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|
open Pdfutil
type t =
{year : int;
month : int;
day : int;
hour : int;
minute : int;
second : int;
hour_offset : int;
minute_offset : int}
exception BadDate
let check_date d =
try
assert (d.year >= 0 && d.year <= 9999);
assert (d.month >= 1 && d.month <= 12);
assert (d.day >= 1 && d.day <= 31);
assert (d.hour >= 0 && d.hour <= 23);
assert (d.minute >= 0 && d.minute <= 59);
assert (d.second >= 0 && d.second <= 59);
assert (d.hour_offset >= -23 && d.hour_offset <= 23);
assert (d.minute_offset >= -59 && d.minute_offset <= 59);
with
_ -> raise BadDate
(* For now, no detection of default values which could be omitted. *)
let string_of_date d =
check_date d;
let ostr =
if d.hour_offset < 0 then
Printf.sprintf "-%02i'%02i'" (abs d.hour_offset) (abs d.minute_offset)
else if d.hour_offset > 0 then
Printf.sprintf "+%02i'%02i'" (abs d.hour_offset) (abs d.minute_offset)
else "Z"
in
Printf.sprintf
"D:%04i%02i%02i%02i%02i%02i%s"
d.year d.month d.day d.hour d.minute d.second ostr
let date_of_string s =
let safe_int_string chars =
try int_of_string (implode chars) with
_ -> raise BadDate
in
let hour_offset = ref 0
in let minute_offset = ref 0
in let o = ref 0 in
let rec optional_twochar def cs =
match cs with
| ('-' | '+' | 'Z')::_ ->
parse_local_time cs;
def, []
| a::b::more -> safe_int_string [a;b], more
| _ -> def, []
and parse_local_time cs =
let o_got, cs =
match cs with
| '+'::more -> 1, more
| '-'::more -> -1, more
| 'Z'::more -> 0, more
| _ -> 0, []
in
let h, cs = optional_twochar 0 cs in
match cs with
| [] -> ()
| _ ->
let m, cs = optional_twochar 0 (tl cs) in
hour_offset := h;
minute_offset := m;
o := o_got
in
let cs = explode s in
let cs =
match cs with
| 'D'::':'::more -> more
| _ -> cs
in
let year, cs =
match cs with
| '1'::'9'::'1'::'0'::'0'::more -> 2000, more (* Adobe Distiller 3 Y2K Bug *)
| a::b::c::d::more -> safe_int_string [a;b;c;d], more
| _ -> raise BadDate
in
let month, cs = optional_twochar 1 cs in
let day, cs = optional_twochar 1 cs in
let hour, cs = optional_twochar 0 cs in
let minute, cs = optional_twochar 0 cs in
let second, cs = optional_twochar 0 cs in
parse_local_time cs;
let date =
{year = year;
month = month;
day = day;
hour = hour;
minute = minute;
second = second;
hour_offset = !hour_offset * !o;
minute_offset = !minute_offset * !o}
in
check_date date;
date
|
