From 3c794e59c871927c0e84254a35c0e49ff1e9d287 Mon Sep 17 00:00:00 2001
From: Jakub <birdt@citadel.tail9cfa84.ts.net>
Date: Sat, 1 Nov 2025 20:19:23 +0800
Subject: [PATCH] Initial commit

---
 README.org     |  5 +++
 jomini-mode.el | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 88 insertions(+)
 create mode 100644 README.org
 create mode 100644 jomini-mode.el

diff --git a/README.org b/README.org
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+#+title: jomini-mode.el
+
+Extremely basic major mode for editing Jomini script files. Needs work, but it handles all the basics like indentation properly which is all I really care about currently.
+
+It won't automatically detect what files it should start in currently. That is left as an exercise for the reader.
diff --git a/jomini-mode.el b/jomini-mode.el
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+;;; jomini-mode.el --- Major mode for jomini script editing an Clausewitz paradox modding. -*- lexical-binding: t -*-
+
+;; This file is not part of GNU Emacs
+
+;; 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:
+
+;; Mostly copied from https://www.omarpolo.com/post/writing-a-major-mode.html
+
+;;; Code:
+
+(require 'rx)
+
+(defconst jomini/font-lock-defaults
+  (let ((keywords '("root" "prev" "this" "limit" "trigger" "count"))
+	(logops '("AND" "OR" "NOT" "NOR" "NAND"))
+	(statements '("if" "else_if" "else" "switch" "while" "trigger_if" "trigger_else_if" "trigger_else")))
+    `(((,(rx-to-string `(: (or ,@keywords))) 0 font-lock-keyword-face)
+       (,(rx-to-string '(: (one-or-more word) ":")) 0 font-lock-type-face)
+       (,(rx-to-string '(: "#" (zero-or-more not-newline) "\n")))
+       (,(rx-to-string `(or (: "$" (one-or-more word) "$") (: (or ,@logops)))) 0 font-lock-variable-name-face)
+       (,(rx-to-string `(: (or ,@statements))) 0 font-lock-function-call-face)))))
+
+(defvar jomini-mode-syntax-table
+  (let ((st (make-syntax-table)))
+    ;; Paren joining
+    (modify-syntax-entry ?\{ "(}" st)
+    (modify-syntax-entry ?\} "){" st)
+
+    ;; Underscores can make up words
+    (modify-syntax-entry ?_ "w" st)
+    
+    ;; Comments
+    (modify-syntax-entry ?\# "<" st)
+    (modify-syntax-entry ?\n ">" st)
+    
+    st))
+
+(defun jomini-indent-line ()
+  "Indent the current line."
+  (let (indent
+	boi-p
+	move-eol-p
+	(point (point)))
+    (save-excursion
+      (back-to-indentation)
+      (setq indent (car (syntax-ppss))
+	    boi-p (= point (point)))
+      (when boi-p
+	(setq move-eol-p t))
+      (when (eq (char-after) ?\})
+	(setq indent (1- indent)))
+      (delete-region (line-beginning-position)
+		     (point))
+      (indent-to (* tab-width indent)))
+    (when move-eol-p
+      (move-end-of-line nil))))
+
+(define-derived-mode jomini-mode prog-mode "jmni"
+  "Major mode for Jomini modding."
+  :syntax-table jomini-mode-syntax-table
+  (setq font-lock-defaults jomini/font-lock-defaults)
+  (setq-local comment-start "#")
+  (setq-local comment-start-skip "#+[\t ]*")
+  (setq-local indent-line-function #'jomini-indent-line)
+  (setq-local indent-tabs-mode t))
+
+(provide 'jomini-mode)
+
+;;; jomini-mode.el ends here