gui/gui-lib/framework/private/aspell.rkt
2014-12-02 02:33:07 -05:00

239 lines
9.4 KiB
Racket

#lang racket/base
(require racket/system
racket/match
racket/contract
racket/port
string-constants)
(provide/contract
[query-aspell (->* ((and/c string? (not/c #rx"[\n]")))
((or/c #f string?))
(listof (list/c number? number? (listof string?))))]
;; may return #f when aspell is really ispell or when
;; something goes wrong trying to get the list of dictionaries
[get-aspell-dicts (-> (or/c #f (listof string?)))]
[find-aspell-binary-path (-> (or/c path? #f))]
[aspell-problematic? (-> (or/c string? #f))])
(define aspell-candidate-paths
'("/usr/bin"
"/bin"
"/usr/local/bin"
"/opt/local/bin/"))
(define (find-aspell-binary-path)
(define aspell (if (eq? (system-type) 'windows) "aspell.exe" "aspell"))
(define ispell (if (eq? (system-type) 'windows) "ispell.exe" "ispell"))
(or (find-executable-path aspell)
(find-executable-path ispell)
(for/or ([cp aspell-candidate-paths])
(define c1 (build-path cp aspell))
(define c2 (build-path cp ispell))
(or (and (file-exists? c1)
c1)
(and (file-exists? c2)
c2)))))
(define (start-aspell asp dict)
(define aspell? (regexp-match? #rx"aspell" (path->string asp)))
(apply process* asp
(append
'("-a")
(if dict
(list "-d" dict)
'())
(if aspell? '("--encoding=utf-8") '()))))
(define problematic 'dont-know)
(define (aspell-problematic?)
(when (eq? problematic 'dont-know)
(set! problematic (do-aspell-problematic))
(asp-log (format "set problematic to ~s" problematic)))
problematic)
(define (do-aspell-problematic)
(define asp (find-aspell-binary-path))
(cond
[(not asp)
(string-constant cannot-find-ispell-or-aspell-path)]
[else
(define proc-lst (start-aspell asp #f))
(define stdout (list-ref proc-lst 0))
(define stderr (list-ref proc-lst 3))
(close-output-port (list-ref proc-lst 1)) ;; close stdin
(close-input-port stdout)
(define sp (open-output-string))
(copy-port stderr sp)
(define errmsg (get-output-string sp))
(close-input-port stderr)
(cond
[(not (equal? errmsg ""))
(string-append
(format (string-constant spell-program-wrote-to-stderr-on-startup) asp)
"\n\n"
errmsg)]
[else #f])]))
(define asp-logger (make-logger 'framework/aspell (current-logger)))
(define-syntax-rule
(asp-log arg)
(when (log-level? asp-logger 'debug)
(asp-log/proc arg)))
(define (asp-log/proc arg)
(log-message asp-logger 'debug arg (current-continuation-marks)))
(define aspell-req-chan (make-channel))
(define change-dict-chan (make-channel))
(define aspell-thread #f)
(define (start-aspell-thread)
(unless aspell-thread
(set! aspell-thread
(thread
(λ ()
(define aspell-proc #f)
(define already-attempted-aspell? #f)
(define current-dict #f)
(define (fire-up-aspell)
(unless already-attempted-aspell?
