;;; geiser-guile.el --- Guile's implementation of the geiser protocols  -*- lexical-binding: t; -*-

;; Copyright (C) 2009-2021 Jose Antonio Ortega Ruiz
;; Start date: Sun Mar 08, 2009 23:03

;; Author: Jose Antonio Ortega Ruiz (jao@gnu.org)
;; Maintainer: Jose Antonio Ortega Ruiz (jao@gnu.org)
;; Keywords: languages, guile, scheme, geiser
;; Homepage: https://gitlab.com/emacs-geiser/guile
;; Package-Requires: ((emacs "25.1") (geiser "0.20"))
;; SPDX-License-Identifier: BSD-3-Clause
;; Version: 0.20

;; This file is NOT part of GNU Emacs.

;;; Commentary:

;; This package extends the `geiser' core package to support GNU
;; Guile.


;;; Code:

(require 'geiser-connection)
(require 'geiser-syntax)
(require 'geiser-custom)
(require 'geiser-repl)
(require 'geiser-impl)
(require 'geiser-base)
(require 'geiser-eval)
(require 'geiser-edit)
(require 'geiser-log)
(require 'geiser)

(require 'compile)
(require 'info-look)

(eval-when-compile (require 'cl-lib))


;;; Customization:

(defgroup geiser-guile nil
  "Customization for Geiser's Guile flavour."
  :group 'geiser)

(geiser-custom--defcustom geiser-guile-binary
    (cond ((eq system-type 'windows-nt) "guile.exe")
          ((eq system-type 'darwin) "guile")
          (t "guile"))
  "Name to use to call the Guile executable when starting a REPL."
  :type '(choice string (repeat string)))

(geiser-custom--defcustom geiser-guile-load-path nil
  "A list of paths to be added to Guile's load path when it's started.
The paths are added to both %`load-path' and %load-compiled path,
and only if they are not already present.  This variable is a
good candidate for an entry in your project's .dir-locals.el."
  :type '(repeat file))

(geiser-custom--defcustom geiser-guile-init-file "~/.guile-geiser"
  "Initialization file with user code for the Guile REPL.
If all you want is to load ~/.guile, set
`geiser-guile-load-init-file-p' instead."
  :type 'string)

(geiser-custom--defcustom geiser-guile-load-init-file-p nil
  "Whether to load ~/.guile when starting Guile.
Note that, due to peculiarities in the way Guile loads its init
file, using `geiser-guile-init-file' is not equivalent to setting
this variable to t."
  :type 'boolean)

(geiser-custom--defcustom geiser-guile-use-declarative-modules-p nil
  "Whether Guile should use \"declarative\" modules limiting mutability.
When set to `t', Guile will enforce immutable bindings in
exported modules."
  :type 'boolean
  :link '(info-link "(guile) Declarative Modules"))

(geiser-custom--defcustom geiser-guile-debug-show-bt-p t
  "Whether to automatically show a full backtrace when entering the debugger.
If nil, only the last frame is shown."
  :type 'boolean)

(geiser-custom--defcustom geiser-guile-show-debug-help-p t
  "Whether to show brief help in the echo area when entering the debugger."
  :type 'boolean)

(geiser-custom--defcustom geiser-guile-warning-level 'medium
  "Verbosity of the warnings reported by Guile.

You can either choose one of the predefined warning sets, or
provide a list of symbols identifying the ones you want.  Possible
choices are arity-mismatch, unbound-variable, unused-variable and
unused-toplevel.  Unrecognised symbols are ignored.

