package session::AUTH::FaceBook;

use strict;
use warnings;
use LWP::UserAgent;
use JSON::XS;
use Data::Dumper;
use URI;
use URI::QueryParam;
use Encode;
use Contenido::Globals;

use vars qw($VERSION);
$VERSION = '4.1';

=for rem
    facebook:
	auto_create_user: 1
	app_id: 15 decimal digits
	app_secret: 32 hex digits
	authorize_url: https://www.facebook.com/dialog/oauth
	access_token_url: https://graph.facebook.com/oauth/access_token
	user_info_url: https://graph.facebook.com/me
	user_post_url: ~
	state: is passed back to your app as a parameter of the redirect_uri when the user completed the authentication
	store:
		class: "+Comments::Authentication::Store"
		type: facebook

=cut

our $JSON = JSON::XS->new->utf8;

=for rem SCHEMA

$m->redirect ( $fb_connect->authorize_url( facebook_redirect_uri => ... )->as_string );


=cut


sub new {
	my ($class, %config) = @_;
	my $self = bless {}, $class;

	$self->{facebook_authorize_url}		= 'https://www.facebook.com/dialog/oauth';
	$self->{facebook_access_token_url}	= 'https://graph.facebook.com/oauth/access_token';
	$self->{facebook_user_info_url}		= 'https://graph.facebook.com/me';

	for (qw(facebook_app_id facebook_app_secret)) {
		$self->{$_} = $config{$_} || $state->{session}{$_} || return undef;
	}
	$self->{timeout} = $state->{session}{connection_timeout} || 3;
	for (qw(facebook_user_post_url facebook_redirect_uri facebook_scope)) {
		$self->{$_} = $config{$_} || $state->{session}{$_};
	}
	return $self;
}

sub authorize_url {
	my $self = shift;
	my (%args) = @_;
	my $go = URI->new( $self->{facebook_authorize_url} );
	$go->query_param( client_id => $self->{facebook_app_id} );
	$go->query_param( state => $args{state} )		if $args{state};
	$go->query_param( scope => $self->{facebook_scope} )    if $self->{facebook_scope};
	$args{redirect_uri} ||= $self->{facebook_redirect_uri};
	for ( keys %args ) {
		$go->query_param( $_ => $args{$_} );
	}
	warn Dumper($go)					if $DEBUG;
	return $go;
}

sub authenticate {
	my ( $self, %authinfo ) = @_;
	warn "FB.authenticate"					if $DEBUG;
	# TODO: we need callback url
	my $local_session = $session || $keeper->{session}->get_session;
	my $redirect_uri = $self->{facebook_redirect_uri};
	
	my $access_token = $local_session->{facebook_access_token};
	my $expires = $local_session->{facebook_expires};
	if ($access_token and $expires > time) {
		warn "Already have access_token"		if $DEBUG;
	} else {
		undef $access_token;
	}
	my $code = $authinfo{'code'};
	unless ( $code ) {
		warn "Call to authenticate without code";
		return undef;
	}
	my $ua = LWP::UserAgent->new;
	$ua->timeout($self->{timeout});
	unless ($access_token) {
		my $req = URI->new( $self->{facebook_access_token_url});
		$req->query_param( client_id	=> $self->{facebook_app_id} );
		$req->query_param( redirect_uri	=> $redirect_uri );
		$req->query_param( client_secret=> $self->{facebook_app_secret} );
		$req->query_param( code		=> $code);
		warn "Get $req"					if $DEBUG;
		my $res = $ua->get($req);
		unless ($res->code == 200) {
			warn "access_token request failed: ".$res->status_line;
			return undef;
		}
		my %res = eval { URI->new("?".$res->content)->query_form };
		warn Dumper(\%res)				if $DEBUG;
		unless ($access_token = $res{access_token}) {
			warn "No access token in response: ".$res->content;
			return undef;
		}
		$local_session->set( facebook_access_token => $access_token );
		if( my $expires = $res{expires} ) {
                        $local_session->set( facebook_expires => time + $expires );
		} else {
			#$local_session->set( facebook_expires => time + 3600*24 );
		}
		warn "FB: requested access token"		if $DEBUG;
	} else {
		warn "FB: have access token"			if $DEBUG;
	}
	
	my $req = URI->new( $self->{facebook_user_info_url} );
	$req->query_param( access_token => $access_token );
	
	warn "Fetching user $req"				if $DEBUG;
	my $res = $ua->get($req);
	unless ($res->code == 200) {
		warn "user request failed: ".$res->status_line;
		return undef;
	}
	my $info;
	unless ( $info = eval { JSON::XS->new->utf8->decode($res->content) } ) {
		warn "user '".$res->content."' decode failed: $@";
		return undef;
	}
	warn "Userhash = ".Dumper($info)			if $DEBUG;
	#warn "facebook: user=$info->{name} / $info->{id} / $info->{gender}";

        $local_session->delete( 'facebook_redirect_url' );

	my @plugins = split (/[\ |\t]+/, $state->{plugins});
	my $name = Encode::encode('utf-8', $info->{name});
	Encode::from_to( $name, 'utf-8', 'koi8-r' );
	if ( grep { $_ eq 'users' } @plugins ) {
		my $user = $keeper->{users}->get_profile( login => 'facebook:'.$info->{id} );
		unless ( ref $user ) {
			my $user_class = $state->{users}->profile_document_class;
			$user = $user_class->new( $keeper );
			$user->login( 'facebook:'.$info->{id} );
			$user->name( $name );
			$user->status( 1 );
			$user->type( 0 );
			$user->login_method('facebook');
			$user->country( $info->{locale} );
			$user->email( undef );

			my ($prop_ava) = grep { $_->{attr} eq 'avatar' && $_->{type} eq 'image' } $user->structure;
			if ( ref $prop_ava ) {
				my $avatar = $user->_store_image( 'https://graph.facebook.com/'.$info->{username}.'/picture?type=large', attr => 'avatar' );
				local $Data::Dumper::Indent = 0;
				$user->avatar( Data::Dumper::Dumper($avatar) );
			}

			$user->store;
		} else {
			my ($prop_ava) = grep { $_->{attr} eq 'avatar' && $_->{type} eq 'image' } $user->structure;
			if ( ref $prop_ava ) {
				my $avatar = $user->get_image( 'avatar' );
				unless ( ref $avatar && exists $avatar->{filename} ) {
					my $avatar = $user->_store_image( 'https://graph.facebook.com/'.$info->{username}.'/picture?type=large', attr => 'avatar' );
					local $Data::Dumper::Indent = 0;
					$user->avatar( Data::Dumper::Dumper($avatar) );
					$user->store;
				}
			}
		}
		my %data = (
			id	=> $user->id,
			name	=> $user->name,
			login	=> $user->login,
			status	=> $user->status,
			type	=> $user->type,
			ltime   => time,
			avatar	=> 'https://graph.facebook.com/'.$info->{username}.'/picture',
		);
		$local_session->set( %data );
        } else {
		my %data = (
			id	=> $info->{id},
			name	=> $name,
			login	=> 'facebook:'.$info->{id},
			status	=> 1,
			type	=> 0,
			auth_by	=> 'facebook',
			ltime	=> time,
			avatar	=> 'https://graph.facebook.com/'.$info->{username}.'/picture?type=large',
		);
		$local_session->set ( %data );
	}
	return $local_session;
}

1;