(set! already-attempted-aspell? #t)
(define asp (find-aspell-binary-path))
(when asp
(set! aspell-proc (start-aspell asp current-dict))
(define line (with-handlers ((exn:fail? exn-message))
(read-line (list-ref aspell-proc 0))))
(asp-log (format "framework: started speller: ~a" line))
(when (and (string? line)
(regexp-match #rx"[Aa]spell" line))
;; put aspell in "terse" mode
(display "!\n" (list-ref aspell-proc 1))
(flush-output (list-ref aspell-proc 1)))
(define stderr (list-ref aspell-proc 3))
(thread
(λ ()
(let loop ()
(define l (with-handlers ((exn:fail? void))
(read-line stderr)))
(when (string? l)
(asp-log (format "aspell-proc stderr: ~a" l))
(loop))))))))
(define (shutdown-aspell why)
(asp-log (format "aspell.rkt: shutdown connection to aspell: ~a" why))
(define proc (list-ref aspell-proc 4))
(close-input-port (list-ref aspell-proc 0))
(close-output-port (list-ref aspell-proc 1))
(close-input-port (list-ref aspell-proc 3))
(proc 'kill)
(set! aspell-proc #f))
(let loop ()
(sync
(handle-evt
aspell-req-chan
(match-lambda
[(list line new-dict resp-chan nack-evt)
(unless (equal? new-dict current-dict)
(when aspell-proc
(shutdown-aspell "changing dictionary")
(set! already-attempted-aspell? #f))
(set! current-dict new-dict))
(unless aspell-proc (fire-up-aspell))
(define (send-resp resp)
(sync (channel-put-evt resp-chan resp)
nack-evt))
(cond
[aspell-proc
(define stdout (list-ref aspell-proc 0))
(define stdin (list-ref aspell-proc 1))
;; always lead with a ^ character so aspell
;; doesn't interpret anything as a command
(display "^" stdin)
(display line stdin)
(newline stdin)
(flush-output stdin)
(let loop ([resp '()])
(define check-on-aspell (sync/timeout .5 stdout))
(cond
[check-on-aspell
(define (handle-err x)
(asp-log
(format "error reading stdout of aspell process: ~a"
(exn-message x)))
eof)
(define l (with-handlers ((exn:fail? handle-err))
(read-line stdout)))
(cond
[(eof-object? l)
(send-resp '())
(shutdown-aspell "got eof from process")]
[(equal? l "") (send-resp (reverse resp))]
[(regexp-match #rx"^[*]" l) (loop resp)]
[(regexp-match #rx"^[&] ([^ ]*) [0-9]+ ([0-9]+): (.*)$" l)
=>
(λ (m)
(define word-len (string-length (list-ref m 1)))
;; subtract one to correct for the leading ^
(define word-start (- (string->number (list-ref m 2)) 1))
(define suggestions (list-ref m 3))
(loop
(cons
(list word-start word-len (regexp-split #rx", " suggestions))
resp)))]
[(regexp-match #rx"^[#] ([^ ]*) ([0-9]+)" l)
=>
(λ (m)
(define word-len (string-length (list-ref m 1)))
;; subtract one to correct for the leading ^
(define word-start (- (string->number (list-ref m 2)) 1))
(loop (cons (list word-start word-len '()) resp)))]
[else
(send-resp '())
(shutdown-aspell (format "could not parse aspell output line: ~s" l))])]
[else
(send-resp '())
(shutdown-aspell "interaction timed out")]))]
[else (send-resp '())])
(loop)])))))))))
(define (query-aspell line [dict #f])
(cond
[(aspell-problematic?)
'()]
[else
(when dict
(unless (member dict (get-aspell-dicts))
(set! dict #f)))
(start-aspell-thread)
(sync
(nack-guard-evt
(λ (nack-evt)
(define resp (make-channel))
(channel-put aspell-req-chan (list line dict resp nack-evt))
resp)))]))
(define aspell-dicts #f)
(define (get-aspell-dicts)
(unless (aspell-problematic?)
(unless aspell-dicts
(define asp (find-aspell-binary-path))
(when (regexp-match? #rx"aspell" (path->string asp))
(define proc-lst (process* asp "dump" "dicts"))
(define stdout (list-ref proc-lst 0))
(define stderr (list-ref proc-lst 3))
(close-output-port (list-ref proc-lst 1)) ;; close stdin
(close-input-port stderr)
(set! aspell-dicts
(let loop ()
(define l (read-line stdout))
(cond
[(eof-object? l) '()]
[else (cons l (loop))]))))))
aspell-dicts)