#!/usr/bin/perl -w

use FindBin;
use lib "$FindBin::Bin/../../../perl_lib";


=head1 NAME


=head1 SYNOPSIS

=head1 DESCRIPTION


=cut

use EPrints;
use JSON;
use Data::Dumper;

use strict;
use warnings;

my $repositoryid = $ARGV[0];
#### Repo stuff ####
my $ep = EPrints->new();
my $repo = $ep->repository($repositoryid);
unless($repo) {die("could not find repository with id: $repositoryid");}

my $eprintid = $ARGV[1];
my @eprints;
if(defined $eprintid){
    print "Get unpaywall data for eprint/$eprintid...\n";
    my $eprints = [$eprintid];
    @eprints = @{$eprints};
}else{
    print "Get unpaywall data for all REF eligible records...\n";
    if($repo->can_call("hefce_oa", "get_eligible_eprints")){
        my $eprints = $repo->call(["hefce_oa", "get_eligible_eprints"],$repo);

        # in case we encounter any trouble querying unpaywall API, lets prioritise new updates based on when an item was last updated
        my %eprint_audits = ();
        my $eprint_ds = $repo->dataset( "eprint" );
        my $audit_ds = $repo->dataset( "hefce_oa_audit" );

        my $list = $eprint_ds->list( $eprints );

        $list->map(sub{
            (undef, undef, my $eprint) = @_;
            my $audit = $audit_ds->dataobj_class->get_audit_record( $repo, $eprint );
            if( !defined $audit )
            {
                $eprint_audits{$eprint->id} = 0;
            }
            else
            {
                my $value = $audit->get_value( "up_datestamp" );
                my $field = $audit_ds->field( "up_datestamp" );               
                $eprint_audits{$eprint->id} = $field->ordervalue_basic( $value );
            }
        });
        
        @eprints = sort { $eprint_audits{$a} cmp $eprint_audits{$b} } keys %eprint_audits;
    }
}

if($repo->can_call("hefce_oa", "get_unpaywall")){
    for my $eprintid(@eprints){
        if( !defined($eprintid) ){
            _fatal($repo,,"get_unpaywall called without id argument");
        }elsif( $eprintid !~ /^([0-9]+)$/ ){
            _fatal($repo, "get_unpaywall requires numeric eprintid argument");
        }

         my $eprint = $repo->dataset( "eprint" )->dataobj( $eprintid );
        _fatal($repo, "No eprint found with supplied parameters") if (!EPrints::Utils::is_set($eprint));

        my ($status, $response, $details) = $repo->call(["hefce_oa", "get_unpaywall"],$repo, $eprint);
    
        _fatal($repo, $response, $details) if($status eq "ERROR");
        
        if($status eq "SUCCESS")
        {
            _process($repo, $response, $eprint);
            sleep($repo->get_conf("hefce_oa","unpaywall_sleep")); # sleep to ensure we don't do over 100,000 calls in a day 
        }
    }

}else{
    _fatal($repo, "The REF CC audit check-up does not appear ot be properly installed");
}


sub _fatal {
    my ($repo, $msg, $response) = @_;

    my $json = JSON->new->allow_nonref;
 
    if(!defined $response){
        $repo->log($msg);
        print $json->encode( {error=> $msg} );
    }else{
        $repo->log($msg." ".$response->content);
        print $json->encode( {error=> $msg, status_line=> $response->status_line, code => $response->code, response => $json->utf8->decode($response->content)} );
    }
    #exit; 
}

sub _process {
    my ($repo, $response,$eprint) = @_;

    my $json = JSON->new->allow_nonref;

	if( ! $response->is_success ){
        _fatal($repo, "Error from unpaywall", $response);
    }else{
        my $up_data =  $json->utf8->decode( $response->content );
        my $ep_oai_id = EPrints::OpenArchives::to_oai_identifier( EPrints::OpenArchives::archive_id( $repo ), $eprint->get_id );

        # We have some data, but before we can use it we need an audit record
        my $audit_ds = $repo->dataset( "hefce_oa_audit" );
        my $audit = $audit_ds->dataobj_class->get_audit_record( $repo, $eprint );
        if( !defined $audit )
        {
            # we need to create a new audit record
            $audit = $audit_ds->create_dataobj(
                {
                    eprintid => $eprint->id
                }
            );
        }

        my $repo_host = $repo->get_conf("host");

        print "is_oa: ".$up_data->{is_oa}."\n";
        $audit->set_value( "up_is_oa", uc( $up_data->{is_oa} ) );

        my $up_loc = $up_data->{best_oa_location};
        if( defined $up_loc )
        { 
            $audit->set_value( "up_url_for_pdf", $up_loc->{url_for_pdf} );
        }

        my @up_locations;
        for my $up_loc (@{$up_data->{oa_locations}}){

            my $up_location = {};

            $up_location->{url} = $up_loc->{url};
            # If we do not have a value for url_for_pdf from the best_location we will get one from the first location that does have one.
            $audit->set_value( "up_url_for_pdf", $up_loc->{url_for_pdf} ) if(!EPrints::Utils::is_set($audit->value("up_url_for_pdf")) && EPrints::Utils::is_set($up_loc->{url_for_pdf}));
            $up_location->{pmh_id} = $up_loc->{pmh_id};
            $up_location->{is_best} = uc( $up_loc->{is_best} );
            
            push @up_locations, $up_location;

            if($up_loc->{is_best} eq "true"){
                print "\n### Unpaywall thinks that this is the best location ###\n\n";
                print "Repository institution => ".$up_loc->{repository_institution}."\n" if(defined $up_loc->{repository_institution});
                print "host_type => ".$up_loc->{host_type}."\n";
                print "pmh_id => ".$up_loc->{pmh_id}."\n" if(defined $up_loc->{pmh_id});
                print "url => ".$up_loc->{url}."\n";
                print "url_for_pdf => ".$up_loc->{url_for_pdf}."\n";
                print "version => ".$up_loc->{version}."\n";
                print "updated (by UP)=> ".$up_loc->{updated}."\n";

            }
            if(defined $up_loc->{pmh_id} && $up_loc->{pmh_id} =~ /$repo_host/){
                print "\n### Unpaywall oa_location looks like a match for this reposiotry ###\n\n";
                print "Repository institution => ".$up_loc->{repository_institution}."\n";
                print "host_type => ".$up_loc->{host_type}."\n";
                print "pmh_id => ".$up_loc->{pmh_id}."\n";
                print "url => ".$up_loc->{url}."\n";
                print "url_for_pdf => ".$up_loc->{url_for_pdf}."\n";
                print "version => ".$up_loc->{version}."\n";
                print "updated (by UP)=> ".$up_loc->{updated}."\n";

            }
        }

        $audit->set_value( "up_locations", \@up_locations );

        # now we have updated the core audit record, set the timestamp
        $audit->set_value( "up_datestamp", EPrints::Time::get_iso_timestamp() );
        $audit->commit;
    }
}