From 035977a89ae04d99892b3382582ec5b0b8b6a140 Mon Sep 17 00:00:00 2001
From: "Dirk-Jan C. Binnema" <djcb@djcbsoftware.nl>
Date: Sat, 28 Aug 2021 14:56:31 +0300
Subject: [PATCH] mu4e-context: make it a minor-mode

Add mu4e-context-minor-mode, for re-use in other parts of mu4e.

Update those parts + documentation.
---
 mu4e/mu4e-compose.el   | 12 ++++++---
 mu4e/mu4e-context.el   | 56 ++++++++++++++++++++++++++++--------------
 mu4e/mu4e-headers.el   |  8 +++---
 mu4e/mu4e-main.el      |  6 ++---
 mu4e/mu4e-vars.el      |  5 ----
 mu4e/mu4e-view-gnus.el | 23 +++++++----------
 mu4e/mu4e.texi         | 11 +++++++--
 7 files changed, 68 insertions(+), 53 deletions(-)

diff --git a/mu4e/mu4e-compose.el b/mu4e/mu4e-compose.el
index d7b1478e..26f367a7 100644
--- a/mu4e/mu4e-compose.el
+++ b/mu4e/mu4e-compose.el
@@ -447,7 +447,6 @@ removing the In-Reply-To header."
   (setq mu4e-compose-mode-map
         (let ((map (make-sparse-keymap)))
           (define-key map (kbd "C-S-u")   'mu4e-update-mail-and-index)
-          (define-key map (kbd "C-c C-;") 'mu4e-compose-context-switch)
           (define-key map (kbd "C-c C-u") 'mu4e-update-mail-and-index)
           (define-key map (kbd "C-c C-k") 'mu4e-message-kill-buffer)
           (define-key map (kbd "M-q")     'mu4e-fill-paragraph)
@@ -508,7 +507,12 @@ buffers; lets remap its faces so it uses the ones for mu4e."
 \\{message-mode-map}."
   (progn
     (use-local-map mu4e-compose-mode-map)
-    (mu4e-context-in-modeline)
+
+    (mu4e-context-minor-mode)
+    (define-key mu4e-context-minor-mode-map (kbd ";") nil)
+    (define-key mu4e-context-minor-mode-map (kbd "C-c C-;")
+      #'mu4e-compose-context-switch)
+    
     (set (make-local-variable 'message-signature) mu4e-compose-signature)
     ;; set this to allow mu4e to work when gnus-agent is unplugged in gnus
     (set (make-local-variable 'message-send-mail-real-function) nil)
@@ -710,8 +714,8 @@ are optional."
   (set (make-local-variable 'mu4e-compose-type) compose-type)
   (put 'mu4e-compose-type 'permanent-local t)
   ;; maybe switch the context
-  (mu4e~context-autoswitch mu4e-compose-parent-message
-                           mu4e-compose-context-policy)
+  (mu4e--context-autoswitch mu4e-compose-parent-message
+                            mu4e-compose-context-policy)
   (run-hooks 'mu4e-compose-pre-hook)
 
   ;; this opens (or re-opens) a messages with all the basic headers set.
diff --git a/mu4e/mu4e-context.el b/mu4e/mu4e-context.el
index 4282834f..300c53eb 100644
--- a/mu4e/mu4e-context.el
+++ b/mu4e/mu4e-context.el
@@ -27,11 +27,10 @@
 
 ;;; Code:
 
-(require 'cl-lib)
-(require 'mu4e-utils)
+(require 'mu4e-helpers)
 
-(defvar smtpmail-smtp-user)
-(defvar mu4e-view-date-format)
+
+;;; Configuration
 
 (defvar mu4e-contexts nil
   "The list of `mu4e-context' objects describing mu4e's contexts.")
@@ -39,16 +38,23 @@
 (defvar mu4e-context-changed-hook nil
   "Hook run just *after* the context changed.")
 
