;;; org-roam-project-test.el --- ERT tests for org-roam-project -*- lexical-binding: t; -*-

;; Copyright (C) 2026

;; This file is NOT part of GNU Emacs.

;; 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.

;;; Commentary:

;; ERT test suite for org-roam-project.el.
;;
;; Tests use real org-roam (not mocked) to catch compatibility issues.
;; Each test that needs a project creates a temporary git-initialized
;; directory so that project.el's VC backend recognises it.
;;
;; Run from the command line:
;;
;;   make test

;;; Code:

(require 'ert)
(require 'cl-lib)
(require 'org-roam)
(require 'org-roam-project)

;;; ─── Test helpers ────────────────────────────────────────────────────────────

(defun orp-test--make-temp-project ()
  "Create a temporary directory and initialise it as a git repository.
Returns the absolute path to the project root (with trailing slash)."
  (let ((dir (file-name-as-directory
              (make-temp-file "orp-test-project-" t))))
    ;; Git init so project.el recognises it via `project-try-vc'.
    (let ((default-directory dir))
      (call-process "git" nil nil nil "init" "--quiet")
      (call-process "git" nil nil nil "config" "user.email" "test@test.com")
      (call-process "git" nil nil nil "config" "user.name" "Test"))
    dir))

(defun orp-test--cleanup (dir)
  "Recursively delete DIR and remove it from `project--list' if present."
  (when (file-directory-p dir)
    (delete-directory dir t))
  ;; Forget the project so it doesn't pollute other tests.
  ;; Guard against Emacs 30's `unset' sentinel value for project--list.
  (when (and (boundp 'project--list)
             (listp project--list))
    (setq project--list
          (cl-remove-if (lambda (entry)
                          (string-prefix-p dir (car entry)))
                        project--list))))

(defmacro orp-test--with-project (&rest body)
  "Execute BODY inside a fresh temporary git project.
Binds `test-root' (project root with trailing slash) and
`test-notes-dir' (notes subdirectory path, not yet created).
Cleans up unconditionally after BODY."
  (declare (indent 0) (debug t))
  `(let* ((test-root (orp-test--make-temp-project))
          (test-notes-dir (expand-file-name org-roam-project-notes-subdir test-root))
          (default-directory test-root))
     (unwind-protect
         (progn ,@body)
       (orp-test--cleanup test-root))))

(defmacro orp-test--with-initialized-project (&rest body)
  "Execute BODY inside a fresh project whose notes directory already exists.
Also isolates `org-roam-directory' and `org-roam-db-location' so that no
real org-roam database is opened globally."
  (declare (indent 0) (debug t))
  `(orp-test--with-project
     (make-directory test-notes-dir t)
     (let* ((org-roam-directory test-notes-dir)
            (org-roam-db-location
             (expand-file-name org-roam-project-db-filename test-notes-dir)))
       ,@body)))

;;; ─── 1. Customisation defaults ───────────────────────────────────────────────

(ert-deftest orp-test-default-notes-subdir ()
  "Default value of `org-roam-project-notes-subdir' is \"notes\"."
  (should (equal (default-value 'org-roam-project-notes-subdir) "notes")))

(ert-deftest orp-test-default-db-filename ()
  "Default value of `org-roam-project-db-filename' is \".org-roam.db\"."
  (should (equal (default-value 'org-roam-project-db-filename) ".org-roam.db")))

(ert-deftest orp-test-default-auto-create ()
  "Default value of `org-roam-project-auto-create' is nil."
  (should (null (default-value 'org-roam-project-auto-create))))

;;; ─── 2. Safe-local-variable predicates ──────────────────────────────────────

(ert-deftest orp-test-safe-local-notes-subdir ()
  "`org-roam-project-notes-subdir' is safe as a dir-local when it is a string."
  (should (equal (get 'org-roam-project-notes-subdir 'safe-local-variable)
                 #'stringp)))

(ert-deftest orp-test-safe-local-db-filename ()
  "`org-roam-project-db-filename' is safe as a dir-local when it is a string."
  (should (equal (get 'org-roam-project-db-filename 'safe-local-variable)
                 #'stringp)))

;;; ─── 3. org-roam-project--value-in-dir ──────────────────────────────────────

(ert-deftest orp-test-value-in-dir-fallback ()
  "Falls back to the global value when no dir-locals override is present."
  (orp-test--with-project
    ;; No .dir-locals.el exists, so the global default should be returned.
    (let ((org-roam-project-notes-subdir "notes"))
      (should (equal (org-roam-project--value-in-dir
                      'org-roam-project-notes-subdir test-root)
                     "notes")))))

