(require 'org)

(global-set-key (kbd "<f12>") #'org-agenda)
(global-set-key (kbd "C-c a") #'org-agenda)

(defun bh/is-project-p ()
  "Any task with a todo keyword subtask"
  (save-restriction
    (widen)
    (let ((has-subtask)
          (subtree-end (save-excursion (org-end-of-subtree t)))
          (is-a-task (member (nth 2 (org-heading-components)) org-todo-keywords-1)))
      (save-excursion
        (forward-line 1)
        (while (and (not has-subtask)
                    (< (point) subtree-end)
                    (re-search-forward "^\*+ " subtree-end t))
          (when (member (org-get-todo-state) org-todo-keywords-1)
            (setq has-subtask t))))
      (and is-a-task has-subtask))))

(defun bh/is-project-subtree-p ()
  "Any task with a todo keyword that is in a project subtree.
Callers of this function already widen the buffer view."
  (let ((task (save-excursion (org-back-to-heading 'invisible-ok)
                              (point))))
    (save-excursion
      (bh/find-project-task)
      (if (equal (point) task)
          nil
        t))))

(defun bh/is-task-p ()
  "Any task with a todo keyword and no subtask"
  (save-restriction
    (widen)
    (let ((has-subtask)
          (subtree-end (save-excursion (org-end-of-subtree t)))
          (is-a-task (member (nth 2 (org-heading-components)) org-todo-keywords-1)))
      (save-excursion
        (forward-line 1)
        (while (and (not has-subtask)
                    (< (point) subtree-end)
                    (re-search-forward "^\*+ " subtree-end t))
          (when (member (org-get-todo-state) org-todo-keywords-1)
            (setq has-subtask t))))
      (and is-a-task (not has-subtask)))))

(defun bh/is-subproject-p ()
  "Any task which is a subtask of another project"
  (let ((is-subproject)
        (is-a-task (member (nth 2 (org-heading-components)) org-todo-keywords-1)))
    (save-excursion
      (while (and (not is-subproject) (org-up-heading-safe))
        (when (member (nth 2 (org-heading-components)) org-todo-keywords-1)
          (setq is-subproject t))))
    (and is-a-task is-subproject)))

(defun bh/list-sublevels-for-projects-indented ()
  "Set org-tags-match-list-sublevels so when restricted to a subtree we list all subtasks.
  This is normally used by skipping functions where this variable is already local to the agenda."
  (if (marker-buffer org-agenda-restrict-begin)
      (setq org-tags-match-list-sublevels 'indented)
    (setq org-tags-match-list-sublevels nil))
  nil)

(defun bh/list-sublevels-for-projects ()
  "Set org-tags-match-list-sublevels so when restricted to a subtree we list all subtasks.
  This is normally used by skipping functions where this variable is already local to the agenda."
  (if (marker-buffer org-agenda-restrict-begin)
      (setq org-tags-match-list-sublevels t)
    (setq org-tags-match-list-sublevels nil))
  nil)

(defvar bh/hide-scheduled-and-waiting-next-tasks t)

(defun bh/toggle-next-task-display ()
  (interactive)
  (setq bh/hide-scheduled-and-waiting-next-tasks (not bh/hide-scheduled-and-waiting-next-tasks))
  (when  (equal major-mode 'org-agenda-mode)
    (org-agenda-redo))
  (message "%s WAITING and SCHEDULED NEXT Tasks" (if bh/hide-scheduled-and-waiting-next-tasks "Hide" "Show")))

(defun bh/skip-stuck-projects ()
  "Skip trees that are not stuck projects"
  (save-restriction
    (widen)
    (let ((next-headline (save-excursion (or (outline-next-heading) (point-max)))))
      (if (bh/is-project-p)
          (let* ((subtree-end (save-excursion (org-end-of-subtree t)))
                 (has-next ))
            (save-excursion
              (forward-line 1)
              (while (and (not has-next) (< (point) subtree-end) (re-search-forward "^\\*+ NEXT " subtree-end t))
                (unless (member "WAITING" (org-get-tags-at))
                  (setq has-next t))))
            (if has-next
                nil
              next-headline)) ; a stuck project, has subtasks but no next task
        nil))))

