/* Title: Pure/Tools/bibtex.scala
Author: Makarius
BibTeX support.
*/
package isabelle
import scala.collection.mutable
import scala.util.parsing.input.{Reader, CharSequenceReader}
import scala.util.parsing.combinator.RegexParsers
object Bibtex
{
/** content **/
private val months = List(
"jan",
"feb",
"mar",
"apr",
"may",
"jun",
"jul",
"aug",
"sep",
"oct",
"nov",
"dec")
def is_month(s: String): Boolean = months.contains(s.toLowerCase)
private val commands = List("preamble", "string")
def is_command(s: String): Boolean = commands.contains(s.toLowerCase)
sealed case class Entry(
kind: String,
required: List[String],
optional_crossref: List[String],
optional_other: List[String])
{
def is_required(s: String): Boolean = required.contains(s.toLowerCase)
def is_optional(s: String): Boolean =
optional_crossref.contains(s.toLowerCase) || optional_other.contains(s.toLowerCase)
def fields: List[String] = required ::: optional_crossref ::: optional_other
def template: String =
"@" + kind + "{,\n" + fields.map(x => " " + x + " = {},\n").mkString + "}\n"
}
val entries: List[Entry] =
List(
Entry("Article",
List("author", "title"),
List("journal", "year"),
List("volume", "number", "pages", "month", "note")),
Entry("InProceedings",
List("author", "title"),
List("booktitle", "year"),
List("editor", "volume", "number", "series", "pages", "month", "address",
"organization", "publisher", "note")),
Entry("InCollection",
List("author", "title", "booktitle"),
List("publisher", "year"),
List("editor", "volume", "number", "series", "type", "chapter", "pages",
"edition", "month", "address", "note")),
Entry("InBook",
List("author", "editor", "title", "chapter"),
List("publisher", "year"),
List("volume", "number", "series", "type", "address", "edition", "month", "pages", "note")),
Entry("Proceedings",
List("title", "year"),
List(),
List("booktitle", "editor", "volume", "number", "series", "address", "month",
"organization", "publisher", "note")),
Entry("Book",
List("author", "editor", "title"),
List("publisher", "year"),
List("volume", "number", "series", "address", "edition", "month", "note")),
Entry("Booklet",
List("title"),
List(),
List("author", "howpublished", "address", "month", "year", "note")),
Entry("PhdThesis",
List("author", "title", "school", "year"),
List(),
List("type", "address", "month", "note")),
Entry("MastersThesis",
List("author", "title", "school", "year"),
List(),
List("type", "address", "month", "note")),
Entry("TechReport",
List("author", "title", "institution", "year"),
List(),
List("type", "number", "address", "month", "note")),
Entry("Manual",
List("title"),
List(),
List("author", "organization", "address", "edition", "month", "year", "note")),
Entry("Unpublished",
List("author", "title", "note"),
List(),
List("month", "year")),
Entry("Misc",
List(),
List(),
List("author", "title", "howpublished", "month", "year", "note")))
def get_entry(kind: String): Option[Entry] =
entries.find(entry => entry.kind.toLowerCase == kind.toLowerCase)
def is_entry(kind: String): Boolean = get_entry(kind).isDefined
/** tokens and chunks **/
object Token
{
object Kind extends Enumeration
{
val COMMAND = Value("command")
val ENTRY = Value("entry")
val KEYWORD = Value("keyword")
val NAT = Value("natural number")
val STRING = Value("string")
val NAME = Value("name")
val IDENT = Value("identifier")
val SPACE = Value("white space")
val COMMENT = Value("ignored text")
val ERROR = Value("bad input")
}
}
sealed case class Token(kind: Token.Kind.Value, source: String)
{
def is_kind: Boolean =
kind == Token.Kind.COMMAND ||