(ert-deftest orp-test-value-in-dir-override ()
  "Returns the dir-local value when .dir-locals.el overrides the variable."
  (orp-test--with-project
    ;; Write a .dir-locals.el that sets the notes subdir to "docs/notes".
    (let ((dir-locals-file (expand-file-name ".dir-locals.el" test-root)))
      (with-temp-file dir-locals-file
        (insert "((nil . ((org-roam-project-notes-subdir . \"docs/notes\"))))"))
      (should (equal (org-roam-project--value-in-dir
                      'org-roam-project-notes-subdir test-root)
                     "docs/notes")))))

;;; ─── 4. org-roam-project--context ───────────────────────────────────────────

(ert-deftest orp-test-context-outside-project ()
  "`org-roam-project--context' returns nil when not inside a project."
  ;; Use the system temp dir which is unlikely to be a project root.
  (let ((default-directory temporary-file-directory))
    (should (null (org-roam-project--context temporary-file-directory)))))

(ert-deftest orp-test-context-no-notes-dir-auto-create-nil ()
  "Returns nil when the notes dir does not exist and auto-create is nil."
  (orp-test--with-project
    (let ((org-roam-project-auto-create nil))
      ;; Notes dir has NOT been created.
      (should (null (org-roam-project--context test-root))))))

(ert-deftest orp-test-context-returns-cons-when-notes-dir-exists ()
  "Returns (notes-dir . db-path) when the notes dir exists."
  (orp-test--with-project
    (make-directory test-notes-dir t)
    (let ((ctx (org-roam-project--context test-root)))
      (should (consp ctx))
      ;; Normalise both sides: the source uses expand-file-name without
      ;; a trailing slash; file-name-as-directory makes comparison robust.
      (should (string= (file-name-as-directory (car ctx))
                       (file-name-as-directory test-notes-dir)))
      (should (string= (cdr ctx)
                       (expand-file-name org-roam-project-db-filename
                                         test-notes-dir))))))

(ert-deftest orp-test-context-auto-create ()
  "Auto-creates the notes dir when `org-roam-project-auto-create' is non-nil."
  (orp-test--with-project
    (let ((org-roam-project-auto-create t))
      ;; Notes dir does not exist yet.
      (should (not (file-directory-p test-notes-dir)))
      (let ((ctx (org-roam-project--context test-root)))
        (should (consp ctx))
        ;; The directory should now have been created.
        (should (file-directory-p test-notes-dir))))))

(ert-deftest orp-test-context-respects-custom-subdir ()
  "Context uses a custom notes subdir."
  (orp-test--with-project
    (let* ((org-roam-project-notes-subdir "custom-notes")
           (custom-notes-dir (expand-file-name "custom-notes" test-root)))
      (make-directory custom-notes-dir t)
      (let ((ctx (org-roam-project--context test-root)))
        (should (consp ctx))
        (should (string-prefix-p custom-notes-dir (car ctx)))))))

(ert-deftest orp-test-context-respects-custom-db-filename ()
  "Context uses a custom database filename."
  (orp-test--with-project
    (let ((org-roam-project-db-filename "my-custom.db"))
      (make-directory test-notes-dir t)
      (let ((ctx (org-roam-project--context test-root)))
        (should (consp ctx))
        (should (string-suffix-p "my-custom.db" (cdr ctx)))))))

;;; ─── 5. org-roam-project--with-context (macro) ──────────────────────────────

(ert-deftest orp-test-with-context-binds-org-roam-vars ()
  "The macro rebinds `org-roam-directory' and `org-roam-db-location'."
  (orp-test--with-initialized-project
    ;; Inside an initialized project the macro should bind to project values.
    (let ((captured-dir nil)
          (captured-db nil))
      (org-roam-project--with-context
        (setq captured-dir org-roam-directory)
        (setq captured-db  org-roam-db-location))
      (should (string= (file-name-as-directory captured-dir)
                       (file-name-as-directory test-notes-dir)))
      (should (string= captured-db
                       (expand-file-name org-roam-project-db-filename
                                         test-notes-dir))))))

(ert-deftest orp-test-with-context-passthrough-outside-project ()
  "The macro uses global values when there is no project context."
  (let* ((global-dir "/tmp/global-notes/")
         (global-db  "/tmp/global-notes/.org-roam.db")
         (org-roam-directory global-dir)
         (org-roam-db-location global-db)
         (default-directory temporary-file-directory)
         (captured-dir nil)
         (captured-db  nil))
    (org-roam-project--with-context
      (setq captured-dir org-roam-directory)
      (setq captured-db  org-roam-db-location))
    (should (string= captured-dir global-dir))
    (should (string= captured-db  global-db))))

