From deff67c224de54d700749c6ea50004fb3311558a Mon Sep 17 00:00:00 2001
From: Uks2 <tom@tomg.xyz>
Date: Mon, 20 Jun 2022 17:23:11 +0100
Subject: [PATCH] Add title_change event for views

Works in basically the same way as all the other events (I hope!),
allows the config script to update a status bar or whatever.
---
 include/desktop/view.h    |  2 ++
 kiwmi/desktop/view.c      |  1 +
 kiwmi/desktop/xdg_shell.c | 10 +++++++
 kiwmi/luak/kiwmi_view.c   | 57 +++++++++++++++++++++++++++++++++++++++
 lua_docs.md               |  5 ++++
 5 files changed, 75 insertions(+)

diff --git a/include/desktop/view.h b/include/desktop/view.h
index 5ada1bb..be64ca6 100644
--- a/include/desktop/view.h
+++ b/include/desktop/view.h
@@ -51,6 +51,7 @@ struct kiwmi_view {
     struct wl_listener destroy;
     struct wl_listener request_move;
     struct wl_listener request_resize;
+    struct wl_listener set_title;
 
     bool mapped;
 
@@ -60,6 +61,7 @@ struct kiwmi_view {
         struct wl_signal request_resize;
         struct wl_signal post_render;
         struct wl_signal pre_render;
+        struct wl_signal set_title;
     } events;
 
     struct kiwmi_xdg_decoration *decoration;
diff --git a/kiwmi/desktop/view.c b/kiwmi/desktop/view.c
index efd0d66..bf7c381 100644
--- a/kiwmi/desktop/view.c
+++ b/kiwmi/desktop/view.c
@@ -247,6 +247,7 @@ view_create(
     wl_signal_init(&view->events.request_resize);
     wl_signal_init(&view->events.post_render);
     wl_signal_init(&view->events.pre_render);
+    wl_signal_init(&view->events.set_title);
 
     view->desktop_surface.tree = wlr_scene_tree_create(
         &view->desktop->strata[KIWMI_STRATUM_NORMAL]->node);
diff --git a/kiwmi/desktop/xdg_shell.c b/kiwmi/desktop/xdg_shell.c
index 733de40..50ba3f8 100644
--- a/kiwmi/desktop/xdg_shell.c
+++ b/kiwmi/desktop/xdg_shell.c
@@ -127,6 +127,13 @@ xdg_toplevel_request_resize_notify(struct wl_listener *listener, void *data)
     wl_signal_emit(&view->events.request_resize, &new_event);
 }
 
+static void
+xdg_toplevel_set_title_notify(struct wl_listener *listener, void *UNUSED(data))
+{
+    struct kiwmi_view *view = wl_container_of(listener, view, set_title);
+    wl_signal_emit(&view->events.set_title, view);
+}
+
 static void
 xdg_shell_view_close(struct kiwmi_view *view)
 {
@@ -258,6 +265,9 @@ xdg_shell_new_surface_notify(struct wl_listener *listener, void *data)
 
     wlr_xdg_surface_get_geometry(view->xdg_surface, &view->geom);
 
+    view->set_title.notify = xdg_toplevel_set_title_notify;
+    wl_signal_add(&xdg_surface->toplevel->events.set_title, &view->set_title);
+
     wl_list_insert(&desktop->views, &view->link);
 }
 
diff --git a/kiwmi/luak/kiwmi_view.c b/kiwmi/luak/kiwmi_view.c
index 84f9f4c..0a394ee 100644
--- a/kiwmi/luak/kiwmi_view.c
+++ b/kiwmi/luak/kiwmi_view.c
@@ -561,6 +561,32 @@ kiwmi_view_on_request_resize_notify(struct wl_listener *listener, void *data)
     }
 }
 
+static void
+kiwmi_view_on_set_title_notify(struct wl_listener *listener, void *data)
+{
+    struct kiwmi_lua_callback *lc = wl_container_of(listener, lc, listener);
+    struct kiwmi_server *server   = lc->server;
+    lua_State *L                  = server->lua->L;
+    struct kiwmi_view *view       = data;
+
+    lua_rawgeti(L, LUA_REGISTRYINDEX, lc->callback_ref);
+
+    lua_pushcfunction(L, luaK_kiwmi_view_new);
+    lua_pushlightuserdata(L, server->lua);
+    lua_pushlightuserdata(L, view);
+
+    if (lua_pcall(L, 2, 1, 0)) {
+        wlr_log(WLR_ERROR, "%s", lua_tostring(L, -1));
+        lua_pop(L, 1);
+        return;
+    }
+
+    if (lua_pcall(L, 1, 0, 0)) {
+        wlr_log(WLR_ERROR, "%s", lua_tostring(L, -1));
+        lua_pop(L, 1);
+    }
+}
+
 static int
 l_kiwmi_view_on_destroy(lua_State *L)
 {
@@ -665,12 +691,43 @@ l_kiwmi_view_on_request_resize(lua_State *L)
     return 0;
 }
 
+static int
+l_kiwmi_view_on_set_title(lua_State *L)
+{
+    struct kiwmi_object *obj =
+        *(struct kiwmi_object **)luaL_checkudata(L, 1, "kiwmi_view");
+    luaL_checktype(L, 2, LUA_TFUNCTION);
+
+    if (!obj->valid) {
+        return luaL_error(L, "kiwmi_view no longer valid");
+    }
+
+    struct kiwmi_view *view       = obj->object;
+    struct kiwmi_desktop *desktop = view->desktop;
+    struct kiwmi_server *server   = wl_container_of(desktop, server, desktop);
+
+    lua_pushcfunction(L, luaK_kiwmi_lua_callback_new);
+    lua_pushlightuserdata(L, server);
+    lua_pushvalue(L, 2);
+    lua_pushlightuserdata(L, kiwmi_view_on_set_title_notify);
+    lua_pushlightuserdata(L, &view->events.set_title);
+    lua_pushlightuserdata(L, obj);
+
+    if (lua_pcall(L, 5, 0, 0)) {
+        wlr_log(WLR_ERROR, "%s", lua_tostring(L, -1));
+        return 0;
+    }
+
+    return 0;
+}
+
 static const luaL_Reg kiwmi_view_events[] = {
     {"destroy", l_kiwmi_view_on_destroy},
     {"post_render", l_kiwmi_view_on_post_render},
     {"pre_render", l_kiwmi_view_on_pre_render},
     {"request_move", l_kiwmi_view_on_request_move},
     {"request_resize", l_kiwmi_view_on_request_resize},
+    {"set_title", l_kiwmi_view_on_set_title},
     {NULL, NULL},
 };
 
diff --git a/lua_docs.md b/lua_docs.md
index 7f63b60..c4244d6 100644
--- a/lua_docs.md
+++ b/lua_docs.md
@@ -373,3 +373,8 @@ Callback receives the view.
 
 The view wants to start an interactive resize.
 Callback receives a table containing the `view`, and `edges`, containing the edges.
+
+#### set_title
+
+The view's title has changed.
+Callback receives the view.