From 1aa7d52d16d3b29ce111e7b21ad7ca2492f91e91 Mon Sep 17 00:00:00 2001
From: Jessie Hildebrandt <jessieh@jessieh.net>
Date: Thu, 22 Dec 2022 06:12:01 -0500
Subject: [PATCH] Refactor project code for 2.0.0

---
 README.md    |  55 ++-
 mood-line.el | 923 ++++++++++++++++++++++++++++++++++++++-------------
 2 files changed, 742 insertions(+), 236 deletions(-)

diff --git a/README.md b/README.md
index bcfd41b..15fc71a 100644
--- a/README.md
+++ b/README.md
@@ -5,23 +5,22 @@
 
 ## About
 
-`mood-line` is a minimal mode-line configuration that aims to replicate some of the features of the
-[doom-modeline](https://github.com/seagle0128/doom-modeline)
-package.
+mood-line is a minimal mode-line configuration that aims to replicate some of the features of the
+more advanced [doom-modeline](https://github.com/seagle0128/doom-modeline) package.
 
 ## Features
 
 * Clean, minimal design
 
+* Customizable glyph sets
+
 * Anzu and multiple-cursors counters
 
 * Encoding and EOL style indicator
 
 * Version control status indicator
 
-* Flycheck status indicator
-
-* Flymake support
+* Custom Flycheck/Flymake indicator
 
 * Lightweight with no dependencies
 
@@ -29,13 +28,49 @@ package.
 
 ![Preview Image](https://gitlab.com/jessieh/mood-line/raw/assets/mood-line.png "Preview Image")
 
-## Installation
+## Configuration
 
-To enable `mood-line`, place this in your configuration file after loading the package:
+You can install mood-line directly via `package-install` from [MELPA](https://melpa.org/).
+After installation, you can activate the global minor mode with `M-x mood-line-mode`.
+Deactivating `mode-line-mode` will restore the default `mode-line-format`.
 
-`(mood-line-mode)`
+If you are a user of `use-package`, it is easy to configure mood-line directly in your init.el:
 
-Disabling `mood-line` can be accomplished by toggling `mood-line-mode` off.
+```elisp
+(use-package mood-line
+
+  ;; Enable mood-line
+  :config
+  (mood-line-mode)
+
+  ;; Use pretty Fira Code-compatible glyphs
+  :custom
+  (mood-line-glyph-alist . mood-line-glyphs-fira-code))
+```
+
+By default, mood-line will use basic ASCII character glyphs to decorate mode line segments.
+If you'd like to see prettier Unicode glyphs, you can change the value of `mood-line-glyph-alist`:
+
+```elisp
+;; The default set of glyphs:
+;;   * myModifiedFile.js  Replace*3                 + main  Javascript  ! Issues: 2
+(setq mood-line-glyph-alist mood-line-glyphs-ascii)
+
+;; A set of Fira Code-compatible Unicode glyphs:
+;;   ● myModifiedFile.js  Replace×3                 + main  JavaScript  → Issues: 2
+(setq mood-line-glyph-alist mood-line-glyphs-fira-code)
+
+;; A set of Unicode glyphs:
+;;   ● myModifiedFile.js  Replace✕3                 🞤 main  JavaScript  ⚑ Issues: 2
+(setq mood-line-glyph-alist mood-line-glyphs-unicode)
+```
+
+If you'd like to supply your own glyphs, you can use the customization interface
+(`M-x customize-variable mood-line-glyph-alist`) or view the documentation
+(`M-x describe-variable mood-line-glyph-alist`) for more information.
+
+You can further tweak the behavior and appearance of mood-line by viewing the customizable variables
+and faces in the `mood-line` and `mood-line-faces` customization groups. (`M-x customize-group mood-line`)
 
 ## Feedback
 
diff --git a/mood-line.el b/mood-line.el
index 0f613be..1e8157f 100644
--- a/mood-line.el
+++ b/mood-line.el
@@ -1,27 +1,27 @@
-;;; mood-line.el --- A minimal mode-line inspired by doom-modeline -*- lexical-binding: t; -*-
+;;; mood-line.el --- A minimal mode line inspired by doom-modeline -*- lexical-binding: t; -*-
 
 ;; Author: Jessie Hildebrandt <jessieh.net>
 ;; Homepage: https://gitlab.com/jessieh/mood-line
 ;; Keywords: mode-line faces
-;; Version: 1.2.5
+;; Version: 2.0.0
 ;; Package-Requires: ((emacs "25.1"))
 
 ;; This file is not part of GNU Emacs.
 
 ;;; Commentary:
 ;;
-;; mood-line is a minimal mode-line configuration that aims to replicate
-;; some of the features of the doom-modeline package.
+;; mood-line is a minimal mode line configuration that aims to replicate
+;; some of the features of the more advanced doom-modeline package.
 ;;
 ;; Features offered:
 ;; * Clean, minimal design
+;; * Customizable glyph sets
 ;; * Anzu and multiple-cursors counter
 ;; * Version control status indicator
-;; * Flycheck status indicator
-;; * Flymake support
+;; * Custom Flycheck/Flymake indicator
 ;; * Lightweight with no dependencies
 ;;
-;; To enable mood-line:
+;; To activate mood-line:
 ;; (mood-line-mode)
 
 ;;; License:
@@ -43,35 +43,132 @@
 
 ;;; Code:
 
