Foodloop-Server/lib/Pear/LocalLoop/Controller/Api/Sendmessage.pm

package Pear::LocalLoop::Controller::Api::Sendmessage;
use Mojo::Base 'Mojolicious::Controller';
use LWP::UserAgent;
use JSON;
use JSON::Parse 'parse_json';
use Mojo::JWT;
use Mojo::File;
use Carp;

has error_messages => sub {
    return {
        topic => {
            required => { message => 'Topic is required', status => 400 },
        },
        sender => {
            required => { message => 'Sender name is required', status => 400 },
            in_resultset =>
              { message => 'Sender org not found', status => 400 },
        },
        messagetext => {
            required => { message => 'Message is required', status => 400 },
        },
    };
};

# Credit: Peter Scott/StackOverflow https://stackoverflow.com/a/53357961/4580273
# Credit: jeffez/StackOverflow https://stackoverflow.com/q/56556438/4580273

my $jwt = create_jwt_from_path_and_scopes( './localspend-47012.json',
    'email https://www.googleapis.com/auth/cloud-platform' );

my $ua = LWP::UserAgent->new();

my $response = $ua->post(
    'https://www.googleapis.com/oauth2/v4/token',
    {
        'grant_type' => 'urn:ietf:params:oauth:grant-type:jwt-bearer',
        'assertion'  => $jwt
    }
);

my $bearer_token = parse_json( $response->content );

sub create_jwt_from_path_and_scopes {
    my ( $path, $scope ) = @_;
    croak("No path provided")    if not defined $path;
    croak("$path not available") if not -f $path;
    my $json = decode_json( Mojo::File->new($path)->slurp );
    croak("No Private key in $path") if not defined $json->{private_key};
    croak("Not a service account")   if $json->{type} ne 'service_account';
    my $jwt = Mojo::JWT->new();
    $jwt->algorithm('RS256');
    $jwt->secret( $json->{private_key} );

    $jwt->claims(
        {
            iss   => $json->{client_email},
            scope => $scope,
            aud   => 'https://www.googleapis.com/oauth2/v4/token',
            iat   => time(),
            exp   => time() + 3600
        }
    );
    $jwt->set_iat(1);
    return $jwt->encode;
}

sub post_message {
    my $c = shift;

    my $validation = $c->validation;
    $validation->input( $c->stash->{api_json} );

    $validation->required('topic');
    $validation->required('sender')
      ->in_resultset( 'name', $c->schema->resultset('Organisation') );
    $validation->required('messagetext');

    return $c->api_validation_error if $validation->has_error;

    my $end_point =
      "https://fcm.googleapis.com/v1/projects/localspend-47012/messages:send";

    my $request = HTTP::Request->new( 'POST', $end_point );
    $request->header(
        'Authorization' => "Bearer $bearer_token->{access_token}" );
    $request->header( 'Content-Type' => 'application/json' );

    $request->content(
        JSON::encode_json(
            {
                message => {
                    topic        => $validation->param('topic'),
                    notification => {
                        title => $validation->param('sender'),
                        body  => $validation->param('messagetext')
                    },
                    webpush => {
                        headers => {
                            urgency => 'very-low'
                        },
                        notification => {
                            title => $validation->param('sender'),
                            body  => $validation->param('messagetext'),
                        }
                    }
                }
            }
        )
    );

    my $response = $ua->request($request);

    if ( $response->is_success ) {
        return $c->render(
            json => {
                success => Mojo::JSON->true,
                message => 'Your message has been sent successfully!',
            }
        );
    }
    elsif ( $response->is_error ) {
        return $c->render(
            json => {
                success => Mojo::JSON->false,
                message => [ $response->decoded_content, $jwt, $bearer_token ],
                error   => 'message_error',
            },
            status => $response->code,
        );
    }
}

1;