#!/bin/sh
# aside from this initial boilerplate, this is actually -*- scheme -*- code
main='(module-ref (resolve-module '\''(scripts use2dot)) '\'main')'
exec ${GUILE-guile} -l $0 -c "(apply $main (cdr (command-line)))" "$@"
!#
;;; use2dot --- Display module dependencies as a DOT specification

;; 	Copyright (C) 2001 Free Software Foundation, Inc.
;;
;; 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 2, 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 software; see the file COPYING.  If not, write to
;; the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
;; Boston, MA 02111-1307 USA

;;; Author: Thien-Thi Nguyen

;;; Commentary:

;; Usage: use2dot [OPTIONS] [FILE ...]
;; Display to stdout a DOT specification that describes module dependencies
;; in FILEs.
;;
;; A top-level `use-modules' form or a `:use-module' `define-module'-component
;; results in a "solid" style edge.
;;
;; An `:autoload' `define-module'-component results in a "dotted" style edge
;; with label "N" indicating that N names are responsible for triggering the
;; autoload.
;;
;; A top-level `load' or `primitive-load' form results in a a "bold" style
;; edge to a node named with either the file name if the `load' argument is a
;; string, or "[computed in FILE]" otherwise.
;;
;; Options:
;; --default-module MOD  -- Set MOD as the default module (for top-level
;;                          `use-modules' forms that do not follow some
;;                          `define-module' form in a file).  MOD should be
;;                          be a list or `#f', in which case such top-level
;;                          `use-modules' forms are effectively ignored.
;;                          Default value: `(guile)'.
;;
;; TODO
;; - add `--load-synonyms' option
;; - add `--ignore-module' option
;; - handle arbitrary command-line key/value configuration

;;; Code:

(define-module (scripts use2dot)
  :use-module (ice-9 regex))

(define (string-append/separator separator strings)
  ;; from (ttn stringutils) -- todo: use srfi-13
  ;;   "Append w/ SEPARATOR a list of STRINGS.
  ;; SEPARATOR can be a character or a string."
  (let ((rev (reverse strings))
        (sep (if (char? separator)
                 (make-string 1 separator)
                 separator)))
    (apply string-append
           (let loop ((s (cdr rev))
                      (acc (list (car rev))))
             (if (null? s)
                 acc
                 (loop (cdr s)
                       (cons (car s)
                             (cons sep acc))))))))

(define (mapconcat proc ls sep)
  ;; from (ttn stringutils) -- todo: use srfi-13
  ;; "Map PROC over LS, concatening resulting strings with separator SEP."
  (string-append/separator sep (map proc ls)))

(define default-module '(guile))

(define (q s)                           ; quote
  (format #f "~S" s))

(define (vv pair)                       ; var=val
  (format #f "~A=~A" (car pair) (cdr pair)))

(define (spew module use . etc)
  (and module
       (let ((etc-spec (if (null? etc)
                           ""
                           (format #f " [~A]" (mapconcat vv etc ",")))))
         (format #t "  \"~A\" -> \"~A\"~A;\n" module use etc-spec))))

(define (header)
  (format #t "digraph use2dot {")
  (for-each (lambda (s) (format #t "  ~A;\n" s))
            (map vv `((label . ,(q "Guile Module Dependencies"))
                      ;(rankdir . LR)
                      ;(size . ,(q "7.5,10"))
                      (ratio . fill)
                      ;(nodesep . ,(q "0.05"))
                      ))))

(define (grok filename)
  (let* ((p (open-file filename "r"))
         (next (lambda () (read p)))
         (curmod #f))
    (let loop ((form (next)))
      (cond ((eof-object? form))
            ((not (list? form)) (loop (next)))
            (else (case (car form)
                    ((define-module)
                     (let ((module (cadr form)))
                       (set! curmod module)
                       (let loop ((ls form))
                         (or (null? ls)
                             (case (car ls)
                               ((:use-module)
                                (spew module (cadr ls))
                                (loop (cddr ls)))
                               ((:autoload)
                                (spew module (cadr ls)
                                      '(style . dotted)
                                      '(fontsize . 5)
                                      (let ((len (length (caddr ls))))
                                        `(label . ,(q (number->string len)))))
                                (loop (cdddr ls)))
                               (else (loop (cdr ls))))))))
                    ((use-modules)
                     (for-each (lambda (use)
                                 (spew (or curmod default-module) use))
                               (cdr form)))
                    ((load primitive-load)
                     (spew (or curmod default-module)
                           (let ((file (cadr form)))
                             (if (string? file)
                                 file
                                 (format #f "[computed in ~A]" filename)))
                           '(style . bold))))
                  (loop (next)))))))

(define (body files)
  (for-each grok files))

(define (footer)
  (format #t "}"))

(define (use2dot . args)
  (header)
  (let* ((override (cond ((member "--default-module" args) => cadr)
                         (else #f)))
         (files (if override (cddr args) args)))
    (and override
         (set! default-module
               (with-input-from-string override (lambda () (read)))))
    (body files))
  (footer))

(define main use2dot)

;;; use2dot ends here