;;; ─── 6. org-roam-project--require-context ───────────────────────────────────

(ert-deftest orp-test-require-context-no-project ()
  "Signals `user-error' when not inside a project."
  (let ((default-directory temporary-file-directory))
    (should-error (org-roam-project--require-context)
                  :type 'user-error)))

(ert-deftest orp-test-require-context-no-notes-dir ()
  "Signals `user-error' mentioning `org-roam-project-init' when notes dir absent."
  (orp-test--with-project
    (let ((err (should-error (org-roam-project--require-context)
                             :type 'user-error)))
      (should (string-match-p "org-roam-project-init"
                              (cadr err))))))

(ert-deftest orp-test-require-context-success ()
  "Returns (notes-dir . db-path) when the project is properly initialised."
  (orp-test--with-initialized-project
    (let ((ctx (org-roam-project--require-context)))
      (should (consp ctx))
      (should (string= (file-name-as-directory (car ctx))
                       (file-name-as-directory test-notes-dir)))
      (should (string= (cdr ctx)
                       (expand-file-name org-roam-project-db-filename
                                         test-notes-dir))))))

;;; ─── 7. org-roam-project--add-to-gitignore ──────────────────────────────────

(ert-deftest orp-test-gitignore-no-file ()
  "Does nothing when there is no .gitignore in the project root."
  (orp-test--with-project
    ;; Ensure no .gitignore exists.
    (let ((gitignore (expand-file-name ".gitignore" test-root)))
      (should (not (file-exists-p gitignore)))
      (org-roam-project--add-to-gitignore test-root ".org-roam.db")
      ;; Still should not exist.
      (should (not (file-exists-p gitignore))))))

(ert-deftest orp-test-gitignore-appends-entry ()
  "Appends the db filename as a new line when not already present."
  (orp-test--with-project
    (let ((gitignore (expand-file-name ".gitignore" test-root)))
      (with-temp-file gitignore
        (insert "*.log\n"))
      (org-roam-project--add-to-gitignore test-root ".org-roam.db")
      (let ((contents (with-temp-buffer
                        (insert-file-contents gitignore)
                        (buffer-string))))
        (should (string-match-p "^\.org-roam\.db$" contents))))))

(ert-deftest orp-test-gitignore-no-duplicate ()
  "Does not append the entry when it is already present."
  (orp-test--with-project
    (let ((gitignore (expand-file-name ".gitignore" test-root)))
      (with-temp-file gitignore
        (insert "*.log\n.org-roam.db\n"))
      (org-roam-project--add-to-gitignore test-root ".org-roam.db")
      (let ((contents (with-temp-buffer
                        (insert-file-contents gitignore)
                        (buffer-string))))
        ;; Count occurrences — should be exactly 1.
        (let ((count 0)
              (start 0))
          (while (string-match "\\.org-roam\\.db" contents start)
            (cl-incf count)
            (setq start (match-end 0)))
          (should (= count 1)))))))

(ert-deftest orp-test-gitignore-adds-newline-before-entry ()
  "Ensures a newline is inserted before the entry when the file lacks one."
  (orp-test--with-project
    (let ((gitignore (expand-file-name ".gitignore" test-root)))
      ;; Write file WITHOUT a trailing newline.
      (with-temp-file gitignore
        (insert "*.log"))
      (org-roam-project--add-to-gitignore test-root ".org-roam.db")
      (let ((contents (with-temp-buffer
                        (insert-file-contents gitignore)
                        (buffer-string))))
        ;; The db entry should be on its own line (preceded by \n).
        (should (string-match-p "\n\\.org-roam\\.db\n" contents))))))

;;; ─── 8. org-roam-project--update-file-advice ────────────────────────────────

(ert-deftest orp-test-update-file-advice-with-project ()
  "Advice rebinds org-roam vars when the file belongs to an initialised project."
  (orp-test--with-initialized-project
    (let* ((note-file (expand-file-name "test-note.org" test-notes-dir))
           (seen-dir nil)
           (seen-db  nil)
           (orig-fn  (lambda (&optional _file _no-req)
                       (setq seen-dir org-roam-directory)
                       (setq seen-db  org-roam-db-location))))
      (with-temp-file note-file (insert "* Test\n"))
      (org-roam-project--update-file-advice orig-fn note-file nil)
      (should (string= (file-name-as-directory seen-dir)
                       (file-name-as-directory test-notes-dir)))
      (should (string= seen-db
                       (expand-file-name org-roam-project-db-filename
                                         test-notes-dir))))))

