Improve input handling and scrolling logic in multiline text views

- Refined padding calculations in `view_text.v` to ensure correct scroll container height.

Author: mike-ward

examples/multiline_input.v

@@ -3,6 +3,9 @@ import gui
 // Multiline Input Demo
 // =============================
 
+const input_id_focus = 1
+const input_id_scroll = 1
+
 @[heap]
 struct MultilineApp {
 mut:
@@ -18,6 +21,7 @@ fn main() {
 		cursor_blink: true
 		on_init:      fn (mut w gui.Window) {
 			w.update_view(main_view)
+			w.set_id_focus(input_id_focus)
 		}
 	)
 	window.set_theme(gui.theme_dark_bordered)
@@ -34,8 +38,8 @@ fn main_view(window &gui.Window) gui.View {
 		sizing:  gui.fixed_fixed
 		content: [
 			gui.input(
-				id_focus:        1
-				id_scroll:       1
+				id_focus:        input_id_focus
+				id_scroll:       input_id_scroll
 				scroll_mode:     .vertical_only
 				text:            app.text
 				mode:            .multiline

view_input.v

@@ -164,24 +164,25 @@ pub fn input(cfg InputCfg) View {
 		max_width:       cfg.max_width
 		min_height:      cfg.min_height
 		max_height:      cfg.max_height
-		padding:         cfg.padding_border
+		disabled:        cfg.disabled
 		color:           cfg.color_border
+		invisible:       cfg.invisible
 		fill:            cfg.fill_border
-		sizing:          cfg.sizing
+		padding:         cfg.padding_border
 		radius:          cfg.radius_border
-		disabled:        cfg.disabled
-		invisible:       cfg.invisible
+		sizing:          cfg.sizing
 		on_char:         cfg.on_char
-		amend_layout:    cfg.amend_layout
 		on_hover:        cfg.hover
+		amend_layout:    cfg.amend_layout
 		content:         [
 			row(
 				name:     'input interior'
 				color:    cfg.color
-				padding:  cfg.padding
+				clip:     true
 				fill:     cfg.fill
-				sizing:   fill_fill
+				padding:  cfg.padding
 				radius:   cfg.radius
+				sizing:   fill_fill
 				spacing:  spacing_small
 				on_click: cfg.on_click_interior
 				content:  [

view_text.v

@@ -228,11 +228,18 @@ fn (tv &TextView) mouse_up_locked(layout &Layout, mut e Event, mut w Window) {
 // adjusts the scroll offset if the cursor is outside the current visible
 // area.
 fn scroll_cursor_into_view(cursor_pos int, layout &Layout, _ &Event, mut w Window) {
+	id_scroll_container := layout.shape.id_scroll_container
+
 	// Find the scroll container and calculate height. (need to start at the root layout)
-	scroll_container := w.layout.find_layout(fn [layout] (ly Layout) bool {
-		return ly.shape.id_scroll == layout.shape.id_scroll_container
+	scroll_container := w.layout.find_layout(fn [id_scroll_container] (ly Layout) bool {
+		return ly.shape.id_scroll == id_scroll_container
 	}) or { return }
-	scroll_view_height := scroll_container.shape.height - scroll_container.shape.padding.height()
+
+	mut padding_height := scroll_container.shape.padding.height()
+	if scroll_container.children.len > 0 {
+		padding_height += scroll_container.children[0].shape.padding.height()
+	}
+	scroll_view_height := scroll_container.shape.height - padding_height
 
 	// Find the index of the line where the cursor is located.
 	mut line_idx := 0
@@ -252,18 +259,18 @@ fn scroll_cursor_into_view(cursor_pos int, layout &Layout, _ &Event, mut w Windo
 	cursor_h_y := cursor_y + scroll_view_height - lh
 
 	// Calculate scroll offsets for current visible region
-	current_scroll_y := w.view_state.scroll_y[layout.shape.id_scroll_container]
-	current_scroll_h_y := current_scroll_y - scroll_view_height
+	current_scroll_y := w.view_state.scroll_y[id_scroll_container]
+	current_scroll_h_y := current_scroll_y - scroll_view_height + lh
 
 	// Determine if we need to scroll:
 	// 1. If cursor is above the current view
 	// 2. If cursor is below the current view
 	new_scroll_y := match true {
-		cursor_y > current_scroll_y { cursor_y }
-		cursor_y <= current_scroll_h_y { cursor_h_y }
+		cursor_y > current_scroll_y { cursor_y - 1 }
+		cursor_y < current_scroll_h_y { cursor_h_y }
 		else { current_scroll_y }
 	}
-	w.scroll_vertical_to(layout.shape.id_scroll_container, new_scroll_y)
+	w.scroll_vertical_to(id_scroll_container, new_scroll_y)
 }
 
 // mouse_cursor_pos determines the character index (cursor position) within