scsh-ncurses/scheme/input-buffer.scm

448 lines
14 KiB
Scheme
Raw Blame History

;;This is an application of the "scsh-ncurses" lib.
;;It consists of a buffer with input.
;;
;;At the beginning we only have an empty buffer for example.
;;You pass this buffer an char after char to the input-function,
;;which modifies the content of the buffer. In the standard-case
;;you get the characters from "wgetch".
;;
;;One brief example:
; ;
; ;
; ; (begin
; ; (define my-buffer (make-buffer-welcome 20 20 "test"))
; ; (init-screen)
; ; (define win (newwin 20 20 5 5))
; ; (box win (ascii->char 0) (ascii->char 0))
; ; (noecho)
; ; (keypad win #t)
; ; (set! my-buffer (print-command-buffer win my-buffer))
; ; (let loop ((ch (wgetch win)))
; ; (begin
; ; (wclear win)
; ; (box win (ascii->char 0) (ascii->char 0))
; ; (set! my-buffer (input my-buffer ch))
; ; (set! my-buffer (print-command-buffer win my-buffer))
; ; (if (= ch key-f1)
; ; (begin
; ; (echo)
; ; (endwin))
; ; (begin
; ; (set! my-buffer (cursor-right-pos win my-buffer))
; ; (loop (wgetch win)))))))
;;It is very esential, that you set keypad to true und call noecho!!!
(define first-column 2)
;;record-type buffer
(define-record-type buffer :buffer
(make-buffer text
pos-line ;; Cursor-Position auf text bezogen
pos-col
pos-fin-ln ;; ???
pos-y ;; Cursor relativ zum Fenster
pos-x
num-lines
num-cols
can-write
history-pos)
(text buffer-text set-buffer-text!)
(pos-line buffer-pos-line set-buffer-pos-line!)
(pos-col buffer-pos-col set-buffer-pos-col!)
(pos-fin-ln buffer-pos-fin-ln set-buffer-pos-fin-ln!)
(pos-y buffer-pos-y set-buffer-pos-y!)
(pos-x buffer-pos-x set-buffer-pos-x!)
(num-lines buffer-num-lines set-buffer-num-lines!)
(num-cols buffer-num-cols set-buffer-num-cols!)
(can-write buffer-can-write set-buffer-can-write!)
(history-pos buffer-history-pos set-buffer-history-pos!))
(define-record-discloser :buffer
(lambda (rec)
`(buffer ,@(map (lambda (p)
(cons (car p) ((cdr p) rec)))
`((pos-line . ,buffer-pos-line)
(pos-col . ,buffer-pos-col)
(pos-fin-ln . ,buffer-pos-fin-ln)
(pos-y . ,buffer-pos-y)
(pos-x . ,buffer-pos-x)
(history-pos . ,buffer-history-pos)
(lines . ,(lambda (b) (length (buffer-text b)))))))))
(define (buffer-text-current-line buffer)
(list-ref (buffer-text buffer)
(- (buffer-pos-line buffer) 1)))
(define (buffer-text-append-new-line! buffer)
(set-buffer-text! buffer
(append (buffer-text buffer)
(list ""))))
;;handle input
(define (input buffer ch)
(cond
;; enter key
((= ch 10)
(set-buffer-text! buffer
(append (buffer-text buffer) (list "")))
(set-buffer-pos-line! buffer
(+ (buffer-pos-line buffer) 1))
(set-buffer-pos-col! buffer first-column)
(set-buffer-history-pos! buffer
(- (length (buffer-text buffer)) 1)))
;; backspace
((and (= ch key-backspace)
(buffer-can-write buffer)
(not (< (buffer-pos-col buffer) 3)))
(set-buffer-text! buffer
(remove-from-command-buffer
(buffer-text buffer)
(buffer-pos-col buffer)))
(regress-buffer-cursor-column! buffer))
;; FIXME
;; move cursor to previous line Ctrl-p, keycode 16
; ((= ch 16)
; (if (< pos-fin-ln 2)
; (values)
; (let ((length-prev-line
; (string-length
; (list-ref text (- pos-line 2)))))
