#!/run/current-system/profile/bin/guile \
-L ./src -e main -s
!#


(use-modules (ice-9 getopt-long)
	     (modules lexer lexer))


(define version "v0.1")


(define (error message)
  (display (string-concatenate `(,message "
Usage:
	gscc [OPTIONS] file
Options:
	--version, -v: print version information
	--debug,   -d: turn on verbose output
	--lex,     -l: run the lexer, but stop before assembly generation
	--parse,   -p: run the lexer and parser, but stop before assembly generation
	--codegen, -c: perform lexing, parsing, and assembly generation, but stop before code emission")))
  (exit #f))

(define (preprocess file)
  "Preprocesses a source file using gcc.
Returns #f on a failure, or the name of the preprocessed
file on a success."
  (let ((preprocessed-file-name (tmpnam)))
    (and
     (zero? (system (string-concatenate `("gcc -E -P " ,file " -o " ,preprocessed-file-name))))
     preprocessed-file-name)))

(define (process file parse? assemble?)
  "Driver for lexing, parsing, and assembly generation."
  (let ((port (open-input-file file)))
    (read-tokens-from-port port)
    (close-input-port port)))

(define (postprocess file dest)
  "Assembles and links file, producing an executable.
Returns #f on a failure, #t on a success."
  (zero? (system (string-concatenate `("gcc " ,file " -o " ,dest)))))

(define (main args)
  (let* ((option-spec
	  '((version (single-char #\v) (value #f))
	    (debug   (single-char #\d) (value #f))
	    (lex     (single-char #\l) (value #f))
	    (parse   (single-char #\p) (value #f))
	    (codegen (single-char #\c) (value #f))))
	 (options (getopt-long args option-spec))
	 (rest (option-ref options '() #f))
	 (file (if (null? rest) #f (car rest))))
    (cond
     ((option-ref options 'version #f)
      (display (string-concatenate `("gscc (the 'Guile Scheme C Compiler', " ,version ")\n"))))
     ((not (equal? 1 (length rest))) (error "Wrong number of arguments."))
     ((or (not file)
	  (not (access? file R_OK))
	  (not (equal? 'regular (stat:type (stat file))))) (error "The file could not be read."))
     (#t
      (let ((source (preprocess file)))
	(when source
	  (display (string-concatenate `("Preprocess reported success (wrote " ,source ").\n")))
	  (process source
		   (not (option-ref options 'lex #f))
		   (not (option-ref options 'parse #f)))))))))


;; Local Variables:
;; mode: scheme
;; End: