;; Copyright © 2024 Jaidyn Ann <jadedctrl@posteo.at>
;;
;; This program is free software: you can redistribute it and/or
;; modify it under the terms of the GNU General Public License as
;; published by the Free Software Foundation, either version 3 of
;; the License, or (at your option) any later version.
;;
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with this program. If not, see <https://www.gnu.org/licenses/>.

(import scheme
        (chicken base)
        (chicken condition)
        (chicken file)
        (chicken pathname)
        (chicken process)
        (chicken io)
        (chicken repl)
        (chicken process-context)
        (chicken string)
        (chicken time)
        (srfi 1)
        (srfi 13)
        (srfi 18)
        (prefix getopt-long getopt:)
        (prefix nrepl nrepl:)
        (prefix uri-common uri:)
        (prefix vcarded vcard:)
        qt-light)


(define qt-app #f) ;; The <qt-application> object.
(define qt-win #f) ;; The <qt-window> object.


;; Start & run the application.
(define (init)
  (let [(cli-args (parse-cli-args (command-line-arguments)))]
    ;; If --help, then print a usage message and quit.
    (if (alist-ref 'help cli-args)
        (cli-usage))
    ;; Otherwise, let’s get our threads started!
    (let [(qt-thread (init-qt cli-args))
          (nrepl-thread (init-nrepl cli-args))
          (repl-thread (thread-start! repl))]
      ;; Wait for the QT program, even after stdin is closed off.
      (thread-join! qt-thread))))


;; Set up some global variables (for easier live REPL use), prepare the QT app.
(define (init-qt cli-args)
  (set! qt-app (qt:init))
  (set! qt-win (create-window))
  (init-window qt-win)
  ;; Kick off the QT thread, then open the cli free-arg vCard file, if provided.
  ;; That is, like `$ contact freeArgFile.vcf`.
  (let [(qt-thread (thread-start! qt-loop))
        (last-free-arg (condition-case (last (car cli-args)) (var () #f)))]
    (if (and last-free-arg (string? last-free-arg) (file-exists? last-free-arg))
       (open-vcard-file qt-win last-free-arg))
    qt-thread))


;; Kick off our remote TCP-accessible REPL, if the user enabled it at cli.
(define (init-nrepl cli-args)
  (if (alist-ref 'repl cli-args)
      (thread-start!
       (lambda ()
         (nrepl:nrepl (string->number (alist-ref 'repl cli-args)))))))


;; Print a “usage” help message, telling the user how to run the program.
(define (cli-usage)
  (print "usage: " (pathname-file (program-name)) " [-h] [--repl PORT] [VCF_FILE]")
  (print)
  (print (pathname-file (program-name)) " is a simple contacts program for managing")
  (print "vCard-format contacts.")
  (print)
  (print (getopt:usage cli-args-grammar))
  (exit))


;; Parse out command-line args into an alist.
;;    '("dad" "-h" "--repl=12" "mm") → '(("dad" "mm") (help #t) (repl 12))
(define (parse-cli-args args)
  (handle-exceptions
      exn
      (and
        (print ((condition-property-accessor 'exn 'message) exn))
        '((help . #t)))
    (getopt:getopt-long args cli-args-grammar)))


;; Definition of our command-line arguments, in getopt-long’s format.
(define cli-args-grammar
  '((help "display this help message"
          (single-char #\h))
    (repl "start a TCP-accesible REPL at the given port"
          (value #t))))


;; Loop through QT’s processing, again and again.
(define (qt-loop)
  (qt:run #t)
  (qt-loop))


;; Create the application window.
(define (create-window)
  (qt:widget (window-contents)))


;; Return the UI’s XML, read from “contacts.ui”.
;; We could generate this XML ourselves, and write a nice s-expr front-end,
;; maybe… `o`
(define (window-contents)
  (call-with-input-file
      "contact.ui"
    (lambda (in-port) (read-string #f in-port))))


;; Initialize the window.
(define (init-window window)
  (window-callbacks window)
  (qt:show window))


;; Connect callback functions to widgets’ signals.
(define (window-callbacks window)
  (menubar-callbacks window))


;; Connect callback functions to menubar items.
(define (menubar-callbacks window)
  (let* [(menu-file-exit (qt:find window "actionQuit"))
         (menu-file-save (qt:find window "actionSave"))
         (menu-file-open (qt:find window "actionOpen"))
         (menu-file-new (qt:find window "actionNew"))]
    ;; We connect to https://doc.qt.io/qt-6/qaction.html#triggered
    ;; Simply kill the program.
    (if menu-file-exit
        (qt:connect
         menu-file-exit "triggered()"
         (qt:receiver exit)))
    ;; If they try to Save, tell them it’s not supported.
    (if menu-file-save
        (qt:connect
         menu-file-save "triggered()"
         (qt:receiver
          (lambda ()
            (qt:message "Saving is not implemented.")))))
    ;; If they want a new contact, create a new, blank, window.
    ;; That is, a new process.
    (if menu-file-new
        (qt:connect
         menu-file-new "triggered()"
         (qt:receiver
          (lambda ()
            (let [(program-args
                   ;; If we opened a pre-existing contact (last arg is a file),
                   ;; remove that argument.
                   (drop-right (cdr (argv))
                               (if (file-exists? (last (argv)))
                                   1
                                   0)))]
              (process-run (executable-pathname) program-args))))))
    ;; If they want to open a contact through the Open… dialogue, we should open
    ;; the contact in a new window.
    (if menu-file-open
        (qt:connect
         menu-file-open "triggered()"
         (qt:receiver
          (lambda ()
            (let* [(contacts-dir (conc (get-environment-variable "HOME") "/Contacts"))
                   (selected-file (qt:get-open-filename
                                   "Select a contact file to open…"
                                   contacts-dir))
                   (program-args (append (cdr (argv)) (list selected-file)))]
              (if (not (string-null? selected-file))
                  (process-run
                    (executable-pathname)
                    program-args)))))))))



;; Parse a vCard file and populate the window’s forms with its contents.
(define (open-vcard-file window file)
  (if (and (file-exists? file)
           (file-readable? file))
      (thread-start! (lambda () (populate-with-vcard
                                 window
                                 (with-input-from-file file
                                   vcard:read-vcard))))))


;; Simply map vCard property-names to their corresponding name in the window’s
;; fields.
(define property->formname-alist
  '((FN . "name")
    (ADR . "address")
    (TEL . "homePhone")
    (TEL . "workPhone")
    (EMAIL . "eMail")
    (URL . "url")
    (NICKNAME . "nickname")))


;; Given a parsed vCard in vcarded’s alist format, populate the window’s fields.
;; Here’s the format:
;;    ((PROPERTY (ATTRIBUTES) VALUE)
;;     (FN () "A. Dmytryshyn")
;;     (ADR ("TYPE=home") ("" "" "1234 Abc.", "", "", "", "")))
(define (populate-with-vcard window vcard-alist)
  (map (lambda (property)
         (let* [(formname (alist-ref (car property) property->formname-alist))
                (lineEditName (conc formname "LineEdit"))
                (lineEditWidget (if formname (qt:find window lineEditName) #f))]
           (if lineEditWidget
               (set! (qt:property lineEditWidget "text") (last property)))))
       vcard-alist))


(init)