support event handlers

I've agonized over conflicts between editor and script handlers for a
while, but finally the solution occurred to me: to use the script's
handlers, hide the editor. To use the editor's handlers, show the
editor. The menu and settings are always active. This seems nice and
consistent, easy to explain.

Mike Stein would prefer we just supported love.* handlers in scripts to
minimize special cases and cognitive load for people. But I'd rather
err on the side of being transparent about what's going on inside. As a
compromise I'm supporting love.* names at least in addition to my
rephrasings (which came about mostly because love.keychordpressed is
just too much of a mouthful)

0004-on.update

@@ -1,4 +1,4 @@
-on.update = function()
+on.update = function(dt)
 	refresh_debug_animations()
 	if App.mouse_down(1) then
 		update_any_sliders(App.mouse_x(), App.mouse_y())
@@ -8,4 +8,5 @@ on.update = function()
 	elseif Current_pane.output_editor_state.scrollbar_drag then
 		adjust_scrollbar(Current_pane.output_editor_state, App.mouse_y())
 	end
+	if car.update then car.update(dt) end
 end

0012-on.draw

@@ -2,6 +2,8 @@ on.draw = function()
 	Global_state.button_handlers = {}
 	love.graphics.setBackgroundColor(Background_color.r, Background_color.g, Background_color.b)
 	draw_canvas()
+	App.color(Foreground_color)
+	if car.draw then car.draw() end  -- off canvas
 	if Show_code then
 		draw_editor_border()
 		edit.draw(Current_pane.editor_state, --[[implicitly use Foreground_color]] nil, --[[hide_cursor]] nil, --[[show_line_numbers]] true)

0013-on.keychord_press

@@ -5,8 +5,14 @@ on.keychord_press = function(chord, key)
 		update_font_settings(Current_pane.editor_state.font_height-2)
 	elseif chord == 'C-0' then
 		update_font_settings(20)
-	elseif Current_pane.editor_state.cursor_x then
-		-- send keys to editor if cursor is visible
-		edit.keychord_press(Current_pane.editor_state, chord, key)
+	elseif Show_code then
+		if Current_pane.editor_state.cursor_x then
+			-- send keys to editor if cursor is visible
+			edit.keychord_press(Current_pane.editor_state, chord, key)
+		end
+	else
+		-- editors hidden
+		if car.keychord_press then car.keychord_press(chord, key) end
+		if car.keypressed then car.keypressed(key) end
 	end
 end

0014-on.text_input

@@ -1,5 +1,11 @@
 on.text_input = function(t)
-	if Current_pane.editor_state.cursor_x then
-		edit.text_input(Current_pane.editor_state, t)
+	if Show_code then
+		if Current_pane.editor_state.cursor_x then
+			edit.text_input(Current_pane.editor_state, t)
+		end
+	else
+		-- editors hidden
+		if car.text_input then car.text_input(t) end
+		if car.textinput then car.textinput(t) end
 	end
 end

0015-on.key_release

@@ -1,5 +1,11 @@
 on.key_release = function(key, scancode)
-	if Current_pane.editor_state.cursor_x then
-		edit.key_release(Current_pane.editor_state, key, scancode)
+	if Show_code then
+		if Current_pane.editor_state.cursor_x then
+			edit.key_release(Current_pane.editor_state, key, scancode)
+		end
+	else
+		-- editors hidden
+		if car.key_release then car.key_release(key, scancode) end
+		if car.keyreleased then car.keyreleased(key, scancode) end
 	end
 end