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Variable declarations
+;; Byte-compiler declarations
 ;;
+;; -------------------------------------------------------------------------- ;;
+
+;; ---------------------------------- ;;
+;; External variable defs
+;; ---------------------------------- ;;
+
+(defvar anzu--cached-count)
+(defvar anzu--current-position)
+(defvar anzu--overflow-p)
+(defvar anzu--total-matched)
 
 (defvar flycheck-current-errors)
-(defvar flymake--mode-line-format)
-(defvar anzu-cons-mode-line-p)
-(defvar anzu--state)
-(defvar anzu--cached-count)
-(defvar anzu--overflow-p)
-(defvar anzu--current-position)
-(defvar anzu--total-matched)
-(defvar multiple-cursors-mode)
 
-;;
-;; Function prototypes
-;;
+;; ---------------------------------- ;;
+;; External function decls
+;; ---------------------------------- ;;
+
+(declare-function cl-struct-slot-value "cl-macs" (struct-type slot-name inst))
 
 (declare-function flycheck-count-errors "flycheck" (errors))
+
+(declare-function flymake-running-backends "flymake" ())
+(declare-function flymake-reporting-backends "flymake" ())
+
 (declare-function mc/num-cursors "multiple-cursors" ())
 
+(declare-function string-blank-p "subr-x" (string))
+
+(declare-function warning-numeric-level "warnings" (level))
+
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Config
+;; Constants
 ;;
+;; -------------------------------------------------------------------------- ;;
+
+(defconst mood-line-glyphs-ascii
+  '((:checker-info . ?i)
+    (:checker-issues . ?!)
+    (:checker-good . ?+)
+    (:checker-checking . ?-)
+    (:checker-errored . ?x)
+    (:checker-interrupted . ?=)
+
+    (:vc-added . ?+)
+    (:vc-needs-merge . ?>)
+    (:vc-needs-update . ?v)
+    (:vc-conflict . ?x)
+    (:vc-good . ?-)
+
+    (:buffer-narrowed . ?v)
+    (:buffer-modified . ?*)
+    (:buffer-read-only . ?#)
+
+    (:count-separator . ?*))
+  "Set of ASCII glyphs for use with mood-line.")
+
+(defconst mood-line-glyphs-fira-code
+  '((:checker-info . ?↳)
+    (:checker-issues . ?→)
+    (:checker-good . ?✓)
+    (:checker-checking . ?⟳)
+    (:checker-errored . ?x)
+    (:checker-interrupted . ?=)
+
+    (:vc-added . ?+)
+    (:vc-needs-merge . ?⟷)
+    (:vc-needs-update . ?↓)
+    (:vc-conflict . ?x)
+    (:vc-good . ?✓)
+
+    (:buffer-narrowed . ?▼)
+    (:buffer-modified . ?●)
+    (:buffer-read-only . ?■)
+
+    (:count-separator . ?×))
+  "Set of Fira Code-compatible glyphs for use with mood-line.")
+
+(defconst mood-line-glyphs-unicode
+  '((:checker-info . ?🛈)
+    (:checker-issues . ?⚑)
+    (:checker-good . ?✔)
+    (:checker-checking . ?🗘)
+    (:checker-errored . ?✖)
+    (:checker-interrupted . ?⏸)
+
+    (:vc-added . ?🞤)
+    (:vc-needs-merge . ?⟷)
+    (:vc-needs-update . ?↓)
+    (:vc-conflict . ?✖)
+    (:vc-good . ?✔)
+
+    (:buffer-narrowed . ?▼)
+    (:buffer-modified . ?●)
+    (:buffer-read-only . ?■)
+
+    (:count-separator . ?✕))
+  "Set of Unicode glyphs for use with mood-line.")
+
+;; -------------------------------------------------------------------------- ;;
+;;
+;; Custom definitions
+;;
+;; -------------------------------------------------------------------------- ;;
+
+;; ---------------------------------- ;;
+;; Group definitions
+;; ---------------------------------- ;;
 
 (defgroup mood-line nil
-  "A minimal mode-line configuration inspired by doom-modeline."
+  "A minimal mode line configuration."
   :group 'mode-line)
 
+(defgroup mood-line-faces nil
+  "Faces used by mood-line."
+  :group 'mood-line
+  :group 'faces)
+
+;; ---------------------------------- ;;
+;; Variable definitions
+;; ---------------------------------- ;;
+
 (defcustom mood-line-show-eol-style nil
   "When non-nil, show the EOL style of the current buffer."
   :group 'mood-line
@@ -87,6 +184,48 @@
   :group 'mood-line
   :type 'boolean)
 
