;; Time-stamp: <2020-04-26 20:33:20 (tslil@bison)>

;; -----------------------------------------------------------------------------
;; Mode-line
;;
;; The mode-line is set to eliminate duplicate information between buffers.
;; Everything else is intended to be displayed in another, centralised location.

(setq display-time-format "%d/%H.%M"
      display-time-default-load-average nil)
(display-time-mode 1)

(setq global-mode-string nil)
(setq-default mode-line-format
              '("" mode-line-front-space
                mode-line-modified "%@"
                " %l:%c %[" mode-line-buffer-identification "%] %I"
                " " mode-line-modes ;; (vc-mode vc-mode)
                (:eval (abbreviate-file-name default-directory))
                mode-line-misc-info mode-line-end-spaces))

;; -----------------------------------------------------------------------------
;; System information
;;
;; If running under exwm with its system tray, then put the clock and workspace
;; indicator in a posfrmae as provided by statusbar.el. Othewrise, use
;; minibuffer-line as the central location.

(if (fboundp 'exwm-systemtray-enable)
    (progn
      ;; -----------------------------------------------------------------------------
      ;; Statusbar.el
      (add-to-list 'load-path (expand-file-name "~/.emacs.d/scripts/statusbar.el/"))
      (use-package posframe :ensure t)
      (use-package statusbar
        :config
        (advice-add 'exwm-update-workspace-lighter :after #'statusbar-refresh)
        (setq statusbar-modeline-variables '(exwm-workspace-lighter display-time-string))
        (statusbar-mode 1)
        (exwm-update-workspace-lighter)))
  ;; -----------------------------------------------------------------------------
  ;; Not running under EXWM, use minibuffer-line
  ;;
  ;; First we define two ``modules'' for use in the mode-line

  ;; -----------------------------------------------------------------------------
  ;; Remind me of my mortality

  (defvar my-mortality "")

  (defun my-mortality-update ()
    (setq my-mortality
          (format "%.4f"
                  (/ (float-time
                      (time-subtract (current-time)
                                     (encode-time 0 0 0 DAY MONTH YEAR)))
                     (* 60 60 24 364.25)))))


  (defvar my-mortality-update-timer (run-at-time nil (* 60 60) 'my-mortality-update))

  ;; -----------------------------------------------------------------------------
  ;; Battery status and CPU temperature

  (defvar sys-status "")
  (defvar sys-status-cpu-temp-threshold "45")

  (defun linux-sys-status ()
    (let ((bat-s (string-trim (shell-command-to-string (expand-file-name "~/.local/bin/battery"))))
          (temp-s (if (not (file-exists-p "/sys/class/thermal/thermal_zone1/temp")) ""
                    (with-temp-buffer
                      (insert-file-contents "/sys/class/thermal/thermal_zone1/temp")
                      (let ((temp (substring-no-properties (buffer-string) 0 -4)))
                        (if (string-greaterp temp sys-status-cpu-temp-threshold)
                            (concat " " temp "C") ""))))))
      (if (and (string-blank-p bat-s) (string-blank-p temp-s))
          "" (format " [%s%s]" bat-s temp-s))))

  (defun sys-status-update ()
    (setq sys-status (linux-sys-status)))

  (defvar sys-status-update-timer (run-at-time nil 60 'sys-status-update))

  ;; -----------------------------------------------------------------------------
  ;; Minibuffer-line

  (use-package minibuffer-line
    :ensure t
    :config
    (setq minibuffer-line-refresh-interval 60
          minibuffer-line-format
          '("" display-time-string " " my-mortality sys-status))
    ;; We redefine this function to centre the text
    ;; Is there a better way?
    (defun minibuffer-line--update ()
      (with-current-buffer minibuffer-line--buffer
        (erase-buffer)
        (insert (format-mode-line minibuffer-line-format 'minibuffer-line))
        (setq fill-column (frame-width))
        (center-line)))
    (minibuffer-line-mode 1)

    (when (symbolp exwm-workspace-switch-hook)
      (push #'minibuffer-line--update exwm-workspace-switch-hook)))
  ;; really want to hook buffer changes at all, and focus
  (add-hook 'minibuffer-exit-hook #'minibuffer-line--update))

;; -----------------------------------------------------------------------------
;; Minions to clean mode-line

(use-package minions
  :ensure t
  :config
  (setq minions-mode-line-lighter ":")
  (minions-mode 1))