(Emacs/elisp|config)+new package that generates a mode-line

Using left, centre and right segments generates a mode line with
padded strings that actually achieves this.

Emacs/.config/emacs/elisp/better-mode-line.el

@@ -0,0 +1,89 @@
+;;; better-mode-line.el --- A better mode-line system designed by me  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2024  Aryadev Chavali
+
+;; Author: Aryadev Chavali <aryadev@aryadevchavali.com>
+;; Keywords:
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; There are 3 lists for the left, centre and right of the mode-line.  They're
+;; the same as mode-line-format in terms of general schema as they're fed
+;; directly into that variable.  Padding strings are automatically generated
+;; based on these segments so be sure to set these.
+
+;;; Code:
+
+(defun +better-mode-line/evil-state ()
+  "Returns either the empty string if no evil-state is defined or
+the first character of the evil state capitalised"
+  (with-eval-after-load "evil"
+    (if (bound-and-true-p evil-state)
+        (upcase
+         (substring
+	        (format "%s"
+			            evil-state)
+          0 1))
+      "")))
+
+(defvar +better-mode-line/left-segment nil
+  "List of elements that are placed on the left of the mode-line")
+
+(defvar +better-mode-line/centre-segment nil
+  "List of elements that should be on the centre of the mode-line")
+
+(defvar +better-mode-line/right-segment nil
+  "List of elements that should be on the right of the mode-line")
+
+(defconst +better-mode-line/--minimum-padding 4
+  "Minimum size of padding string.")
+
+(defun +better-mode-line/--left->centre-padding ()
+  "Returns a string which pads the centre segment perfectly relative
+to the left segment."
+  (let* ((left-segment-size (length (format-mode-line +better-mode-line/left-segment)))
+         (centre-segment-size (length (format-mode-line +better-mode-line/centre-segment)))
+         (padding-size (- (/ (window-width) 2) (/ centre-segment-size 2) left-segment-size)))
+    (make-string (if (< padding-size +better-mode-line/--minimum-padding)
+                     +better-mode-line/--minimum-padding
+                   padding-size)
+                 ?\s)))
+
+(defun +better-mode-line/--centre->right-padding ()
+  "Returns a string which pads the right segment perfectly relative
+to the centre segment"
+  (let* ((centre-segment-size (length (format-mode-line +better-mode-line/centre-segment)))
+         (right-segment-size (length (format-mode-line +better-mode-line/right-segment)))
+         (padding-size (- (/ (window-width) 2) (/ centre-segment-size 2) right-segment-size)))
+    (make-string (if (< padding-size +better-mode-line/--minimum-padding)
+                     +better-mode-line/--minimum-padding
+                   padding-size)
+                 ?\s)))
+
+
+(defun +better-mode-line/setup-mode-line ()
+  "Call this to setup the mode-line when:
+- first loading the package.
+- segments are updated."
+  (setq-default mode-line-format
+                `(,@+better-mode-line/left-segment
+                  (:eval (+better-mode-line/--left->centre-padding))
+                  ,@+better-mode-line/centre-segment
+                  (:eval (+better-mode-line/--centre->right-padding))
+                  ,@+better-mode-line/right-segment)))
+
+(provide 'better-mode-line)
+;;; better-mode-line.el ends here