255 lines
9.9 KiB
OCaml
255 lines
9.9 KiB
OCaml
open Pdfutil
|
|
|
|
(* Raised when syntax is ok, but endpage is too low. Caught by validator.
|
|
Caught and reraised as normal failure by parse_pagespec. *)
|
|
exception PageSpecUnknownPage of int
|
|
|
|
(* There would be no pages *)
|
|
exception PageSpecWouldBeNoPages
|
|
|
|
(* Raised when syntax is wrong. Caught and reraised by parse_pagespec and
|
|
validator. *)
|
|
exception PageSpecBadSyntax
|
|
|
|
(* Parsing range specifications *)
|
|
let rec splitat_commas toks =
|
|
match cleavewhile (neq (Pdfgenlex.LexName ",")) toks with
|
|
| [], [] -> []
|
|
| [], _ -> raise PageSpecBadSyntax
|
|
| some, [] -> [some]
|
|
| _::_ as before, _::rest -> before::splitat_commas rest
|
|
|
|
let is_dimension pdf comparison {Pdfpage.mediabox = box} =
|
|
let minx, miny, maxx, maxy = Pdf.parse_rectangle pdf box in
|
|
comparison (maxx -. minx) (maxy -. miny)
|
|
|
|
let select_dimensions comparison pdf candidates =
|
|
let pages = Pdfpage.pages_of_pagetree pdf in
|
|
let pagenums, kept_pages =
|
|
split
|
|
(option_map
|
|
(fun (index, page) ->
|
|
if mem index candidates then Some (index, page) else None)
|
|
(combine (indx pages) pages))
|
|
in
|
|
option_map2
|
|
(fun pagenum page ->
|
|
if is_dimension pdf comparison page then Some pagenum else None)
|
|
pagenums
|
|
kept_pages
|
|
|
|
let select_portrait = select_dimensions ( < )
|
|
|
|
let select_landscape = select_dimensions ( > )
|
|
|
|
let rec mk_numbers pdf endpage lexemes =
|
|
match lexemes with
|
|
| [Pdfgenlex.LexInt n] -> [n]
|
|
| [Pdfgenlex.LexName "end"] -> [endpage]
|
|
| [Pdfgenlex.LexInt n; Pdfgenlex.LexName "-"; Pdfgenlex.LexInt n'] ->
|
|
if n > n' then rev (ilist n' n) else ilist n n'
|
|
| [Pdfgenlex.LexName "end"; Pdfgenlex.LexName "-"; Pdfgenlex.LexInt n] ->
|
|
if n <= endpage
|
|
then rev (ilist n endpage)
|
|
else raise (PageSpecUnknownPage n)
|
|
| [Pdfgenlex.LexInt n; Pdfgenlex.LexName "-"; Pdfgenlex.LexName "end"] ->
|
|
if n <= endpage
|
|
then ilist n endpage
|
|
else raise (PageSpecUnknownPage n)
|
|
| [Pdfgenlex.LexName "end"; Pdfgenlex.LexName "-"; Pdfgenlex.LexName "end"] ->
|
|
[endpage]
|
|
| [Pdfgenlex.LexName "even"] ->
|
|
drop_odds (ilist 1 endpage)
|
|
| [Pdfgenlex.LexName "portrait"] ->
|
|
select_portrait pdf (ilist 1 endpage)
|
|
| [Pdfgenlex.LexName "landscape"] ->
|
|
select_landscape pdf (ilist 1 endpage)
|
|
| [Pdfgenlex.LexName "odd"] ->
|
|
really_drop_evens (ilist 1 endpage)
|
|
| [Pdfgenlex.LexName "all"] ->
|
|
ilist 1 endpage
|
|
| [Pdfgenlex.LexName "reverse"] ->
|
|
rev (ilist 1 endpage)
|
|
| toks ->
|
|
let ranges = splitat_commas toks in
|
|
if ranges = [toks] then raise PageSpecBadSyntax else
|
|
flatten (map (mk_numbers pdf endpage) ranges)
|
|
|
|
(* Space dashes and commas *)
|
|
let rec add_spaces = function
|
|
| [] -> []
|
|
| ('-' | ',') as h::t -> ' '::h::' '::add_spaces t
|
|
| h::t -> h::add_spaces t
|
|
|
|
let space_string s =
|
|
implode (add_spaces (explode s))
|
|
|
|
let fixup_negatives endpage = function
|
|
| Pdfgenlex.LexName s when String.length s > 1 && s.[0] = '~' ->
|
|
Pdfgenlex.LexInt (endpage + 1 + ~-(int_of_string (implode (tl (explode s)))))
|
|
| x -> x
|
|
|
|
let invert_range endpage r =
|
|
option_map (fun p -> if mem p r then None else Some p) (ilist 1 endpage)
|
|
|
|
let duplicate_range n r =
|
|
flatten (map (fun x -> many x n) r)
|
|
|
|
(* e.g <1> -> 1, <iii> -> x, </>> -> > etc. *)
|
|
let resolve_pagelabels pdf spec =
|
|
