class SRFBibTeX extends SMWResultPrinter {
    protected $m_title = '';
    protected $m_description = '';

    public function getMimeType( $res ) {
        return 'text/bibtex';
    }

    public function getFileName( $res ) {
        if ( $this->getSearchLabel( SMW_OUTPUT_WIKI ) != '' ) {
            return str_replace( ' ', '_', $this->getSearchLabel( SMW_OUTPUT_WIKI ) ) . '.bib';
        } else {
            return 'BibTeX.bib';
        }
    }

    public function getQueryMode( $context ) {
        return ( $context == SMWQueryProcessor::SPECIAL_PAGE ) ? SMWQuery::MODE_INSTANCES:SMWQuery::MODE_NONE;
    }

    public function getName() {
        return wfMsg( 'srf_printername_bibtex' );
    }

    protected function getResultText( SMWQueryResult $res, $outputmode ) {
        global $wgSitename;
        $result = '';
        $items = array();
        if ( $outputmode == SMW_OUTPUT_FILE ) { // make file
            if ( $this->m_title == '' ) {
                $this->m_title = $wgSitename;
            }
            $row = $res->getNext();
            while ( $row !== false ) {
                $type = '';
                $address = '';
                $annote = '';
                $author = '';
                $booktitle = '';
                $chapter = '';
                $crossref = '';
                $doi = '';
                $edition = '';
                $editor = '';
                $eprint = '';
                $howpublished = '';
                $institution = '';
                $journal = '';
                $key = '';
                $month = '';
                $note = '';
                $number = '';
                $organization = '';
                $pages = '';
                $publisher = '';
                $school = '';
                $series = '';
                $title = '';
                $type = '';
                $url = '';
                $volume = '';
                $year = '';

                foreach ( $row as $field ) {
                    $req = $field->getPrintRequest();

                    if ( ( strtolower( $req->getLabel() ) == "type" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $type = $value->getShortWikiText();
                        }
                    }


                    if ( ( strtolower( $req->getLabel() ) == "address" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $address = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "annote" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $annote = $value->getShortWikiText();
                        }
                    }
                    /* for flexibility, we permit 'author' or 'authors' */
                    if ( ( strtolower( $req->getLabel() ) == "author" ) || ( strtolower( $req->getLabel() ) == "authors" )  ) {
                        foreach ( $field->getContent() as $value ) {
                            $author .= ( $author ? ' and ':'' ) . $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "booktitle" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $booktitle = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "chapter" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $chapter = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "crossref" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $crossref = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "doi" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $doi = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "edition" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $edition = $value->getShortWikiText();
                        }
                    }
                    /* for flexibility, we permit 'editor' or 'editors' */
                    if ( ( strtolower( $req->getLabel() ) == "editor" ) || ( strtolower( $req->getLabel() ) == "editors" ) ) {
                        foreach ( $field->getContent() as $value ) {
                            $editor .= ( $editor ? ' and ':'' ) . $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "eprint" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $eprint = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "howpublished" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $howpublished = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "institution" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $institution = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "journal" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $journal = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "key" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $key = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "note" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $note = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "number" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $number = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "organization" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $organization = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "pages" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $pages = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "publisher" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $publisher = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "school" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $school = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "series" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $series = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "title" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $title = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "url" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $url = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "volume" ) || ( strtolower( $req->getLabel() ) == "journal_volume" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $volume = $value->getShortWikiText();
                        }
                    }



                    /*if we input a full date for the "month" and "year" BibTeX attributes, extract the month and year*/
                    if ( ( strtolower( $req->getLabel() ) == "date" ) ) {
                        $value = current( $field->getContent() );
                        if ( get_class( $value ) == 'SMWTimeValue' ) {
                            if ( $value !== false ) {
                            $year = $value->getYear();
                            $month = $value->getMonth();
                            }
                        }
                    }

                    if ( ( strtolower( $req->getLabel() ) == "year" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $year = $value->getShortWikiText();
                        }
                    }
                    if ( ( strtolower( $req->getLabel() ) == "month" ) ) {
                        $value = current( $field->getContent() );
                        if ( $value !== false ) {
                        $month = $value->getShortWikiText();
                        }
                    }


