#!/usr/bin/perl

use strict;
use Getopt::Long;
use Lemonldap::NG::Common::Conf;
use LWP::UserAgent;
use MIME::Base64;
use XML::LibXML;

#==============================================================================
# Get command line options
#==============================================================================
my %opts;
my $result = GetOptions(
    \%opts,              'metadata|m=s',
    'certificate|c=s',   'verbose|v',
    'help|h',            'spconfprefix|s=s',
    'idpconfprefix|i=s', 'warning|w',
    'remove|r'
);

#==============================================================================
# Help
#==============================================================================
if ( $opts{help} or !$opts{metadata} ) {
    print STDERR
"\nScript to import SAML metadata bundle file into LL::NG configuration\n\n";
    print STDERR "Usage: $0 -m <metadata file URL>\n\n";
    print STDERR "Options:\n";
    print STDERR
"\t-c (--certificate): URL of certificate, to check metadata document signature\n";
    print STDERR
      "\t-i (--idpconfprefix): Prefix used to set IDP configuration key\n";
    print STDERR "\t-h (--help): print this message\n";
    print STDERR "\t-m (--metadata): URL of metadata document\n";
    print STDERR
      "\t-s (--spconfprefix): Prefix used to set SP configuration key\n";
    print STDERR "\t-w (--warning): print debug messages\n";
    exit 1;
}

#==============================================================================
# Default values
#==============================================================================

my $spConfKeyPrefix  = $opts{spconfprefix}  || "sp-";
my $idpConfKeyPrefix = $opts{idpconfprefix} || "idp-";

# Set here attributes that are declared for your SP in the federation
# They will be set as exported attributes for all IDP
my $exportedAttributes = {
    'cn'                          => '0;cn',
    'eduPersonPrincipalName'      => '0;eduPersonAffiliation',
    'givenName'                   => '0;givenName',
    'surname'                     => '0;surname',
    'displayName'                 => '0;displayName',
    'eduPersonAffiliation'        => '0;eduPersonAffiliation',
    'eduPersonPrimaryAffiliation' => '0;eduPersonPrimaryAffiliation',
    'mail'                        => '0;mail',
    'supannListeRouge'            => '0;supannListeRouge',
    'supannEtuCursusAnnee'        => '0;supannEtuCursusAnnee',
};

# Set here options that are applied on all SP from the federation
my $spOptions = {
    'samlSPMetaDataOptionsCheckSLOMessageSignature'   => 1,
    'samlSPMetaDataOptionsCheckSSOMessageSignature'   => 1,
    'samlSPMetaDataOptionsEnableIDPInitiatedURL'      => 0,
    'samlSPMetaDataOptionsEncryptionMode'             => 'none',
    'samlSPMetaDataOptionsForceUTF8'                  => 1,
    'samlSPMetaDataOptionsNameIDFormat'               => '',
    'samlSPMetaDataOptionsNotOnOrAfterTimeout'        => 72000,
    'samlSPMetaDataOptionsOneTimeUse'                 => 0,
    'samlSPMetaDataOptionsSessionNotOnOrAfterTimeout' => 72000,
    'samlSPMetaDataOptionsSignSLOMessage'             => 1,
    'samlSPMetaDataOptionsSignSSOMessage'             => 1
};

# Set here options that are applied on all IDP from the federation
my $idpOptions = {
    'samlIDPMetaDataOptionsAdaptSessionUtime'        => 0,
    'samlIDPMetaDataOptionsAllowLoginFromIDP'        => 0,
    'samlIDPMetaDataOptionsAllowProxiedAuthn'        => 0,
    'samlIDPMetaDataOptionsCheckAudience'            => 1,
    'samlIDPMetaDataOptionsCheckSLOMessageSignature' => 1,
    'samlIDPMetaDataOptionsCheckSSOMessageSignature' => 1,
    'samlIDPMetaDataOptionsCheckTime'                => 1,
    'samlIDPMetaDataOptionsEncryptionMode'           => 'none',
    'samlIDPMetaDataOptionsForceAuthn'               => 0,
    'samlIDPMetaDataOptionsForceUTF8'                => 0,
    'samlIDPMetaDataOptionsIsPassive'                => 0,
    'samlIDPMetaDataOptionsNameIDFormat'             => 'transient',
    'samlIDPMetaDataOptionsRelayStateURL'            => 0,
    'samlIDPMetaDataOptionsSignSLOMessage'           => -1,
    'samlIDPMetaDataOptionsSignSSOMessage'           => -1,
    'samlIDPMetaDataOptionsStoreSAMLToken'           => 0
};

