From f4fcca122bbceded903ca26218add39f14a13fa8 Mon Sep 17 00:00:00 2001
From: hippoz <10706925-hippoz@users.noreply.gitlab.com>
Date: Wed, 24 May 2023 22:59:25 +0300
Subject: [PATCH] allow for centering on box layout

---
 src/box-layout-node.c | 12 ++++++++++--
 src/box-layout-node.h |  6 ++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/box-layout-node.c b/src/box-layout-node.c
index 7b6dbc9..513c736 100644
--- a/src/box-layout-node.c
+++ b/src/box-layout-node.c
@@ -118,7 +118,11 @@ int box_layout_handle(UINode *component, enum UIEvent ev, size_t d, void *p)
                     x += gap;
                 }
                 current->rect.x = x;
-                current->rect.y = y;
+                if (box_layout_node->justify_secondary_dimension == UI_BOX_LAYOUT_JUSTIFY_CENTER) {
+                    current->rect.y = margin_top + (maximum_secondary_position - current->rect.h) / 2;
+                } else {
+                    current->rect.y = y;
+                }
                 x += current->rect.w;
             } else {
                 if (current->height_policy == UI_SIZE_POLICY_GROW) {
@@ -130,7 +134,11 @@ int box_layout_handle(UINode *component, enum UIEvent ev, size_t d, void *p)
                 if (current_index) {
                     y += gap;
                 }
-                current->rect.x = x;
+                if (box_layout_node->justify_secondary_dimension == UI_BOX_LAYOUT_JUSTIFY_CENTER) {
+                    current->rect.x = margin_left + (maximum_secondary_position - current->rect.w) / 2;
+                } else {
+                    current->rect.x = x;
+                }
                 current->rect.y = y;
                 y += current->rect.h;
             }
diff --git a/src/box-layout-node.h b/src/box-layout-node.h
index 078f409..a8fc793 100644
--- a/src/box-layout-node.h
+++ b/src/box-layout-node.h
@@ -3,9 +3,15 @@
 
 #include "node.h"
 
+enum UIBoxLayoutJustify {
+    UI_BOX_LAYOUT_JUSTIFY_START,
+    UI_BOX_LAYOUT_JUSTIFY_CENTER
+};
+
 typedef struct UIBoxLayoutNode {
     UINode node;
     enum UIDirection direction;
+    enum UIBoxLayoutJustify justify_secondary_dimension;
     double margin_top, margin_left, margin_bottom, margin_right, gap;
 } UIBoxLayoutNode;