;;; config/tutorial/autoload/tutorial.el -*- lexical-binding: t; -*-

(defvar doom-tutorial-hist-file
  (expand-file-name "tutorial-progress.el" doom-cache-dir)
  "Directory where tutorial progress information is saved.")

(defvar doom-tutorial--progress
  (when (file-exists-p doom-tutorial-hist-file)
    (with-temp-buffer
      (insert-file-contents doom-tutorial-hist-file)
      (read (current-buffer))))
  "An alist of tutorials and progress information.")

(defun doom-tutorial--save-progress ()
  "Write `doom-tutorial--progress' to `doom-tutorial-hist-file'."
  (with-temp-buffer
    (insert
     ";; -*- mode: emacs-lisp -*-\n"
     ";; Tutorial progress file, automatically generated by `doom-tutorial--save-progress'.\n"
     "\n")
    (let ((print-length nil)
          (print-level nil)
          (print-quoted t))
      (prin1 doom-tutorial--progress
             (current-buffer)))
    (insert ?\n)
    (condition-case err
        (write-region (point-min) (point-max) doom-tutorial-hist-file nil
                      (unless (called-interactively-p 'interactive) 'quiet))
      (file-error
       (lwarn '(doom-tutorial-hist-file) :warning "Error writing `%s': %s"
              doom-tutorial-hist-file (caddr err))))))

(defvar doom-tutorials--loaded nil
  "An alist of loaded tutorials.")

(defun doom-tutorial-normalise-plist (somelist)
  (cdr (cl-reduce
        (lambda (result new)
          (if (keywordp new)
              (progn (push new result)
                     (push nil result))
            (push new (car result)))
          result)
        (nreverse somelist)
        :initial-value (list nil))))

;;;###autoload
(defmacro define-tutorial! (name &optional docstring &rest body)
  (declare (doc-string 2) (indent defun))
  (unless (stringp docstring)
    (push docstring body)
    (setq docstring nil))
  (let ((parameters (doom-tutorial-normalise-plist body)))
    (when (plist-get parameters :setup)
      (plist-put parameters :setup
                 (append (list #'progn) (plist-get parameters :setup))))
    (when (plist-get parameters :teardown)
      (plist-put parameters :teardown
                 (append (list #'progn) (plist-get parameters :teardown))))
    `(progn
       (defun ,(intern (format "doom-tutorial-%s" name)) (&optional autotriggered)
         ,docstring
         (interactive "p")
         (if autotriggered
             (doom-tutorial-run ',name)
           (doom-tutorial-run-maybe ',name)))
       (doom-tutorial-register ',name ',parameters))))

(defun doom-tutorial-register (name parameters)
  (push (cons name parameters) doom-tutorials--loaded)
  (unless (assoc name doom-tutorial--progress)
    (push (list name :skipped nil :complete nil :page 0)
          doom-tutorial--progress))
  (dolist (target (plist-get parameters :triggers))
    (advice-add target :after name))
  (dolist (filepattern (plist-get parameters :file-triggers))
    (add-to-list 'doom-tutorials--file-triggers (cons (eval filepattern) name))))

;;;###autoload
(defun doom-tutorial-load-modules ()
  (let (loaded-tutorials)
    (maphash (lambda (key _plist)
               (let ((tutorial-file (doom-module-path (car key) (cdr key) "tutorial.el")))
                 (when (file-exists-p tutorial-file)
                   (push (cdr key) loaded-tutorials)
                   (load tutorial-file 'noerror 'nomessage))))
             doom-modules)
    loaded-tutorials))