-(defvar mu4e~context-current nil
-  "The current context; for internal use.
-Use `mu4e-context-switch' to change it.")
+(defface mu4e-context-face
+  '((t :inherit mu4e-title-face :weight bold))
+  "Face for displaying the context in the modeline."
+  :group 'mu4e-faces)
+
 
+(defvar mu4e--context-current nil
+  "The current context.
+Internal; use `mu4e-context-switch' to change it.")
+
+
 (defun mu4e-context-current (&optional output)
   "Get the currently active context, or nil if there is none.
 When OUTPUT is non-nil, echo the name of the current context or
 none."
   (interactive "p")
-  (let ((ctx mu4e~context-current))
+  (let ((ctx mu4e--context-current))
     (when output
       (mu4e-message "Current context: %s"
                     (if ctx (mu4e-context-name ctx) "<none>")))
@@ -58,7 +64,7 @@ none."
   "Propertized string with the current context name.
 An empty string \"\" if there is none."
   (if (mu4e-context-current)
-      (concat "[" (propertize (mu4e~quote-for-modeline
+      (concat "[" (propertize (mu4e-quote-for-modeline
                                (mu4e-context-name (mu4e-context-current)))
                               'face 'mu4e-context-face) "]") ""))
 
@@ -83,7 +89,7 @@ An empty string \"\" if there is none."
   vars) ;; alist of variables.
 
 
-(defun mu4e~context-ask-user (prompt)
+(defun mu4e--context-ask-user (prompt)
   "Let user choose some context based on its name with PROMPT."
   (when mu4e-contexts
     (let* ((names (cl-map 'list (lambda (context)
@@ -108,13 +114,13 @@ non-nil."
          (context
           (if name
               (cdr-safe (assoc name names))
-            (mu4e~context-ask-user "Switch to context: "))))
+            (mu4e--context-ask-user "Switch to context: "))))
     (unless context (mu4e-error "No such context"))
     ;; if new context is same as old one one switch with FORCE is set.
     (when (or force (not (eq context (mu4e-context-current))))
       (when (and (mu4e-context-current)
-                 (mu4e-context-leave-func mu4e~context-current))
-        (funcall (mu4e-context-leave-func mu4e~context-current)))
+                 (mu4e-context-leave-func mu4e--context-current))
+        (funcall (mu4e-context-leave-func mu4e--context-current)))
       ;; enter the new context
       (when (mu4e-context-enter-func context)
         (funcall (mu4e-context-enter-func context)))
@@ -122,14 +128,14 @@ non-nil."
         (mapc (lambda (cell)
                 (set (car cell) (cdr cell)))
               (mu4e-context-vars context)))
-      (setq mu4e~context-current context)
+      (setq mu4e--context-current context)
 
       (run-hooks 'mu4e-context-changed-hook)
       (mu4e-message "Switched context to %s" (mu4e-context-name context))
       (force-mode-line-update))
     context))
 
-(defun mu4e~context-autoswitch (&optional msg policy)
+(defun mu4e--context-autoswitch (&optional msg policy)
   "Automatically switch to some context.
 
 When contexts are defined but there is no context yet, switch to
@@ -161,7 +167,7 @@ match, POLICY determines what to do:
 - otherwise, return nil. Effectively, this leaves the current context as it is."
   (when mu4e-contexts
     (if (eq policy 'always-ask)
-        (mu4e~context-ask-user "Select context: ")
+        (mu4e--context-ask-user "Select context: ")
       (or ;; is there a matching one?
        (cl-find-if (lambda (context)
                      (when (mu4e-context-match-func context)
@@ -170,9 +176,9 @@ match, POLICY determines what to do:
        ;; no context found yet; consult policy
        (cl-case policy
          (pick-first (car mu4e-contexts))
-         (ask (mu4e~context-ask-user "Select context: "))
+         (ask (mu4e--context-ask-user "Select context: "))
          (ask-if-none (or (mu4e-context-current)
-                          (mu4e~context-ask-user "Select context: ")))
+                          (mu4e--context-ask-user "Select context: ")))
          (otherwise nil))))))
 
 (defun mu4e-context-in-modeline ()
@@ -182,6 +188,18 @@ global-mode-line."
    (make-local-variable 'global-mode-string)
    '(:eval (mu4e-context-label))))
 