+(defcustom mood-line-glyph-alist mood-line-glyphs-ascii
+  "Alist mapping glyph names to characters used to draw some mode line segments.
+
+mood-line includes several sets of glyphs by default:
+
+`mood-line-glyphs-ascii'     | Basic ASCII character glyphs
+`mood-line-glyphs-fira-code' | Fira Code-compatible glyphs
+`mood-line-glyphs-unicode'   | Fancy unicode glyphs
+
+Note that if a character provided by a glyph set is not included in your default
+font, the editor will render it with a fallback font.  If your fallback font is
+not the same height as your default font, the mode line may unexpectedly grow
+or shrink.
+
+Keys are names for different mode line glyphs, values are characters for that
+glyph.  Glyphs used by mood-line include:
+
+`:checker-info'        | Syntax checker reports notes
+`:checker-issues'      | Syntax checker reports issues
+`:checker-good'        | Syntax checker reports no issues
+`:checker-checking'    | Syntax checker is running
+`:checker-errored'     | Syntax checker is stopped due to an error
+`:checker-interrupted' | Syntax checker is paused
+
+`:vc-added'            | VC backend reports additions/changes
+`:vc-needs-merge'      | VC backend reports required merge
+`:vc-needs-update'     | VC backend reports upstream is ahead of local
+`:vc-conflict'         | VC backend reports conflict
+`:vc-good'             | VC backend has nothing to report
+
+`:buffer-modified'     | File-backed buffer is modified
+`:buffer-read-only'    | File-backed buffer is read-only
+
+`:count-separator'     | Separates some indicator names from numerical counts
+
+`mood-line-glyphs-ascii' will be used as a fallback wherever the a glyph may be
+found to be missing in `mood-line-glyph-alist'."
+  :group 'mood-line
+  :type `(alist :tag "Character map alist"
+                :key-type (symbol :tag "Glyph name")
+                :value-type (character :tag "Character to use")))
+
 (defcustom mood-line-evil-state-alist
   '((normal . ("<N>" . font-lock-variable-name-face))
     (insert . ("<I>" . font-lock-string-face))
@@ -119,54 +258,70 @@ The `Face' may be either a face symbol or a property list of key-value pairs
           :value-type
           (cons (string :tag "Display Text") (choice :tag "Face" face plist))))
 
+;; ---------------------------------- ;;
+;; Face definitions
+;; ---------------------------------- ;;
+
 (defface mood-line-buffer-name
   '((t (:inherit (mode-line-buffer-id))))
   "Face used for the `buffer-name'."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-major-mode
   '((t (:inherit (bold))))
   "Face used for the major mode indicator."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-status-neutral
   '((t (:inherit (shadow) :weight normal)))
   "Face used for neutral or inactive status indicators."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-status-info
   '((t (:inherit (font-lock-keyword-face) :weight normal)))
   "Face used for generic status indicators."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-status-success
   '((t (:inherit (success) :weight normal)))
   "Face used for success status indicators."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-status-warning
   '((t (:inherit (warning) :weight normal)))
   "Face for warning status indicators."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-status-error
   '((t (:inherit (error) :weight normal)))
   "Face for error status indicators."
-  :group 'mood-line)
+  :group 'mood-line-faces)
 
 (defface mood-line-unimportant
-  '((t (:inherit (shadow))))
-  "Face used for less important mode-line elements."
-  :group 'mood-line)
+  '((t (:inherit (shadow) :weight normal)))
+  "Face used for less important mode line elements."
+  :group 'mood-line-faces)
 
 (defface mood-line-modified
   '((t (:inherit (error) :weight normal)))
-  "Face used for the 'modified' indicator symbol."
-  :group 'mood-line)
+  "Face used for the ':buffer-modified' indicator."
+  :group 'mood-line-faces)
 
+;; -------------------------------------------------------------------------- ;;
 ;;
 ;; Helper functions
 ;;
+;; -------------------------------------------------------------------------- ;;
+
+(defun mood-line--get-glyph (glyph)
+  "Return character from `mood-line-glyph-alist' for GLYPH.
+
+If a character could not be found for the requested glyph, a fallback will be
+returned from `mood-line-glyphs-ascii'."
+  (char-to-string (or (alist-get glyph
+                                 mood-line-glyph-alist)
+                      (alist-get glyph
+                                 mood-line-glyphs-ascii))))
 
 (defun mood-line--string-trim-left (string)
   "Remove whitespace at the beginning of STRING."
@@ -185,104 +340,404 @@ The `Face' may be either a face symbol or a property list of key-value pairs
   (mood-line--string-trim-left (mood-line--string-trim-right string)))
 
 (defun mood-line--format (left right)
-  "Format a mode-line with a `LEFT' and `RIGHT' justified list of elements.
-The modeline should fit the `window-width' with space between the lists."
+  "Format a mode line with a `LEFT' and `RIGHT' justified list of elements.
+The mode line should fit the `window-width' with space between the lists."
   (let ((reserve (length right)))
     (concat left
             " "
             (propertize " "
-                        'display `((space :align-to (- right (- 0 right-margin) ,reserve))))
+                        'display `((space :align-to (- right
+                                                       (- 0 right-margin)
+                                                       ,reserve))))
             right)))
+
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Update functions
+;; Modal editing segment
 ;;
+;; -------------------------------------------------------------------------- ;;
 
-(defvar-local mood-line--vc-text nil)
-(defun mood-line--update-vc-segment (&rest _)
-  "Update `mood-line--vc-text' against the current VCS state."
-  (setq mood-line--vc-text
-        (when (and vc-mode buffer-file-name)
-          (let ((backend (vc-backend buffer-file-name))
-                (state (vc-state buffer-file-name (vc-backend buffer-file-name))))
-            (let ((face 'mode-line-neutral))
-              (concat (cond ((memq state '(edited added))
-                             (setq face 'mood-line-status-info)
-                             (propertize "+ " 'face face))
-                            ((eq state 'needs-merge)
-                             (setq face 'mood-line-status-warning)
-                             (propertize "⟷ " 'face face))
-                            ((eq state 'needs-update)
-                             (setq face 'mood-line-status-warning)
-                             (propertize "↑ " 'face face))
-                            ((memq state '(removed conflict unregistered))
-                             (setq face 'mood-line-status-error)
-                             (propertize "✖ " 'face face))
-                            (t
-                             (setq face 'mood-line-status-neutral)
-                             (propertize "✔ " 'face face)))
-                      (propertize (substring vc-mode (+ (if (eq backend 'Hg) 2 3) 2))
-                                  'face face
-                                  'mouse-face face)
-                      "  "))))))
+;; ---------------------------------- ;;
+;; Evil segment function
+;; ---------------------------------- ;;
 
