;;; Provides Stride minor mode.
;;; 
(require 'eww)
(require 'eww-http-code-advice)

(defgroup stride nil
  "Stride custom group."
  :group 'novels)

(defcustom stride-nav-file (concat user-emacs-directory "stride-nav.el")
  "File that Stride reads site navigation info from."
  :group 'stride)

;; (defcustom stride-nav
;;   (with-temp-buffer
;;     (insert-file-contents stride-nav-file)
;;     (read (buffer-string)))
;;   "Stride navigation list."
;;   :type '()
;;   :group 'stride)

(defun stride-read-file ()
  "Read `stride-nav' from `stride-nav-file' file."
  (interactive)
  (with-temp-buffer
    (insert-file-contents stride-nav-file)
    (setq stride-nav (read (buffer-string)))))

(defun stride-write-file ()
  "Write `stride-nav' to `stride-nav-file' file."
  (interactive)
  (let ((inhibit-message t))
    (with-temp-buffer
      (insert (pp stride-nav))
      (write-file stride-nav-file))) )

(defun stride-match ()
  "Return matching stride-nav member."
  (interactive)
  ;; (defvar-local stride-nav '())
  (catch 'break
    (dolist (s stride-nav)
      (if (string-match (car s) (plist-get eww-data :url))
	  (progn
	    (throw 'break s))))))

(defun stride-head ()
  "Attempt to match site in stride-nav list and go to chapter heading."
  (interactive)
  ;;; first version. Looks for error message string in buffer contents.
  ;; (catch 'break
  ;;   (unless
  ;; 	(catch 'reload
  ;; 	  (let ((line (buffer-substring-no-properties 1 (line-end-position))))
  ;; 	    (mapcan
  ;; 	     (lambda (substr)
  ;; 	       (if (search substr line)
  ;; 		   (throw 'break (eww-reload))))
  ;; 	     '("400 Bad Request"
  ;; 	       "404 File Not Found")))))
  ;;   (eval (car (cdr (stride-match)))))

  ;;; second version. Uses error code in eww-data to determine response. Requires eww-render-fix.
  ;; (let ((status (third (plist-get eww-data :error))))
  ;;   (if (member status '(400 404))
  ;; 	(eww-reload)
  ;;     (eval (nth 1 (stride-match)))))

  ;;; Third version. Only gives eww-reload 3 tries.
  (let ((status (third (plist-get eww-data :error)))
	(tries (or (plist-get eww-data :tries) 1)))
    (if (eq status 400)
	(when (<= tries 3)
	  (plist-put eww-data :tries (+ tries 1))
	  (message "HTTP/1.1 ERROR 400, retry count: %i" (+ tries 1))
	  (eww-reload))
      (plist-put eww-data :tries 1)
      (eval (second (stride-match)))))
  )

(defun stride-forward ()
  "Goes to next chapter if in view, else advances to next page.
TODO: move function definition to stride-nav for more flexibility
when dealing with dificult sites. then eval the lisp here."
  (interactive)
  (move-to-window-line -1)
  (setq-local bottom (point))
  (move-to-window-line 0)
  (if (re-search-forward
       (car (cdr (cdr (stride-match))))
       bottom t)
      (progn
  	(backward-char)
  	(eww-follow-link))
    (scroll-up-command)))

(defun stride-eww-after-render-hook ()
  (progn
    (stride-head)))

(setq stride-mode-map (make-sparse-keymap))
(define-key stride-mode-map [?\s] 'stride-forward)
;; (define-key stride-mode-map (kbd "<mouse-5>") 'stride-forward)

(define-minor-mode stride-mode
  "More intelligent space bar navigation."
  :lighter " Stride"
  :keymap stride-mode-map
  (if stride-mode
      (progn
	(add-hook 'eww-after-render-hook 'stride-eww-after-render-hook nil t)
	(setq stride-nav (with-temp-buffer
				 (insert-file-contents stride-nav-file)
				 (read (buffer-string))))
	;; (setq-local stride-mode-on t)
	;; (stride-update)
	)
    (remove-hook 'eww-after-render-hook 'stride-eww-after-render-hook t) ))

(provide 'stride)

;; Local Variables:
;; nameless-current-name: "stride"
;; End: