Yield for "frame_pre_draw" signal before writing to terminal

Fixes #41. But creates another issue where sometimes the yield will
resume after the terminal node has already been freed logging an error
to the console.

Also a few changes to where update is called it the gdnative terminal
code.

Also changed gdnative terminal to only accept strings.

addons/godot_xterm/native/src/terminal.cpp

@@ -1,3 +1,5 @@
+// Copyright (c) 2021, Leroy Hopson (MIT License).
+
 #include "terminal.h"
 #include <Dictionary.hpp>
 #include <InputEventKey.hpp>
@@ -543,36 +545,14 @@ void Terminal::update_size() {
   rows = std::max(2, (int)floor(get_rect().size.y / cell_size.y));
   cols = std::max(1, (int)floor(get_rect().size.x / cell_size.x));
 
-  emit_signal("size_changed", Vector2(cols, rows));
-
   tsm_screen_resize(screen, cols, rows);
 
-  update();
+  emit_signal("size_changed", Vector2(cols, rows));
 }
 
-void Terminal::write(Variant data) {
-  const char *u8;
-  size_t len;
-
-  switch (data.get_type()) {
-  case Variant::Type::POOL_BYTE_ARRAY: {
-    PoolByteArray bytes = data;
-    u8 = (char *)bytes.read().ptr();
-    len = bytes.size();
-    break;
-  }
-  case Variant::Type::STRING: {
-    String string = data;
-    u8 = string.alloc_c_string();
-    len = strlen(u8);
-    break;
-  }
-  default:
-    WARN_PRINT("Method expected a String or PoolByteArray");
-    return;
-  }
+void Terminal::write(String data) {
+  const char *u8 = data.alloc_c_string();
+  size_t len = strlen(u8);
 
   tsm_vte_input(vte, u8, len);
-
-  update();
 }

addons/godot_xterm/native/src/terminal.h

@@ -1,3 +1,5 @@
+// Copyright (c) 2021, Leroy Hopson (MIT License).
+
 #ifndef TERMINAL_H
 #define TERMINAL_H
 
@@ -52,7 +54,7 @@ public:
   void _gui_input(Variant event);
   void _draw();
 
-  void write(Variant data);
+  void write(String data);
 
   enum UpdateMode {
     DISABLED,

addons/godot_xterm/nodes/terminal/terminal.gd

@@ -16,13 +16,18 @@ enum UpdateMode {
 
 export (UpdateMode) var update_mode = UpdateMode.AUTO setget set_update_mode
 
-var rows: int setget , get_rows  # TODO: Show in inspector.
-var cols: int setget , get_cols  # TODO: Show in inspector.
+var cols = 2
+var rows = 2
 
 var _viewport: Viewport = preload("./viewport.tscn").instance()
 var _native_terminal: Control = _viewport.get_node("Terminal")
 var _screen := TextureRect.new()
 var _visibility_notifier := VisibilityNotifier2D.new()
+var _dirty := false
+
+var buffer := StreamPeerBuffer.new()
+
+var times = 0
 
 
 func set_update_mode(value):
@@ -31,16 +36,22 @@ func set_update_mode(value):
 
 
 func get_rows() -> int:
-	return _native_terminal.rows
+	return 0
 
 
 func get_cols() -> int:
-	return _native_terminal.cols
+	return 0
 
 
 func write(data) -> void:
 	assert(data is String or data is PoolByteArray)
-	_native_terminal.write(data)
+
+	# FIXME: This will occasionally cause a "Resumed function after yield, but class instance is gone" error after freeing the Terminal instance.
+	# However, this yield is necessary to ensure the terminal state machines framebuffer is up to date when we make all the draw_* calls.
+	yield(VisualServer, "frame_pre_draw")
+
+	_native_terminal.write(data if data is String else data.get_string_from_utf8())
+	_native_terminal.update()
 
 
 func _ready():
@@ -96,4 +107,13 @@ func _on_key_pressed(data: String, event: InputEventKey):
 
 
 func _on_size_changed(new_size: Vector2):
+	cols = new_size.x
+	rows = new_size.y
 	emit_signal("size_changed", new_size)
+
+
+func _set_size_warning(value):
+	if value:
+		push_warning(
+			"Terminal cols and rows are read only and determined by the font and rect sizes."
+		)