#!/usr/bin/perl
use strict;
use warnings;
use Config::General;
use Data::Dumper;
use Text::Xslate qw(mark_raw);
use File::Slurp;
use File::Copy;
open STDERR, '>', "/dev/null";

my $LCWM             = '/etc/nginx/lcwm2';
my $A2CFG            = '/etc/httpd/conf/httpd.conf' ;
my $NGCFG            = '/etc/nginx/nginx.conf' ;
my $NGCFGen          = "$NGCFG.gen" ;
my $NGCFGbak         = "$NGCFG." . time() ;
my $A2PORT           = 81 ;
my $A2PORTS          = 8443 ;
my $NGPORT           = 80 ;
my $NGPORTS          = 443 ;
my $NGCFGBASE        = "$LCWM/nginx.base" ;
my $NGCFGVHOSTSTAT   = "$LCWM/vhost_static.conf" ;
my $NGCFG_CUSTOM_DIR = "$LCWM/custom";
my $A2CLEAN          = "$LCWM/ap2_clean.conf" ;
my $DEFLISTEN        = " default sndbuf=98304 backlog=2048 deferred" ;

my $template_def_ips = qq{
# aka null.tld + $DEFLISTEN
server {
    : for \$ipv4 -> \$ip {
     listen <: \$ip :>:$NGPORT $DEFLISTEN;
    : }
    : for \$ipv6 -> \$ip {
     listen <: \$ip :>:$NGPORT $DEFLISTEN;
    : }
    access_log  off;
    error_log   /dev/null;
    server_name "";
    return      444;
}
};
my $template_ng_vhost = q{
#---vhost for domain <: $server_name :> on IP <: $listen :> <: $ssl :> ----
server {
    : for $ips.ipv4 -> $ip {
     listen <: $ip :>:<: $ngport :> <: $ssl :>;
    : }
    : for $ips.ipv6 -> $ip {
     listen <: $ip :>:<: $ngport :> <: $ssl :>;
    : }
    server_name   <: $server_name :> <: $alias :> ;
    root          <: $root :> ;
    access_log off; # /var/log/nginx/<: $server_name :>.access.log  main buffer=32k;
    error_log  /var/log/nginx/<: $server_name :>.error.log  warn;
    : if $include_slash == "" {
    location @apache {
        proxy_pass   http://<: $main_ip :>:<: $a2port :>;
        proxy_redirect http://<: $server_name :>:<: $a2port :> http://<: $server_name :>;
        proxy_redirect http://www.<: $server_name :>:<: $a2port :> http://www.<: $server_name :>;
        proxy_redirect http://webmail.<: $server_name :>:<: $a2port :> http://webmail.<: $server_name :>;
        proxy_redirect http://admin.<: $server_name :>:<: $a2port :> http://admin.<: $server_name :>;
    }
    location / {
        try_files maintenance.html @apache;
    }
    : } else {
    <: $include_slash :>
    : }
    <: $include_static :> 
    : if $ssl != "" {
    ssl_certificate           <: $ssl_certificate          :> ;
    ssl_certificate_key       <: $ssl_certificate_key      :> ;
    ssl_session_timeout 1d;
    ssl_session_cache shared:SSL:50m;
    ssl_session_tickets off;
    ssl_dhparam /etc/ssl/certs/dhparam.pem;
    ssl_protocols TLSv1.2;
    ssl_ciphers 'ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256';
    ssl_prefer_server_ciphers on;
    #ssl_stapling on;
    #ssl_stapling_verify on;
    resolver 8.8.8.8;
    : }
}
};


sub update_pem {
# Bash analog:
# cat $SSLSERT > $SSLSERT".pem"
# cat $SSLCA  >> $SSLSERT".pem"
#
    my ($SSLSERT, $SSLCA) = @_ ;
    my $OUT = $SSLSERT . ".pem";
    write_file( $OUT, {append => 0 }, read_file($SSLSERT) ) ;
    write_file( $OUT, {append => 1 }, read_file($SSLCA) ) if ( $SSLCA );
    return $OUT;
}

sub uniq {
# remove duplicates from array
#
    my %seen;
    return grep { !$seen{$_}++ } @_;
}

sub get_ips {
# get array of ips from VirtualHost string, like this "IP1:http IP2:http [ipv6_1]:http [ipv6_2]:http"
#
    my ($text) = @_ ;
    my %hash;
    my @ipv6 = uniq ( $text =~ m/\[.+?\]/sg    ) ;
    my @ipv6_wo_local = grep ! /\[fe80/, @ipv6 ;
       @ipv6_wo_local = grep ! /\[2001/, @ipv6_wo_local ;
    my @ipv4 = uniq ( $text =~ m/[0-9.]{7,}/sg ) ;
    $hash{ipv6} = \@ipv6_wo_local ;
    $hash{ipv4} = \@ipv4 ;
    return \%hash ;
    }