-(defvar-local mood-line--flycheck-text nil)
-(defun mood-line--update-flycheck-segment (&optional status)
-  "Update `mood-line--flycheck-text' against the reported flycheck STATUS."
-  (setq mood-line--flycheck-text
-        (pcase status
-          ('finished (if flycheck-current-errors
-                         (let-alist (flycheck-count-errors flycheck-current-errors)
-                           (let ((sum (+ (or .error 0) (or .warning 0))))
-                             (propertize (concat "⚑ Issues: "
-                                                 (number-to-string sum)
-                                                 "  ")
-                                         'face (if .error
-                                                   'mood-line-status-error
-                                                 'mood-line-status-warning))))
-                       (propertize "✔ Good  " 'face 'mood-line-status-success)))
-          ('running (propertize "Δ Checking  " 'face 'mood-line-status-info))
-          ('errored (propertize "✖ Error  " 'face 'mood-line-status-error))
-          ('interrupted (propertize "⏸ Paused  " 'face 'mood-line-status-neutral))
-          ('no-checker ""))))
+(defun mood-line-segment-modal-evil ()
+  "Display the current evil-mode state."
+  (when (boundp 'evil-state)
+    (let ((mode-cons (alist-get evil-state mood-line-evil-state-alist)))
+      (concat (propertize (car mode-cons)
+                          'face (cdr mode-cons))
+              " "))))
 
+;; ---------------------------------- ;;
+;; Meow segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-modal-meow ()
+  "Display the current meow-mode state."
+  (when (boundp 'meow--current-state)
+    (let ((mode-cons (alist-get
+                      meow--current-state
+                      mood-line-meow-state-alist)))
+      (concat (propertize (car mode-cons)
+                          'face (cdr mode-cons))
+              " "))))
+
+;; ---------------------------------- ;;
+;; God segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-modal-god ()
+  "Indicate whether or not god-mode is active."
+  (if (bound-and-true-p god-local-mode)
+      '(:propertize "<G> "
+                    face (:inherit mood-line-status-warning))
+    "--- "))
+
+;; ---------------------------------- ;;
+;; Modal segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-modal ()
+  "Return the correct mode line segment for the first active modal mode found.
+
+Modal modes checked, in order: `evil-mode', `meow-mode', `god-mode'."
+  (cond
+   ((bound-and-true-p evil-mode)
+    (mood-line-segment-modal-evil))
+   ((bound-and-true-p meow-mode)
+    (mood-line-segment-modal-meow))
+   ((featurep 'god-mode)
+    (mood-line-segment-modal-god))))
+
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Segments
+;; Anzu segment
 ;;
-
-(defun mood-line-segment-modified ()
-  "Display an indicator for buffer modification status."
-  (if (not (string-match-p "\\*.*\\*" (buffer-name)))
-      (if (buffer-modified-p)
-          (propertize "● " 'face 'mood-line-modified)
-        (if (and buffer-read-only (buffer-file-name))
-            (propertize "■ " 'face 'mood-line-unimportant)
-          "  "))
-    "  "))
-
-(defun mood-line-segment-buffer-name ()
-  "Display the name of the current buffer."
-  (propertize "%b  " 'face 'mood-line-buffer-name))
+;; -------------------------------------------------------------------------- ;;
 
 (defun mood-line-segment-anzu ()
   "Display color-coded anzu status information."
-  (when (and (boundp 'anzu--state) anzu--state)
-    (cond ((eq anzu--state 'replace-query)
-           (format #("Replace×%d  " 7 10 (face mood-line-status-info)) anzu--cached-count))
-          (anzu--overflow-p
-           (format #("%d/%d+  " 0 2 (face mood-line-status-info) 3 6 (face mood-line-status-error)) anzu--current-position anzu--total-matched))
-          (t
-           (format #("%d/%d  " 0 2 (face mood-line-status-info)) anzu--current-position anzu--total-matched)))))
+  (when (bound-and-true-p anzu--state)
+    (cond
+     ((eq anzu--state 'replace-query)
+      (format #("Replace%s%d  "
+                7 10 (face mood-line-status-info))
+              (mood-line--get-glyph :count-separator)
+              anzu--cached-count))
+     (anzu--overflow-p
+      (format #("%d/%d+  "
+                0 2 (face mood-line-status-info)
+                3 6 (face mood-line-status-error))
+              anzu--current-position anzu--total-matched))
+     (t
+      (format #("%d/%d  "
+                0 2 (face mood-line-status-info))
+              anzu--current-position anzu--total-matched)))))
+
+;; -------------------------------------------------------------------------- ;;
+;;
+;; multiple-cursors segment
+;;
+;; -------------------------------------------------------------------------- ;;
 
 (defun mood-line-segment-multiple-cursors ()
   "Display the number of active multiple-cursors."
-  (when (and (boundp 'multiple-cursors-mode) multiple-cursors-mode)
-    (format #("MC×%d  " 2 5 (face mood-line-status-info)) (mc/num-cursors))))
+  (when (bound-and-true-p multiple-cursors-mode)
+    (format #("MC%s%d  "
+              2 5 (face mood-line-status-info))
+            (mood-line--get-glyph :count-separator)
+            (mc/num-cursors))))
 