(ert-deftest orp-test-update-file-advice-without-project ()
  "Advice calls orig-fn unchanged when the file is not in any project."
  (let* ((global-dir "/tmp/global-roam/")
         (global-db  "/tmp/global-roam/.org-roam.db")
         (org-roam-directory global-dir)
         (org-roam-db-location global-db)
         (seen-dir nil)
         (seen-db  nil)
         (orig-fn  (lambda (&optional _file _no-req)
                     (setq seen-dir org-roam-directory)
                     (setq seen-db  org-roam-db-location)))
         ;; A file that lives in /tmp and is not in any VC project.
         (lone-file (concat temporary-file-directory "lone-file.org")))
    (org-roam-project--update-file-advice orig-fn lone-file nil)
    (should (string= seen-dir global-dir))
    (should (string= seen-db  global-db))))

;;; ─── 9. project-switch-commands integration ─────────────────────────────────

(defun orp-test--switch-command-present-p (cmd)
  "Return non-nil when CMD appears in `project-switch-commands'."
  (cl-find cmd project-switch-commands :key #'car))

(ert-deftest orp-test-register-adds-commands ()
  "Registering adds both roam-find and capture entries."
  (let ((project-switch-commands (copy-sequence project-switch-commands)))
    (org-roam-project--register-switch-commands)
    (should (orp-test--switch-command-present-p 'org-roam-project-node-find))
    (should (orp-test--switch-command-present-p 'org-roam-project-capture))))

(ert-deftest orp-test-unregister-removes-commands ()
  "Unregistering removes both entries."
  (let ((project-switch-commands (copy-sequence project-switch-commands)))
    (org-roam-project--register-switch-commands)
    (org-roam-project--unregister-switch-commands)
    (should (not (orp-test--switch-command-present-p 'org-roam-project-node-find)))
    (should (not (orp-test--switch-command-present-p 'org-roam-project-capture)))))

(ert-deftest orp-test-register-is-idempotent ()
  "Calling register twice does not produce duplicate entries."
  (let ((project-switch-commands (copy-sequence project-switch-commands)))
    (org-roam-project--register-switch-commands)
    (org-roam-project--register-switch-commands)
    (let ((find-count
           (cl-count 'org-roam-project-node-find project-switch-commands
                     :key #'car))
          (capture-count
           (cl-count 'org-roam-project-capture project-switch-commands
                     :key #'car)))
      (should (= find-count 1))
      (should (= capture-count 1)))))

;;; ─── 10. org-roam-project-mode ──────────────────────────────────────────────

(defmacro orp-test--with-mode-off (&rest body)
  "Execute BODY ensuring `org-roam-project-mode' is disabled beforehand
and restored to its prior state afterward."
  (declare (indent 0) (debug t))
  `(let ((was-on org-roam-project-mode)
         (project-switch-commands (copy-sequence project-switch-commands)))
     (when org-roam-project-mode
       (org-roam-project-mode -1))
     (unwind-protect
         (progn ,@body)
       ;; Restore: ensure mode is off after the test regardless.
       (when org-roam-project-mode
         (org-roam-project-mode -1))
       (when was-on
         (org-roam-project-mode 1)))))

(ert-deftest orp-test-mode-enable-installs-advice ()
  "Enabling the mode installs advice on `org-roam-db-update-file'."
  (orp-test--with-mode-off
    (org-roam-project-mode 1)
    (should (advice-member-p #'org-roam-project--update-file-advice
                              'org-roam-db-update-file))))

(ert-deftest orp-test-mode-disable-removes-advice ()
  "Disabling the mode removes the advice."
  (orp-test--with-mode-off
    (org-roam-project-mode 1)
    (org-roam-project-mode -1)
    (should (not (advice-member-p #'org-roam-project--update-file-advice
                                   'org-roam-db-update-file)))))

(ert-deftest orp-test-mode-enable-registers-switch-commands ()
  "Enabling the mode adds commands to `project-switch-commands'."
  (orp-test--with-mode-off
    (org-roam-project-mode 1)
    (should (orp-test--switch-command-present-p 'org-roam-project-node-find))
    (should (orp-test--switch-command-present-p 'org-roam-project-capture))))

(ert-deftest orp-test-mode-disable-unregisters-switch-commands ()
  "Disabling the mode removes commands from `project-switch-commands'."
  (orp-test--with-mode-off
    (org-roam-project-mode 1)
    (org-roam-project-mode -1)
    (should (not (orp-test--switch-command-present-p 'org-roam-project-node-find)))
    (should (not (orp-test--switch-command-present-p 'org-roam-project-capture)))))

(provide 'org-roam-project-test)

;;; org-roam-project-test.el ends here