(defun bh/skip-non-stuck-projects ()
  "Skip trees that are not stuck projects"
  ;; (bh/list-sublevels-for-projects-indented)
  (save-restriction
    (widen)
    (let ((next-headline (save-excursion (or (outline-next-heading) (point-max)))))
      (if (bh/is-project-p)
          (let* ((subtree-end (save-excursion (org-end-of-subtree t)))
                 (has-next ))
            (save-excursion
              (forward-line 1)
              (while (and (not has-next) (< (point) subtree-end) (re-search-forward "^\\*+ NEXT " subtree-end t))
                (unless (member "WAITING" (org-get-tags-at))
                  (setq has-next t))))
            (if has-next
                next-headline
              nil)) ; a stuck project, has subtasks but no next task
        next-headline))))

(defun bh/skip-non-projects ()
  "Skip trees that are not projects"
  ;; (bh/list-sublevels-for-projects-indented)
  (if (save-excursion (bh/skip-non-stuck-projects))
      (save-restriction
        (widen)
        (let ((subtree-end (save-excursion (org-end-of-subtree t))))
          (cond
           ((bh/is-project-p)
            nil)
           ((and (bh/is-project-subtree-p) (not (bh/is-task-p)))
            nil)
           (t
            subtree-end))))
    (save-excursion (org-end-of-subtree t))))

(defun bh/skip-non-tasks ()
  "Show non-project tasks.
Skip project and sub-project tasks, habits, and project related tasks."
  (save-restriction
    (widen)
    (let ((next-headline (save-excursion (or (outline-next-heading) (point-max)))))
      (cond
       ((bh/is-task-p)
        nil)
       (t
        next-headline)))))

(defun bh/skip-project-trees-and-habits ()
  "Skip trees that are projects"
  (save-restriction
    (widen)
    (let ((subtree-end (save-excursion (org-end-of-subtree t))))
      (cond
       ((bh/is-project-p)
        subtree-end)
       ((org-is-habit-p)
        subtree-end)
       (t
        nil)))))

(defun bh/skip-projects-and-habits-and-single-tasks ()
  "Skip trees that are projects, tasks that are habits, single non-project tasks"
  (save-restriction
    (widen)
    (let ((next-headline (save-excursion (or (outline-next-heading) (point-max)))))
      (cond
       ((org-is-habit-p)
        next-headline)
       ((and bh/hide-scheduled-and-waiting-next-tasks
             (member "WAITING" (org-get-tags-at)))
        next-headline)
       ((bh/is-project-p)
        next-headline)
       ((and (bh/is-task-p) (not (bh/is-project-subtree-p)))
        next-headline)
       (t
        nil)))))

(defun bh/skip-project-tasks-maybe ()
  "Show tasks related to the current restriction.
When restricted to a project, skip project and sub project tasks, habits, NEXT tasks, and loose tasks.
When not restricted, skip project and sub-project tasks, habits, and project related tasks."
  (save-restriction
    (widen)
    (let* ((subtree-end (save-excursion (org-end-of-subtree t)))
           (next-headline (save-excursion (or (outline-next-heading) (point-max))))
           (limit-to-project (marker-buffer org-agenda-restrict-begin)))
      (cond
       ((bh/is-project-p)
        next-headline)
       ((org-is-habit-p)
        subtree-end)
       ((and (not limit-to-project)
             (bh/is-project-subtree-p))
        subtree-end)
       ((and limit-to-project
             (bh/is-project-subtree-p)
             (member (org-get-todo-state) (list "NEXT")))
        subtree-end)
       (t
        nil)))))