; (set! can-write #f)
; (set! pos-line (- pos-line 1))
; (set! pos-col (+ length-prev-line 2)))))
;; FIXME
;; move cursor to next line Ctrl-n, keycode 141
; ((= ch 141)
; (let ((last-pos (length text)))
; (if (>= pos-line last-pos)
; (values)
; (let ((length-next-line
; (string-length
; (list-ref text pos-line))))
; (begin
; (set! pos-col (+ length-next-line 2))
; (set! pos-line (+ pos-line 1))
; (if (= pos-line last-pos)
; (set! can-write #t)))))))
;; CursorLeft
((and (= ch key-left)
(> (buffer-pos-col buffer) first-column))
(regress-buffer-cursor-column! buffer))
;; CursorRight
((= ch key-right)
(let ((line-length (string-length
(buffer-text-current-line buffer))))
(if (< (buffer-pos-col buffer) (+ line-length first-column))
(advance-buffer-cursor-column! buffer))))
;;Ctrl+a -> Pos 1
((= ch 1)
(set-buffer-pos-col! buffer first-column))
;;Ctrl-e -> End
((= ch 5)
(let ((line-length (string-length
(buffer-text-current-line buffer))))
(set-buffer-pos-col! buffer
(+ line-length first-column))))
;; Ctrl+k -> Zeile l<>schen
((and (= ch 11)
(buffer-can-write buffer))
(let ((text-front (sublist (buffer-text buffer)
0 (- (length (buffer-text buffer)) 1))))
(set-buffer-text! buffer (append text-front '("")))
(set-buffer-pos-col! buffer first-column)))
;; forward in command history -- CursorDown
((and (= ch key-down)
(buffer-can-write buffer))
(if (< (buffer-history-pos buffer)
(- (length (buffer-text buffer)) 1))
(set-buffer-history-pos! buffer
(+ (buffer-history-pos buffer) 1)))
(let ((rest (sublist (buffer-text buffer) 0
(- (length (buffer-text buffer)) 1)))
(hist (if (= (buffer-history-pos buffer)
(- (length (buffer-text buffer)) 1))
""
(list-ref (buffer-text buffer)
(buffer-history-pos buffer)))))
(set-buffer-text! buffer (append rest (list hist)))
(let ((line-length
(string-length
(list-ref (buffer-text buffer)
(- (length (buffer-text buffer)) 1)))))
(set-buffer-pos-col! buffer (+ line-length first-column)))))
;; back in command history -- CursorUp
((and (= ch key-up)
(buffer-can-write buffer))
(if (> (buffer-history-pos buffer) 0)
(set-buffer-history-pos! buffer
(- (buffer-history-pos buffer) 1)))
(let ((rest (sublist (buffer-text buffer) 0
(- (length (buffer-text buffer)) 1)))
(hist (list-ref (buffer-text buffer)
(buffer-history-pos buffer))))
(set-buffer-text! buffer
(append rest (list hist))))
(let ((line-length (string-length
(list-ref (buffer-text buffer)
(- (length (buffer-text buffer)) 1)))))
(set-buffer-pos-col! buffer (+ line-length first-column))))
((and (buffer-can-write buffer) (<= ch 255))
(append-char-to-buffer! ch buffer)
(advance-buffer-cursor-column! buffer))
(values)))
;;print content of the buffer into the specified window
(define (print-command-buffer win buffer)
(call-with-values
(lambda ()
(get-right-command-lines buffer))
(lambda (lines new-pos-fin-ln)
(set-buffer-pos-fin-ln! buffer new-pos-fin-ln)
(let lp ((lines lines) (line-count 0))
(if (or (null? lines)
(> line-count (buffer-num-lines buffer)))
(values)
(begin
(mvwaddstr win line-count 1 (car lines))
(lp (cdr lines) (+ line-count 1))))))))
;;compute the visible lines
(define (get-right-command-lines buffer)
