            $entry = $entry->{$name};
+        } elsif ( $line =~ /^Define\s/ ) {
+            # define vars
+            my ( $attr, $key, $value ) = split /\s+/, $line, 3;
+            for my $var ( keys %$vars ) {
+                $value =~ s/\$\{$var\}/$vars->{$var}/;
+            }
+            $vars->{$key} = $value;
+        } else {
+            # attributes
+            my ( $key, $value ) = split /\s+/, $line, 2;
+            for my $var ( keys %$vars ) {
+                $value =~ s/\$\{$var\}/$vars->{$var}/;
+            }
+            $entry->{$key} = $value;
+        }
+    }
+    close $fh or die;
+    return $entry->{config};
+}
+
 #do not delete last line
 1;