;;; test-pearl-mention.el --- Tests for @-mentioning Linear users -*- 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 user @-mention picker: the candidate builder, the insert
;; command (`pearl-mention-user'), the compose-buffer self-inserting `@'
;; trigger, and the keymap binding.

;;; Code:

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

(defun test-pearl-mention--members ()
  "Member node alists as `pearl--team-collection' returns them."
  '(((id . "u1") (name . "Eric Bell") (displayName . "eric") (email . "e@x"))
    ((id . "u2") (name . "vrezh.mikayelyan@deepsat.com")
     (displayName . "vrezh.mikayelyan") (email . "v@x"))
    ((id . "u3") (name . "Bot") (displayName . nil) (email . "b@x"))))

;;; --mention-candidates

(ert-deftest test-pearl-mention-candidates-maps-to-handle ()
  "Each member maps a display string to its `@displayName' token; the display
carries the full name so you can find a teammate without recalling the handle."
  (let ((cands (pearl--mention-candidates (test-pearl-mention--members))))
    (should (equal "@eric" (cdr (assoc "Eric Bell (@eric)" cands))))
    (should (equal "@vrezh.mikayelyan"
                   (cdr (assoc "vrezh.mikayelyan@deepsat.com (@vrezh.mikayelyan)" cands))))))

(ert-deftest test-pearl-mention-candidates-drops-handleless ()
  "A member with no displayName has no mention handle and is dropped."
  (let ((cands (pearl--mention-candidates (test-pearl-mention--members))))
    (should-not (cl-find "@" (mapcar #'cdr cands)
                         :test (lambda (_ v) (string-match-p "Bot" (or v "")))))
    (should (= 2 (length cands)))))

;;; pearl-mention-user (insert at point)

(ert-deftest test-pearl-mention-user-inserts-handle-at-point ()
  "With a team in context, the command inserts the chosen `@displayName'."
  (cl-letf (((symbol-function 'pearl--team-collection)
             (lambda (_kind _team &optional _force) (test-pearl-mention--members)))
            ((symbol-function 'completing-read)
             (lambda (&rest _) "Eric Bell (@eric)")))
    (with-temp-buffer
      (insert "*** TODO Title\n:PROPERTIES:\n:LINEAR-ID: a\n:LINEAR-TEAM-ID: t1\n:END:\nPing ")
      (org-mode)
      (goto-char (point-max))
      (pearl-mention-user)
      (should (string-suffix-p "Ping @eric" (buffer-substring (line-beginning-position) (point)))))))

(ert-deftest test-pearl-mention-user-no-team-errors ()
  "Outside any team context (no compose team, no issue heading) it errors."
  (with-temp-buffer
    (insert "plain text, no Linear heading")
    (org-mode)
    (goto-char (point-max))
    (should-error (pearl-mention-user) :type 'user-error)))

;;; keymap

(ert-deftest test-pearl-mention-bound-under-prefix ()
  "C-; L @ resolves to the mention command."
  (should (eq 'pearl-mention-user (lookup-key pearl-prefix-map "@"))))

;;; compose-buffer self-inserting @

(ert-deftest test-pearl-compose-at-self-insert-picks-at-boundary ()
  "At a token boundary the `@' trigger pops the picker and inserts the handle."
  (cl-letf (((symbol-function 'pearl--read-mention) (lambda (_team) "@eric")))
    (with-temp-buffer
      (setq-local pearl--compose-team-id "t1")
      (insert "Ping ")               ; point preceded by a space = boundary
      (pearl--compose-at-self-insert)
      (should (string= "Ping @eric" (buffer-string))))))

(ert-deftest test-pearl-compose-at-self-insert-literal-mid-token ()
  "Mid-token (e.g. inside an email) `@' inserts a literal at-sign, no picker."
  (cl-letf (((symbol-function 'pearl--read-mention)
             (lambda (_team) (error "picker should not run mid-token"))))
    (with-temp-buffer
      (setq-local pearl--compose-team-id "t1")
      (insert "foo")                 ; point after a word char = not a boundary
      (pearl--compose-at-self-insert)
      (should (string= "foo@" (buffer-string))))))

(ert-deftest test-pearl-compose-at-self-insert-cancel-leaves-literal ()
  "Cancelling the picker (quit) leaves a literal `@' rather than aborting input."
  (cl-letf (((symbol-function 'pearl--read-mention)
             (lambda (_team) (signal 'quit nil))))
    (with-temp-buffer
      (setq-local pearl--compose-team-id "t1")
      (insert "Ping ")
      (pearl--compose-at-self-insert)
      (should (string= "Ping @" (buffer-string))))))

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