sub cook_ng_vhost {
# convert [httpd.conf->Config::General]=>@vh_array->{$vhost} to %ng_hash=>[Text::Xslate->nginx.conf]
#
    my ($vh, $ip_port) = @_ ;
    my $port = $vh->{SSLEngine} ? $NGPORTS : $NGPORT ;
    my %hash;
    my $server_name = $vh->{ServerName};
    my @statics = glob "/home/*/configs/$server_name.static /etc/nginx/*/custom/$server_name.static";
    my @slashes = glob "/home/*/configs/$server_name.slash  /etc/nginx/*/custom/$server_name.slash";
    my $include_static = "/fake_path";
    my $include_slash  = "/fake_path";
    $include_static = $statics[0] if $statics[0] ;
    $include_slash  = $slashes[0] if $slashes[0] ;
    #print $server_name . " " . $include_static  . " " . $include_slash . "\n";
    $hash{'alias'}                   = ref $vh->{ServerAlias} eq 'ARRAY' ? join(" ", @{$vh->{ServerAlias}}) : $vh->{ServerAlias} ;
    $hash{'root'}                    = $vh->{DocumentRoot} ;
    $hash{'server_name'}             = $vh->{ServerName} ;
    $hash{'main_ip'}                 = get_ips($ip_port)->{ipv4}[0] ;
    $hash{'a2port'}                  = $A2PORT ;
    $hash{'ips'}                     = get_ips($ip_port) ;
    $hash{'ngport'}                  = $vh->{SSLEngine} ? $NGPORTS : $NGPORT ;
    $hash{'ssl'}                     = $vh->{SSLEngine} ? "ssl" : "";
    $hash{'ssl_certificate'}         = $vh->{SSLEngine} ? update_pem( $vh->{SSLCertificateFile}, $vh->{SSLCACertificateFile} ) : "" ;
    $hash{'ssl_certificate_key'}     = $vh->{SSLCertificateKeyFile} ;
    $hash{'include_static'}          = (-f $include_static ) ? read_file( $include_static ) : "include $NGCFGVHOSTSTAT;" ; 
    $hash{'include_slash'}           = (-f $include_slash  ) ? read_file( $include_slash  ) : "" ;
    $hash{'include_static'}          = mark_raw( $hash{'include_static'} ) ;
    $hash{'include_slash'}           = mark_raw( $hash{'include_slash'}  ) ;
    return \%hash;
}

sub cook_ng_array {
    open(my $a2cfg,   '<:encoding(utf8)', $A2CFG  ) or die "unable to open $A2CFG: $!\n";
    open(my $a2clean, "+>",               $A2CLEAN) or die "$0: can't create temporary file: $!\n";
    while (<$a2cfg>) { print $a2clean "$_" if ( /^\<VirtualHost/ .. /\<\/VirtualHost\>/ ) } ;
    close   $a2cfg; 
    close   $a2clean;

    my %conf = Config::General->new($A2CLEAN)->getall();
    unlink  $A2CLEAN;
    my @ng_array = ();
    for my $ip_port (keys %{$conf{VirtualHost}}) { 
        if ( ref $conf{VirtualHost}{$ip_port} eq 'ARRAY' ) {
            for my $vh ( @{$conf{VirtualHost}{$ip_port}} ) {
                if (exists $vh->{ServerName} and exists $vh->{ServerAlias}) {
                    push  @ng_array, cook_ng_vhost($vh, $ip_port);
                }
            }
        } else { 
            my $vh = $conf{VirtualHost}{$ip_port} ;
            if (exists $vh->{ServerName} and exists $vh->{ServerAlias}) {
                push  @ng_array, cook_ng_vhost( $vh, $ip_port);
            }
        }
    }
    return \@ng_array;
}

sub render_ng {
    my $tx = Text::Xslate->new();
    write_file($NGCFGen, {append => 0 }, read_file( $NGCFGBASE ) );
    #print Dumper @ng_array;
    ## TO DO, rm durty code
    my $get_string_with_all_ips = `grep VirtualHost $A2CFG`;
    write_file( $NGCFGen, {append => 1 }, $tx->render_string( $template_def_ips, get_ips ( $get_string_with_all_ips ) ) );
    ## /TO DO
    foreach my $vhost (values cook_ng_array){
        write_file( $NGCFGen, {append => 1 }, $tx->render_string( $template_ng_vhost, $vhost ) );
    }
    write_file( $NGCFGen, {append => 1 }, "\n\#close section http {\n}" ) ;
    print "Config done ... " ;
}

sub reconf_ng {
    my @args = ("/usr/sbin/nginx", "-t", "-c", "$NGCFGen" );
    # Debug
    copy($NGCFGen, '/etc/nginx/test.conf');
    # -----
    if ( system(@args) == 0 ) {
        print "syntax is ok ... ";
    } else {
        print "syntax check failed ...\n";
        die "system @args failed: $?";
    }
    move($NGCFG, $NGCFGbak);
    copy($NGCFGen, $NGCFG);
    print "backup done ... ";
    #@args = ("/usr/sbin/nginx", "-s", "reload" );
    @args = ("service", "nginx", "restart" );
    if ( system(@args) == 0  or system(@args) == 256) {
        print "nginx reloaded. ALL OK\n";
    } else {
        print system(@args);
        copy($NGCFGbak, $NGCFG);
        print "nginx reload failed, revert config done ...\n";
        die "system @args failed: $?";
    }

}

render_ng ;
reconf_ng ;