;;; gnus.el -*- lexical-binding: t; coding: utf-8-unix -*-

;; Author: Case Duckworth <acdw@acdw.net>
;; Created: Sometime during Covid-19, 2020
;; Keywords: configuration
;; URL: https://tildegit.org/acdw/emacs

;; This file is NOT part of GNU Emacs.

;;; License:
;; Everyone is permitted to do whatever with this software, without
;; limitation.  This software comes without any warranty whatsoever,
;; but with two pieces of advice:
;; - Don't hurt yourself.
;; - Make good choices.

;;; Code:

;;; Private files
(require 'acdw-private)

;;; Select Methods
(setq gnus-select-method '(nnnil ""))

(add-hook 'gnus-startup-hook
          (defun gnus-startup@feed-setup ()
            (cond ((fboundp #'gnus/init-feed-list)
                   (gnus/init-feed-list))
                  ((and (fboundp #'gnus/import-feed-list)
                        (file-exists-p (expand-file-name
                                        "feeds.txt" user-emacs-directory)))
                   (gnus/import-feed-list (expand-file-name
                                           "feeds.txt" user-emacs-directory)))
                  (t (message "Oops, no feeds :/")))))

;;; Gnus cloud
(setq gnus-cloud-storage-method nil ; Don't always have GPG or gzip
      gnus-cloud-covered-servers '("nntp:news.tilde.club"
                                   "nntp:news.gwene.org"
                                   "nntp:news.gmane.io"))
(add-hook 'gnus-started-hook #'gnus-cloud-download-all-data)
(add-hook 'gnus-exit-gnus-hook #'gnus-cloud-upload-all-data)

;;; Gnus behavior options
(setq gnus-gcc-mark-as-read t
      message-signature (or (file-exists-p message-signature-file)
                            "~ acdw")
      gnus-startup-file (expand-file-name "newsrc" gnus-home-directory)
      gnus-save-newsrc-file nil
      gnus-read-newsrc-file nil
      gnus-read-active-file 'some
      gnus-always-read-dribble-file t
      gnus-interactive-exit nil
      gnus-use-cache t)

;; Keybindings
(define-key gnus-group-mode-map (kbd "q")
  (defun gnus-cloud-upload-and-bury-buffer ()
    (interactive)
    (gnus-cloud-upload-all-data)
    (bury-buffer)))
(define-key gnus-group-mode-map (kbd "Q") #'gnus-group-exit)
(define-key gnus-group-mode-map (kbd "C-q") #'gnus-group-quit)

;;; Other parameters
(setq gnus-parameters
      '(("fastmail.com:.*"
         (display . 200)
         (expiry-wait . immediate)
         (expiry-target . "nnimap+fastmail.com:Archive"))))

;;; Gnus UI options
(setq gnus-thread-sort-functions '(gnus-thread-sort-by-most-recent-date
                                   (not gnus-thread-sort-by-number))
      gnus-use-cache t
      gnus-summary-thread-gathering-function #'gnus-gather-threads-by-subject
      gnus-thread-hide-subtree t
      gnus-thread-ignore-subject t
      gnus-html-frame-width fill-column)

(when window-system
  (setq gnus-sum-thread-tree-indent "  ")
  (setq gnus-sum-thread-tree-root "● ")
  (setq gnus-sum-thread-tree-false-root "○ ")
  (setq gnus-sum-thread-tree-single-indent "◎ ")
  (setq gnus-sum-thread-tree-vertical        "│")
  (setq gnus-sum-thread-tree-leaf-with-other "├─ ")
  (setq gnus-sum-thread-tree-single-leaf     "╰─ "))

(setq gnus-summary-line-format
      (concat
       "%0{%U%R%z%}"
       "%3{│%}" "%1{%d%}" "%3{│%}"      ; date
       "  "
       "%4{%-20,20f%}"                  ; name
       "  "
       "%3{│%}"
       " "
       "%1{%B%}"
       "%s\n"))

(setq gnus-summary-display-arrow t)

(add-hook 'gnus-group-mode-hook #'hl-line-mode)
(add-hook 'gnus-article-mode-hook #'acdw/reading-mode)

;;; MIME types
(setq mm-discouraged-alternatives '("text/html"
                                    "text/richtext"))

(with-eval-after-load 'mailcap
  (cond ((eq system-type 'darwin))
        ((eq system-type 'windows-nt))
        (t (mailcap-parse-mailcaps))))

;;; Composing mail
(add-hook 'message-mode-hook
          (defun message-mode@setup ()
            (flyspell-mode +1)
            (local-set-key (kbd "TAB") #'bbdb-complete-mail)))

;;; Packages

;; searching (?)
(require 'nnir)

;; contacts
(setup (:straight bbdb)
  (require 'bbdb)
  (bbdb-initialize 'message 'gnus 'mail)
  (bbdb-insinuate-message)
  (add-hook 'gnus-startup-hook 'bbdb-insinuate-gnus)
  (:option bbdb/gnus-summary-prefer-real-names t
           bbdb/mail-auto-create-p t
           bbdb/news-auto-create-p t
           bbdb-use-pop-up t
           bbdb-offer-save 1
           bbdb-update-records-p t))

;;; Functions
;; see https://wpc.io/blog/posts/bulk-import-rss-feeds-to-gnus-via-gwene.html
(defun gnus/slurp (file)
  "Read FILE into a string."
  (with-temp-buffer
    (insert-file-contents file)
    (buffer-substring-no-properties
     (point-min)
     (point-max))))

(defun gnus/import-feed-list (path)
  "Import list of NNTP feeds from file at PATH."
  (interactive "F")
  (let ((feeds (split-string (gnus/slurp path) "\n" t)))
    (cl-loop for feed in feeds
             do (with-message (format "Subscribing to %s" feed)
                  (gnus-subscribe-group feed)))))