eclim-problems.el

;;; eclim-problems.el --- an interface to the Eclipse IDE.  -*- lexical-binding: t -*-
;;
;; Copyright (C) 2009, 2012  Tassilo Horn <tassilo@member.fsf.org>
;;
;; 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 3 of the License, 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 program.  If not, see <http://www.gnu.org/licenses/>.
;;
;;; Contributors
;;
;;  - Nikolaj Schumacher <bugs * nschum de>
;;  - Yves Senn <yves senn * gmx ch>
;;  - Fredrik Appelberg <fredrik * bitbakery se>
;;  - Alessandro Arzilli <alessandro.arzilli * gmail com>
;;
;;; Commentary:
;;
;;
;;; Code:

(require 'popup)
(require 'hl-line)
(require 'cl-lib)
(require 'eclim-common)
(eval-when-compile (require 'eclim-macros))

(defgroup eclim-problems nil
  "Settings for displaying problems in code and the problems buffer."
  :group 'eclim)

(defface eclim-problems-highlight-error-face
  '((t (:underline "red")))
  "Face used for highlighting errors in code."
  :group 'eclim-problems)

(defface eclim-problems-highlight-warning-face
  '((t (:underline "orange")))
  "Face used for highlighting warnings in code."
  :group 'eclim-problems)

(defvar eclim-problems-mode-hook nil
  "Hook run after entering `eclim-problems-mode'.")

(defvar eclim-problems-mode-map
      (let ((map (make-keymap)))
        (suppress-keymap map t)
        (define-key map (kbd "a") 'eclim-problems-show-all)
        (define-key map (kbd "e") 'eclim-problems-show-errors)
        (define-key map (kbd "g") 'eclim-problems-buffer-refresh)
        (define-key map (kbd "q") 'eclim-quit-window)
        (define-key map (kbd "w") 'eclim-problems-show-warnings)
        (define-key map (kbd "f") 'eclim-problems-toggle-filefilter)
        (define-key map (kbd "c") 'eclim-problems-correct)
        (define-key map (kbd "RET") 'eclim-problems-open-current)
        map)
  "The local key map to use in `eclim-problems-mode'.")

(define-key eclim-mode-map (kbd "C-c C-e b") 'eclim-problems)
(define-key eclim-mode-map (kbd "C-c C-e o") 'eclim-problems-open)

(defconst eclim--problems-buffer-name "*eclim: problems*"
  "The name to use for the problems buffer.")

(defconst eclim--problems-compilation-buffer-name "*compilation: eclim*"
  "The name to use for the compilation buffer.")

(defun eclim--problems-mode ()
  "Activate `eclim-problems-mode' on the current buffer.

This is not a real major mode, though it behaves like one.
In particular, note that the activated mode is
`eclim-problems-mode', but there is no major mode by that
name."
  (kill-all-local-variables)
  (buffer-disable-undo)
  (setq major-mode 'eclim-problems-mode
        mode-name "eclim/problems"
        mode-line-process ""
        truncate-lines t
        buffer-read-only t
        default-directory (eclim/workspace-dir))
  (setq-local line-move-visual nil)
  (setq mode-line-format
        (list "-"
              'mode-line-mule-info
              'mode-line-modified
              'mode-line-frame-identification
              'mode-line-buffer-identification

              "   "
              'mode-line-position

              "  "
              'eclim--problems-filter-description

              "  "
              'mode-line-modes
              '(which-func-mode ("" which-func-format "--"))

              'global-mode-string
              "-%-"))
  (hl-line-mode t)
  (use-local-map eclim-problems-mode-map)
  (run-mode-hooks 'eclim-problems-mode-hook))

(defun eclim--problems-apply-filter (f)
  "Set the problems filter to F.
If F is nil, all problems will be reported.  A value of \"e\"
means that only errors are reported.  A value of \"w\" means
that only warnings are reported."
  (setq eclim--problems-filter f)
  (eclim-problems-buffer-refresh))

(defun eclim-problems-show-errors ()
  "Set the problems filter to only report errors."
  (interactive)
  (eclim--problems-apply-filter "e"))

(defun eclim-problems-toggle-filefilter ()
  "Toggle whether to only report problems for the current file."
  (interactive)
  (setq eclim--problems-filefilter (not eclim--problems-filefilter))
  (eclim--problems-buffer-redisplay))