kind == Token.Kind.ENTRY ||
kind == Token.Kind.IDENT
def is_name: Boolean =
kind == Token.Kind.NAME ||
kind == Token.Kind.IDENT
def is_ignored: Boolean =
kind == Token.Kind.SPACE ||
kind == Token.Kind.COMMENT
def is_malformed: Boolean = kind ==
Token.Kind.ERROR
}
case class Chunk(kind: String, tokens: List[Token])
{
val source = tokens.map(_.source).mkString
private val content: Option[List[Token]] =
tokens match {
case Token(Token.Kind.KEYWORD, "@") :: body if body.nonEmpty =>
(body.init.filterNot(_.is_ignored), body.last) match {
case (tok :: Token(Token.Kind.KEYWORD, "{") :: toks, Token(Token.Kind.KEYWORD, "}"))
if tok.is_kind => Some(toks)
case (tok :: Token(Token.Kind.KEYWORD, "(") :: toks, Token(Token.Kind.KEYWORD, ")"))
if tok.is_kind => Some(toks)
case _ => None
}
case _ => None
}
def name: String =
content match {
case Some(tok :: _) if tok.is_name => tok.source
case _ => ""
}
def is_ignored: Boolean = kind == "" && tokens.forall(_.is_ignored)
def is_malformed: Boolean = kind == "" || tokens.exists(_.is_malformed)
def is_command: Boolean = Bibtex.is_command(kind) && name != "" && content.isDefined
def is_entry: Boolean = Bibtex.is_entry(kind) && name != "" && content.isDefined
}
/** parsing **/
// context of partial line-oriented scans
abstract class Line_Context
case object Ignored extends Line_Context
case object At extends Line_Context
case class Item_Start(kind: String) extends Line_Context
case class Item_Open(kind: String, end: String) extends Line_Context
case class Item(kind: String, end: String, delim: Delimited) extends Line_Context
case class Delimited(quoted: Boolean, depth: Int)
val Closed = Delimited(false, 0)
private def token(kind: Token.Kind.Value)(source: String): Token = Token(kind, source)
private def keyword(source: String): Token = Token(Token.Kind.KEYWORD, source)
// See also http://ctan.org/tex-archive/biblio/bibtex/base/bibtex.web
// module @<Scan for and process a \.{.bib} command or database entry@>.
object Parsers extends RegexParsers
{
/* white space and comments */
override val whiteSpace = "".r
private val space = """[ \t\n\r]+""".r ^^ token(Token.Kind.SPACE)
private val spaces = rep(space)
/* ignored text */
private val ignored: Parser[Chunk] =
rep1("""(?i)([^@]+|@[ \t]*comment)""".r) ^^ {
case ss => Chunk("", List(Token(Token.Kind.COMMENT, ss.mkString))) }
private def ignored_line: Parser[(Chunk, Line_Context)] =
ignored ^^ { case a => (a, Ignored) }
/* delimited string: outermost "..." or {...} and body with balanced {...} */
// see also bibtex.web: scan_a_field_token_and_eat_white, scan_balanced_braces
private def delimited_depth(delim: Delimited): Parser[(String, Delimited)] =
new Parser[(String, Delimited)]
{
require(if (delim.quoted) delim.depth > 0 else delim.depth >= 0)
def apply(in: Input) =
{
val start = in.offset
val end = in.source.length
var i = start
var q = delim.quoted
var d = delim.depth
var finished = false
while (!finished && i < end) {
val c = in.source.charAt(i)
if (c == '"' && d == 0) { i += 1; d = 1; q = true }
else if (c == '"' && d == 1 && q) {
i += 1; d = 0; q = false; finished = true
}
else if (c == '{') { i += 1; d += 1 }
else if (c == '}') {
if (d == 1 && !q || d > 1) { i += 1; d -= 1; if (d == 0) finished = true }
else {i = start; finished = true }
}
else if (d > 0) i += 1
else finished = true
}
if (i == start) Failure("bad input", in)
else {
val s = in.source.subSequence(start, i).toString
Success((s, Delimited(q, d)), in.drop(i - start))
}
}
}.named("delimited_depth")
private def delimited: Parser[Token] =
delimited_depth(Closed) ^?
