/**
 * 流转树双模式可视化 — 焦点模式 + 全景模式
 */
import { memo, useMemo, useState, useEffect } from "react";
import { Image } from "antd";
import { FileText, Package, User, X } from "lucide-react";
import type { TaskResponse } from "../../types/api";
import { TASK_STATUS } from "../../types/api";
import { getStatusConfig } from "../../constants/task";
import type { ModalTarget } from "./TaskTreeViewer";

// ============================================================
// 工具
// ============================================================
function fmtTime(d: string | null) { if (!d) return ""; const dt = new Date(d); const pad = (n: number) => String(n).padStart(2, "0"); return `${dt.getFullYear()}-${pad(dt.getMonth() + 1)}-${pad(dt.getDate())} ${pad(dt.getHours())}:${pad(dt.getMinutes())}`; }
function isMain(t: TaskResponse) { return !t.parent_task_id || t.task_type === "TRANSFER" || t.task_type === "RECOVERY" || t.task_type === "WAREHOUSE"; }
function active(s: string) { return s === "WIP" || s === "PENDING"; }
/** 微型右箭头 SVG */
function ArrowRight({ color = "#9ca3af", big }: { color?: string; big?: boolean }) {
  return <svg className={`shrink-0 ${big ? "h-4 w-4" : "h-3 w-3"}`} viewBox="0 0 8 8"><polygon points="0,0 8,4 0,8" fill={color} /></svg>;
}
/** 微型左箭头 SVG */
function ArrowLeft({ color = "#9ca3af", big }: { color?: string; big?: boolean }) {
  return <svg className={`shrink-0 ${big ? "h-4 w-4" : "h-3 w-3"}`} viewBox="0 0 8 8"><polygon points="8,0 0,4 8,8" fill={color} /></svg>;
}
function parseImages(s: any): string[] {
  if (!s) return [];
  if (Array.isArray(s)) return s;                      // Pydantic 序列化后的数组
  if (typeof s === "string") { try { return JSON.parse(s); } catch { return []; } }
  return [];
}
function imageUrl(u: string) {
  if (!u) return "";
  if (u.startsWith("http")) return u;      // 已是完整绝对地址（含跨域域名），直接用
  const base = (import.meta.env.VITE_API_BASE_URL || "").replace(/\/+$/, ""); // 去掉末尾斜杠
  const path = u.startsWith("/") ? u : "/" + u;
  // 后端图片固定返回 /api/v1/upload/files/... 这类 /api/ 开头的相对路径，
  // 需拼上 base 才能访问到后端；同时避免重复前缀：
  //  - base 为纯域名（如 https://track_back.iris-rs.cn）→ 正常 base + path
  //  - base 以 /api 或 /api/v1 结尾 → 先剥掉该段，否则会拼出 /api/api/ 或 /api/v1/api/v1
  if (path.startsWith("/api/")) {
    const origin = base.replace(/\/api(\/v\d+)?$/, "");
    return origin + path;
  }
  return base + path;
}

const ALL_TASKS = new Set<TaskResponse>();
function collectAll(tasks: TaskResponse[]) { tasks.forEach(t => { ALL_TASKS.add(t); if (t.child_tasks) collectAll(t.child_tasks); }); }
function findParent(child: TaskResponse): TaskResponse | undefined { for (const t of ALL_TASKS) { if (t.id === child.parent_task_id) return t; } return undefined; }

// ============================================================
// 尺寸映射表（sm=现状小卡片，lg=弹窗放大）
// ============================================================
const SIZE_MAP = {
  sm: {
    card: "w-44 p-2.5 shadow-sm",
    badge: "-top-1.5 right-2 px-1.5 py-px text-[8px]",
    title: "mt-1 text-xs",
    metaRow: "mt-1",
    status: "px-1.5 py-px text-[8px]",
    assignee: "text-[9px]",
    time: "mt-1 text-[8px]",
    sub: "mt-1 text-[8px]",
    btnRow: "mt-1.5 pt-1.5",
    btn: "py-0.5 text-[8px]",
    record: "mt-1 px-1.5 py-0.5 text-[8px]",
    recordIcon: "h-2.5 w-2.5",
  },
  lg: {
    card: "w-72 p-4 shadow-md",
    badge: "-top-2 right-3 px-2 py-0.5 text-xs",
    title: "mt-1.5 text-base",
    metaRow: "mt-2",
    status: "px-2 py-0.5 text-xs",
    assignee: "text-sm",
    time: "mt-2 text-xs",
    sub: "mt-1.5 text-xs",
    btnRow: "mt-2.5 pt-2.5",
    btn: "py-1.5 text-sm",
    record: "mt-2 px-2.5 py-1 text-xs",
    recordIcon: "h-4 w-4",
  },
} as const;

// ============================================================
// 极简卡片
// ============================================================
const SlimCard = memo(function SlimCard({
  task, assigneeName, active, legacy, onAction, currentUser, onViewRecords, rootMainId, size = "sm", assigneeNames,
}: {
  task: TaskResponse; assigneeName?: string; active: boolean; legacy?: boolean;
  onAction: (t: ModalTarget) => void; currentUser?: { username?: string; role?: string } | null;
  onViewRecords?: (t: TaskResponse) => void;
  rootMainId?: string;
  size?: "sm" | "lg";
  assigneeNames?: Record<string, string>;
}) {
  const cfg = getStatusConfig(task.status);
  const sz = SIZE_MAP[size];
  const isOwner = !!(currentUser?.username && task.assignee_id === currentUser.username);
  const isManager = currentUser?.role === "SUPER_ADMIN" || currentUser?.role === "SUPERVISOR";
  const main = isMain(task);
  const isNestedSpawn = !main && rootMainId && task.parent_task_id !== rootMainId && !!task.parent_task_id;
  // 📥 在库/入库任务：显示"谁转入在库"（创建该任务的人）
  const isWarehouse = !!(
    task.task_name?.includes("在库") ||
    task.task_name?.includes("入库") ||
    task.assignee_id === "virtual_warehouse"
  );