-;;; _
+(define-minor-mode mu4e-context-minor-mode
+  "Mode for switching the mu4e context."
+  :global nil
+  :init-value nil ;; disabled by default
+  :group 'mu4e
+  :lighter ""
+  :keymap
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd";") #'mu4e-context-switch)
+    map)
+  (mu4e-context-in-modeline))
+
+;;; 
 (provide 'mu4e-context)
 ;;; mu4e-context.el ends here
diff --git a/mu4e/mu4e-headers.el b/mu4e/mu4e-headers.el
index 203de0c0..fb5930d0 100644
--- a/mu4e/mu4e-headers.el
+++ b/mu4e/mu4e-headers.el
@@ -38,6 +38,7 @@
 (require 'mu4e-proc)
 (require 'mu4e-vars)
 (require 'mu4e-mark)
+(require 'mu4e-context)
 (require 'mu4e-compose)
 (require 'mu4e-actions)
 (require 'mu4e-message)
@@ -929,8 +930,6 @@ after the end of the search results."
           (define-key map (kbd "<C-kp-add>") 'mu4e-headers-split-view-grow)
           (define-key map (kbd "<C-kp-subtract>") 'mu4e-headers-split-view-shrink)
 
-          (define-key map ";" 'mu4e-context-switch)
-
           ;; switching to view mode (if it's visible)
           (define-key map "y" 'mu4e-select-other-view)
 
@@ -1133,8 +1132,6 @@ no user-interaction ongoing."
   (make-local-variable 'mu4e~highlighted-docid)
   (set (make-local-variable 'hl-line-face) 'mu4e-header-highlight-face)
 
-  (mu4e-context-in-modeline)
-
   ;; maybe update the current headers upon indexing changes
   (add-hook 'mu4e-index-updated-hook 'mu4e~headers-maybe-auto-update)
   (add-hook 'mu4e-index-updated-hook
@@ -1147,6 +1144,7 @@ no user-interaction ongoing."
    header-line-format (mu4e~header-line-format))
 
   (mu4e~mark-initialize) ;; initialize the marking subsystem
+  (mu4e-context-minor-mode)
   (hl-line-mode 1))
 
 (defun mu4e~headers-index-updated-hook-fn ()
@@ -1266,7 +1264,7 @@ docid is not found."
                    `(:eval
                      (concat
                       (propertize
-                       (mu4e~quote-for-modeline ,mu4e~headers-mode-line-label)
+                       (mu4e-quote-for-modeline ,mu4e~headers-mode-line-label)
                        'face 'mu4e-modeline-face)
                       " "
                       (if (and mu4e-display-update-status-in-modeline
diff --git a/mu4e/mu4e-main.el b/mu4e/mu4e-main.el
index 839ccf6b..6e01ceb8 100644
--- a/mu4e/mu4e-main.el
+++ b/mu4e/mu4e-main.el
@@ -1,6 +1,6 @@
 ;;; mu4e-main.el -- part of mu4e, the mu mail user agent -*- lexical-binding: t -*-
 
-;; Copyright (C) 2011-2020 Dirk-Jan C. Binnema
+;; Copyright (C) 2011-2021 Dirk-Jan C. Binnema
 
 ;; Author: Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 ;; Maintainer: Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
@@ -43,8 +43,6 @@
   This also hides the warning if your `user-mail-address' is not
 part of the personal addresses.")
 
-
-
 (defvar mu4e-main-hide-fully-read nil
   "When set to t, do not hide bookmarks or maildirs that have
 no unread messages.")
@@ -87,7 +85,7 @@ no unread messages.")
 \\{mu4e-main-mode-map}."
   (setq truncate-lines t
         overwrite-mode 'overwrite-mode-binary)
-  (mu4e-context-in-modeline)
+  (mu4e-context-minor-mode)
   (set (make-local-variable 'revert-buffer-function) #'mu4e~main-view-real))
 
 
diff --git a/mu4e/mu4e-vars.el b/mu4e/mu4e-vars.el
index 251c1c9f..3d903ea8 100644
--- a/mu4e/mu4e-vars.el
+++ b/mu4e/mu4e-vars.el
@@ -764,11 +764,6 @@ I.e. a message with the draft flag set."
   "Face for a header title in the headers view."
   :group 'mu4e-faces)
 