-(defun mood-line-segment-position ()
+;; -------------------------------------------------------------------------- ;;
+;;
+;; VC segment
+;;
+;; -------------------------------------------------------------------------- ;;
+
+;; ---------------------------------- ;;
+;; Update function
+;; ---------------------------------- ;;
+
+(defvar-local mood-line--vc-text nil)
+
+(defun mood-line--vc-update-segment (&rest _)
+  "Update `mood-line--vc-text' against the current VCS state."
+  (setq mood-line--vc-text
+        (when (and vc-mode
+                   buffer-file-name)
+          (let* ((backend (vc-backend buffer-file-name))
+                 (branch (substring-no-properties vc-mode
+                                                  (+ (if (eq backend 'Hg) 2 3)
+                                                     2)))
+                 (state (vc-state buffer-file-name
+                                  (vc-backend buffer-file-name)))
+                 (face 'mood-line-status-neutral)
+                 (glyph :vc-good))
+            (cond
+             ((memq state '(edited added))
+              (setq face 'mood-line-status-info
+                    glyph :vc-added))
+             ((eq state 'needs-merge)
+              (setq face 'mood-line-status-warning
+                    glyph :vc-needs-merge))
+             ((eq state 'needs-update)
+              (setq face 'mood-line-status-warning
+                    glyph :vc-needs-update))
+             ((memq state '(removed conflict unregistered))
+              (setq face 'mood-line-status-error
+                    glyph :vc-conflict))
+             (t
+              (setq face 'mood-line-status-neutral
+                    glyph :vc-good)))
+            (propertize (concat (mood-line--get-glyph glyph)
+                                " "
+                                branch
+                                "  ")
+                        'face face)))))
+
+;; ---------------------------------- ;;
+;; Segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-vc ()
+  "Display color-coded version control information."
+  mood-line--vc-text)
+
+;; -------------------------------------------------------------------------- ;;
+;;
+;; Checker segment
+;;
+;; -------------------------------------------------------------------------- ;;
+
+;; ---------------------------------- ;;
+;; Flycheck update function
+;; ---------------------------------- ;;
+
+(defvar-local mood-line--checker-flycheck-text nil)
+
+(defun mood-line--checker-flycheck-count-errors ()
+  "Return alist with count of all error types in `flycheck-current-errors'.
+
+Counts will be returned in an alist as the `cdr' of the following keys:
+`'info-count'    | All notes reported by checker
+`'error-count'   | All errors reported by checker
+`'warning-count' | All warnings reported by checker
+`'issues-count'  | All errors and warnings reported by checker
+`'all-count'     | Everything reported by checker"
+  (let-alist (flycheck-count-errors flycheck-current-errors)
+    (let ((info-count (+ (or .info 0)))
+          (error-count (+ (or .error 0)))
+          (warning-count (+ (or .warning 0))))
+      `((info-count . ,info-count)
+        (error-count . ,error-count)
+        (warning-count . ,warning-count)
+        (issues-count . ,(+ warning-count
+                            error-count))
+        (all-count . ,(+ info-count
+                         warning-count
+                         error-count))))))
+
+(defun mood-line--checker-flycheck-update-segment (&optional status)
+  "Update `mood-line--checker-flycheck-text' against provided flycheck STATUS."
+  (setq mood-line--checker-flycheck-text
+        (pcase status
+          ('finished
+           (let-alist (mood-line--checker-flycheck-count-errors)
+             (cond
+              ((> .error-count 0)
+               (propertize (concat (mood-line--get-glyph :checker-issues)
+                                   " Errors: "
+                                   (number-to-string .all-count)
+                                   "  ")
+                           'face 'mood-line-status-error))
+              ((> .warning-count 0)
+               (propertize (concat (mood-line--get-glyph :checker-issues)
+                                   " Issues: "
+                                   (number-to-string .all-count)
+                                   "  ")
+                           'face 'mood-line-status-warning))
+              ((> .info-count 0)
+               (propertize (concat (mood-line--get-glyph :checker-info)
+                                   " Info: "
+                                   (number-to-string .all-count)
+                                   "  ")
+                           'face 'mood-line-status-info))
+              ((zerop .all-count)
+               (propertize (concat (mood-line--get-glyph :checker-good)
+                                   " Good  ")
+                           'face 'mood-line-status-success)))))
+          ('running
+           (propertize (concat (mood-line--get-glyph :checker-checking)
+                               " Checking  ")
+                       'face 'mood-line-status-info))
+          ('errored
+           (propertize (concat (mood-line--get-glyph :checker-errored)
+                               " Error  ")
+                       'face 'mood-line-status-error))
+          ('interrupted
+           (propertize (concat (mood-line--get-glyph :checker-interrupted)
+                               " Paused  ")
+                       'face 'mood-line-status-neutral))
+          ('no-checker ""))))
+
+;; ---------------------------------- ;;
+;; Flycheck segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-checker-flycheck ()
+  "Display the current status of flycheck."
+  mood-line--checker-flycheck-text)
+
+;; ---------------------------------- ;;
+;; Flymake update function
+;; ---------------------------------- ;;
+
+(defvar-local mood-line--checker-flymake-text nil)