let labels =
|
|
let labs = Pdfpagelabels.read pdf in
|
|
map
|
|
(fun pnum -> (Pdfpagelabels.pagelabeltext_of_pagenumber pnum labs, pnum))
|
|
(ilist 1 (Pdfpage.endpage pdf))
|
|
in
|
|
(*iter (fun (s, l) -> Printf.printf "%s = %i\n" s l) labels;*)
|
|
let rec resolve_pagelabels_inner = function
|
|
| '<'::t ->
|
|
let pagelabel, rest = cleavewhile (neq '>') t in
|
|
let resolved = explode (string_of_int (begin match lookup (implode pagelabel) labels with Some x -> x | None -> 0 end)) in
|
|
if rest = [] then resolved else resolved @ resolve_pagelabels_inner (tl rest)
|
|
| '\\'::('<' | '>' as c)::t -> c::resolve_pagelabels_inner t
|
|
| '>'::t -> raise PageSpecBadSyntax
|
|
| h::t -> h::resolve_pagelabels_inner t
|
|
| [] -> []
|
|
in
|
|
resolve_pagelabels_inner spec
|
|
|
|
let rec parse_pagespec_inner endpage pdf spec =
|
|
let spec = if spec = "" then "all" else spec in
|
|
(*let spec = implode (resolve_pagelabels pdf (explode spec)) in*)
|
|
let spec = space_string spec in
|
|
if endpage < 1 then raise (Pdf.PDFError "This PDF file has no pages and is therefore malformed") else
|
|
let numbers =
|
|
try
|
|
match explode spec with
|
|
| 'N'::'O'::'T'::r ->
|
|
invert_range endpage (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::y::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x; y])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::y::z::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x; y; z])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::y::z::a::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x; y; z; a])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::y::z::a::b::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x; y; z; a; b])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| x::y::z::a::b::c::'D'::'U'::'P'::r ->
|
|
duplicate_range (int_of_string (implode [x; y; z; a; b; c])) (parse_pagespec_inner endpage pdf (implode r))
|
|
| _ ->
|
|
match rev (explode spec) with
|
|
| ['n'; 'e'; 'v'; 'e'] ->
|
|
keep even (ilist 1 endpage)
|
|
| ['d'; 'd'; 'o'] ->
|
|
keep odd (ilist 1 endpage)
|
|
| ['t'; 'i'; 'a'; 'r'; 't'; 'r'; 'o'; 'p'] ->
|
|
select_portrait pdf (ilist 1 endpage)
|
|
| ['e'; 'p'; 'a'; 'c'; 's'; 'd'; 'n'; 'a'; 'l'] ->
|
|
select_landscape pdf (ilist 1 endpage)
|
|
| 't'::'i'::'a'::'r'::'t'::'r'::'o'::'p'::more ->
|
|
select_portrait
|
|
pdf
|
|
(mk_numbers pdf endpage (map (fixup_negatives endpage) (Pdfgenlex.lex_string (implode (rev more)))))
|
|
| 'e'::'p'::'a'::'c'::'s'::'d'::'n'::'a'::'l'::more ->
|
|
select_landscape
|
|
pdf
|
|
(mk_numbers pdf endpage (map (fixup_negatives endpage) (Pdfgenlex.lex_string (implode (rev more)))))
|
|
| 'd'::'d'::'o'::more ->
|
|
keep
|
|
odd
|
|
(mk_numbers pdf endpage (map (fixup_negatives endpage) (Pdfgenlex.lex_string (implode (rev more)))))
|
|
| 'n'::'e'::'v'::'e'::more ->
|
|
keep
|
|
even
|
|
(mk_numbers pdf endpage (map (fixup_negatives endpage) (Pdfgenlex.lex_string (implode (rev more)))))
|
|
| _ ->
|
|
mk_numbers pdf endpage (map (fixup_negatives endpage) (Pdfgenlex.lex_string spec))
|
|
with
|
|
e -> raise PageSpecBadSyntax
|
|
in
|
|
if numbers = [] then raise PageSpecWouldBeNoPages else
|
|
iter
|
|
(fun n ->
|
|
if n <= 0 || n > endpage then raise (PageSpecUnknownPage n))
|
|
numbers;
|
|
numbers
|
|
|
|
let parse_pagespec pdf spec =
|
|
try parse_pagespec_inner (Pdfpage.endpage pdf) pdf spec with
|
|
| PageSpecUnknownPage n ->
|
|
raise (Pdf.PDFError ("Page " ^ string_of_int n ^ " does not exist."))
