(defun my/cleanup-buffer-safe ()
  "Perform a bunch of safe operations on the whitespace content of a buffer.
Does not indent buffer, because it is used for a before-save-hook, and that
might be bad."
  (interactive)
  (if (not (or (string= major-mode 'makefile-gmake-mode)
               (string= major-mode 'makefile-mode)))
      (untabify (point-min) (point-max)))
  (delete-trailing-whitespace)
  (set-buffer-file-coding-system 'utf-8))

(defun my/cleanup-buffer ()
  "Perform a bunch of operations on the whitespace content of a buffer.
Including indent-buffer, which should not be called automatically on save."
  (interactive)
  (my/cleanup-buffer-safe)
  (indent-region (point-min) (point-max)))

(global-set-key (kbd "C-c n") 'my/cleanup-buffer)

(defun my/rotate-windows ()
  "Rotate your windows"
  (interactive)
  (cond ((not (> (count-windows)1))
         (message "You can't rotate a single window!"))
        (t
         (setq i 1)
         (setq numWindows (count-windows))
         (while  (< i numWindows)
           (let* (
                  (w1 (elt (window-list) i))
                  (w2 (elt (window-list) (+ (% i numWindows) 1)))

                  (b1 (window-buffer w1))
                  (b2 (window-buffer w2))

                  (s1 (window-start w1))
                  (s2 (window-start w2))
                  )
             (set-window-buffer w1  b2)
             (set-window-buffer w2 b1)
             (set-window-start w1 s2)
             (set-window-start w2 s1)
             (setq i (1+ i)))))))
(global-set-key (kbd "C-x w r") 'my/rotate-windows)

(defun my/toggle-window-split ()
  (interactive)
  (if (= (count-windows) 2)
      (let* ((this-win-buffer (window-buffer))
             (next-win-buffer (window-buffer (next-window)))
             (this-win-edges (window-edges (selected-window)))
             (next-win-edges (window-edges (next-window)))
             (this-win-2nd (not (and (<= (car this-win-edges)
                                         (car next-win-edges))
                                     (<= (cadr this-win-edges)
                                         (cadr next-win-edges)))))
             (splitter
              (if (= (car this-win-edges)
                     (car (window-edges (next-window))))
                  'split-window-horizontally
                'split-window-vertically)))
        (delete-other-windows)
        (let ((first-win (selected-window)))
          (funcall splitter)
          (if this-win-2nd (other-window 1))
          (set-window-buffer (selected-window) this-win-buffer)
          (set-window-buffer (next-window) next-win-buffer)
          (select-window first-win)
          (if this-win-2nd (other-window 1))))))
(global-set-key (kbd "C-x w t") 'my/rotate-windows)
