/**
 * 分区节点：展示名称、边框、成员拖入/移出反馈，以及子画布折叠与概览设置。
 * 局部状态只存名称输入草稿；保存与分区属性修改都交给作用域编辑接口，成员归属不由本组件直接变更。
 */
"use client";

import { useContext, useEffect, useRef, useState } from "react";
import { FoldVertical, UnfoldVertical, ExternalLink } from "lucide-react";
import { Handle, NodeToolbar, Position, useViewport, type NodeProps } from "@xyflow/react";
import { AnimatePresence, motion, useReducedMotion } from "motion/react";
import type { CanvasNode } from "@/lib/canvas";
import { TransformableNode, ResizeToggle } from "./transformable-node";
import { FrameFeedback } from "./frame-feedback";
import { FrameLabelMenu } from "./frame-label-menu";
import { ContentHandles } from "./content-handles";
import {useCanvasOverlay} from "./canvas-overlays";
import {useScopedNodeEditing} from "./node-editing";
import styles from "./canvas.module.css";

/** directAnchors用于新版分区四向连接点；子画布ports则按输入/输出方向单独布局。
 * 分区使用自己的设置浮层，因此隐藏TransformableNode的通用样式栏，仍保留公共变换行为。 */
export function FrameNode(props: NodeProps<CanvasNode> & { directAnchors?: boolean }) {
  const { directAnchors = false, ...nodeProps } = props;
  const { id, data, selected } = nodeProps;
  // 设置浮层注册到当前视图的overlay索引，让Portal中的控件也能正确参与焦点与输入路由。
  const overlay=useCanvasOverlay(id,"frame-settings");
  const editing = useScopedNodeEditing(id,data.__headlessTarget);
  const feedback = useContext(FrameFeedback);
  // 反馈来自当前拖动预计算，只统计跨分区的进入/离开；这两个计数不是持久成员列表。
  const incoming = feedback.drops.filter((drop) => drop.to === id && drop.from !== id).length;
  const outgoing = feedback.drops.filter((drop) => drop.from === id && drop.to !== id).length;
  const { zoom } = useViewport();
  const reduce = useReducedMotion();
  // 名称是受控输入草稿；外部data.title变化时同步覆盖，实际提交发生在blur。
  const [title, setTitle] = useState(data.title);
  useEffect(() => setTitle(data.title), [data.title]);
  // Escape恢复模型标题并标记跳过随后的blur保存；Enter排除输入法组合态后通过blur统一提交。
  const cancelBlur = useRef(false);
  const mode = data.labelMode || "fixed";
  /** 去除首尾空白，空名称回退“未命名分区”；只有与模型不同才派发修改，再归一化输入显示。 */
  function saveTitle() {
    const name = title.trim() || "未命名分区";
    if (name !== data.title) editing.frame(id, { title: name });
    setTitle(name);
  }
  // 选中时显示设置栏，动画尊重减少动态效果偏好；栏内事件停止冒泡，避免触发画布快捷键或拖动。
  // 折叠切换前按viewScale还原当前尺寸，存入原状态对应的expandedSize/collapsedSize供后续恢复。
  // 概览比例输入限定5%—400%，只更新presentation.contentScale；链接单独打开子画布。
  // fixed名称与拖放提示用1/(zoom*viewScale)抵消缩放，scaled跟随画布，hidden不绘制名称。
  // 四侧边框提供拖动命中区域；ports按同方向均匀分布，输出在右侧可起连线，输入在左侧可收连线。
  return <>
    <AnimatePresence>{selected && <NodeToolbar style={{ zIndex: 100, pointerEvents: "auto" }} isVisible={true} position={Position.Top} offset={45}>
      <motion.div ref={overlay} className={`${styles.styleToolbar} nodrag nopan nowheel`} role="toolbar" aria-label="分区设置"
        initial={{ opacity: 0, y: reduce ? 0 : 5 }} animate={{ opacity: 1, y: 0 }} exit={{ opacity: 0, y: reduce ? 0 : 5 }} transition={{ duration: reduce ? 0 : 0.14 }}
        onPointerDown={(event) => event.stopPropagation()} onClick={(event) => event.stopPropagation()} onDoubleClick={(event) => event.stopPropagation()} onKeyDown={(event) => event.stopPropagation()}>
        <input className={styles.frameNameInput} aria-label="分区名称" value={title} maxLength={300} onChange={(event) => setTitle(event.target.value)} onBlur={() => { if (cancelBlur.current) cancelBlur.current = false; else saveTitle(); }}
          onKeyDown={(event) => { if (event.key === "Enter" && !event.nativeEvent.isComposing) { event.currentTarget.blur(); } if (event.key === "Escape") { cancelBlur.current = true; setTitle(data.title); event.currentTarget.blur(); } }} />
        <FrameLabelMenu value={mode} change={(labelMode) => editing.frame(id, { labelMode })} />
        <ResizeToggle id={id} renderedTarget={data.__headlessTarget} />
        {data.subgraph && <><button type="button" aria-label={data.presentation?.collapsed ? "展开子画布" : "收起子画布"} title={data.presentation?.collapsed ? "展开子画布" : "收起子画布"} onClick={() => {
          const collapsed = !data.presentation?.collapsed;
          const currentSize = { width: (props.width || 640) / (data.viewScale || 1), height: (props.height || 400) / (data.viewScale || 1) };
          const presentation = { ...data.presentation, collapsed, [collapsed ? "expandedSize" : "collapsedSize"]: currentSize };
          editing.frame(id, { presentation });
        }}>{data.presentation?.collapsed ? <UnfoldVertical size={16} /> : <FoldVertical size={16} />}</button>
        <label className={styles.subgraphScale} title="子画布概览比例，不修改内容尺寸"><input aria-label="子画布概览比例" type="number" min={5} max={400} step={5} value={Math.round((data.presentation?.contentScale || 1) * 100)} onChange={(event) => { const scale = +event.target.value / 100; if (scale >= .05 && scale <= 4) editing.frame(id, { presentation: { ...data.presentation, contentScale: scale } }); }} />%</label>
        <a href={`/dashboard/${encodeURIComponent(editing.workspace)}/${data.subgraph.boardId}`} aria-label="打开子画布" title="打开子画布"><ExternalLink size={15} /></a></>}