+
+(defun mood-line--checker-flymake-count-report-type (type)
+  "Return count of current flymake reports of TYPE."
+  (let ((count 0))
+    (dolist (d (flymake-diagnostics))
+      (when (eq (cl-struct-slot-value 'flymake--diag 'type d) type)
+        (cl-incf count)))
+    count))
+
+(defun mood-line--checker-flymake-count-errors ()
+  "Return alist with count of all current flymake diagnostic reports.
+
+Counts will be returned in an alist as the cdr of the following keys:
+`'info-count'    | All notes reported by checker
+`'error-count'   | All errors reported by checker
+`'warning-count' | All warnings reported by checkero
+`'issues-count'  | All errors and warnings reported by checker
+`'all-count'     | Everything reported by checker"
+  (let ((info-count (mood-line--checker-flymake-count-report-type :note))
+        (error-count (mood-line--checker-flymake-count-report-type :error))
+        (warning-count (mood-line--checker-flymake-count-report-type :warning)))
+    `((info-count . ,info-count)
+      (error-count . ,error-count)
+      (warning-count . ,warning-count)
+      (issues-count . ,(+ warning-count
+                          error-count))
+      (all-count . ,(+ info-count
+                       warning-count
+                       error-count)))))
+
+(defun mood-line--checker-flymake-update-segment (&rest _)
+  "Update `mood-line--checker-flymake-text' against the state of flymake."
+  (setq mood-line--checker-flymake-text
+        (when (and (fboundp 'flymake-is-running)
+                   (flymake-is-running))
+          (let-alist (mood-line--checker-flymake-count-errors)
+            (cond
+             ((seq-difference (flymake-running-backends)
+                              (flymake-reporting-backends))
+              (propertize (concat (mood-line--get-glyph :checker-checking)
+                                  " Checking  ")
+                          'face 'mood-line-status-info))
+             ((> .error-count 0)
+              (propertize (concat (mood-line--get-glyph :checker-issues)
+                                  " Errors: "
+                                  (number-to-string .all-count)
+                                  "  ")
+                          'face 'mood-line-status-error))
+             ((> .warning-count 0)
+              (propertize (concat (mood-line--get-glyph :checker-issues)
+                                  " Issues: "
+                                  (number-to-string .all-count)
+                                  "  ")
+                          'face 'mood-line-status-warning))
+             ((> .info-count 0)
+              (propertize (concat (mood-line--get-glyph :checker-info)
+                                  " Info: "
+                                  (number-to-string .all-count)
+                                  "  ")
+                          'face 'mood-line-status-info))
+             (t
+              (propertize (concat (mood-line--get-glyph :checker-good)
+                                  " Good  ")
+                          'face 'mood-line-status-success)))))))
+
+;; ---------------------------------- ;;
+;; Flymake segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-checker-flymake ()
+  "Display the current status of flymake."
+  mood-line--checker-flymake-text)
+
+;; ---------------------------------- ;;
+;; Checker segment function
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-checker ()
+  "Return the correct mode line segment for the first active checker found.
+
+Checkers checked, in order: `flycheck', `flymake'."
+  (cond
+   ((bound-and-true-p flycheck-mode)
+    (mood-line-segment-checker-flycheck))
+   ((bound-and-true-p flymake-mode)
+    (mood-line-segment-checker-flymake))))
+
+;; -------------------------------------------------------------------------- ;;
+;;
+;; Buffer information segments
+;;
+;; -------------------------------------------------------------------------- ;;
+
+;; ---------------------------------- ;;
+;; Buffer status segment
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-buffer-status ()
+  "Return an indicator for buffer status."
+  (if (buffer-file-name)
+      (concat (cond
+               ((and (buffer-modified-p)
+                     (buffer-narrowed-p))
+                (propertize (mood-line--get-glyph :buffer-narrowed)
+                            'face 'mood-line-modified))
+               ((buffer-modified-p)
+                (propertize (mood-line--get-glyph :buffer-modified)
+                            'face 'mood-line-modified))
+               ((or buffer-read-only
+                    (buffer-narrowed-p))
+                (propertize (mood-line--get-glyph :buffer-narrowed)
+                            'face 'mood-line-unimportant))
+               (buffer-read-only
+                (propertize (mood-line--get-glyph :buffer-read-only)
+                            'face 'mood-line-unimportant))
+               (t " "))
+              " ")
+    "  "))
+
+;; ---------------------------------- ;;
+;; Buffer name segment
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-buffer-name ()
+  "Display the name of the current buffer."
+  (propertize "%b  "
+              'face 'mood-line-buffer-name))
+
+;; ---------------------------------- ;;
+;; Cursor position segment
+;; ---------------------------------- ;;
+
+(defun mood-line-segment-cursor-position ()
   "Display the current cursor position."
   (concat "%l:%c"
-          (when mood-line-show-cursor-point (propertize (format ":%d" (point)) 'face 'mood-line-unimportant))
-          (propertize " %p%%  " 'face 'mood-line-unimportant)))
+          (when mood-line-show-cursor-point
+            (propertize (format ":%d" (point))
+                        'face 'mood-line-unimportant))
+          (propertize " %p%%  "
+                      'face 'mood-line-unimportant)))
+
+;; ---------------------------------- ;;
+;; EOL segment
+;; ---------------------------------- ;;
 
