;;; Find global Lisp definitions
;;; Author: Jerry James
;;;
;;; Copyright (C) 2008 by Jeremiah W. James
;;; FIXME: Choose a license

(defconst directory-sep-string (char-to-string directory-sep-char)
  "The directory separating character, as a one-character string.")

;;; FIXME: More defining forms that we may want to track some day:
;;; defact, defface, defgroup, define-behavior, define-behavior-group,
;;; define-error, define-setf-method, and defsetf.
(defconst analyze-defs-symbols
  (concat
   "^"
   (regexp-opt '("def-gdb-var" "def-gdb-variable" "defalias" "defalias-compat"
		 "defalias-maybe" "defclass" "defconst" "defconst-maybe"
		 "defcustom" "defezimage" "deffoo" "defgeneric" "defimage"
		 "define-compatible-function-alias"
		 "define-compatible-variable-alias" "define-compiler-macro"
		 "define-function" "define-hmac-function"
		 "define-obsolete-function-alias"
		 "define-obsolete-variable-alias" "define-overload"
		 "define-skeleton" "define-structure" "define-victim-slot"
		 "define-victim-slots" "deflocal" "defmacro" "defmacro*"
		 "defmacro-maybe" "defmacro-maybe-cond" "defmath" "defstruct"
		 "defsubst" "defsubst-maybe" "defsubst-maybe-cond" "defun"
		 "defun*" "defun-bbdb-raw-notes-accessor" "defun-compat"
		 "defun-cvs-mode" "defun-maybe" "defun-maybe-cond"
		 "defun-when-void" "defunx" "defvar" "defvar-mabye"
		 "defvaralias" "defvoo" "skk-deflocalvar"
		 "viper-deflocalvar")))
  "Regexp matching definitions to store.")

;;; FIXME: How do we handle defalias and defvaralias: (quote foo)?
;;; WARNING: This function uses the variable "filename" as a special variable.
(defun analyze-defs-extract (form)
  "Extract definition characteristics from a Lisp form.
All definitions in the form are returned in a list.  Each list element is a
3-element vector of the form [NAME TYPE FILENAME], where NAME is the defined
symbol, TYPE is one of the symbols defun, defmacro, defsubst, etc., and
FILENAME is a string giving the absolute pathname of the defining file."
  (when (consp form)
    (let ((type (car form)))
      (when (symbolp type)
	(let ((name (symbol-name type)))
	  (if (string-match analyze-defs-symbols name)
	      (list (vector (cadr form) type filename))
	    (unless (eq type 'quote)
	      (mapcan #'analyze-defs-extract (rest form)))))))))

(defun analyze-defs-file (filename)
  "Find all global definitions in the file named FILENAME.
The definitions are returned in a list with the same structure as that returned
by `analyze-defs-extract'."
  (when (string-match "\\.el$" filename)
    (with-temp-buffer
      (insert-file-contents filename)
      (let ((buf (current-buffer))
	    defs)
	(condition-case nil
	    (while t
	      (setq defs (nconc defs (analyze-defs-extract (read buf)))))
	  (end-of-file defs))))))

(defun analyze-defs-dir (dirname)
  "Find all global definitions in the directory DIRNAME and it subdirectories.
The definitions are returned in a list with the same structure as that returned
by `analyze-defs-extract'."
  (if (file-directory-p dirname)
      (mapcan #'analyze-defs-dir
	      (mapcar #'(lambda (filename)
			  (concat dirname directory-sep-string filename))
		      (delete ".." (delete "." (directory-files dirname)))))
    (analyze-defs-file dirname)))