The predefined levels are:

  - Medium: arity-mismatch, unbound-variable, format
  - High: arity-mismatch, unbound-variable, unused-variable, format
  - None: no warnings

Changes to the value of this variable will automatically take
effect on new REPLs.  For existing ones, use the command
\\[geiser-guile-update-warning-level]."
  :type '(choice (const :tag "Medium (arity and unbound vars)" medium)
                 (const :tag "High (also unused vars)" high)
                 (const :tag "No warnings" none)
                 (repeat :tag "Custom" symbol)))

(geiser-custom--defcustom geiser-guile-extra-keywords nil
  "Extra keywords highlighted in Guile scheme buffers."
  :type '(repeat string))

(geiser-custom--defcustom geiser-guile-case-sensitive-p t
  "Non-nil means keyword highlighting is case-sensitive."
  :type 'boolean)

(geiser-custom--defcustom geiser-guile-manual-lookup-other-window-p nil
  "Non-nil means pop up the Info buffer in another window."
  :type 'boolean)

(geiser-custom--defcustom geiser-guile-manual-lookup-nodes
    '("Guile" "guile-2.0")
  "List of info nodes that, when present, are used for manual lookups."
  :type '(repeat string))


;;; REPL support:

(defun geiser-guile--binary ()
  "Return the name of the Guile binary to execute."
  (if (listp geiser-guile-binary)
      (car geiser-guile-binary)
    geiser-guile-binary))

(defvar geiser-guile-scheme-dir
  (expand-file-name "src" (file-name-directory load-file-name))
  "Directory where the Guile scheme geiser modules are installed.")

(defvar geiser-guile--conn-address nil)

(defun geiser-guile--get-connection-address (&optional new)
  "The path to the UNIX socket to talk to Guile in a connection."
  (when new
    (setq geiser-guile--conn-address (make-temp-name "/tmp/geiser-guile-")))
  geiser-guile--conn-address)

(defun geiser-guile--parameters ()
  "Return a list with all parameters needed to start Guile.
This function uses `geiser-guile-init-file' if it exists."
  (let ((init-file (and (stringp geiser-guile-init-file)
                        (expand-file-name geiser-guile-init-file)))
        (q-flags (and (not geiser-guile-load-init-file-p) '("-q")))
        (cflag (format "--listen=%s" (geiser-guile--get-connection-address t))))
    `(,@(and (listp geiser-guile-binary) (cdr geiser-guile-binary))
      ,@q-flags "-L" ,geiser-guile-scheme-dir ,cflag
      ,@(apply 'append (mapcar (lambda (p) (list "-L" p))
                               geiser-guile-load-path))
      ,@(and init-file (file-readable-p init-file) (list "-l" init-file)))))

(defconst geiser-guile--prompt-regexp "^[^@(\n]+@([^)]*)> ")
(defconst geiser-guile--debugger-prompt-regexp
  "^[^@(\n]+@([^)]*?) \\[\\([0-9]+\\)\\]> ")

(defconst geiser-guile--clean-rx
  (format "\\(%s\\)\\|\\(^\\$[0-9]+ = [^\n]+$\\)\\|%s"
          (geiser-con--combined-prompt geiser-guile--prompt-regexp
                                       geiser-guile--debugger-prompt-regexp)
          "\\(\nEntering a new prompt.  Type `,bt' for [^\n]+\\.$\\)"))


;;; Evaluation support:
(defsubst geiser-guile--linearize-args (args)
  "Concatenate the list ARGS."
  (mapconcat 'identity args " "))

(defun geiser-guile--geiser-procedure (proc &rest args)
  "Transform PROC in string for a scheme procedure using ARGS."
  (cl-case proc
    ((eval compile) (format ",geiser-eval %s %s%s"
                            (or (car args) "#f")
                            (geiser-guile--linearize-args (cdr args))
                            (if (cddr args) "" " ()")))
    ((load-file compile-file) (format ",geiser-load-file %s" (car args)))
    ((no-values) ",geiser-no-values")
    ((debug) (concat "," (geiser-guile--linearize-args args) "\n\"\""))
    (t (format "ge:%s (%s)" proc (geiser-guile--linearize-args args)))))

(defun geiser-guile--clean-up-output (str)
  (let ((msg (when (string-match geiser-guile--debugger-prompt-regexp str)
               (format "\n[Debugging level: %s]" (match-string 1 str)))))
    (concat (replace-regexp-in-string geiser-guile--clean-rx "" str) msg)))