 (defun mood-line-segment-eol ()
   "Display the EOL style of the current buffer."
@@ -292,83 +747,156 @@ The modeline should fit the `window-width' with space between the lists."
       (1 "CRLF  ")
       (2 "CR  "))))
 
+;; ---------------------------------- ;;
+;; Encoding segment
+;; ---------------------------------- ;;
+
 (defun mood-line-segment-encoding ()
   "Display the encoding and EOL style of the buffer."
   (when mood-line-show-encoding-information
     (concat (let ((sys (coding-system-plist buffer-file-coding-system)))
-              (cond ((memq (plist-get sys :category) '(coding-category-undecided coding-category-utf-8))
-                     "UTF-8")
-                    (t (upcase (symbol-name (plist-get sys :name))))))
+              (cond
+               ((memq (plist-get sys :category)
+                      '(coding-category-undecided coding-category-utf-8))
+                "UTF-8")
+               (t
+                (upcase (symbol-name (plist-get sys :name))))))
             "  ")))
 
-(defun mood-line-segment-vc ()
-  "Display color-coded version control information."
-  mood-line--vc-text)
+;; ---------------------------------- ;;
+;; Major mode segment
+;; ---------------------------------- ;;
 
 (defun mood-line-segment-major-mode ()
-  "Display the current major mode."
-  (concat (format-mode-line mode-name 'mood-line-major-mode) "  "))
+  "Display the name of the current major mode."
+  (concat (propertize (substring-no-properties (format-mode-line mode-name))
+                      'face 'mood-line-major-mode)
+          "  "))
+
+;; ---------------------------------- ;;
+;; Misc. info segment
+;; ---------------------------------- ;;
 
 (defun mood-line-segment-misc-info ()
   "Display the current value of `mode-line-misc-info'."
-  (let ((misc-info (format-mode-line mode-line-misc-info 'mood-line-unimportant)))
-    (unless (string= (mood-line--string-trim misc-info) "")
-      (concat (mood-line--string-trim misc-info) "  "))))
+  (let ((misc-info (format-mode-line mode-line-misc-info)))
+    (unless (string-blank-p misc-info)
+      (concat (propertize (mood-line--string-trim misc-info)
+                          'face 'mood-line-unimportant)
+              "  "))))
 
-(defun mood-line-segment-flycheck ()
-  "Display color-coded flycheck information."
-  mood-line--flycheck-text)
-
-(defun mood-line-segment-flymake ()
-  "Display information about the current status of flymake."
-  (when (and (boundp 'flymake-mode) flymake-mode)
-    ;; Depending on Emacs version, flymake stores the mode-line segment
-    ;; using one of two variable names
-    (let ((flymake-segment-format (if (boundp 'flymake-mode-line-format)
-                                      flymake-mode-line-format
-                                    flymake--mode-line-format)))
-      (concat (mood-line--string-trim (format-mode-line flymake-segment-format)) "  "))))
+;; ---------------------------------- ;;
+;; Process segment
+;; ---------------------------------- ;;
 
 (defun mood-line-segment-process ()
   "Display the current value of `mode-line-process'."
   (let ((process-info (format-mode-line mode-line-process)))
-    (unless (string= (mood-line--string-trim process-info) "")
-      (concat (mood-line--string-trim process-info) "  "))))
-
-(defun mood-line-segment-evil ()
-  "Display the current evil-mode state."
-  (when (boundp 'evil-state)
-    (let ((mode-cons (alist-get evil-state mood-line-evil-state-alist)))
-      (concat (propertize (car mode-cons) 'face (cdr mode-cons)) " "))))
-
-(defun mood-line-segment-meow ()
-  "Display the current meow-mode state."
-  (when (boundp 'meow--current-state)
-    (let ((mode-cons (alist-get
-                      meow--current-state
-                      mood-line-meow-state-alist)))
-      (concat (propertize (car mode-cons) 'face (cdr mode-cons)) " "))))
-
-(defun mood-line-segment-god ()
-  "Indicate whether or not god-mode is active."
-  (if (bound-and-true-p god-local-mode)
-      '(:propertize "<G> "
-                    face (:inherit mood-line-status-warning))
-    "--- "))
-
-(defun mood-line-segment-modal ()
-  "Call the correct mode-line segment when the first modal-mode is found."
-  (cond ((bound-and-true-p evil-mode) (mood-line-segment-evil))
-        ((bound-and-true-p meow-mode) (mood-line-segment-meow))
-        ((featurep 'god-mode) (mood-line-segment-god))))
+    (unless (string-blank-p process-info)
+      (concat (mood-line--string-trim process-info)
+              "  "))))
 
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Activation function
+;; mood-line-mode definition
 ;;
+;; -------------------------------------------------------------------------- ;;
 
 (defvar-local mood-line--default-mode-line mode-line-format)
 (defvar-local mood-line--anzu-cons-mode-line-p nil)
 
