feat: add html.element lua helper

4 files changed, 50 insertions, 8 deletions

diff --git a/examples/site/build.lua b/examples/site/build.lua
index 0b9e67a..4d0939a 100644
--- a/examples/site/build.lua
+++ b/examples/site/build.lua
@@ -1,9 +1,5 @@
 -- External scripts are resolved relative to the HTML file that includes them :)
 
-local function element(tag, attributes, children)
-  return { tag = tag, attributes = attributes or {}, children = children or {} }
-end
-
 local function find_by_class(node, wanted)
   if type(node) ~= "table" then return nil end
   local classes = node.attributes and node.attributes.class or ""
@@ -27,7 +23,7 @@ local features = {
 
 local feature_list = assert(find_by_class(page, "feature-list"))
 for _, feature in ipairs(features) do
-  table.insert(feature_list.children, element("li", {}, { feature }))
+  table.insert(feature_list.children, html.element("li", nil, { feature }))
 end
 
 local entries = {}
@@ -41,8 +37,8 @@ summary.text = tostring(#entries) .. " entries"
 
 local file_list = assert(find_by_class(page, "file-list"))
 for _, entry in ipairs(entries) do
-  table.insert(file_list.children, element("li", {}, {
-    element("code", {}, { entry.path }),
+  table.insert(file_list.children, html.element("li", nil, {
+    html.element("code", nil, { entry.path }),
     " (", entry.type, ")"
   }))
 end
@@ -54,7 +50,7 @@ local mixed = assert(find_by_class(page, "mixed-content"))
 mixed.children = {
   { kind = "comment", text = "generated by Lua" },
   "Text with ",
-  element("strong", {}, { "an element" }),
+  html.element("strong", nil, { "an element" }),
   "."
 }
 
diff --git a/src/Dom/Dom.c b/src/Dom/Dom.c
index ede7ddd..6dc6760 100644
--- a/src/Dom/Dom.c
+++ b/src/Dom/Dom.c
@@ -6,6 +6,50 @@
 #include <string.h>
 #include <strings.h>
 
+static int html_element(lua_State *lua) {
+  const char *tag;
+
+  luaL_checktype(lua, 1, LUA_TSTRING);
+  tag = lua_tostring(lua, 1);
+  if (tag[0] == '\0') {
+    return luaL_argerror(lua, 1, "tag cannot be empty");
+  }
+  if (!lua_isnoneornil(lua, 2)) {
+    luaL_checktype(lua, 2, LUA_TTABLE);
+  }
+  if (!lua_isnoneornil(lua, 3)) {
+    luaL_checktype(lua, 3, LUA_TTABLE);
+  }
+
+  lua_newtable(lua);
+
+  lua_pushvalue(lua, 1);
+  lua_setfield(lua, -2, "tag");
+
+  if (lua_istable(lua, 2)) {
+    lua_pushvalue(lua, 2);
+  } else {
+    lua_newtable(lua);
+  }
+  lua_setfield(lua, -2, "attributes");
+
+  if (lua_istable(lua, 3)) {
+    lua_pushvalue(lua, 3);
+  } else {
+    lua_newtable(lua);
+  }
+  lua_setfield(lua, -2, "children");
+
+  return 1;
+}
+
+void dom_register_html(lua_State *lua) {
+  lua_newtable(lua);
+  lua_pushcfunction(lua, html_element);
+  lua_setfield(lua, -2, "element");
+  lua_setglobal(lua, "html");
+}
+
 static int absolute_index(lua_State *lua, int index) {
   return index < 0 ? lua_gettop(lua) + index + 1 : index;
 }
diff --git a/src/Dom/Dom.h b/src/Dom/Dom.h
index 06bd1ff..bee6cd1 100644
--- a/src/Dom/Dom.h
+++ b/src/Dom/Dom.h
@@ -6,5 +6,6 @@
 
 void dom_push_page(lua_State *lua, const xmlNode *root);
 xmlNodePtr dom_page_from_lua(lua_State *lua, int table_index);
+void dom_register_html(lua_State *lua);
 
 #endif
diff --git a/src/LuaEngine/LuaEngine.c b/src/LuaEngine/LuaEngine.c
index 319f408..c34fd68 100644
--- a/src/LuaEngine/LuaEngine.c
+++ b/src/LuaEngine/LuaEngine.c
@@ -257,6 +257,7 @@ int process_html_document(htmlDocPtr document, const char *input_path) {
 
   luaL_openlibs(lua);
   register_yapssg(lua);
+  dom_register_html(lua);
   lua_logger_register(lua);
   directory_walker_register(lua, input_path);
   dom_push_page(lua, root);