blogbibtex

#!/bin/perl -W
# Convert BibTeX to Markdown. Produce the following:
#    1. List of URL targets
#    2. Sorted list of literature entries
#
# Elmar Klausmeier, 30-Sep-2023
# Elmar Klausmeier, 02-Dec-2023: adapting for Roman's bachelor thesis

use strict;
my ($i,$inArticle,$entry,$entryOrig,$type,$debug) = (0,0,"","",0);
my %H;	# hash of hash (each element in hash is a yet another hash)
my %Journals = (	# see http://cdsads.u-strasbg.fr/abs_doc/aas_macros.html
	'\aap'   => 'Astronomy & Astrophysics',
	'\aj'    => 'Astronomical Journal',
	'\apj'   => 'The Astrophysical Journal',
	'\apjl'  => 'Astrophysical Journal, Letters',
	'\apjs'  => 'Astrophysical Journal, Supplement',
	'\mnras' => 'Monthly Notices of the RAS',
	'\nat'   => 'Nature'
);

while (<>) {
	chomp;
	s/\s+$//;	# rtrim
	if (/^@(article|book|inproceedings|misc|phdthesis|software)\{([\-\w]+),$/) {
		($type,$entry,$entryOrig,$inArticle) = ($1,uc $2,$2,1);
		$H{$entry}{'entry'} = $entryOrig;
		$H{$entry}{'type'} = $type;
		printf("\t\tentry=|%s|, type=|%s|\n",$entry,$type) if ($debug);
	} elsif ($inArticle) {
		if (/^}\s*$/) { $inArticle = 0; next; }
		if (/^\s*(\w+)\s*=\s*(.+)(|,)$/) {
			my ($key,$value) = ($1,$2);
			$value =~ s/^"//;	# drop leading and trailing quotes
			$value =~ s/,$//;
			$value =~ s/"$//;

			# LaTeX foreign language character handling
			$value =~ s/\\ss\{\}/ß/g;
			$value =~ s/\{\\ss\}/ß/g;
			$value =~ s/\{\\"A\}/Ä/g;
			$value =~ s/\{\\"U\}/Ü/g;
			$value =~ s/\{\\"O\}/Ö/g;
			$value =~ s/\{\\"a\}/ä/g;
			$value =~ s/\{\\"u\}/ü/g;
			$value =~ s/\{\\"i\}/ï/g;
			$value =~ s/\{\\H\{o\}\}/ő/g;
			$value =~ s/\{\\"\\i\}/ï/g;
			$value =~ s/\{\\"o\}/ö/g;
			$value =~ s/\\"\{o\}/ö/g;
			$value =~ s/\{\\'A\}/Á/g;	# accent aigu
			$value =~ s/\{\\'E\}/É/g;	# accent aigu
			$value =~ s/\{\\'O\}/Ó/g;	# accent aigu
			$value =~ s/\{\\'U\}/Ú/g;	# accent aigu
			$value =~ s/\{\\'a\}/á/g;	# accent aigu
			$value =~ s/\{\\'e\}/é/g;	# accent aigu
			$value =~ s/\{\\'o\}/ó/g;	# accent aigu
			$value =~ s/\{\\'u\}/ú/g;	# accent aigu
			$value =~ s/\{\\`a\}/à/g;	# accent grave
			$value =~ s/\{\\`e\}/è/g;	# accent grave
			$value =~ s/\{\\`u\}/ù/g;	# accent grave
			$value =~ s/\{\\^a\}/â/g;	# accent circonflexe
			$value =~ s/\{\\^e\}/ê/g;	# accent circonflexe
			$value =~ s/\{\\^i\}/î/g;	# accent circonflexe
			$value =~ s/\{\\^\\i\}/î/g;	# accent circonflexe
			$value =~ s/\{\\^o\}/ô/g;	# accent circonflexe
			$value =~ s/\{\\^u\}/û/g;	# accent circonflexe
			$value =~ s/\{\\~A\}/Ã/g;	# minuscule a
			$value =~ s/\{\\~a\}/ã/g;	# minuscule a
			$value =~ s/\{\\~O\}/Õ/g;	# minuscule o
			$value =~ s/\{\\~o\}/õ/g;	# minuscule o
			$value =~ s/\{\\~n\}/ñ/g;	# palatal n
			$value =~ s/\{\\v\{C\}/Č/g;	# grapheme C
			$value =~ s/\{\\v\{c\}/č/g;	# grapheme c
			$value =~ s/\{\\v\{S\}/Š/g;	# grapheme S
			$value =~ s/\{\\v\{s\}/š/g;	# grapheme s
			$value =~ s/\{\\v\{Z\}/Ž/g;	# grapheme Z
			$value =~ s/\{\\v\{z\}/ž/g;	# grapheme z
	