(defconst geiser-guile--module-re
  "(define-module +\\(([^)]+)\\)")

(defconst geiser-guile--library-re
  "(library +\\(([^)]+)\\)")

(defun geiser-guile--get-module (&optional module)
  "Find current buffer's module using MODULE as a hint."
  (cond ((null module)
         (save-excursion
           (geiser-syntax--pop-to-top)
           (if (or (re-search-backward geiser-guile--module-re nil t)
                   (re-search-backward geiser-guile--library-re nil t)
                   (re-search-forward geiser-guile--module-re nil t)
                   (re-search-forward geiser-guile--library-re nil t))
               (geiser-guile--get-module (match-string-no-properties 1))
             :f)))
        ((listp module) module)
        ((stringp module)
         (condition-case nil
             (car (geiser-syntax--read-from-string module))
           (error :f)))
        (t :f)))

(defun geiser-guile--module-cmd (module fmt &optional def)
  "Use FMT to format a change to MODULE, with default DEF."
  (when module
    (let* ((module (geiser-guile--get-module module))
           (module (cond ((or (null module) (eq module :f)) def)
                         (t (format "%s" module)))))
      (and module (format fmt module)))))

(defun geiser-guile--import-command (module)
  "Format a REPL command to use MODULE."
  (geiser-guile--module-cmd module ",use %s"))

(defun geiser-guile--enter-command (module)
  "Format a REPL command to enter MODULE."
  (geiser-guile--module-cmd module ",m %s" "(guile-user)"))


(defun geiser-guile--exit-command ()
  "Format a REPL command to quit."
  ",q")

(defun geiser-guile--symbol-begin (module)
  "Find beginning of symbol in the context of MODULE."
  (if module
      (max (save-excursion (beginning-of-line) (point))
           (save-excursion (skip-syntax-backward "^(>") (1- (point))))
    (save-excursion (skip-syntax-backward "^'-()>") (point))))


;;; Compilation shell regexps

(defconst geiser-guile--path-rx "^In \\([^:\n ]+\\):\n")

(defconst geiser-guile--rel-path-rx "^In +\\([^/\n: ]+\\):\n")

(defvar geiser-guile--file-cache (make-hash-table :test 'equal)
  "Internal cache.")

(defun geiser-guile--find-file (file)
  (or (gethash file geiser-guile--file-cache)
      (with-current-buffer (or geiser-debug--sender-buffer (current-buffer))
        (when-let (r geiser-repl--repl)
          (with-current-buffer r
            (geiser-eval--send/result `(:eval (:ge find-file ,file))))))))

(defun geiser-guile--resolve-file (file)
  "Find the given FILE, if it's indeed a file."
  (when (and (stringp file)
             (not (member file
                          '("socket" "stdin" "unknown file" "current input"))))
    (message "Resolving %s" file)
    (cond ((file-name-absolute-p file) file)
          (t (when-let (f (geiser-guile--find-file file))
               (puthash file f geiser-guile--file-cache))))))

(defun geiser-guile--resolve-file-x ()
  "Check if last match contain a resolvable file."
  (let ((f (geiser-guile--resolve-file (match-string-no-properties 1))))
    (and (stringp f) (list f))))


;;; Error display

(defun geiser-guile--set-up-error-links ()
  (setq-local compilation-error-regexp-alist
              `((,geiser-guile--path-rx geiser-guile--resolve-file-x)
                ("^  +\\([0-9]+\\):\\([0-9]+\\)" nil 1 2)
                ("^\\(/.*\\):\\([0-9]+\\):\\([0-9]+\\)" 1 2 3)))
  (font-lock-add-keywords nil
                          `((,geiser-guile--path-rx 1 compilation-error-face))))

(defun geiser-guile--enter-debugger ()
  "Tell Geiser to interact with the debugger."
  (when geiser-guile-show-debug-help-p
    (message "Debugger active. Press , for commands."))
  nil)