|
|
| PageSpecWouldBeNoPages ->
|
|
raise (Pdf.PDFError ("Page range specifies no pages"))
|
|
| e ->
|
|
raise
|
|
(Pdf.PDFError
|
|
("Bad page specification " ^ spec ^
|
|
". Raw error was " ^ Printexc.to_string e ^
|
|
". Last page was " ^ string_of_int (Pdfpage.endpage pdf)))
|
|
|
|
(* To validate a pagespec as being syntactically correct without the PDF in
|
|
question. This is nasty, since the parser above includes checking based on the
|
|
endpage of the PDF (which we don't have). Pass 100 as the endpage, doubling on
|
|
page range exception, bailng out above 500000. *)
|
|
let rec validate_pagespec_inner n spec =
|
|
try
|
|
ignore (parse_pagespec_inner n (Pdf.empty ()) spec); true
|
|
with
|
|
| PageSpecUnknownPage _ -> if n < 500000 then validate_pagespec_inner (n * 2) spec else false
|
|
| PageSpecBadSyntax | _ -> false
|
|
|
|
let validate_pagespec spec =
|
|
validate_pagespec_inner 100 spec
|
|
|
|
let rec parse_pagespec_without_pdf_inner n spec =
|
|
try
|
|
parse_pagespec_inner n (Pdf.empty ()) spec
|
|
with
|
|
PageSpecUnknownPage _ ->
|
|
if n < 500000
|
|
then parse_pagespec_without_pdf_inner (n * 2) spec
|
|
else raise (Pdf.PDFError "PageSpecUnknownPage")
|
|
|
|
let parse_pagespec_without_pdf spec =
|
|
parse_pagespec_without_pdf_inner 100 spec
|
|
|
|
(* Convert an integer list representing a set to a page specification, in order. *)
|
|
let string_of_pagespec pdf = function
|
|
| [] -> ""
|
|
| is ->
|
|
let iseven len is =
|
|
drop_odds (ilist 1 len) = is
|
|
in let isodd len is =
|
|
really_drop_evens (ilist 1 len) = is
|
|
in let isall len is =
|
|
ilist 1 len = is
|
|
in let is = sort compare is
|
|
in let len = Pdfpage.endpage pdf in
|
|
let rec mkranges prev = function
|
|
| [] -> map extremes (rev (map rev prev))
|
|
| h::t ->
|
|
match prev with
|
|
| (ph::pht)::pt when h = ph + 1 -> mkranges ((h::ph::pht)::pt) t
|
|
| (_::_)::_ -> mkranges ([h]::prev) t
|
|
| []::_ -> assert false
|
|
| [] -> mkranges [[h]] t
|
|
in
|
|
if iseven len is && len > 3 then "even" else
|
|
if isodd len is && len > 2 then "odd" else
|
|
if isall len is then "all" else
|
|
let ranges = mkranges [] is in
|
|
let rangestrings =
|
|
map
|
|
(function (s, e) ->
|
|
if s = e
|
|
then string_of_int s
|
|
else string_of_int s ^ "-" ^ string_of_int e)
|
|
ranges
|
|
in
|
|
fold_left ( ^ ) "" (interleave "," rangestrings)
|
|
|
|
let string_of_range r =
|
|
fold_left (fun a b -> a ^ " " ^ b) "" (map string_of_int r)
|