;;; packages.el --- gnus Layer packages File for Spacemacs
;;
;; Copyright (c) 2012-2021 Sylvain Benner & Contributors
;;
;; Author: Sylvain Benner <sylvain.benner@gmail.com>
;; URL: https://github.com/syl20bnr/spacemacs
;;
;; This file is not part of GNU Emacs.
;;
;;; License: GPLv3

(defconst gnus-packages
  '(
    gnus
    window-purpose
    persp-mode))

(defun gnus/pre-init-persp-mode ()
  (spacemacs|use-package-add-hook persp-mode
    :post-config
    (progn
      (spacemacs|define-custom-layout gnus-spacemacs-layout-name
        :binding gnus-spacemacs-layout-binding
        :body
        (call-interactively 'gnus)))))

(defun gnus/init-gnus ()
  "Initialize my package"
  (use-package gnus
    :defer t
    :commands gnus
    :init
    (progn
      (spacemacs/declare-prefix "aeg" "gnus" "Gnus newsreader")
      (spacemacs/set-leader-keys
        "aegg" 'gnus
        "aegs" 'gnus-slave
        "aegu" 'gnus-unplugged
        "aego" 'gnus-slave-unplugged)
      (spacemacs/declare-prefix-for-mode 'message-mode "mi" "insert")
      (spacemacs/set-leader-keys-for-major-mode 'message-mode
        ;; RFC 1855
        "miF" 'flame-on)
      ;; NOTE: If any of the following variables are modified,
      ;; also update their values in: `gnus/README.org'
      (setq-default
       gnus-summary-line-format "%U%R%z %(%&user-date;  %-15,15f  %B (%c) %s%)\n"
       gnus-user-date-format-alist '((t . "%Y-%m-%d %H:%M"))
       gnus-group-line-format "%M%S%p%P%5y:%B %G\n";;"%B%(%g%)"
       gnus-summary-thread-gathering-function 'gnus-gather-threads-by-references
       gnus-thread-sort-functions '(gnus-thread-sort-by-most-recent-date)
       gnus-ignored-newsgroups "^to\\.\\|^[0-9. ]+\\( \\|$\\)\\|^[\”]\”[#’()]"
       gnus-sum-thread-tree-false-root ""
       gnus-sum-thread-tree-indent " "
       gnus-sum-thread-tree-leaf-with-other "├► "
       gnus-sum-thread-tree-root ""
       gnus-sum-thread-tree-single-leaf "╰► "
       gnus-sum-thread-tree-vertical "│"
       gnus-article-browse-delete-temp t
       gnus-treat-strip-trailing-blank-lines 'last
       gnus-keep-backlog 'nil
       gnus-summary-display-arrow nil ; Don't show that annoying arrow:
       gnus-mime-display-multipart-related-as-mixed t ; Show more MIME-stuff:
       gnus-auto-select-first nil ; Don't get the first article automatically:
       smiley-style 'medium
       gnus-keep-backlog '0))
    :config
    (progn
      ;; No primary server
      (setq gnus-select-method '(nnnil ""))

      ;; Use topics per default
      (add-hook 'gnus-group-mode-hook 'gnus-topic-mode)

      (setq gnus-visible-headers
            "^From:\\|^Reply-To\\|^Organization:\\|^To:\\|^Cc:\\|^Newsgroups:\\|^Subject:\\|^Date:\\|^Gnus")

      ;; Show the article headers in this order.
      (setq gnus-sorted-header-list
            '("^From:" "^Reply-To" "^Organization:" "^To:" "^Cc:" "^Newsgroups:"
              "^Subject:" "^Date:" "^Gnus"))

      (require 'browse-url)
      (require 'nnrss)
      (defun spacemacs/gnus-flame-on ()
        "Most important email function, for RFC1855 compliance."
        ;; https://tools.ietf.org/html/rfc1855
        (interactive)
        (insert "FLAME ON:\n")
        (insert "FLAME OFF\n")
        (forward-line -2)
        (end-of-line))
      (defun spacemacs/browse-nnrss-url (arg)
        "Open RSS Article directy in the browser"
        (interactive "p")
        (let ((url (assq nnrss-url-field
                         (mail-header-extra
                          (gnus-data-header
                           (assq (gnus-summary-article-number)
                                 gnus-newsgroup-data))))))
          (if url
              (progn
                (browse-url (cdr url))
                (gnus-summary-mark-as-read-forward 1))
            (gnus-summary-scroll-up arg))))
      (add-to-list 'nnmail-extra-headers nnrss-url-field)

      (evilified-state-evilify gnus-group-mode gnus-group-mode-map
        (kbd "g r") 'gnus-group-get-new-news
        (kbd "O") 'gnus-group-group-map)
      (evilified-state-evilify gnus-server-mode gnus-server-mode-map)
      (evilified-state-evilify gnus-browse-mode gnus-browse-mode-map)
      (evilified-state-evilify gnus-article-mode gnus-article-mode-map)
      (evilified-state-evilify gnus-summary-mode gnus-summary-mode-map
        (kbd "J") 'gnus-summary-next-article
        (kbd "K") 'gnus-summary-prev-article
        (kbd "<RET>") 'spacemacs/browse-nnrss-url))))

(defun gnus/post-init-window-purpose ()
  (purpose-set-extension-configuration
   :gnus-layer
   (purpose-conf :mode-purposes '((gnus-group-mode . mail)
                                  (gnus-server-mode . mail)
                                  (gnus-browse-mode . mail)
                                  (gnus-article-mode . mail)
                                  (gnus-summary-mode . mail)))))