(defun geiser-guile--display-error (_module key msg)
  "Display error with given KEY and message MSG."
  (when (stringp msg)
    (geiser-guile--set-up-error-links)
    (save-excursion (insert msg)))
  (not (zerop (length msg))))


;;; Trying to ascertain whether a buffer is Guile Scheme:

(defconst geiser-guile--guess-re
  (format "\\(%s\\|#! *.+\\(/\\| \\)guile\\( *\\\\\\)?\\)"
          geiser-guile--module-re))

(defun geiser-guile--guess ()
  "Ascertain whether we are in a Guile file."
  (save-excursion
    (goto-char (point-min))
    (re-search-forward geiser-guile--guess-re nil t)))


;;; Keywords and syntax

(defconst geiser-guile--builtin-keywords
  '("call-with-input-file"
    "call-with-input-string"
    "call-with-output-file"
    "call-with-output-string"
    "call-with-prompt"
    "call-with-trace"
    "define-accessor"
    "define-class"
    "define-enumeration"
    "define-inlinable"
    "define-syntax-parameter"
    "eval-when"
    "lambda*"
    "syntax-parameterize"
    "use-modules"
    "with-error-to-file"
    "with-error-to-port"
    "with-error-to-string"
    "with-fluid*"
    "with-fluids"
    "with-fluids*"
    "with-input-from-port"
    "with-input-from-string"
    "with-output-to-port"
    "with-output-to-string"))

(defun geiser-guile--keywords ()
  "Return Guile-specific scheme keywords."
  (append
   (geiser-syntax--simple-keywords geiser-guile-extra-keywords)
   (geiser-syntax--simple-keywords geiser-guile--builtin-keywords)
   `((,(rx "(" (group "define-once") eow (* space) (? (group (+ word))))
      (1 font-lock-keyword-face)
      (2 font-lock-variable-name-face nil t))
     ("(\\(define-module\\) +(\\([^)]+\\))"
      (1 font-lock-keyword-face)
      (2 font-lock-type-face nil t)))))

(geiser-syntax--scheme-indent
 (c-declare 0)
 (c-lambda 2)
 (call-with-input-string 1)
 (call-with-output-string 0)
 (call-with-prompt 1)
 (call-with-trace 0)
 (eval-when 1)
 (lambda* 1)
 (pmatch defun)
 (sigaction 1)
 (syntax-parameterize 1)
 (with-error-to-file 1)
 (with-error-to-port 1)
 (with-error-to-string 0)
 (with-fluid* 1)
 (with-fluids 1)
 (with-fluids* 1)
 (with-input-from-string 1)
 (with-method 1)
 (with-mutex 1)
 (with-output-to-string 0)
 (with-throw-handler 1))


;;; REPL startup

(defconst geiser-guile-minimum-version "2.2")

(defun geiser-guile--version (binary)
  "Find Guile's version running BINARY."
  (car (process-lines binary "-c" "(display (version))")))

(defun geiser-guile-update-warning-level ()
  "Update the warning level used by the REPL.
The new level is set using the value of `geiser-guile-warning-level'."
  (interactive)
  (let ((code `(:eval (:ge set-warnings ',geiser-guile-warning-level)
                      (geiser evaluation))))
    (geiser-eval--send/result code)))

;;;###autoload
(defun connect-to-guile ()
  "Start a Guile REPL connected to a remote process.