(defun eclim-problems-show-warnings ()
  "Set the problems filter to only report warnings."
  (interactive)
  (eclim--problems-apply-filter "w"))

(defun eclim-problems-show-all ()
  "Set the problems filter to show both errors and warnings."
  (interactive)
  (eclim--problems-apply-filter nil))

(defadvice find-file (after eclim-problems-highlight-on-find-file activate)
  "Highlight problems in a source buffer once it is opened."
  (eclim-problems-highlight))

(defadvice find-file-other-window (after eclim-problems-highlight-on-find-file-other-window activate)
  "Highlight problems in a source buffer once it is opened."
  (eclim-problems-highlight))

(defadvice other-window (after eclim-problems-highlight-on-other-window activate)
  "Highlight problems in a source buffer when switching windows."
  (eclim-problems-highlight))

(defadvice switch-to-buffer (after eclim-problems-highlight-switch-to-buffer activate)
  "Highlight problems in a source buffer when switching buffers."
  (eclim-problems-highlight))

(defun eclim--problems-get-current-problem ()
  "Return the problem at the current position.

If the problems buffer is the current buffer, return the
problem on the current line.  Otherwise, return the problem
corresponding to the current source position.  An error is
raised if no problem corresponds to the current position."
  (let ((buf (eclim--get-problems-buffer)))
    (if (eq buf (current-buffer))
        ;; we are in the problems buffer
        (let ((problems (eclim--problems-filtered))
              (index (1- (line-number-at-pos))))
          (if (>= index (length problems))
              (error "No problem on this line.")
            (aref problems index)))
      ;; we need to figure out which problem corresponds to this pos
      (save-restriction
        (widen)
        (let ((line (line-number-at-pos)))
          (or (cl-find-if (lambda (p) (and (string= (assoc-default 'filename p) (file-truename buffer-file-name))
                                           (= (assoc-default 'line p) line)))
                          eclim--problems-list)
              (error "No problem on this line")))))))

(defun eclim-problems-open-current (&optional same-window)
  "Jump to the file and location of the current problem.
If SAME-WINDOW is provided and non-nil, the file will be
opened in the current window.  Otherwise, it is opened in
another window."
  (interactive)
  (let* ((p (eclim--problems-get-current-problem)))
    (funcall (if same-window
                 'find-file
               'find-file-other-window)
             (assoc-default 'filename p))
    (eclim--problem-goto-pos p)))

(defun eclim-problems-correct ()
  "Show a suggestion for the current correction.
This can be invoked in either the problems buffer or a
source code buffer."
  (interactive)
  (let ((p (eclim--problems-get-current-problem)))
    (unless (string-match "\\.\\(groovy\\|java\\)$" (cdr (assoc 'filename p)))
      (error "Not a Java or Groovy file.  Corrections are currently supported only for Java or Groovy"))
    (if (eq major-mode 'eclim-problems-mode)
        (let ((p-buffer (find-file-other-window (assoc-default 'filename p))))
          (with-selected-window (get-buffer-window p-buffer t)
            ;; Intentionally DON'T save excursion. Often times we need edits.
            (eclim--problem-goto-pos p)
            (eclim-java-correct (cdr (assoc 'line p)) (eclim--byte-offset))))
      ;; source code buffer
      (eclim-java-correct (cdr (assoc 'line p)) (eclim--byte-offset)))))

(defun eclim--warning-filterp (x)
  "Return non-nil if the problem X is a warning."
  (eq t (assoc-default 'warning x)))

(defun eclim--error-filterp (x)
  "Return non-nil if the problem X is an error."
  (not (eclim--warning-filterp x)))

(defun eclim--get-problems-buffer ()
  "Return the existing problems buffer, or nil of none exists."
  (get-buffer eclim--problems-buffer-name))

(defun eclim--get-problems-buffer-create ()
  "Return the eclim problems buffer, creating one if none exists."
  (or (eclim--get-problems-buffer)
      (progn
        (eclim--problems-mode-init t)
        (eclim--get-problems-buffer))))