                }
                $items[] = new SMWBibTeXEntry( $type, $address, $annote, $author, $booktitle, $chapter, $crossref, $doi, $edition, $editor, $eprint, $howpublished, $institution, $journal, $key, $month, $note, $number, $organization, $pages, $publisher, $school, $series, $title, $url, $volume, $year );
                $row = $res->getNext();
            }
            foreach ( $items as $item ) {
                $result .= $item->text();
            }
        } else { // just make link to export
            if ( $this->getSearchLabel( $outputmode ) ) {
                $label = $this->getSearchLabel( $outputmode );
            } else {
                $label = wfMsgForContent( 'srf_bibtex_link' );
            }
            $link = $res->getQueryLink( $label );
            $link->setParameter( 'bibtex', 'format' );
            if ( $this->getSearchLabel( SMW_OUTPUT_WIKI ) != '' ) {
                $link->setParameter( $this->getSearchLabel( SMW_OUTPUT_WIKI ), 'searchlabel' );
            }
            $result .= $link->getText( $outputmode, $this->mLinker );
            $this->isHTML = ( $outputmode == SMW_OUTPUT_HTML ); // yes, our code can be viewed as HTML if requested, no more parsing needed
        }
        return $result;
    }

    public function getParameters() {
        if ( defined( 'SMW_SUPPORTS_VALIDATOR' ) ) {
            return array_merge( parent::getParameters(), $this->exportFormatParameters() );
        }
        else {
            return parent::exportFormatParameters();
        }
    }

}

/**
 * Represents a single entry in an BibTeX
 * @ingroup SMWQuery
 */
class SMWBibTeXEntry {
    private $bibTeXtype;
    private $URI;
    private $fields = array();

    public function SMWBibTeXEntry( $type, $address, $annote, $author, $booktitle, $chapter, $crossref, $doi, $edition, $editor, $eprint, $howpublished, $institution, $journal, $key, $month, $note, $number, $organization, $pages, $publisher, $school, $series, $title, $url, $volume, $year ) {
        if ( $type ) $this->bibTeXtype = ucfirst( $type ); else $this->bibTeXtype = 'Book';

        $fields = array();

        if ( $address ) $fields['address'] = $address;
        if ( $annote ) $fields['annote'] = $annote;
        if ( $author ) $fields['author'] = $author;
        if ( $booktitle ) $fields['booktitle'] = $booktitle;
        if ( $chapter ) $fields['chapter'] = $chapter;
        if ( $crossref ) $fields['crossref'] = $crossref;
        if ( $doi ) $fields['doi'] = $doi;
        if ( $edition ) $fields['edition'] = $edition;
        if ( $editor ) $fields['editor'] = $editor;
        if ( $eprint ) $fields['eprint'] = $eprint;
        if ( $howpublished ) $fields['howpublished'] = $howpublished;
        if ( $institution ) $fields['institution'] = $institution;
        if ( $journal ) $fields['journal'] = $journal;
        if ( $key ) $fields['key'] = $key;
        if ( $month ) $fields['month'] = $month;
        if ( $note ) $fields['note'] = $note;
        if ( $number ) $fields['number'] = $number;
        if ( $organization ) $fields['organization'] = $organization;
        if ( $pages ) $fields['pages'] = $pages;
        if ( $publisher ) $fields['publisher'] = $publisher;
        if ( $school ) $fields['school'] = $school;
        if ( $series ) $fields['series'] = $series;
        if ( $title ) $fields['title'] = $title;
        if ( $url ) $fields['url'] = $url;
        if ( $volume ) $fields['volume'] = $volume;
        if ( $year ) $fields['year'] = $year;

        $this->fields = $fields;

        // generating the URI: author last name + year + first letters of title
        $URI = '';
        if ( $author ) {
            $arrayAuthor = explode( ' ', $author );
            if ( array_key_exists( 1, $arrayAuthor ) ) $URI .= $arrayAuthor[1];
        }
        if ( $year ) $URI .= $year;
        if ( $title ) {
            $arrayTitle = explode( ' ', $title );
            foreach ( $arrayTitle as $titleWord ) {
                        $charsTitleWord = preg_split( '//', $titleWord, - 1, PREG_SPLIT_NO_EMPTY );
                        $URI .= $charsTitleWord[0];
                    }
        }
        $this->URI = strtolower( $URI );
    }


    /**
     * Creates the BibTeX output for a single item.
     */
    public function text() {
        $text  = '@' . $this->bibTeXtype . '{' . $this->URI . ",\r\n";
        foreach ( $this->fields as $key => $value ) {
            $text .= '  ' . $key . ' = "' . $value . '", ' . "\r\n";
        }
        $text .= "}\r\n\r\n";

        return $text;
    }

}