my $idpCounter = {
    'found'    => 0,
    'updated'  => 0,
    'created'  => 0,
    'rejected' => 0,
    'removed'  => 0
};
my $spCounter = {
    'found'    => 0,
    'updated'  => 0,
    'created'  => 0,
    'rejected' => 0,
    'removed'  => 0
};

#==============================================================================
# Main
#==============================================================================
my $conf     = Lemonldap::NG::Common::Conf->new();
my $lastConf = $conf->getConf();

if ( $opts{verbose} ) {
    print "Read configuration " . $lastConf->{cfgNum} . "\n";
}

# IDP and SP lists
my ( $idpList, $spList, $mdIdpList, $mdSpList );

# List current SAML partners
foreach my $spConfKey ( keys %{ $lastConf->{samlSPMetaDataXML} } ) {
    my ( $tmp, $entityID ) =
      ( $lastConf->{samlSPMetaDataXML}->{$spConfKey}->{samlSPMetaDataXML} =~
          /entityID=(['"])(.+?)\1/si );
    if ( $spConfKey =~ /^$spConfKeyPrefix/ ) {
        $spList->{$entityID} = $spConfKey;
        if ( $opts{verbose} ) {
            print "Existing SAML partner found: [SP] $entityID ($spConfKey)\n";
        }
    }
}

foreach my $idpConfKey ( keys %{ $lastConf->{samlIDPMetaDataXML} } ) {
    my ( $tmp, $entityID ) =
      ( $lastConf->{samlIDPMetaDataXML}->{$idpConfKey}->{samlIDPMetaDataXML} =~
          /entityID=(['"])(.+?)\1/si );
    if ( $idpConfKey =~ /^$idpConfKeyPrefix/ ) {
        $idpList->{$entityID} = $idpConfKey;
        if ( $opts{verbose} ) {
            print
              "Existing SAML partner found: [IDP] $entityID ($idpConfKey)\n";
        }
    }

    # Download metadata file
    my $ua = LWP::UserAgent->new;
    $ua->timeout(10);
    $ua->env_proxy;

    my $metadata_file = $opts{metadata};

    if ( $opts{verbose} ) {
        print "Try to download metadata file at $metadata_file\n";
    }
    my $response = $ua->get($metadata_file);

    if ( $response->is_success ) {
        if ( $opts{verbose} ) {
            print "Metadata file found\n";
        }
    }
    else {
        die $response->status_line;
    }

    my $dom = XML::LibXML->load_xml( string => $response->decoded_content );

    # Check file signature
    if ( $opts{certificate} ) {
        my $certificate_file = $opts{certificate};
        if ( $opts{verbose} ) {
            print "Try to download certificate file at $certificate_file\n";
        }
        my $cert_response = $ua->get($certificate_file);

        if ( $cert_response->is_success ) {
            if ( $opts{verbose} ) {
                print "Certificate file found:\n"
                  . $cert_response->decoded_content . "\n";
            }
        }
        else {
            die $cert_response->status_line;
        }

        if ( $opts{verbose} ) {
            print "Check metadata signature with certificate";
        }

        # TODO
        print STDERR "[WARN] Signature verification not yet implemented\n"
          if $opts{warning};
    }

    # Remove extensions
    foreach ( $dom->findnodes('//md:Extensions') ) { $_->unbindNode; }

    # Browse all partners
    foreach my $partner (
        $dom->findnodes('/md:EntitiesDescriptor/md:EntityDescriptor') )
    {
        my $entityID = $partner->getAttribute('entityID');

        # Add required XML namespaces
        $partner->setNamespace( "urn:oasis:names:tc:SAML:2.0:metadata",
            "md", 0 );
        $partner->setNamespace( "urn:oasis:names:tc:SAML:2.0:assertion",
            "saml", 0 );
        $partner->setNamespace( "http://www.w3.org/2000/09/xmldsig#", "ds", 0 );

