From bf34c92e09e84a5eb2d7823f849eda91effe9729 Mon Sep 17 00:00:00 2001
From: Raimon Zamora <jaildoctor@gmail.com>
Date: Wed, 18 Mar 2026 10:33:02 +0100
Subject: [PATCH] =?UTF-8?q?VERSI=C3=93=201.4.5=20-=20[NEW]=20Afegida=20fun?=
 =?UTF-8?q?ci=C3=B3=20"sub"=20al=20modul=20estandar=20"utf8"?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 lua.cpp            | 47 ++++++++++++++++++++++++++++++++++++++++++++++
 version.h          |  2 +-
 vscode/library.lua | 10 ++++++++++
 3 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/lua.cpp b/lua.cpp
index 5e28d2d..cae9c5c 100644
--- a/lua.cpp
+++ b/lua.cpp
@@ -993,8 +993,50 @@ extern "C" {
         return 1;
     }
 
+    static int cpp_utf8_sub(lua_State *L) {
+        size_t slen;
+        const char *s = luaL_checklstring(L, 1, &slen);
+        int i = luaL_checkinteger(L, 2);
+        int j = luaL_optinteger(L, 3, -1);
+
+        // Get utf8.offset
+        lua_getglobal(L, "utf8");
+        lua_getfield(L, -1, "offset");
+
+        // Compute start byte index
+        lua_pushvalue(L, 1);       // string
+        lua_pushinteger(L, i);     // start index
+        lua_call(L, 2, 1);         // utf8.offset(s, i)
+        lua_Integer start = lua_tointeger(L, -1);
+        lua_pop(L, 1);
+
+        if (start == 0) {
+            lua_pushliteral(L, "");
+            lua_pop(L, 1);         // pop utf8 table
+            return 1;
+        }
+
+        // Compute end byte index (j+1)
+        lua_getfield(L, -1, "offset");
+        lua_pushvalue(L, 1);
+        lua_pushinteger(L, j + 1);
+        lua_call(L, 2, 1);
+        lua_Integer end = lua_tointeger(L, -1);
+        lua_pop(L, 2);             // pop result + utf8 table
+
+        if (end == 0) {
+            // until end of string
+            lua_pushlstring(L, s + start - 1, slen - (start - 1));
+            return 1;
+        }
+
+        lua_pushlstring(L, s + start - 1, (end - 1) - (start - 1));
+        return 1;
+    }
+
 }
 
+
 lua_State *L;
 bool is_playing = false;
 bool init_exists = false;
@@ -1293,6 +1335,11 @@ void push_lua_funcs() {
 
     lua_setglobal(L, "pad");
 
+    
+    lua_getglobal(L, "utf8");                // push utf8 table
+    lua_pushcfunction(L, cpp_utf8_sub);      // push C function
+    lua_setfield(L, -2, "sub");              // utf8.sub = cpp_utf8_sub
+    lua_pop(L, 1);                           // pop utf8 table
 }
 
 /*
diff --git a/version.h b/version.h
index a983b99..2c93adf 100644
--- a/version.h
+++ b/version.h
@@ -1,3 +1,3 @@
 #pragma once
 
-#define MINI_VERSION "1.4.4"
+#define MINI_VERSION "1.4.5"
diff --git a/vscode/library.lua b/vscode/library.lua
index f581325..2e8883d 100644
--- a/vscode/library.lua
+++ b/vscode/library.lua
@@ -901,3 +901,13 @@ key.RCTRL = 228
 key.RSHIFT = 229
 key.RALT = 230
 key.RGUI = 231
+
+---@class utf8
+utf8 = {}
+
+---@param str string
+---@param startchr number
+---@param endchr number
+---@return string
+---Returns whether the specified keyboard key is down
+function utf8.sub(str, startchr, endchr) end