From a89183c8c8097e5b54a130b4c1ddbd07c89cde2d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jonas=20R=C3=B6ger?= <jonas.roeger@tu-dortmund.de>
Date: Mon, 28 Oct 2024 22:44:17 +0100
Subject: [PATCH] Home Gen390 @ 2024-10-28-22:44

---
 modules/home/doom/doom.nix                    |  3 ++
 modules/home/doom/static/config.el            |  2 +
 .../doom/static/packages/treesit-docgen.el    | 50 +++++++++++++++++++
 3 files changed, 55 insertions(+)
 create mode 100644 modules/home/doom/static/packages/treesit-docgen.el

diff --git a/modules/home/doom/doom.nix b/modules/home/doom/doom.nix
index de909f9..e95a118 100644
--- a/modules/home/doom/doom.nix
+++ b/modules/home/doom/doom.nix
@@ -118,6 +118,9 @@ in {
       "doom-config/config.el" = {
         source = ./static/config.el;
       };
+      "doom-config/packages/treesit-docgen.el" = {
+        source = ./static/packages/treesit-docgen.el;
+      };
       "doom-config/init.el" = {
         source = ./static/init.el;
         onChange = "${doom-setup} sync --force -e";
diff --git a/modules/home/doom/static/config.el b/modules/home/doom/static/config.el
index b95ef95..dde5c16 100644
--- a/modules/home/doom/static/config.el
+++ b/modules/home/doom/static/config.el
@@ -151,6 +151,7 @@
 
 ;;Use TS-modes
 (after! treesit
+  (load! "packages/treesit-docgen.el")
   (setq treesit-font-lock-level 4))
 
 (defconst mode-ts-mode-mapping
@@ -194,6 +195,7 @@
 
 ;; Integrate with legacy tree-sitter mode
 (after! tree-sitter
+  (add-hook! 'c++-ts-mode-hook #'tree-sitter-mode)
   (add-hook! 'tree-sitter-mode-hook #'tree-sitter-hl-mode)
   (dolist (mapping tree-sitter-major-mode-language-alist)
     (let* ((pre-mode (car mapping))
diff --git a/modules/home/doom/static/packages/treesit-docgen.el b/modules/home/doom/static/packages/treesit-docgen.el
new file mode 100644
index 0000000..121704e
--- /dev/null
+++ b/modules/home/doom/static/packages/treesit-docgen.el
@@ -0,0 +1,50 @@
+(defun treesit-docgen--get-function-node (node)
+  "Get the function node the given NODE belongs to. Or nil"
+  (treesit-parent-until node
+                        (lambda (n)
+                          (or (equal (treesit-node-type n) "function_definition")
+                              (and (equal (treesit-node-type n) "declaration"))
+                              (equal (treesit-node-type (treesit-node-child-by-field-name n "declarator"))
+                                     "function_declarator")))
+                        t)
+  )
+
+(defun treesit-docgen--fn-template-node (fn-node)
+  "Get the template node of a function or nil"
+  (let* ((par (treesit-node-parent fn-node))
+         (par-t (treesit-node-type par)))
+    (when (string= par-t "template_declaration") par)
+    ))
+
+(defun treesit-docgen--fn-tpars (fn-node)
+  "Get the template parameters of the function node or nil"
+  (let* ((template (treesit-docgen--fn-template-node fn-node))
+         (tpars (treesit-node-child-by-field-name template "parameters")))
+    (when tpars
+      (mapcar (lambda (tpar) (treesit-node-text tpar)) (treesit-node-children tpars)))
+    ))
+
+(defun treesit-docgen--fn-type (fn-node)
+  "Get the return type of the function node"
+  (let ((fn-type-node (treesit-node-child-by-field-name fn-node "type")))
+    (treesit-node-text fn-type-node)))
+
+(defun treesit-docgen--fn-pars (fn-node)
+  "Get the parameter names of the function node"
+  (let* ((fn-node-decl (treesit-node-child-by-field-name fn-node "declarator"))
+         (fn-node-pars (treesit-node-child-by-field-name fn-node-decl "parameters"))
+         )
+    (mapcar (lambda (par) (treesit-node-text par)) (treesit-node-children fn-node-pars))))
+
+(defun treesit-docgen-insert-doc ()
+  "Insert a documentation template for the function at point"
+  (interactive)
+  (let* ((node (treesit-node-at (point)))
+         (fn-node (treesit-docgen--get-function-node node))
+         )
+    (when fn-node
+      (message "FN-Type: %s, FN-Pars: %s, FN-TPars: %s"
+               (or (treesit-docgen--fn-type fn-node) "none")
+               (or (treesit-docgen--fn-pars fn-node) "none")
+               (or (treesit-docgen--fn-tpars fn-node) "none")
+               ))))