      </motion.div>
    </NodeToolbar>}</AnimatePresence>
    <TransformableNode {...nodeProps} hideStyleToolbar className={`${styles.frameNode} ${incoming ? styles.frameDropTarget : ""} ${outgoing ? styles.frameDropExit : ""}`}>
      {data.subgraph && data.presentation?.collapsed && <a className={styles.collapsedSubgraph} href={`/dashboard/${encodeURIComponent(editing.workspace)}/${data.subgraph.boardId}`} onPointerDown={(event) => event.stopPropagation()}><FoldVertical size={22} /><span>{data.title}</span><small>打开子画布</small></a>}
      {mode !== "hidden" && <div className={styles.frameLabel} style={{ scale: mode === "fixed" ? 1 / (zoom * (data.viewScale || 1)) : 1 }} title={data.title}>{data.title}</div>}
      {(incoming > 0 || outgoing > 0) && <div className={styles.frameDropHint} style={{ scale: 1 / (zoom * (data.viewScale || 1)) }}>{incoming > 0 ? `松开加入 · ${incoming} 项` : `松开移出 · ${outgoing} 项`}</div>}
      {(["top", "right", "bottom", "left"] as const).map((side) => <div key={side} className={`${styles.frameBorderHit} ${styles["frameBorder_" + side]}`} title="拖动分区，已有成员一起移动" />)}
      {directAnchors && <ContentHandles selected={!!selected} />}
      {data.ports?.map((port) => {
        // 只在同方向端口之间均分高度，index+1与length+1让首尾都留出边距。
        const peers = data.ports!.filter((item) => item.direction === port.direction);
        return <Handle key={port.id} id={`port:${port.id}`} type="source" position={port.direction === "input" ? Position.Left : Position.Right} className={styles.framePort} style={{ top: `${(peers.indexOf(port) + 1) / (peers.length + 1) * 100}%` }} isConnectableStart={selected && port.direction === "output"} isConnectableEnd={port.direction === "input"} title={port.direction === "input" ? "子画布输入" : "子画布输出"} />;
      })}
    </TransformableNode>
  </>;
}