			$value =~ s/\{|\}|\~//g;	# drop {}~
			$value =~ s/,$//;	# drop last comma
			$H{$entry}{$key} = $value;
			printf("\t\t\tentry=|%s|, key=|%s|, value=|%s|\n", $entry, $key, $value) if ($debug);
		}
	}
}

print("\n");
for my $e (sort keys %H) {
	my $He = \%H{$e};
	my $url = 
	printf("[%s]: %s\n", $H{$e}{'entry'},
		exists($H{$e}{'doi'}) ? 'https://doi.org/'.$H{$e}{'doi'}
		: defined($H{$e}{'url'}) ? $H{$e}{'url'}
		: defined($H{$e}{'eprint'}) ? 'https://arxiv.org/abs/'.$H{$e}{'eprint'}
		: '#Literature');
}
print("\n");

for my $e (sort keys %H) {
	my ($He,$date,$journal) = (\$H{$e},"","");
	if (exists($$He->{'year'}) && exists($$He->{'month'}) && exists($$He->{'day'})) {
		$date = sprintf("%02d-%s-%d", $$He->{'year'}, $$He->{'month'}, $$He->{'day'});
	} elsif (exists($$He->{'year'}) && exists($$He->{'month'})) {
		my $m = $$He->{'month'};
		$date = "\u$m" . "-" . 	$$He->{'year'};
	} elsif (exists($$He->{'year'})) {
		$date = $$He->{'year'};
	}
	if (exists($$He->{'journal'})) {
		my $t = $$He->{'journal'};
		$journal = ", " . ((substr($t,0,1) eq '\\') ? $Journals{$t} : $t);
		$journal .= ", Vol. " . $$He->{'volume'} if (exists($$He->{'volume'}));
		$journal .= ", Nr. " . $$He->{'number'} if (exists($$He->{'number'}));
		$journal .= ", pp. " . $$He->{'pages'} if (exists($$He->{'pages'}));
	}

	printf("%d. \\[%s\\] %s: _%s_, %s%s%s%s%s%s%s%s%s%s\n", ++$i, $H{$e}{'entry'}, $H{$e}{'author'},
		defined($H{$e}{'title'}) ? $H{$e}{'title'} : $H{$e}{'howpublished'},
		$date, $journal,
		defined($H{$e}{'booktitle'}) ? ', ' . $H{$e}{'booktitle'} : '',
		defined($H{$e}{'publisher'}) ? ', ' . $H{$e}{'publisher'} : '',
		defined($H{$e}{'school'}) ? ', ' . $H{$e}{'school'} : '',
		defined($H{$e}{'address'}) ? ', ' . $H{$e}{'address'} : '',
		defined($H{$e}{'series'}) ? ', ' . $H{$e}{'series'} : '',
		defined($H{$e}{'location'}) ? ', ' . $H{$e}{'location'} : '',
		exists($H{$e}{'doi'}) ? ', https://doi.org/'.$H{$e}{'doi'}
		: defined($H{$e}{'url'}) ? ', ' . $H{$e}{'url'} : '',
		exists($H{$e}{'eprint'}) ? ', https://arxiv.org/abs/'.$H{$e}{'eprint'} : ''
	);
}