refactor: extract block state helper

rust/spikes/leptos-tiptap-spike/src/editor_runtime/block_dnd.rs

@@ -3,7 +3,12 @@
 //! 本模块只承接拖拽命中所需的窄 helper，不处理 Leptos signal，
 //! 也不分发 editor command；调用方负责保留编辑器状态编排。
 
-use crate::editor_runtime::block_hover_state::{DropIndicatorState, DropPlacement};
+use crate::{
+    editor_runtime::block_hover_state::{
+        block_label_for_element, DropIndicatorState, DropPlacement, HoveredBlockState,
+    },
+    editor_root_element, editor_stage_element,
+};
 use web_sys::{window, Element, EventTarget};
 
 pub(crate) struct HandleCorridorGeometry {
@@ -124,6 +129,78 @@ pub(crate) fn drop_indicator_from_block_rects(
     )
 }
 
+pub(crate) fn block_state_from_index(index: usize) -> Option<HoveredBlockState> {
+    let root = editor_root_element()?;
+    let stage = editor_stage_element()?;
+    let block = root.children().item(index as u32)?;
+    let block_rect = block.get_bounding_client_rect();
+    let stage_rect = stage.get_bounding_client_rect();
+    let block_height = if block_rect.height() > 0.0 {
+        block_rect.height()
+    } else {
+        28.0
+    };
+
+    Some(HoveredBlockState {
+        index,
+        label: block_label_for_element(&block),
+        top: block_rect.top() - stage_rect.top(),
+        height: block_height,
+    })
+}
+
+pub(crate) fn pointer_in_handle_corridor(
+    client_x: i32,
+    client_y: i32,
+    block: &HoveredBlockState,
+    handle_selector: &str,
+    handle_left_fallback: f64,
+    handle_width: f64,
+) -> bool {
+    let Some(stage) = editor_stage_element() else {
+        return false;
+    };
+    let Some(root) = editor_root_element() else {
+        return false;
+    };
+    let Some(block_element) = root.children().item(block.index as u32) else {
+        return false;
+    };
+
+    let stage_rect = stage.get_bounding_client_rect();
+    let block_rect = block_element.get_bounding_client_rect();
+    let handle_rect = window()
+        .and_then(|win| win.document())
+        .and_then(|document| document.query_selector(handle_selector).ok().flatten())
+        .map(|handle| handle.get_bounding_client_rect());
+
+    let block_left = block_rect.left() - stage_rect.left();
+    let block_top = block_rect.top() - stage_rect.top();
+    let block_bottom = block_rect.bottom() - stage_rect.top();
+    let handle_left = handle_rect
+        .as_ref()
+        .map(|rect| rect.left() - stage_rect.left())
+        .unwrap_or(handle_left_fallback);
+    let handle_right = handle_rect
+        .as_ref()
+        .map(|rect| rect.right() - stage_rect.left())
+        .unwrap_or_else(|| handle_left + handle_width);
+
+    pointer_in_handle_corridor_geometry(
+        client_x,
+        client_y,
+        &HandleCorridorGeometry {
+            stage_left: stage_rect.left(),
+            stage_top: stage_rect.top(),
+            block_left,
+            block_top,
+            block_bottom,
+            handle_left,
+            handle_right,
+        },
+    )
+}
+
 pub(crate) fn top_level_block_index(root: &Element, block: &Element) -> Option<usize> {
     let children = root.children();
     (0..children.length()).find_map(|index| {