#!/bin/sh
# -*- scheme -*-
exec guile $GUILE_FLAGS -e '(@@ (guile-tools) main)' -s "$0" "$@"
!#

;;;; guile-tools --- running scripts bundled with Guile
;;;; Andy Wingo <wingo@pobox.com> --- April 2009
;;;; 
;;;; 	Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc.
;;;; 
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;; 
;;;; This library 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
;;;; Lesser General Public License for more details.
;;;; 
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free
;;;; Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;;;; Boston, MA 02110-1301 USA

(define-module (guile-tools)
  #:use-module ((srfi srfi-1) #:select (fold append-map))
  #:autoload (ice-9 format) (format))

;; Hack to provide scripts with the bug-report address.
(module-define! the-scm-module
                '%guile-bug-report-address
                "@PACKAGE_BUGREPORT@")


(define *option-grammar*
  '((help (single-char #\h))
    (version (single-char #\v))))

(define (display-help)
  (display "\
Usage: guile-tools --version
       guile-tools --help
       guile-tools PROGRAM [ARGS]

If PROGRAM is \"list\" or omitted, display available scripts, otherwise
PROGRAM is run with ARGS.
"))

(define (display-version)
  (format #t "guile-tools (GNU Guile ~A) ~A
Copyright (C) 2010 Free Software Foundation, Inc.
License LGPLv3+: GNU LGPL version 3 or later <http://gnu.org/licenses/lgpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
" (version) (effective-version)))

(define (directory-files dir)
  (if (and (file-exists? dir) (file-is-directory? dir))
      (let ((dir-stream (opendir dir)))
        (let loop ((new (readdir dir-stream))
                   (acc '()))
          (if (eof-object? new)
              (begin
                (closedir dir-stream)
                acc)
              (loop (readdir dir-stream)
                    (if (or (string=? "."  new)             ; ignore
                            (string=? ".." new))            ; ignore
                        acc
                        (cons new acc))))))
      '()))

(define (strip-extensions path)
  (or-map (lambda (ext)
            (and
             (string-suffix? ext path)
             (substring path 0
                        (- (string-length path) (string-length ext)))))
          (append %load-compiled-extensions %load-extensions)))

(define (unique l)
  (cond ((null? l) l)
        ((null? (cdr l)) l)
        ((equal? (car l) (cadr l)) (unique (cdr l)))
        (else (cons (car l) (unique (cdr l))))))

(define (find-submodules head)
  (let ((shead (map symbol->string head)))
    (unique
     (sort
      (append-map (lambda (path)
                    (fold (lambda (x rest)
                            (let ((stripped (strip-extensions x)))
                              (if stripped (cons stripped rest) rest)))
                          '()
                          (directory-files
                           (fold (lambda (x y) (in-vicinity y x)) path shead))))
                  %load-path)
      string<?))))

(define (list-scripts)
  (for-each (lambda (x)
              ;; would be nice to show a summary.
              (format #t "~A\n" x))
            (find-submodules '(scripts))))

(define (find-script s)
  (resolve-module (list 'scripts (string->symbol s)) #:ensure #f))

(define (getopt args grammar)
  (define (fail)
    (format (current-error-port)
            "Try `guile-tools --help' for more information.~%")
    (exit 1))

  (define (unrecognized-arg arg)
    (format (current-error-port)
            "guile-tools: unrecognized option: `~a'~%" arg)
    (fail))

  (define (unexpected-value sym val)
    (format (current-error-port)
            "guile-tools: option `--~a' does not take an argument (given ~s)~%"
            sym val)
    (fail))

  (define (single-char-table grammar)
    (cond
     ((null? grammar) '())
     ((assq 'single-char (cdar grammar))
      => (lambda (form)
           (acons (cadr form) (car grammar)
                  (single-char-table (cdr grammar)))))
     (else
      (single-char-table (cdr grammar)))))
  
  (let ((single (single-char-table grammar)))
    (let lp ((args (cdr args)) (options '()))
      (cond
       ((or (null? args) (equal? (car args) "-"))
        (values (reverse options) args))
       ((equal? (car args) "--")
        (values (reverse options) (cdr args)))
       ((string-prefix? "--" (car args))
        (let* ((str (car args))
               (eq (string-index str #\= 2))
               (sym (string->symbol
                     (substring str 2 (or eq (string-length str)))))
               (val (and eq (substring str (1+ eq))))
               (spec (assq sym grammar)))
          (cond
           ((not spec)
            (unrecognized-arg (substring str 0 (or eq (string-length str)))))
           (val
            ;; no values for now
            (unexpected-value sym val))
           ((assq-ref (cdr spec) 'value)
            (error "options with values not supported right now"))
           (else
            (lp (cdr args) (acons sym #f options))))))
       ((string-prefix? "-" (car args))
        (let lp* ((chars (cdr (string->list (car args)))) (options options))
          (if (null? chars)
              (lp (cdr args) options)
              (let ((spec (assv-ref single (car chars))))
                (cond
                 ((not spec)
                  (unrecognized-arg (string #\- (car chars))))
                 ((assq-ref (cdr spec) 'value)
                  (error "options with values not supported right now"))
                 (else
                  (lp* (cdr chars) (acons (car spec) #f options))))))))
       (else (values (reverse options) args))))))

(define (main args)
  (setlocale LC_ALL "")
  (call-with-values (lambda () (getopt args *option-grammar*))
    (lambda (options args)
      (cond
       ((assq 'help options)
        (display-help)
        (exit 0))
       ((assq 'version options)
        (display-version)
        (exit 0))
       ((or (equal? args '())
            (equal? args '("list")))
        (list-scripts))
       ((find-script (car args))
        => (lambda (mod)
             (exit (apply (module-ref mod 'main) (cdr args)))))
       (else
        (format (current-error-port)
                "guile-tools: unknown script ~s~%" (car args))
        (format (current-error-port)
                "Try `guile-tools --help' for more information.~%")
        (exit 1))))))