        # Check IDP or SP
        if ( my $idp = $partner->findnodes('./md:IDPSSODescriptor') ) {
            $idpCounter->{found}++;
            $mdIdpList->{$entityID} = 1;

            # Check if SAML 2.0 is supported
            if (
                $partner->findnodes(
'./md:IDPSSODescriptor/md:SingleSignOnService[contains(@Binding,"urn:oasis:names:tc:SAML:2.0:")]'
                )
              )
            {

                # Read metadata
                my $partner_metadata = $partner->toString;
                $partner_metadata =~ s/\n//g;

                # Check if entityID already in configuration
                if ( defined $idpList->{$entityID} ) {

                    # Update metadata
                    $lastConf->{samlIDPMetaDataXML}->{ $idpList->{$entityID} }
                      ->{samlIDPMetaDataXML} = $partner_metadata;

                    # Update attributes
                    $lastConf->{samlIDPMetaDataExportedAttributes}
                      ->{ $idpList->{$entityID} } = $exportedAttributes;

                    # Update options
                    $lastConf->{samlIDPMetaDataOptions}
                      ->{ $idpList->{$entityID} } = $idpOptions;

                    if ( $opts{verbose} ) {
                        print "Update IDP $entityID in configuration\n";
                    }
                    $idpCounter->{updated}++;
                }
                else {
                    # Create a new partner
                    my $entityIDKey = $entityID;
                    $entityIDKey =~ s/^https?:\/\///;
                    $entityIDKey =~ s/[^a-zA-Z0-9]/-/g;
                    my $confKey = $idpConfKeyPrefix . $entityIDKey;

                    # Metadata
                    $lastConf->{samlIDPMetaDataXML}->{$confKey}
                      ->{samlIDPMetaDataXML} = $partner_metadata;

                    # Attributes
                    $lastConf->{samlIDPMetaDataExportedAttributes}->{$confKey}
                      = $exportedAttributes;

                    # Options
                    $lastConf->{samlIDPMetaDataOptions}->{$confKey} =
                      $idpOptions;

                    if ( $opts{verbose} ) {
                        print
"Declare new IDP $entityID (configuration key $confKey)\n";
                    }
                    $idpCounter->{created}++;
                }

            }
            else {
                print STDERR
"[WARN] IDP $entityID is not compatible with SAML 2.0, it will not be imported.\n"
                  if $opts{warning};
                $idpCounter->{rejected}++;
            }
        }
        if ( my $sp = $partner->findnodes('./md:SPSSODescriptor') ) {
            $spCounter->{found}++;
            $mdSpList->{$entityID} = 1;

            # Check if SAML 2.0 is supported
            if (
                $partner->findnodes(
'./md:SPSSODescriptor/md:AssertionConsumerService[contains(@Binding,"urn:oasis:names:tc:SAML:2.0:")]'
                )
              )
            {

                # Read requested attributes
                my $requestedAttributes = {};
                if (
                    $partner->findnodes(
'./md:SPSSODescriptor/md:AttributeConsumingService/md:RequestedAttribute'
                    )
                  )
                {
                    foreach my $requestedAttribute (
                        $partner->findnodes(
'./md:SPSSODescriptor/md:AttributeConsumingService/md:RequestedAttribute'
                        )
                      )
                    {
                        my $name = $requestedAttribute->getAttribute("Name");
                        my $friendlyname =
                          $requestedAttribute->getAttribute("FriendlyName");
                        my $nameformat =
                          $requestedAttribute->getAttribute("NameFormat");
                        $requestedAttributes->{$friendlyname} =
                          "1;$name;$nameformat;$friendlyname";
                        if ( $opts{verbose} ) {
                            print
"Attribute $friendlyname ($name) requested by SP $entityID\n";
                        }
                    }
                }
                else {
                    $requestedAttributes =
                      { 'cn' => '1;cn', 'uid' => '1;uid', 'mail' => '1;mail' };
                }

                # Remove AttributeConsumingService node
                foreach (
                    $partner->findnodes(
                        './md:SPSSODescriptor/md:AttributeConsumingService')
                  )
                {
                    $_->unbindNode;
                }