0016-on.mouse_press

@@ -8,16 +8,22 @@ on.mouse_press = function(x,y, mouse_button)
 	if not on_area(Settings_menu_area, x,y) then
 		Show_settings = false
 	end
-	if on_editor_scrollbar(Current_pane.editor_state, x,y) then
-		Current_pane.editor_state.scrollbar_drag = true
-	elseif on_editor_scrollbar_area(Current_pane.editor_state, x,y) then
-		-- nothing
-	elseif x < Current_pane.editor_state.right + 15 - 5 and y < Current_pane.editor_state.bottom + 5 + 10 - 5 then
-		love.keyboard.setTextInput(true)
-		edit.mouse_press(Current_pane.editor_state, x,y, mouse_button)
-	elseif on_editor_scrollbar(Current_pane.output_editor_state, x,y) then
-		Current_pane.output_editor_state.scrollbar_drag = true
-	elseif on_editor_scrollbar_area(Current_pane.output_editor_state, x,y) then
-		-- nothing
+	if Show_code then
+		if on_editor_scrollbar(Current_pane.editor_state, x,y) then
+			Current_pane.editor_state.scrollbar_drag = true
+		elseif on_editor_scrollbar_area(Current_pane.editor_state, x,y) then
+			-- nothing
+		elseif x < Current_pane.editor_state.right + 15 - 5 and y < Current_pane.editor_state.bottom + 5 + 10 - 5 then
+			love.keyboard.setTextInput(true)
+			edit.mouse_press(Current_pane.editor_state, x,y, mouse_button)
+		elseif on_editor_scrollbar(Current_pane.output_editor_state, x,y) then
+			Current_pane.output_editor_state.scrollbar_drag = true
+		elseif on_editor_scrollbar_area(Current_pane.output_editor_state, x,y) then
+			-- nothing
+		end
+	else
+		-- editors hidden
+		if car.mouse_press then car.mouse_press(x,y, mouse_button) end
+		if car.mousepressed then car.mousepressed(x,y, mouse_button) end
 	end
 end

0017-on.mouse_release

@@ -1,16 +1,22 @@
 on.mouse_release = function(x,y, mouse_button)
 	Selected_slider = nil
-	if Current_pane.editor_state.scrollbar_drag then
-		adjust_scrollbar(Current_pane.editor_state, y)
-		Current_pane.editor_state.scrollbar_drag = nil
-	elseif on_editor_scrollbar_area(Current_pane.editor_state, x,y) then
-		adjust_scrollbar(Current_pane.editor_state, y)
-	elseif x < Current_pane.editor_state.right + 15 - 5 and y < Current_pane.editor_state.bottom + 5 + 10 - 5 then
-		edit.mouse_release(Current_pane.editor_state, x,y, mouse_button)
-	elseif Current_pane.output_editor_state.scrollbar_drag then
-		adjust_scrollbar(Current_pane.output_editor_state, y)
-		Current_pane.output_editor_state.scrollbar_drag = nil
-	elseif on_editor_scrollbar_area(Current_pane.output_editor_state, x,y) then
-		adjust_scrollbar(Current_pane.output_editor_state, y)
+	if Show_code then
+		if Current_pane.editor_state.scrollbar_drag then
+			adjust_scrollbar(Current_pane.editor_state, y)
+			Current_pane.editor_state.scrollbar_drag = nil
+		elseif on_editor_scrollbar_area(Current_pane.editor_state, x,y) then
+			adjust_scrollbar(Current_pane.editor_state, y)
+		elseif x < Current_pane.editor_state.right + 15 - 5 and y < Current_pane.editor_state.bottom + 5 + 10 - 5 then
+			edit.mouse_release(Current_pane.editor_state, x,y, mouse_button)
+		elseif Current_pane.output_editor_state.scrollbar_drag then
+			adjust_scrollbar(Current_pane.output_editor_state, y)
+			Current_pane.output_editor_state.scrollbar_drag = nil
+		elseif on_editor_scrollbar_area(Current_pane.output_editor_state, x,y) then
+			adjust_scrollbar(Current_pane.output_editor_state, y)
+		end
+	else
+		-- editors hidden
+		if car.mouse_release then car.mouse_release(x,y, mouse_button) end
+		if car.mousereleased then car.mousereleased(x,y, mouse_button) end
 	end
 end

0100-car

@@ -0,0 +1,2 @@
+-- Table where any handlers for the current pane will live.
+car = {}

0101-on.mouse_wheel_move

@@ -0,0 +1,9 @@
+on.mouse_wheel_move = function(dx,dy)
+	if Show_code then
+		-- nothing yet
+	else
+		-- editors hidden
+		if car.mouse_wheel_move then car.mouse_wheel_move(dx,dy) end
+		if car.wheelmoved then car.wheelmoved(dx,dy) end
+	end
+end