;;; dockerfile-mode.el --- Major mode for editing Docker's Dockerfiles

;; Copyright (c) 2013 Spotify AB
;;
;; Licensed under the Apache License, Version 2.0 (the "License"); you may not
;; use this file except in compliance with the License. You may obtain a copy of
;; the License at
;;
;; http://www.apache.org/licenses/LICENSE-2.0
;;
;; Unless required by applicable law or agreed to in writing, software
;; distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
;; WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
;; License for the specific language governing permissions and limitations under
;; the License.

;;; Code:

(require 'sh-script)
(require 'rx)

(declare-function cygwin-convert-file-name-to-windows "cygw32.c" (file &optional absolute-p))

(defvar docker-image-name nil)

(defgroup dockerfile nil
  "dockerfile code editing commands for Emacs."
  :link '(custom-group-link :tag "Font Lock Faces group" font-lock-faces)
  :prefix "dockerfile-"
  :group 'languages)

(defcustom dockerfile-mode-hook nil
  "*Hook called by `dockerfile-mode'."
  :type 'hook
  :group 'dockerfile)

(defcustom dockerfile-use-sudo nil
  "Runs docker builder command with sudo.")

(defcustom dockerfile-build-args nil
  "List of --build-arg to pass to docker build.

Each element of the list will be passed as a separate
 --build-arg to the docker build command."
  :type '(repeat string)
  :group 'dockerfile)

(defvar dockerfile-font-lock-keywords
  `(,(cons (rx (or line-start "onbuild ")
               (group (or "from" "maintainer" "run" "cmd" "expose" "env" "arg"
                          "add" "copy" "entrypoint" "volume" "user" "workdir" "onbuild"
                          "label" "stopsignal"))
               word-boundary)
           font-lock-keyword-face)
    ,@(sh-font-lock-keywords)
    ,@(sh-font-lock-keywords-2)
    ,@(sh-font-lock-keywords-1))
  "Default font-lock-keywords for `dockerfile mode'.")

(defvar dockerfile-mode-map
  (let ((map (make-sparse-keymap))
        (menu-map (make-sparse-keymap)))
    (define-key map "\C-c\C-b" 'dockerfile-build-buffer)
    (define-key map "\C-c\M-b" 'dockerfile-build-no-cache-buffer)
    (define-key map "\C-c\C-z" 'dockerfile-test-function)
    (define-key map "\C-c\C-c" 'comment-region)
    (define-key map [menu-bar dockerfile-mode] (cons "Dockerfile" menu-map))
    (define-key menu-map [dfc]
      '(menu-item "Comment Region" comment-region
                  :help "Comment Region"))
    (define-key menu-map [dfb]
      '(menu-item "Build" dockerfile-build-buffer
                  :help "Send the Dockerfile to docker build"))
    (define-key menu-map [dfb]
      '(menu-item "Build without cache" dockerfile-build-no-cache-buffer
                  :help "Send the Dockerfile to docker build without cache"))
    map))

(defvar dockerfile-mode-syntax-table
  (let ((table (make-syntax-table)))
    (modify-syntax-entry ?# "<" table)
    (modify-syntax-entry ?\n ">" table)
    (modify-syntax-entry ?' "\"" table)
    table)
  "Syntax table for `dockerfile-mode'.")

(define-abbrev-table 'dockerfile-mode-abbrev-table nil
  "Abbrev table used while in `dockerfile-mode'.")

(unless dockerfile-mode-abbrev-table
  (define-abbrev-table 'dockerfile-mode-abbrev-table ()))

(defun dockerfile-build-arg-string ()
  "Create a --build-arg string for each element in `dockerfile-build-args'."
  (mapconcat (lambda (arg) (concat "--build-arg " "\"" arg "\""))
             dockerfile-build-args " "))

(defun standard-filename (file)
  "Convert the file name to OS standard.
If in Cygwin environment, uses Cygwin specific function to convert the
file name. Otherwise, uses Emacs' standard conversion function."
  (format "%s" (if (fboundp 'cygwin-convert-file-name-to-windows)
                   (s-replace "\\" "\\\\" (cygwin-convert-file-name-to-windows file))
                 (convert-standard-filename file))))

;;;###autoload
(defun dockerfile-build-buffer (image-name)
  "Build an image based upon the buffer"
  (interactive
   (if (null docker-image-name)
       (list (read-string "image-name: " nil nil))
     (list docker-image-name)))
  (save-buffer)
  (if (stringp image-name)
      (async-shell-command
       (format "%sdocker build -t %s %s -f \"%s\" \"%s\""
               (if dockerfile-use-sudo "sudo " "")
               image-name
               (dockerfile-build-arg-string)
               (standard-filename (buffer-file-name))
               (standard-filename (file-name-directory (buffer-file-name))))
       "*docker-build-output*")
    (print "docker-image-name must be a string, consider surrounding it with double quotes")))

;;;###autoload
(defun dockerfile-build-no-cache-buffer (image-name)
  "Build an image based upon the buffer without cache"
  (interactive
   (if (null docker-image-name)
       (list (read-string "image-name: " nil nil))
     (list docker-image-name)))
  (save-buffer)
  (if (stringp image-name)
      (async-shell-command
       (format "%s docker build --no-cache -t %s %s -f \"%s\" \"%s\""
               (if dockerfile-use-sudo "sudo" "")
               image-name
               (dockerfile-build-arg-string)
               (standard-filename (buffer-file-name))
               (standard-filename (file-name-directory (buffer-file-name))))
       "*docker-build-output*")
    (print "docker-image-name must be a string, consider surrounding it with double quotes")))

;; Handle emacs < 24, which does not have prog-mode
(defalias 'dockerfile-parent-mode
  (if (fboundp 'prog-mode) 'prog-mode 'fundamental-mode))

;;;###autoload
(define-derived-mode dockerfile-mode dockerfile-parent-mode "Dockerfile"
  "A major mode to edit Dockerfiles.
\\{dockerfile-mode-map}
"
  (set-syntax-table dockerfile-mode-syntax-table)
  (set (make-local-variable 'require-final-newline) mode-require-final-newline)
  (set (make-local-variable 'comment-start) "#")
  (set (make-local-variable 'comment-end) "")
  (set (make-local-variable 'comment-start-skip) "#+ *")
  (set (make-local-variable 'parse-sexp-ignore-comments) t)
  (set (make-local-variable 'font-lock-defaults)
       '(dockerfile-font-lock-keywords nil t))
  (setq local-abbrev-table dockerfile-mode-abbrev-table))

;;;###autoload
(add-to-list 'auto-mode-alist '("Dockerfile.*\\'" . dockerfile-mode))

(provide 'dockerfile-mode)

;;; dockerfile-mode.el ends here