(defun bh/skip-project-tasks ()
  "Show non-project tasks.
Skip project and sub-project tasks, habits, and project related tasks."
  (save-restriction
    (widen)
    (let* ((subtree-end (save-excursion (org-end-of-subtree t))))
      (cond
       ((bh/is-project-p)
        subtree-end)
       ((org-is-habit-p)
        subtree-end)
       ((bh/is-project-subtree-p)
        subtree-end)
       ((not (org-entry-is-todo-p))
        subtree-end)
       (t
        nil)))))

(defun bh/skip-non-project-tasks ()
  "Show project tasks.
Skip project and sub-project tasks, habits, and loose non-project tasks."
  (save-restriction
    (widen)
    (let* ((subtree-end (save-excursion (org-end-of-subtree t)))
           (next-headline (save-excursion (or (outline-next-heading) (point-max)))))
      (cond
       ((bh/is-project-p)
        next-headline)
       ((org-is-habit-p)
        subtree-end)
       ((and (bh/is-project-subtree-p)
             (member (org-get-todo-state) (list "NEXT")))
        subtree-end)
       ((not (bh/is-project-subtree-p))
        subtree-end)
       (t
        nil)))))

(defun bh/skip-projects-and-habits ()
  "Skip trees that are projects and tasks that are habits"
  (save-restriction
    (widen)
    (let ((subtree-end (save-excursion (org-end-of-subtree t))))
      (cond
       ((bh/is-project-p)
        subtree-end)
       ((org-is-habit-p)
        subtree-end)
       (t
        nil)))))

(defun bh/skip-non-subprojects ()
  "Skip trees that are not projects"
  (let ((next-headline (save-excursion (outline-next-heading))))
    (if (bh/is-subproject-p)
        nil
      next-headline)))

;; CLOCKING ;;
;; Resume clocking task when emacs is restarted
(org-clock-persistence-insinuate)
;;
;; Show lot of clocking history so it's easy to pick items off the C-F11 list
(setq org-clock-history-length 23)
;; Resume clocking task on clock-in if the clock is open
(setq org-clock-in-resume t)
;; Change tasks to NEXT when clocking in
(setq org-clock-in-switch-to-state 'bh/clock-in-to-next)
;; Separate drawers for clocking and logs
(setq org-drawers (quote ("PROPERTIES" "LOGBOOK")))
;; Save clock data and state changes and notes in the LOGBOOK drawer
(setq org-clock-into-drawer t)
;; Sometimes I change tasks I'm clocking quickly - this removes clocked tasks with 0:00 duration
(setq org-clock-out-remove-zero-time-clocks t)
;; Clock out when moving task to a done state
(setq org-clock-out-when-done t)
;; Save the running clock and all clock history when exiting Emacs, load it on startup
(setq org-clock-persist t)
;; Do not prompt to resume an active clock
(setq org-clock-persist-query-resume nil)
;; Enable auto clock resolution for finding open clocks
(setq org-clock-auto-clock-resolution (quote when-no-clock-is-running))
;; Include current clocking task in clock reports
(setq org-clock-report-include-clocking-task t)


(setq bh/keep-clock-running nil)

(defun bh/clock-in-to-next (kw)
  "Switch a task from TODO to NEXT when clocking in.
Skips capture tasks, projects, and subprojects.
Switch projects and subprojects from NEXT back to TODO"
  (when (not (and (boundp 'org-capture-mode) org-capture-mode))
    (cond
     ((and (member (org-get-todo-state) (list "TODO"))
           (bh/is-task-p))
      "NEXT")
     ((and (member (org-get-todo-state) (list "NEXT"))
           (bh/is-project-p))
      "TODO"))))

(defun bh/find-project-task ()
  "Move point to the parent (project) task if any"
  (save-restriction
    (widen)
    (let ((parent-task (save-excursion (org-back-to-heading 'invisible-ok) (point))))
      (while (org-up-heading-safe)
        (when (member (nth 2 (org-heading-components)) org-todo-keywords-1)
          (setq parent-task (point))))
      (goto-char parent-task)
      parent-task)))