(call-with-values
(lambda ()
(all-commands-seperated buffer))
(lambda (all-lines-seperated pos-fin-ln)
(let ((num-all-lines (length all-lines-seperated))
(num-lines (buffer-num-lines buffer)))
(if (>= pos-fin-ln num-lines)
;;aktive Zeile ist die unterste
(values (sublist all-lines-seperated
(- pos-fin-ln num-lines)
num-lines)
pos-fin-ln)
(if (<= num-all-lines num-lines)
;;noch keine ganze Seite im Buffer
(values (prepare-lines all-lines-seperated
num-lines (- pos-fin-ln 1))
pos-fin-ln)
;;scrollen auf der ersten Seite
(values (sublist all-lines-seperated 0 num-lines)
pos-fin-ln)))))))
;;seperate all statements
(define (all-commands-seperated buffer)
(let ((num-cols (buffer-num-cols buffer))
(pos-fin-ln (buffer-pos-fin-ln buffer))
(commands (buffer-text buffer)))
(let loop ((act-pos 1) (new '()))
(if (= act-pos (buffer-pos-line buffer))
(let* ((length-new (length new))
(first-el-old (list-ref commands (- act-pos 1)))
(seperated-act (seperate-line-com
first-el-old num-cols))
(length-act (length seperated-act)))
(set! pos-fin-ln (+ length-new length-act))))
(if (> act-pos (length commands))
(values (reverse new) pos-fin-ln)
(let* ((first-el-old (list-ref commands (- act-pos 1)))
(seperated-fst-el-old
(seperate-line-com first-el-old num-cols)))
(loop (+ act-pos 1) (append seperated-fst-el-old new)))))))
;;seperate one statement
(define (seperate-line-com line width)
(let loop ((new '())
(old line))
(if (> width (string-length old))
(if (= 0 (string-length old))
(if (equal? new '())
(add-prompts '(""))
(add-prompts new))
;new
(add-prompts (append (list old) new)))
;(append (list old) new))
(let ((next-line (substring old 0 width))
(rest-old (substring old width (string-length old))))
(loop (cons next-line new) rest-old)))))
;;add ">"
(define (add-prompts l)
(let* ((lr (reverse l))
(old-first-el (list-ref lr 0))
(new-first-el (string-append ">" old-first-el))
(old-rest (list-tail lr 1)))
(let loop ((old old-rest)
(new (list new-first-el)))
(if (> (length old) 0)
(let* ((old-first-el (list-ref old 0))
(new-first-el (string-append " " old-first-el)))
(loop (list-tail old 1) (append new (list new-first-el))))
(reverse new)))))
;;Find the lines to print
(define (prepare-lines l height pos)
(if (< (length l) height)
;; Liste zu kurz -> ""s hinzuf<75>gen
(let loop ((tmp-list l))
(if (= height (length tmp-list))
tmp-list
(loop (append tmp-list (list "")))))
;; Teilliste holen
(if (< pos height)
;;pos nicht ganz unten
(sublist l 0 height)
;;standard-Fall
(sublist l (- pos height) height))))
;;Cursor
;;Put Cursor to the right position
(define (cursor-right-pos win buffer)
(let ((text-index (- (buffer-pos-col buffer) first-column))
(pos-fin-ln (buffer-pos-fin-ln buffer))
(pos-x (buffer-pos-x buffer))
(num-lines (buffer-num-lines buffer))
(num-cols (buffer-num-cols buffer)))
;; y position
(let* ((item-length (string-length (buffer-text-current-line buffer)))
(no-wrapped-lines (quotient item-length num-cols))
(first-line-offset (quotient text-index num-cols))
(new-y (- (+ (- pos-fin-ln no-wrapped-lines)
first-line-offset)
1)))
; (debug-message "num-cols "
; num-cols
; " no-wrapped-lines "