Start the external Guile process with the flag --listen to make
it spawn a server thread."
  (interactive)
  (geiser-connect 'guile))

(defun geiser-guile--set-geiser-load-path ()
  "Set up scheme load path for REPL."
  (let* ((path geiser-guile-scheme-dir)
         (witness "geiser/emacs.scm")
         (code `(begin (if (not (%search-load-path ,witness))
                           (set! %load-path (cons ,path %load-path)))
                       'done)))
    (geiser-eval--send/wait code)))

(defun geiser-guile--set-up-declarative-modules ()
  "Set up Guile to (not) use declarative modules.
See `geiser-guile-use-declarative-modules-p'."
  (unless geiser-guile-use-declarative-modules-p
    (let ((code '(begin (eval-when (expand) (user-modules-declarative? :f)) 'ok)))
      (geiser-eval--send/wait code))))

(defun geiser-guile--startup (remote)
  "Startup function, for a remote connection if REMOTE is t."
  (geiser-guile--set-up-error-links)
  (let ((geiser-log-verbose-p t)
        (g-load-path (buffer-local-value 'geiser-guile-load-path
                                         (or geiser-repl--last-scm-buffer
                                             (current-buffer)))))
    (when (or geiser-guile--conn-address remote)
      (geiser-guile--set-geiser-load-path))
    (geiser-guile--set-up-declarative-modules)
    (geiser-eval--send/wait ",use (geiser emacs)\n'done")
    (dolist (dir g-load-path)
      (let ((dir (expand-file-name dir)))
        (geiser-eval--send/wait `(:eval (:ge add-to-load-path ,dir)))))
    (geiser-guile-update-warning-level)))


;;; Manual lookup

(defun geiser-guile--info-spec (&optional nodes)
  "Return info specification for given NODES."
  (let* ((nrx "^[       ]+-+ [^:]+:[    ]*")
         (drx "\\b")
         (res (when (Info-find-file "r5rs" t)
                `(("(r5rs)Index" nil ,nrx ,drx)))))
    (dolist (node (or nodes geiser-guile-manual-lookup-nodes) res)
      (when (Info-find-file node t)
        (mapc (lambda (idx)
                (add-to-list 'res
                             (list (format "(%s)%s" node idx) nil nrx drx)))
              '("Variable Index" "Procedure Index" "R5RS Index"))))))


(info-lookup-add-help :topic 'symbol :mode 'geiser-guile-mode
                      :ignore-case nil
                      :regexp "[^()`',\"        \n]+"
                      :doc-spec (geiser-guile--info-spec))

(defun geiser-guile--manual-look-up (id _mod)
  "Look for ID in the Guile manuals."
  (let ((info-lookup-other-window-flag
         geiser-guile-manual-lookup-other-window-p))
    (info-lookup-symbol (symbol-name id) 'geiser-guile-mode))
  (when geiser-guile-manual-lookup-other-window-p
    (switch-to-buffer-other-window "*info*"))
  (search-forward (format "%s" id) nil t))


;;; Implementation definition:

(define-geiser-implementation guile
  (binary geiser-guile--binary)
  (arglist geiser-guile--parameters)
  (version-command geiser-guile--version)
  (minimum-version geiser-guile-minimum-version)
  (repl-startup geiser-guile--startup)
  (connection-address geiser-guile--get-connection-address)
  (prompt-regexp geiser-guile--prompt-regexp)
  (clean-up-output geiser-guile--clean-up-output)
  (debugger-prompt-regexp geiser-guile--debugger-prompt-regexp)
  (enter-debugger geiser-guile--enter-debugger)
  (marshall-procedure geiser-guile--geiser-procedure)
  (find-module geiser-guile--get-module)
  (enter-command geiser-guile--enter-command)
  (exit-command geiser-guile--exit-command)
  (import-command geiser-guile--import-command)
  (find-symbol-begin geiser-guile--symbol-begin)
  (display-error geiser-guile--display-error)
  (external-help geiser-guile--manual-look-up)
  (check-buffer geiser-guile--guess)
  (keywords geiser-guile--keywords)
  (case-sensitive geiser-guile-case-sensitive-p))

;;;###autoload
(geiser-activate-implementation 'guile)

;;;###autoload
(autoload 'run-guile "geiser-guile" "Start a Geiser Guile REPL." t)

;;;###autoload
(autoload 'switch-to-guile "geiser-guile"
  "Start a Geiser Guile REPL, or switch to a running one." t)

(provide 'geiser-guile)
;;; geiser-guile.el ends here