/**
 * 应用编译期的ReactFlow可见性扩展。为视口外但仍有焦点/手势/浮层的显式保留对象扩展原生可见集合。
 * 只转换匹配到的编译输入字符串，不修改共享node_modules文件，也不进入独立headless SDK的运行逻辑。
 */
// App-only extension for the pinned @xyflow/react 12.12.1 ESM renderer. This
// transforms compiler input; shared node_modules and the headless SDK are untouched.
// 读取安装包版本，固定12.12.1；库升级必须人工审查目标实现，不能凭相同函数名继续替换。
const version = require('@xyflow/react/package.json').version;
/** webpack/Turbopack loader接收源码并返回改写后的源码；任何版本或锚点不符立即失败，防止悄悄失去保留能力。 */
module.exports = function retainVisibility(source) {
  if (version !== '12.12.1') throw new Error('Review xyflow retained visibility before upgrading @xyflow/react');
  // 四个精确源码锚点覆盖节点查询、边可见性及选择订阅；依赖上游编译格式，不是通用AST补丁。
  const nodes = 'getNodesInside(s.nodeLookup, { x: 0, y: 0, width: s.width, height: s.height }, s.transform, true).map((node) => node.id)';
  const edges = 'isEdgeVisible({\n                        sourceNode,';
  const selection = 'const changeSelector = (s) => !!s.onSelectionChangeHandlers;';
  const close = 'transform: s.transform,\n                    })) {';
  // 每个锚点只能出现一次，并拒绝重复处理已含标记的输入；避免替换错位置或把运算括号重复扩展。
  if (source.includes('__endoleapRetain') || source.split(nodes).length !== 2 || source.split(edges).length !== 2 || source.split(close).length !== 2 || source.split(selection).length !== 2) {
    throw new Error('Unsupported xyflow visibility implementation; retained editors must not silently lose virtualization');
  }
  // 节点追加未hidden且显式保留的ID并Set去重；边以保留标记或原可见判断二选一，维持原生索引。
  // 最后一处改为空数组不订阅完整选择集合，减少无选择监听时的不必要全图selector工作。
  return source
    .replace(nodes, `Array.from(new Set([
      ...${nodes},
      ...s.nodes.filter((node) => node.__endoleapRetain === true && !node.hidden).map((node) => node.id),
    ]))`)
    .replace(edges, '(edge.__endoleapRetain === true || isEdgeVisible({\n                        sourceNode,')
    .replace(close, 'transform: s.transform,\n                    }))) {')
    // An empty handler array is truthy; do not mount the full-graph selector
    // when neither the prop nor a useOnSelectionChange subscriber needs it.
    .replace(selection, 'const changeSelector = (s) => !!s.onSelectionChangeHandlers?.length;');
};