                # Read metadata
                my $partner_metadata = $partner->toString;
                $partner_metadata =~ s/\n//g;

                # Check if entityID already in configuration
                if ( defined $spList->{$entityID} ) {

                    # Update metadata
                    $lastConf->{samlSPMetaDataXML}->{ $spList->{$entityID} }
                      ->{samlSPMetaDataXML} = $partner_metadata;

                    # Update attributes
                    $lastConf->{samlSPMetaDataExportedAttributes}
                      ->{ $spList->{$entityID} } = $requestedAttributes;

                    # Update options
                    $lastConf->{samlSPMetaDataOptions}->{ $spList->{$entityID} }
                      = $spOptions;

                    if ( $opts{verbose} ) {
                        print "Update SP $entityID in configuration\n";
                    }
                    $spCounter->{updated}++;
                }
                else {
                    # Create a new partner
                    my $entityIDKey = $entityID;
                    $entityIDKey =~ s/^https?:\/\///;
                    $entityIDKey =~ s/[^a-zA-Z0-9]/-/g;
                    my $confKey = $spConfKeyPrefix . $entityIDKey;

                    # Metadata
                    $lastConf->{samlSPMetaDataXML}->{$confKey}
                      ->{samlSPMetaDataXML} = $partner_metadata;

                    # Attributes
                    $lastConf->{samlSPMetaDataExportedAttributes}->{$confKey} =
                      $requestedAttributes;

                    # Options
                    $lastConf->{samlSPMetaDataOptions}->{$confKey} = $spOptions;

                    if ( $opts{verbose} ) {
                        print
"Declare new SP $entityID (configuration key $confKey)\n";
                    }
                    $spCounter->{created}++;
                }

            }
            else {
                print STDERR
"[WARN] SP $entityID is not compatible with SAML 2.0, it will not be imported.\n"
                  if $opts{warning};
                $spCounter->{rejected}++;
            }

        }

    }

    # Remove partners
    if ( $opts{remove} ) {
        foreach ( keys %$idpList ) {
            my $idpConfKey = $idpList->{$_};
            unless ( defined $mdIdpList->{$_} ) {
                delete $lastConf->{samlIDPMetaDataXML}->{$idpConfKey};
                delete $lastConf->{samlIDPMetaDataExportedAttributes}
                  ->{$idpConfKey};
                delete $lastConf->{samlIDPMetaDataOptions}->{$idpConfKey};
                $idpCounter->{removed}++;
                if ( $opts{verbose} ) {
                    print "Remove IDP $idpConfKey\n";
                }
            }
        }

        foreach ( keys %$spList ) {
            my $spConfKey = $spList->{$_};
            unless ( defined $mdSpList->{$_} ) {
                delete $lastConf->{samlSPMetaDataXML}->{$spConfKey};
                delete $lastConf->{samlSPMetaDataExportedAttributes}
                  ->{$spConfKey};
                delete $lastConf->{samlSPMetaDataOptions}->{$spConfKey};
                $spCounter->{removed}++;
                if ( $opts{verbose} ) {
                    print "Remove SP $spConfKey\n";
                }
            }
        }
    }
}

# Register configuration
my $numConf = $conf->saveConf( $lastConf, ( cfgNumFixed => 1 ) );

unless ($numConf) {
    print "[ERROR] Unable to save configuration\n";
    exit 1;
}

print "[IDP]\tFound: "
  . $idpCounter->{found}
  . "\tUpdated: "
  . $idpCounter->{updated}
  . "\tCreated: "
  . $idpCounter->{created}
  . "\tRemoved: "
  . $idpCounter->{removed}
  . "\tRejected: "
  . $idpCounter->{rejected} . "\n";
print "[SP]\tFound: "
  . $spCounter->{found}
  . "\tUpdated: "
  . $spCounter->{updated}
  . "\tCreated: "
  . $spCounter->{created}
  . "\tRemoved: "
  . $spCounter->{removed}
  . "\tRejected: "
  . $spCounter->{rejected} . "\n";
print "[OK] Configuration $numConf saved\n";
exit 0;