(defun eclim--problems-mode-init (&optional quiet)
  "Create and initialize the eclim problems buffer.
If the optional argument QUIET is non-nil, open the buffer
in the background without switching to it."
  (let ((buf (get-buffer-create eclim--problems-buffer-name)))
    (save-excursion
      (setq eclim--problems-project (eclim-project-name))
      (setq eclim--problems-file buffer-file-name)
      (set-buffer buf)
      (eclim--problems-mode)
      (eclim-problems-buffer-refresh)
      (goto-char (point-min)))
    (if (not quiet)
        (switch-to-buffer buf))))

(defun eclim-problems ()
  "Switch to and refresh the problems buffer.
If the problems buffer does not exist yet, it is created."
  (interactive)
  (if (eclim-project-name)
      (eclim--problems-mode-init)
    (error "Could not figure out the current project. Is this an eclim managed buffer?")))

(defun eclim-problems-open ()
  "Switch to the problems buffer in a new Emacs window.
The new window will be in the current frame.  The problems
buffer will be updated to show that latest compilation
problems."
  (interactive)
  (let ((w (selected-window)))
    (select-window (split-window nil (round (* (window-height w) 0.75)) nil))
    (eclim-problems)
    (select-window w)))

(add-hook 'find-file-hook
          (lambda () (when (eclim--accepted-p (buffer-file-name))
                       ;; Ensure the problems buffer exists.
                       (eclim--get-problems-buffer-create))))

(defun eclim-problems-refocus ()
  "Change the project and source file for the problems buffer."
  (interactive)
  (when (eclim--project-dir)
    (setq eclim--problems-project (eclim-project-name))
    (setq eclim--problems-file buffer-file-name)
    (with-current-buffer eclim--problems-buffer-name
      (eclim-problems-buffer-refresh))))

(defun eclim-problems-next (&optional same-window)
  "Jump to the location of the next problem.
If SAME-WINDOW is provided and non-nil, the location of the
problem is opened in the current window.  Otherwise, it is
opened in another window."
  (interactive)
  (let ((prob-buf (get-buffer eclim--problems-buffer-name)))
    (when prob-buf
      (set-buffer prob-buf)
      (if (boundp 'eclim--problems-list-at-first)
          (setq eclim--problems-list-at-first nil)
        (forward-line 1))
      (hl-line-move hl-line-overlay)
      (eclim-problems-open-current same-window))))

(defun eclim-problems-previous (&optional same-window)
  "Jump to the location of the previous problem.
If SAME-WINDOW is provided and non-nil, the location of the
problem is opened in the current window.  Otherwise, it is
opened in another window."
  (interactive)
  (let ((prob-buf (get-buffer eclim--problems-buffer-name)))
    (when prob-buf
      (set-buffer prob-buf)
      (forward-line -1)
      (hl-line-move hl-line-overlay)
      (eclim-problems-open-current same-window))))

(defun eclim-problems-next-same-window ()
  "In the current window, jump to the next problem.
See `eclim-problems-next'."
  (interactive)
  (eclim-problems-next t))

(defun eclim-problems-previous-same-window ()
  "In the current window, jump to the previous problem.
See `eclim-problems-previous'."
  (interactive)
  (eclim-problems-previous t))

(defun eclim-problems-compilation-buffer ()
  "Create a compilation buffer from eclim problems.
This is convenient as it lets the user navigate between
errors using `next-error' (\\[next-error])."
  (interactive)
  (let ((filecol-size (eclim--problems-filecol-size))
        (project-directory (concat (eclim--project-dir) "/"))
        (compil-buffer (get-buffer-create eclim--problems-compilation-buffer-name))
        (project-name (eclim-project-name))) ; To store it in buffer.