; no-wrapped-lines
; " first-line-offset "
; first-line-offset
; " new-y " new-y
; " length "
; item-length
; " pos-fin-ln "
; pos-fin-ln
; " text-index "
; text-index
; " pos-line "
; (buffer-pos-line buffer)
; " num-lines "
; num-lines)
; (if (and (not (zero? text-index))
; (zero? (remainder text-index num-cols))
; (= text-index item-length))
; (set-buffer-pos-y! buffer (+ new-y 1))
; (set-buffer-pos-y! buffer new-y))
(cond
((and (>= new-y num-lines)
(not (zero? text-index))
(zero? (remainder text-index num-cols))
(= text-index item-length))
(set-buffer-pos-y! buffer num-lines))
((and (>= new-y num-lines)
(< text-index item-length))
(set-buffer-pos-y! buffer
(- num-lines
(- (+ no-wrapped-lines 1)
first-line-offset))))
((>= new-y num-lines)
(set-buffer-pos-y! buffer (- num-lines 1)))
((and (not (zero? text-index))
(zero? (remainder text-index num-cols))
(= text-index item-length))
(set-buffer-pos-y! buffer (+ new-y 1)))
(else
(set-buffer-pos-y! buffer new-y)))
;; x position
(set-buffer-pos-x! buffer (+ first-column
(modulo text-index num-cols)))
; (debug-message "cursor position "
; (buffer-pos-x buffer)
; " "
; (buffer-pos-y buffer))
; (debug-message "num-cols " num-cols
; " pos-col " pos-col
; " text '" (buffer-text-current-line buffer) "'")
(wmove win (buffer-pos-y buffer) (buffer-pos-x buffer)))))
(define (advance-buffer-cursor-column! buffer)
(set-buffer-pos-col! buffer
(+ 1 (buffer-pos-col buffer))))
(define (regress-buffer-cursor-column! buffer)
(set-buffer-pos-col! buffer
(- (buffer-pos-col buffer) 1)))
;; add one character to the buffer
(define (append-char-to-buffer! ch buffer)
(let* ((text (buffer-text buffer))
(pos-col (buffer-pos-col buffer))
(last-pos (- (length text) 1))
(old-last-el (list-ref text last-pos))
(old-rest (sublist text 0 last-pos))
(before-ch (substring old-last-el 0
(max 0 (- pos-col 2))))
(after-ch (substring old-last-el
(max 0 (- pos-col 2))
(string-length old-last-el)))
(new-last-el (string-append before-ch
(string (ascii->char ch))
after-ch)))
(set-buffer-text! buffer
(append old-rest (list new-last-el)))))
;;Remove one character from the line (backspace)
(define remove-from-command-buffer
(lambda (text pos-col)
(let* ((last-pos (- (length text) 1))
(old-last-el (list-ref text last-pos))
(old-rest (sublist text 0 last-pos))
(before-ch (substring old-last-el 0
(max 0 (- pos-col 3))))
(after-ch (if (= pos-col
(+ (string-length old-last-el) 2))
""
(substring old-last-el
(max 0 (- pos-col 2))
(string-length old-last-el))))
(new-last-el (if (= pos-col
(+ (string-length old-last-el) 2))
before-ch
(string-append before-ch after-ch))))
(append old-rest (list new-last-el)))))
(define (sublist l pos k)
(let ((tmp (list-tail l pos)))
(reverse (list-tail (reverse tmp)
(- (length tmp) k)))))
;;Create a fitting buffer for a window with box and a welcome-Message
;;If the message is "", the buffer starts in line one
(define (make-buffer-welcome height width welcome-message)
(if (string=? "" welcome-message)
(make-buffer (list "") 1 2 1 1 2 (- height 2) (- width 3) #t 1)
(make-buffer (list welcome-message "") 2 2 2 2 2
(- height 2) (- width 3) #t 1) ))