(defun bh/punch-in (arg)
  "Start continuous clocking and set the default task to the
selected task.  If no task is selected set the Organization task
as the default task."
  (interactive "p")
  (setq bh/keep-clock-running t)
  (if (equal major-mode 'org-agenda-mode)
      ;;
      ;; We're in the agenda
      ;;
      (let* ((marker (org-get-at-bol 'org-hd-marker))
             (tags (org-with-point-at marker (org-get-tags-at))))
        (if (and (eq arg 4) tags)
            (org-agenda-clock-in '(16))
          (bh/clock-in-organization-task-as-default)))
    ;;
    ;; We are not in the agenda
    ;;
    (save-restriction
      (widen)
      ; Find the tags on the current task
      (if (and (equal major-mode 'org-mode) (not (org-before-first-heading-p)) (eq arg 4))
          (org-clock-in '(16))
        (bh/clock-in-organization-task-as-default)))))

(defun bh/punch-out ()
  (interactive)
  (setq bh/keep-clock-running nil)
  (when (org-clock-is-active)
    (org-clock-out))
  (org-agenda-remove-restriction-lock))

(defun bh/clock-in-default-task ()
  (save-excursion
    (org-with-point-at org-clock-default-task
      (org-clock-in))))

(defun bh/clock-in-parent-task ()
  "Move point to the parent (project) task if any and clock in"
  (let ((parent-task))
    (save-excursion
      (save-restriction
        (widen)
        (while (and (not parent-task) (org-up-heading-safe))
          (when (member (nth 2 (org-heading-components)) org-todo-keywords-1)
            (setq parent-task (point))))
        (if parent-task
            (org-with-point-at parent-task
              (org-clock-in))
          (when bh/keep-clock-running
            (bh/clock-in-default-task)))))))

(defvar bh/organization-task-id "eb155a82-92b2-4f25-a3c6-0304591af2f9")

;; https://stackoverflow.com/a/10091330
(defun zin/org-agenda-skip-tag (tag &optional others)
  "Skip all entries that correspond to TAG.

If OTHERS is true, skip all entries that do not correspond to TAG."
  (let ((next-headline (save-excursion (or (outline-next-heading) (point-max))))
        (current-headline (or (and (org-at-heading-p)
                                   (point))
                              (save-excursion (org-back-to-heading)))))
    (if others
        (if (not (member tag (org-get-tags-at current-headline)))
            next-headline
          nil)
      (if (member tag (org-get-tags-at current-headline))
          next-headline
        nil))))

(defun bh/clock-in-organization-task-as-default ()
  (interactive)
  (org-with-point-at (org-id-find bh/organization-task-id 'marker)
    (org-clock-in '(16))))

(defun bh/clock-out-maybe ()
  (when (and bh/keep-clock-running
             (not org-clock-clocking-in)
             (marker-buffer org-clock-default-task)
             (not org-clock-resolving-clocks-due-to-idleness))
    (bh/clock-in-parent-task)))

(add-hook 'org-clock-out-hook 'bh/clock-out-maybe 'append)

;; AGENDA VIEW ;;

;; Do not dim blocked tasks
(setq org-agenda-compact-blocks nil)
(setq org-agenda-dim-blocked-tasks nil)
(setq org-agenda-block-separator 61)

;; Agenda log mode items to display (closed and state changes by default)
(setq org-agenda-log-mode-items (quote (closed state)))

; For tag searches ignore tasks with scheduled and deadline dates
(setq org-agenda-tags-todo-honor-ignore-options t)

(setq org-icalendar-include-body nil)
(setq org-icalendar-include-bbdb-anniversaries t)
(setq org-icalendar-include-todo t)
(setq org-icalendar-use-scheduled '(todo-start event-if-not-todo event-if-todo-not-done))

(provide 'rul-org-agenda)