    (with-current-buffer compil-buffer
      (setq default-directory project-directory)
      (setq mode-line-process
            (concat ": " (propertize "refreshing"
                                     'face 'compilation-mode-line-run))))
    ;; Remember that the part below is asynchronous. This can be tricky.
    (eclim--with-problems-list _problems
      (let (saved-user-pos)
        (with-current-buffer compil-buffer
          (buffer-disable-undo)
          (setq buffer-read-only nil)
          (setq saved-user-pos (point))
          (erase-buffer)
          (let ((errors 0) (warnings 0))
            (cl-loop for problem across (eclim--problems-filtered) do
                     (eclim--insert-problem-compilation
                      problem filecol-size project-directory)
                     (if (eq t (assoc-default 'warning problem)) ; :json-false, WTH
                         (setq warnings (1+ warnings))
                       (setq errors (1+ errors))))
            (let ((msg (format
                        "Compilation results: %d errors, %d warnings [%s].\n"
                        errors warnings (current-time-string))))
              (insert "\n" msg)
              (goto-char (point-min))
              (insert msg "\n"))
            (compilation-mode)
            ;; The above killed local variables
            (setq default-directory project-directory)
            (setq eclim--project-name project-name)
            ;; Remap the very dangerous "g" command :)  A make -k in some of
            ;; my projects would throw Eclipse off-balance by cleaning .classes.
            ;; May look funky, but it's safe.
            (local-set-key "g" 'eclim-problems-compilation-buffer)

            (setq mode-line-process
                  (concat ": "
                          (propertize (format "%d/%d" errors warnings)
                                      'face (when (> errors 0)
                                              'compilation-mode-line-fail))))))
        ;; Sometimes, buffer was already current. Note outside with-current-buf.
        (unless (eq compil-buffer (current-buffer))
          (display-buffer compil-buffer 'other-window))
        (with-selected-window (get-buffer-window compil-buffer t)
          (when (< saved-user-pos (point-max))
            (goto-char saved-user-pos)))))))

(defun eclim--insert-problem-compilation (problem _filecol-size project-directory)
  "Add PROBLEM to the compilation buffer.
_FILECOL-SIZE is the width to make the filename column.  It
is currently not respected, however.
PROJECT-DIRECTORY is the path to the project root directory.
It will be stripped from file names before they are
displayed."
  (let ((filename (cl-first (split-string (assoc-default 'filename problem) project-directory t)))
        (description (assoc-default 'message problem))
        (type (if (eq t (assoc-default 'warning problem)) "W" "E")))
    (let ((line (assoc-default 'line problem))
          (col (assoc-default 'column problem)))
      (insert (format "%s:%s:%s: %s: %s\n" filename line col (upcase type) description)))))

(defun eclim--count-current-errors ()
  "Count the number of problems which are errors."
  (length
   (eclim--filter-problems "e" t (buffer-file-name (current-buffer)) eclim--problems-list)))

(defun eclim--count-current-warnings ()
  "Count the number of problems which are warnings."
  (length
   (eclim--filter-problems "w" t (buffer-file-name (current-buffer)) eclim--problems-list)))

(defun eclim-problems-next-same-file (&optional up)
  "Move to the next problem in the current file, with wraparound.
If UP is provided and non-nil, move to the previous problem
instead.  In an interactive call, UP is the prefix argument.
See `eclim-problems-prev-same-file'."
  (interactive "P")
  ;; This seems pretty inefficient, but it's fast enough. Would be even
  ;; more inefficient if we didn't assume problems were sorted.
  (let ((problems-file
         (eclim--filter-problems nil t (buffer-file-name (current-buffer))
                                 eclim--problems-list))
        (pass-line (line-number-at-pos))
        (pass-col (+ (current-column) (if up 0 1)))
        (first-passed nil) (last-not-passed nil))
    (when (= 0 (length problems-file)) (error "No problems in this file"))
    (cl-loop for p across problems-file until first-passed do
             (let ((line (assoc-default 'line p))
                   (col (assoc-default 'column p)))
               (if (or (> line pass-line)
                       (and (= line pass-line) (> col pass-col)))
                   (setq first-passed p)
                 (setq last-not-passed p))))
    (eclim--problem-goto-pos
     (or
      (if up last-not-passed first-passed)
      (when up (message "Moved past first error, continuing to last")
            (elt problems-file (- (length problems-file) 1))) ; Ugh, vector
      (progn (message "Moved past last error, continuing to first")
             (elt problems-file 0))))))

(defun eclim-problems-prev-same-file ()
  "Move to the previous problem in the current file, with wraparound."
  (interactive)
  (eclim-problems-next-same-file t))


(defun eclim-problems-modeline-string ()
  "Return a modeline string summarizing problems in the current file."
  (concat (format ": %s/%s"
                  (eclim--count-current-errors)
                  (eclim--count-current-warnings))
          (when eclim--problems-refreshing "*")))

(provide 'eclim-problems)
;;; eclim-problems ends here