;;; flycheck-android-experimental.el --- Flycheck for Android using experimental
;;;                                      gradle plugin

;; Copyright (C) 2017 by Joel Klinghed

;; Author: Joel Klinghed <the_jk@yahoo.com>

;;; Commentary:

;;; Code:

(require 'flycheck)

(defvar flycheck-android-sessiondir nil
  "Session directory used for caching.")

(flycheck-def-option-var flycheck-android-java-checkstyle-jar nil android-java
  "Path to checkstyle-VERSION-all.jar."
  :safe #'stringp)
(make-variable-buffer-local 'flycheck-android-java-checkstyle-jar)

(flycheck-def-option-var flycheck-android-java-checkstyle-path nil android-java
  "Path to use as workdir and base for config and properties."
  :safe #'stringp)
(make-variable-buffer-local 'flycheck-android-java-checkstyle-path)

(flycheck-def-option-var flycheck-android-java-checkstyle-config nil android-java
  "Path to checkstyle-config.xml if one should be used."
  :safe #'stringp)
(make-variable-buffer-local 'flycheck-android-java-checkstyle-config)

(flycheck-def-option-var flycheck-android-java-checkstyle-properties nil android-java
  "Path to checkstyle.properties if one should be used."
  :safe #'stringp)
(make-variable-buffer-local 'flycheck-android-java-checkstyle-properties)

(flycheck-define-checker android-java
  "Java syntax checker using javac."
  :command ("python"
            (eval (flycheck-android-find-tool "java"))
            (option "--checkstyle-jar="
                    flycheck-android-java-checkstyle-jar concat)
            (option "--checkstyle-path="
                    flycheck-android-java-checkstyle-path concat)
            (option "--checkstyle-config="
                    flycheck-android-java-checkstyle-config concat)
            (option "--checkstyle-properties="
                    flycheck-android-java-checkstyle-properties concat)
            (eval (flycheck-android-get-sessiondir))
            (eval buffer-file-name)
            source)
  :error-patterns
  ((warning line-start (file-name) ":" line ": warning:"
            (message (one-or-more (not (any "^")))
                     (any "^"))
            line-end)
   (error line-start (file-name) ":" line ": error:"
          (message (one-or-more (not (any "^")))
                   (any "^"))
          line-end)
   ;; checkstyle messages
   (warning line-start (file-name) ":" line ": warning: " (message) line-end)
   (error line-start (file-name) ":" line ":" column ": " (message) line-end)
   (error line-start (file-name) ":" line ": " (message) line-end))
  :modes java-mode)

(defun flycheck-android-find-tool (tool)
  "Find flycheck-android-TOOL.py.
TOOL=name of tool"
  (let ((filename (concat "flycheck-android-" tool ".py")))
    (expand-file-name
     filename
     (concat (file-name-directory (symbol-file 'flycheck-android-find-tool))
             (file-name-as-directory "bin")))))

(defun flycheck-android-remove-sessiondir ()
  "Delete session dir if it exists and unsets the variable."
  (when flycheck-android-sessiondir
    (delete-directory flycheck-android-sessiondir t)
    (setq flycheck-android-sessiondir nil)))

(defun flycheck-android-get-sessiondir ()
  "Return sessiondir if already set otherwise create and set it."
  (or flycheck-android-sessiondir
      (progn
        (add-hook 'kill-emacs-hook 'flycheck-android-remove-sessiondir)
        (setq flycheck-android-sessiondir
              (make-temp-file "flycheck-android" t)))))

(add-to-list 'flycheck-checkers 'android-java)

(provide 'flycheck-android-experimental)

;;; flycheck-android-experimental.el ends here