(defun mc/cursor-end (cursor)
  (if (overlay-get cursor 'mark-active)
      (max (overlay-get cursor 'point)
           (overlay-get cursor 'mark))
    (overlay-get cursor 'point)))

(defun mc/cursor-beg (cursor)
  (if (overlay-get cursor 'mark-active)
      (min (overlay-get cursor 'point)
           (overlay-get cursor 'mark))
    (overlay-get cursor 'point)))

(defun mc/furthest-region-end ()
  (let ((end (max (mark) (point))))
    (mc/for-each-fake-cursor
     (setq end (max end (mc/cursor-end cursor))))
    end))

(defun mc/first-region-start ()
  (let ((beg (min (mark) (point))))
    (mc/for-each-fake-cursor
     (setq beg (min beg (mc/cursor-beg cursor))))
    beg))

(defun mc/furthest-cursor-before-point ()
  (let ((beg (min (mark) (point)))
        furthest)
    (mc/for-each-fake-cursor
     (when (< (mc/cursor-beg cursor) beg)
       (setq beg (mc/cursor-beg cursor))
       (setq furthest cursor)))
    furthest))

(defun mc/furthest-cursor-after-point ()
  (let ((end (max (mark) (point)))
        furthest)
    (mc/for-each-fake-cursor
     (when (> (mc/cursor-end cursor) end)
       (setq end (mc/cursor-end cursor))
       (setq furthest cursor)))
    furthest))

(defun mc/region-strings ()
  (let ((strings (list (buffer-substring-no-properties (point) (mark)))))
    (mc/for-each-fake-cursor
     (add-to-list 'strings (buffer-substring-no-properties
                            (mc/cursor-beg cursor)
                            (mc/cursor-end cursor))))
    strings))

;;;###autoload
(defun mc/mark-next-like-this (arg)
  "Find and mark the next part of the buffer matching the currently active region
With negative ARG, delete the last one instead.
With zero ARG, skip the last one and mark next."
  (interactive "p")
  (unless (region-active-p)
    (error "Mark a region to match first."))
  (when (< arg 0)
    (mc/remove-fake-cursor (mc/furthest-cursor-after-point)))
  (when (>= arg 0)
    (let ((case-fold-search nil)
          (point-first (< (point) (mark)))
          (re (regexp-opt (mc/region-strings)))
          (furthest-cursor (mc/furthest-cursor-after-point)))
      (mc/save-excursion
       (goto-char (mc/furthest-region-end))
       (when (= arg 0)
         (mc/remove-fake-cursor furthest-cursor))
       (if (search-forward-regexp re nil t)
           (progn
             (push-mark (match-beginning 0))
             (when point-first (exchange-point-and-mark))
             (mc/create-fake-cursor-at-point))
         (error "no more found forward")))))
  (if (> (mc/num-cursors) 1)
      (multiple-cursors-mode 1)
    (multiple-cursors-mode 0)))

;;;###autoload
(defun mc/mark-previous-like-this (arg)
  "Find and mark the previous part of the buffer matching the currently active region
With negative ARG, delete the last one instead.
With zero ARG, skip the last one and mark next."
  (interactive "p")
  (unless (region-active-p)
    (error "Mark a region to match first."))
  (when (< arg 0)
    (mc/remove-fake-cursor (mc/furthest-cursor-before-point)))
  (when (>= arg 0)
    (let ((case-fold-search nil)
          (point-first (< (point) (mark)))
          (re (regexp-opt (mc/region-strings)))
          (furthest-cursor (mc/furthest-cursor-before-point)))
      (mc/save-excursion
       (goto-char (mc/first-region-start))
       (when (= arg 0)
         (mc/remove-fake-cursor furthest-cursor))
       (if (search-backward-regexp re nil t)
           (progn
             (push-mark (match-end 0))
             (unless point-first (exchange-point-and-mark))
             (mc/create-fake-cursor-at-point))
         (error "no more found backward")))))
  (if (> (mc/num-cursors) 1)
      (multiple-cursors-mode 1)
    (multiple-cursors-mode 0)))

(provide 'mc-mark-more)