3 files changed, 61 insertions, 51 deletions

diff --git a/src/nvim/msgpack_rpc/remote_ui.c b/src/nvim/msgpack_rpc/remote_ui.c
index e27d4383c0..a0bc573698 100644
--- a/src/nvim/msgpack_rpc/remote_ui.c
+++ b/src/nvim/msgpack_rpc/remote_ui.c
@@ -27,12 +27,15 @@ void remote_ui_init(void)
 {
   connected_uis = pmap_new(uint64_t)();
   // Add handler for "attach_ui"
-  String method = cstr_as_string("attach_ui");
+  String method = cstr_as_string("ui_attach");
   MsgpackRpcRequestHandler handler = {.fn = remote_ui_attach, .defer = false};
   msgpack_rpc_add_method_handler(method, handler);
-  method = cstr_as_string("detach_ui");
+  method = cstr_as_string("ui_detach");
   handler.fn = remote_ui_detach;
   msgpack_rpc_add_method_handler(method, handler);
+  method = cstr_as_string("ui_try_resize");
+  handler.fn = remote_ui_try_resize;
+  msgpack_rpc_add_method_handler(method, handler);
 }
 
 void remote_ui_disconnect(uint64_t channel_id)
@@ -95,7 +98,6 @@ static Object remote_ui_attach(uint64_t channel_id, uint64_t request_id,
   ui->suspend = remote_ui_suspend;
   pmap_put(uint64_t)(connected_uis, channel_id, ui);
   ui_attach(ui);
-
   return NIL;
 }
 
@@ -110,6 +112,30 @@ static Object remote_ui_detach(uint64_t channel_id, uint64_t request_id,
   return NIL;
 }
 
+static Object remote_ui_try_resize(uint64_t channel_id, uint64_t request_id,
+                                   Array args, Error *error)
+{
+  if (!pmap_has(uint64_t)(connected_uis, channel_id)) {
+    api_set_error(error, Exception, _("UI is not attached for channel"));
+  }
+
+  if (args.size != 2 || args.items[0].type != kObjectTypeInteger
+      || args.items[1].type != kObjectTypeInteger
+      || args.items[0].data.integer <= 0 || args.items[1].data.integer <= 0) {
+    api_set_error(error, Validation,
+                  _("Arguments must be a pair of positive integers "
+                    "representing the remote screen width/height"));
+    return NIL;
+  }
+
+  UI *ui = pmap_get(uint64_t)(connected_uis, channel_id);
+  ui->width = (int)args.items[0].data.integer;
+  ui->height = (int)args.items[1].data.integer;
+  ui_refresh();
+  return NIL;
+}
+
+
 static void push_call(UI *ui, char *name, Array args)
 {
   Array call = ARRAY_DICT_INIT;
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index 68589522c4..c2fb34cde0 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -6529,7 +6529,6 @@ do_highlight (
 
         if (is_normal_group) {
           normal_fg = HL_TABLE()[idx].sg_rgb_fg;
-          ui_fg_updated();
         }
       } else if (STRCMP(key, "GUIBG") == 0)   {
         if (!init || !(HL_TABLE()[idx].sg_set & SG_GUI)) {
@@ -6548,7 +6547,6 @@ do_highlight (
 
         if (is_normal_group) {
           normal_bg = HL_TABLE()[idx].sg_rgb_bg;
-          ui_bg_updated();
         }
       } else if (STRCMP(key, "GUISP") == 0)   {
         // Ignored
@@ -6645,6 +6643,10 @@ do_highlight (
     if (is_normal_group) {
       HL_TABLE()[idx].sg_term_attr = 0;
       HL_TABLE()[idx].sg_cterm_attr = 0;
+      if (abstract_ui) {
+        // If the normal group has changed, it is simpler to refresh every UI
+        ui_refresh();
+      }
     } else
       set_hl_attr(idx);
     HL_TABLE()[idx].sg_scriptID = current_SID;
diff --git a/src/nvim/ui.c b/src/nvim/ui.c
index cd8c3b73e6..de92079ada 100644
--- a/src/nvim/ui.c
+++ b/src/nvim/ui.c
@@ -64,7 +64,7 @@ static HlAttrs current_attrs = {
   false, false, false, false, false, false, -1, -1
 };
 static bool cursor_enabled = true;
-static int height = INT_MAX, width = INT_MAX;
+static int height, width;
 
 // This set of macros allow us to use UI_CALL to invoke any function on
 // registered UI instances. The functions can have 0-5 arguments(configurable
@@ -113,18 +113,6 @@ void ui_write(uint8_t *s, int len)
     free(tofree);
 }
 
-void ui_fg_updated(void)
-{
-  UI_CALL(update_fg, normal_fg);
-  UI_CALL(flush);
-}
-
-void ui_bg_updated(void)
-{
-  UI_CALL(update_bg, normal_bg);
-  UI_CALL(flush);
-}
-
 /*
  * If the machine has job control, use it to suspend the program,
  * otherwise fake it by starting a new shell.
@@ -177,10 +165,32 @@ void ui_cursor_shape(void)
   }
 }
 
-void ui_resize(int width, int height)
+void ui_refresh(void)
 {
-  ui_fg_updated();
-  ui_bg_updated();
+  width = height = INT_MAX;
+
+  for (size_t i = 0; i < ui_count; i++) {
+    UI *ui = uis[i];
+    width = ui->width < width ? ui->width : width;
+    height = ui->height < height ? ui->height : height;
+  }
+
+  screen_resize(width, height, true);
+}
+
+void ui_resize(int new_width, int new_height)
+{
+  width = new_width;
+  height = new_height;
+
+  if (normal_fg != -1) {
+    UI_CALL(update_fg, normal_fg);
+  }
+
+  if (normal_bg != -1) {
+    UI_CALL(update_bg, normal_bg);
+  }
+
   sr.top = 0;
   sr.bot = height - 1;
   sr.left = 0;
@@ -254,7 +264,7 @@ void ui_attach(UI *ui)
   }
 
   uis[ui_count++] = ui;
-  resized(ui);
+  ui_refresh();
 }
 
 void ui_detach(UI *ui)
@@ -281,17 +291,8 @@ void ui_detach(UI *ui)
 
   ui_count--;
 
-  if (ui->width == width || ui->height == height) {
-    // It is possible that the UI being detached had the smallest screen,
-    // so check for the new minimum dimensions
-    width = height = INT_MAX;
-    for (size_t i = 0; i < ui_count; i++) {
-      check_dimensions(uis[i]);
-    }
-  }
-
   if (ui_count) {
-    screen_resize(width, height, true);
+    ui_refresh();
   }
 }
 
@@ -474,25 +475,6 @@ static void parse_abstract_ui_codes(uint8_t *ptr, int len)
   UI_CALL(flush);
 }
 
-static void resized(UI *ui)
-{
-  check_dimensions(ui);
-  screen_resize(width, height, true);
-}
-
-static void check_dimensions(UI *ui)
-{
-  // The internal screen dimensions are always the minimum required to fit on
-  // all connected screens
-  if (ui->width < width) {
-    width = ui->width;
-  }
-
-  if (ui->height < height) {
-    height = ui->height;
-  }
-}
-
 static void ui_linefeed(void)
 {
   int new_col = 0;