+;; ---------------------------------- ;;
+;; Activation function
+;; ---------------------------------- ;;
+
+(defun mood-line--activate ()
+  "Activate mood-line, installing hooks and setting `mode-line-format'."
+
+  ;; Set up flycheck hooks
+  (add-hook 'flycheck-status-changed-functions
+            #'mood-line--checker-flycheck-update-segment)
+  (add-hook 'flycheck-mode-hook
+            #'mood-line--checker-flycheck-update-segment)
+
+  ;; Set up flymake hooks
+  (advice-add 'flymake-start :after
+              #'mood-line--checker-flymake-update-segment)
+  (advice-add 'flymake--handle-report :after
+              #'mood-line--checker-flymake-update-segment)
+
+  ;; Set up VC hooks
+  (add-hook 'find-file-hook
+            #'mood-line--vc-update-segment)
+  (add-hook 'after-save-hook
+            #'mood-line--vc-update-segment)
+  (advice-add 'vc-refresh-state :after
+              #'mood-line--vc-update-segment)
+
+  ;; Disable anzu's mode line segment setting, saving the previous
+  ;; setting to be restored later (if present)
+  (when (boundp 'anzu-cons-mode-line-p)
+    (setq mood-line--anzu-cons-mode-line-p anzu-cons-mode-line-p))
+  (setq-default anzu-cons-mode-line-p nil)
+
+  ;; Save previous value of `mode-line-format' to be restored later
+  (setq mood-line--default-mode-line mode-line-format)
+
+  ;; Set new value of `mode-line-format'
+  (setq-default mode-line-format
+                '((:eval
+                   (mood-line--format
+                    ;; Left
+                    (format-mode-line
+                     '(" "
+                       (:eval (mood-line-segment-modal))
+                       (:eval (mood-line-segment-buffer-status))
+                       (:eval (mood-line-segment-buffer-name))
+                       (:eval (mood-line-segment-anzu))
+                       (:eval (mood-line-segment-multiple-cursors))
+                       (:eval (mood-line-segment-cursor-position))))
+
+                    ;; Right
+                    (format-mode-line
+                     '((:eval (mood-line-segment-eol))
+                       (:eval (mood-line-segment-encoding))
+                       (:eval (mood-line-segment-vc))
+                       (:eval (mood-line-segment-major-mode))
+                       (:eval (mood-line-segment-misc-info))
+                       (:eval (mood-line-segment-checker))
+                       (:eval (mood-line-segment-process))
+                       " ")))))))
+
+;; ---------------------------------- ;;
+;; Deactivation function
+;; ---------------------------------- ;;
+
+(defun mood-line--deactivate ()
+  "Deactivate mood-line, uninstalling hooks and restoring `mode-line-format'."
+
+  ;; Remove flycheck hooks
+  (remove-hook 'flycheck-status-changed-functions
+               #'mood-line--checker-flycheck-update-segment)
+  (remove-hook 'flycheck-mode-hook
+               #'mood-line--checker-flycheck-update-segment)
+
+  ;; Remove VC hooks
+  (remove-hook 'file-find-hook
+               #'mood-line--vc-update-segment)
+  (remove-hook 'after-save-hook
+               #'mood-line--vc-update-segment)
+  (advice-remove #'vc-refresh-state
+                 #'mood-line--vc-update-segment)
+
+  ;; Restore anzu's mode line segment setting
+  (setq-default anzu-cons-mode-line-p mood-line--anzu-cons-mode-line-p)
+
+  ;; Restore the original value of `mode-line-format'
+  (setq-default mode-line-format mood-line--default-mode-line))
+
+;; ---------------------------------- ;;
+;; Mode definition
+;; ---------------------------------- ;;
+
 ;;;###autoload
 (define-minor-mode mood-line-mode
   "Toggle mood-line on or off."
@@ -376,71 +904,14 @@ The modeline should fit the `window-width' with space between the lists."
   :global t
   :lighter nil
   (if mood-line-mode
-      (progn
-
-        ;; Setup flycheck hooks
-        (add-hook 'flycheck-status-changed-functions #'mood-line--update-flycheck-segment)
-        (add-hook 'flycheck-mode-hook #'mood-line--update-flycheck-segment)
-
-        ;; Setup VC hooks
-        (add-hook 'find-file-hook #'mood-line--update-vc-segment)
-        (add-hook 'after-save-hook #'mood-line--update-vc-segment)
-        (advice-add #'vc-refresh-state :after #'mood-line--update-vc-segment)
-
-        ;; Disable anzu's mode-line segment setting, saving the previous
-        ;; setting to be restored later (if present)
-        (when (boundp 'anzu-cons-mode-line-p)
-          (setq mood-line--anzu-cons-mode-line-p anzu-cons-mode-line-p))
-        (setq-default anzu-cons-mode-line-p nil)
-
-        ;; Save previous mode-line-format to be restored later
-        (setq mood-line--default-mode-line mode-line-format)
-
-        ;; Set the new mode-line-format
-        (setq-default mode-line-format
-                      '((:eval
-                         (mood-line--format
-                          ;; Left
-                          (format-mode-line
-                           '(" "
-                             (:eval (mood-line-segment-modal))
-                             (:eval (mood-line-segment-modified))
-                             (:eval (mood-line-segment-buffer-name))
-                             (:eval (mood-line-segment-anzu))
-                             (:eval (mood-line-segment-multiple-cursors))
-                             (:eval (mood-line-segment-position))))
-
-                          ;; Right
-                          (format-mode-line
-                           '((:eval (mood-line-segment-eol))
-                             (:eval (mood-line-segment-encoding))
-                             (:eval (mood-line-segment-vc))
-                             (:eval (mood-line-segment-major-mode))
-                             (:eval (mood-line-segment-misc-info))
-                             (:eval (mood-line-segment-flycheck))
-                             (:eval (mood-line-segment-flymake))
-                             (:eval (mood-line-segment-process))
-                             " ")))))))
-    (progn
-
-      ;; Remove flycheck hooks
-      (remove-hook 'flycheck-status-changed-functions #'mood-line--update-flycheck-segment)
-      (remove-hook 'flycheck-mode-hook #'mood-line--update-flycheck-segment)
-
-      ;; Remove VC hooks
-      (remove-hook 'file-find-hook #'mood-line--update-vc-segment)
-      (remove-hook 'after-save-hook #'mood-line--update-vc-segment)
-      (advice-remove #'vc-refresh-state #'mood-line--update-vc-segment)
-
-      ;; Restore anzu's mode-line segment setting
-      (setq-default anzu-cons-mode-line-p mood-line--anzu-cons-mode-line-p)
-
-      ;; Restore the original mode-line format
-      (setq-default mode-line-format mood-line--default-mode-line))))
+      (mood-line--activate)
+    (mood-line--deactivate)))
 
+;; -------------------------------------------------------------------------- ;;
 ;;
-;; Provide mood-line
+;; Provide package
 ;;
+;; -------------------------------------------------------------------------- ;;
 
 (provide 'mood-line)