{ case (s, delim) if delim == Closed => Token(Token.Kind.STRING, s) }
private def recover_delimited: Parser[Token] =
"""["{][^@]*""".r ^^ token(Token.Kind.ERROR)
def delimited_line(ctxt: Item): Parser[(Chunk, Line_Context)] =
delimited_depth(ctxt.delim) ^^ { case (s, delim1) =>
(Chunk(ctxt.kind, List(Token(Token.Kind.STRING, s))), ctxt.copy(delim = delim1)) } |
recover_delimited ^^ { case a => (Chunk(ctxt.kind, List(a)), Ignored) }
/* other tokens */
private val at = "@" ^^ keyword
private val nat = "[0-9]+".r ^^ token(Token.Kind.NAT)
private val name = """[\x21-\x7f&&[^"#%'(),={}]]+""".r ^^ token(Token.Kind.NAME)
private val identifier =
"""[\x21-\x7f&&[^"#%'(),={}0-9]][\x21-\x7f&&[^"#%'(),={}]]*""".r
private val ident = identifier ^^ token(Token.Kind.IDENT)
val other_token = "[=#,]".r ^^ keyword | (nat | (ident | space))
/* body */
private val body =
delimited | (recover_delimited | other_token)
private def body_line(ctxt: Item) =
if (ctxt.delim.depth > 0)
delimited_line(ctxt)
else
delimited_line(ctxt) |
other_token ^^ { case a => (Chunk(ctxt.kind, List(a)), ctxt) } |
ctxt.end ^^ { case a => (Chunk(ctxt.kind, List(keyword(a))), Ignored) }
/* items: command or entry */
private val item_kind =
identifier ^^ { case a =>
val kind =
if (is_command(a)) Token.Kind.COMMAND
else if (is_entry(a)) Token.Kind.ENTRY
else Token.Kind.IDENT
Token(kind, a)
}
private val item_begin =
"{" ^^ { case a => ("}", keyword(a)) } |
"(" ^^ { case a => (")", keyword(a)) }
private def item_name(kind: String) =
kind.toLowerCase match {
case "preamble" => failure("")
case "string" => identifier ^^ token(Token.Kind.NAME)
case _ => name
}
private val item_start =
at ~ spaces ~ item_kind ~ spaces ^^
{ case a ~ b ~ c ~ d => (c.source, List(a) ::: b ::: List(c) ::: d) }
private val item: Parser[Chunk] =
(item_start ~ item_begin ~ spaces) into
{ case (kind, a) ~ ((end, b)) ~ c =>
opt(item_name(kind)) ~ rep(body) ~ opt(end ^^ keyword) ^^ {
case d ~ e ~ f => Chunk(kind, a ::: List(b) ::: c ::: d.toList ::: e ::: f.toList) } }
private val recover_item: Parser[Chunk] =
at ~ "[^@]*".r ^^ { case a ~ b => Chunk("", List(a, Token(Token.Kind.ERROR, b))) }
/* chunks */
val chunk: Parser[Chunk] = ignored | (item | recover_item)
def chunk_line(ctxt: Line_Context): Parser[(Chunk, Line_Context)] =
{
ctxt match {
case Ignored =>
ignored_line |
at ^^ { case a => (Chunk("", List(a)), At) }
case At =>
space ^^ { case a => (Chunk("", List(a)), ctxt) } |
item_kind ^^ { case a => (Chunk(a.source, List(a)), Item_Start(a.source)) } |
recover_item ^^ { case a => (a, Ignored) } |
ignored_line
case Item_Start(kind) =>
space ^^ { case a => (Chunk(kind, List(a)), ctxt) } |
item_begin ^^ { case (end, a) => (Chunk(kind, List(a)), Item_Open(kind, end)) } |
recover_item ^^ { case a => (a, Ignored) } |
ignored_line
case Item_Open(kind, end) =>
space ^^ { case a => (Chunk(kind, List(a)), ctxt) } |
item_name(kind) ^^ { case a => (Chunk(kind, List(a)), Item(kind, end, Closed)) } |
body_line(Item(kind, end, Closed)) |
ignored_line
case item_ctxt: Item =>
body_line(item_ctxt) |
ignored_line
case _ => failure("")
}
}
}
/* parse */
def parse(input: CharSequence): List[Chunk] =
{
val in: Reader[Char] = new CharSequenceReader(input)
Parsers.parseAll(Parsers.rep(Parsers.chunk), in) match {
case Parsers.Success(result, _) => result
case _ => error("Unexpected failure to parse input:\n" + input.toString)
}
}
def parse_line(input: CharSequence, context: Line_Context): (List[Chunk], Line_Context) =
{
var in: Reader[Char] = new CharSequenceReader(input)
val chunks = new mutable.ListBuffer[Chunk]
var ctxt = context
while (!in.atEnd) {
Parsers.parse(Parsers.chunk_line(ctxt), in) match {
case Parsers.Success((x, c), rest) => chunks += x; ctxt = c; in = rest
case Parsers.NoSuccess(_, rest) =>
error("Unepected failure to parse input:\n" + rest.source.toString)
}
}
(chunks.toList, ctxt)
}
}