-(defface mu4e-context-face
-  '((t :inherit mu4e-title-face :weight bold))
-  "Face for displaying the context in the modeline."
-  :group 'mu4e-faces)
-
 (defface mu4e-modeline-face
   '((t :inherit font-lock-string-face :weight bold))
   "Face for the query in the mode-line."
diff --git a/mu4e/mu4e-view-gnus.el b/mu4e/mu4e-view-gnus.el
index f4350e2e..2b73f649 100644
--- a/mu4e/mu4e-view-gnus.el
+++ b/mu4e/mu4e-view-gnus.el
@@ -28,6 +28,7 @@
 ;;; Code:
 
 (require 'mu4e-view-common)
+(require 'mu4e-context)
 (require 'calendar)
 (require 'gnus-art)
 
@@ -266,9 +267,7 @@ This is useful for advising some Gnus-functionality that does not work in mu4e."
     (define-key map "A" #'mu4e-view-mime-part-action)
     (define-key map "e" #'mu4e-view-save-attachments)
 
-    (define-key map ";" #'mu4e-context-switch)
-
-          ;; toggle header settings
+    ;; toggle header settings
     (define-key map "O" #'mu4e-headers-change-sorting)
     (define-key map "P" #'mu4e-headers-toggle-threading)
     (define-key map "Q" #'mu4e-headers-toggle-full-search)
@@ -403,16 +402,6 @@ This is useful for advising some Gnus-functionality that does not work in mu4e."
 
 (defvar mu4e-view-mode-abbrev-table nil)
 
-(defun mu4e~view-mode-body ()
-  "Body of the mode-function."
-  (use-local-map mu4e-view-mode-map)
-  (mu4e-context-in-modeline)
-  (setq buffer-undo-list t);; don't record undo info
-  ;; autopair mode gives error when pressing RET
-  ;; turn it off
-  (when (boundp 'autopair-dont-activate)
-    (setq autopair-dont-activate t)))
-
 ;;  "Define the major-mode for the mu4e-view."
 (define-derived-mode mu4e-view-mode gnus-article-mode "mu4e:view"
   "Major mode for viewing an e-mail message in mu4e.
@@ -430,7 +419,13 @@ Based on Gnus' article-mode."
               (lambda(func &rest args)
                 (if (mu4e~view-mode-p)
                     "." (apply func args))))
-  (mu4e~view-mode-body))
+  (use-local-map mu4e-view-mode-map)
+  (mu4e-context-minor-mode)
+  (setq buffer-undo-list t);; don't record undo info
+  ;; autopair mode gives error when pressing RET
+  ;; turn it off
+  (when (boundp 'autopair-dont-activate)
+    (setq autopair-dont-activate t)))
 
 ;;; Massaging the message view
 
diff --git a/mu4e/mu4e.texi b/mu4e/mu4e.texi
index ec2f8544..43ccce2a 100644
--- a/mu4e/mu4e.texi
+++ b/mu4e/mu4e.texi
@@ -1005,7 +1005,6 @@ E            edit (only allowed for draft messages)
 
 misc
 ----
-;            switch context
 a            execute some custom action on a header
 |            pipe message through shell command
 C-+,C--      increase / decrease the number of headers shown
@@ -1014,6 +1013,10 @@ C-S-u        update mail & reindex
 q            leave the headers buffer
 @end verbatim
 
+Furthermore, a number of keybindings are available through minor modes:
+@itemize
+@item Context; see @pxref{Contexts}.
+@end itemize
 
 @node HV Marking
 @section Marking
@@ -1300,7 +1303,6 @@ A            execute some custom action on the message's MIME-parts
 
 misc
 ----
-;            switch context
 .            show the raw message view. 'q' takes you back.
 C-+,C--      increase / decrease the number of headers shown
 H            get help
@@ -1308,6 +1310,11 @@ C-S-u        update mail & reindex
 q            leave the message view
 @end verbatim
 
+Furthermore, a number of keybindings are available through minor modes:
+@itemize
+@item Context; see @pxref{Contexts}.
+@end itemize
+
 For the marking commands, please refer to @ref{Marking messages}.
 
 @node MSGV Rich-text and images