;;; test-pearl-sync-hooks.el --- Tests for pearl org sync hooks -*- lexical-binding: t; -*-

;; Copyright (C) 2026 Craig Jennings

;; Author: Craig Jennings <c@cjennings.net>

;; 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/>.

;;; Commentary:

;; Tests for the org sync hook wiring: enable/disable add and remove
;; buffer-local hooks; the after-save hook only fires for linear.org buffers;
;; and per-heading sync degrades gracefully when point is before any heading.

;;; Code:

(require 'test-bootstrap (expand-file-name "test-bootstrap.el"))
(require 'cl-lib)

;;; enable / disable

(ert-deftest test-pearl-enable-org-sync-adds-buffer-local-hooks ()
  "Enabling sync adds both hook functions buffer-locally."
  (with-temp-buffer
    (pearl-enable-org-sync)
    (should (memq 'pearl-org-hook-function after-save-hook))
    (should (memq 'pearl-sync-org-to-linear org-after-todo-state-change-hook))))

(ert-deftest test-pearl-disable-org-sync-removes-hooks ()
  "Disabling sync removes both hook functions."
  (with-temp-buffer
    (pearl-enable-org-sync)
    (pearl-disable-org-sync)
    (should-not (memq 'pearl-org-hook-function after-save-hook))
    (should-not (memq 'pearl-sync-org-to-linear org-after-todo-state-change-hook))))

;;; org-hook-function buffer guard

(ert-deftest test-pearl-org-hook-function-skips-other-buffer ()
  "The after-save hook does nothing in a buffer that isn't the configured file."
  (let ((called nil)
        (pearl-org-file-path "/tmp/linear.org"))
    (cl-letf (((symbol-function 'pearl-sync-org-to-linear) (lambda () (setq called t))))
      (with-temp-buffer
        (setq buffer-file-name "/tmp/scratch.org")
        (pearl-org-hook-function)
        (should-not called)))))

(ert-deftest test-pearl-org-hook-function-syncs-configured-buffer ()
  "The after-save hook syncs when the buffer visits `pearl-org-file-path'."
  (let ((called nil)
        (pearl-org-file-path "/tmp/linear.org"))
    (cl-letf (((symbol-function 'pearl-sync-org-to-linear) (lambda () (setq called t))))
      (with-temp-buffer
        (setq buffer-file-name "/tmp/linear.org")
        (pearl-org-hook-function)
        (should called)))))

(ert-deftest test-pearl-org-hook-function-honors-custom-path ()
  "A non-default `pearl-org-file-path' is what the hook matches on.
Regression: the hook used to hardcode a \"linear.org$\" regex, so a buffer
named linear.org fired even when the configured file was elsewhere, and a
custom-named configured file never fired."
  (let ((called nil)
        (pearl-org-file-path "/tmp/my-linear-issues.org"))
    (cl-letf (((symbol-function 'pearl-sync-org-to-linear) (lambda () (setq called t))))
      ;; A buffer literally named linear.org must NOT fire when the configured
      ;; file is something else.
      (with-temp-buffer
        (setq buffer-file-name "/tmp/linear.org")
        (pearl-org-hook-function)
        (should-not called))
      ;; The configured custom-named file DOES fire.
      (with-temp-buffer
        (setq buffer-file-name "/tmp/my-linear-issues.org")
        (pearl-org-hook-function)
        (should called)))))

(ert-deftest test-pearl-org-hook-function-matches-through-symlink ()
  "A configured path and a visited symlink to the same file match via truename.
The hook resolves both sides with `file-truename', so a symlink to the
configured file still syncs -- this guards the choice of truename over a raw
string compare."
  (let ((real (make-temp-file "linear-real-" nil ".org"))
        (link (make-temp-file "linear-link-" nil ".org"))
        (called nil))
    (unwind-protect
        (progn
          (delete-file link)
          (make-symbolic-link real link)
          (let ((pearl-org-file-path real))
            (cl-letf (((symbol-function 'pearl-sync-org-to-linear)
                       (lambda () (setq called t))))
              (with-temp-buffer
                (setq buffer-file-name link)
                (pearl-org-hook-function)
                (should called)))))
      (when (file-exists-p link) (delete-file link))
      (when (file-exists-p real) (delete-file real)))))

(ert-deftest test-pearl-org-hook-function-nil-path-no-op ()
  "With `pearl-org-file-path' nil, the hook is a no-op and does not error."
  (let ((called nil)
        (pearl-org-file-path nil))
    (cl-letf (((symbol-function 'pearl-sync-org-to-linear) (lambda () (setq called t))))
      (with-temp-buffer
        (setq buffer-file-name "/tmp/linear.org")
        (should (progn (pearl-org-hook-function) t))
        (should-not called)))))

;;; sync-current-heading-to-linear

(ert-deftest test-pearl-sync-current-heading-before-first-heading-no-error ()
  "Syncing with point before the first heading degrades gracefully.

Regression: `org-back-to-heading' signals \"before first heading\" in the
preamble, which must not propagate out of the sync entry point."
  (cl-letf (((symbol-function 'pearl--process-heading-at-point) (lambda () nil)))
    (with-temp-buffer
      (insert "#+TITLE: x\n\npreamble line\n")
      (org-mode)
      (goto-char (point-min))
      (should (progn (pearl-sync-current-heading-to-linear) t)))))

(ert-deftest test-pearl-sync-current-heading-processes-on-heading ()
  "Syncing from within an entry processes that heading."
  (let ((called nil))
    (cl-letf (((symbol-function 'pearl--process-heading-at-point)
               (lambda () (setq called t))))
      (with-temp-buffer
        (insert "* Top\n*** TODO x\n")
        (org-mode)
        (goto-char (point-max))
        (pearl-sync-current-heading-to-linear)
        (should called)))))

;;; sync-org-to-linear dispatcher

(ert-deftest test-pearl-sync-org-to-linear-org-todo-syncs-current-heading ()
  "When invoked from `org-todo', only the current heading is synced."
  (let ((called nil)
        (this-command 'org-todo))
    (cl-letf (((symbol-function 'pearl-sync-current-heading-to-linear)
               (lambda () (setq called t))))
      (pearl-sync-org-to-linear)
      (should called))))

(ert-deftest test-pearl-sync-org-to-linear-otherwise-scans-whole-file ()
  "Outside `org-todo', every matching heading in the buffer is processed."
  (let ((count 0)
        (this-command 'some-other-command)
        (pearl-state-to-todo-mapping '(("Todo" . "TODO") ("Done" . "DONE")))
        (pearl-todo-states-pattern nil)
        (pearl--todo-states-pattern-source nil))
    (cl-letf (((symbol-function 'pearl--process-heading-at-point)
               (lambda () (setq count (1+ count)))))
      (with-temp-buffer
        (insert "*** TODO a\n*** DONE b\n")
        (org-mode)
        (pearl-sync-org-to-linear)
        (should (= 2 count))))))

(provide 'test-pearl-sync-hooks)
;;; test-pearl-sync-hooks.el ends here