  return (
    <div className={`relative shrink-0 rounded-lg border bg-white ${sz.card} ${active ? "border-blue-400 ring-1 ring-blue-100" : "border-gray-200 opacity-75"} ${legacy ? "border-orange-300 animate-pulse" : ""} ${task.is_rework ? "border-l-red-500 border-l-2" : ""}`}>
      {/* 左上角：主线/分支标签 + 状态标签并排 */}
      <div className={`${sz.metaRow} flex items-center gap-1`}>
        <span className={`rounded px-1.5 py-px font-bold text-white ${main ? "bg-blue-500" : "bg-purple-500"}`}>{main ? "主线" : "分支"}</span>
        <span className={`rounded-full ${sz.status} font-medium ${cfg.bg} ${cfg.text}`}>{cfg.label}</span>
      </div>
      <p className={`${sz.title} font-bold text-gray-800 truncate`}>{task.task_name}</p>
      {/* 操作人（带用户图标）+ 在库转入人；仓储任务防御性渲染为系统节点 */}
      <div className={`${sz.metaRow} flex items-center gap-1`}>
        {(() => {
          const isSystemTask = task.task_name?.includes("扫码") || task.task_type === "WAREHOUSE";
          if (isSystemTask) {
            // ★ 仓储系统任务：不请求用户数据，直接显示系统图标 + 固定名（assignee_id 为 null 不报错）
            return (
              <span className={`${sz.assignee} text-gray-400 truncate inline-flex items-center gap-0.5`}>
                <Package className="h-2.5 w-2.5 shrink-0" />MOM 仓储系统
              </span>
            );
          }
          if (isWarehouse && task.assignee_id) {
            return (
              <span className={`${sz.sub} text-emerald-600`}>📥 转入在库: {assigneeName || task.assignee_id}</span>
            );
          }
          return (
            <span className={`${sz.assignee} text-gray-400 truncate inline-flex items-center gap-0.5`}>
              <User className="h-2.5 w-2.5 shrink-0" />{assigneeName || task.assignee_id || "—"}
            </span>
          );
        })()}
      </div>
      {/* 单行时间（精确到分钟） */}
      <p className={`${sz.time} text-gray-300`}>
        ⏰ {fmtTime(task.created_at)}
        {task.completed_at ? ` → ${fmtTime(task.completed_at)}` : " → 至今"}
      </p>
      {legacy && <p className={`${sz.sub} text-orange-500`}>源自: {assigneeName || (findParent(task)?.assignee_id) || "历史任务"}</p>}
      {isNestedSpawn && <p className={`${sz.sub} text-purple-500`}>协助: {findParent(task)?.assignee_id || "—"}</p>}
      {/* 操作按钮 */}
      {active && isOwner && (
        <div className={`${sz.btnRow} flex gap-1 border-t border-gray-100`}>
          {task.status?.toUpperCase() === TASK_STATUS.PENDING && <button onClick={() => onAction({ task, action: "receive" })} className={`flex-1 rounded border border-blue-200 bg-blue-50 ${sz.btn} text-blue-600`}>接收</button>}
          {task.status?.toUpperCase() !== TASK_STATUS.PENDING && <button onClick={() => onAction({ task, action: "transfer" })} className={`flex-1 rounded border border-green-200 bg-green-50 ${sz.btn} text-green-600`}>转交</button>}
          <button onClick={() => onAction({ task, action: "reject" })} className={`flex-1 rounded border border-red-200 bg-red-50 ${sz.btn} text-red-500`}>驳回</button>
        </div>
      )}
      {active && !isOwner && isManager && (
        <div className={`${sz.btnRow} flex gap-1 border-t border-orange-100`}>
          <button onClick={() => onAction({ task, action: "reject" })} className={`flex-1 rounded border border-orange-200 bg-orange-50 ${sz.btn} text-orange-600`}>强制驳回</button>
          <button onClick={() => onAction({ task, action: "transfer" })} className={`flex-1 rounded border border-orange-200 bg-orange-50 ${sz.btn} text-orange-600`}>强制转交</button>
        </div>
      )}
      {/* 操作日志：全行蓝色横条，铺满卡片宽度（含 padding+border），整条可点击 */}
      {task.records && task.records.length > 0 && (
        <div
          onClick={(e) => { e.stopPropagation(); onViewRecords?.(task); }}
          className={`${size === "lg" ? "-mx-[17px] -mb-[17px]" : "-mx-[11px] -mb-[11px]"} mt-3 py-1.5 bg-blue-50 text-blue-600 text-center text-sm font-medium cursor-pointer transition-colors hover:bg-blue-100 border-t border-blue-100 rounded-b-lg`}
        >
          查看操作日志 ({task.records.length}条) <span className="font-bold text-blue-700">›</span>
        </div>
      )}
    </div>
  );
});

// ============================================================
// 主视图
// ============================================================
interface TaskFlowViewProps {
  tasks: TaskResponse[]; onAction: (t: ModalTarget) => void;
  currentUser?: { username?: string; role?: string } | null;
  assigneeNames?: Record<string, string>;
  size?: "sm" | "lg";
}

export const TaskFlowView = memo(function TaskFlowView({ tasks, onAction, currentUser, assigneeNames, size = "sm" }: TaskFlowViewProps) {
  const [showFullMap, setShowFullMap] = useState(false);
  const [recordsTask, setRecordsTask] = useState<TaskResponse | null>(null);

  // 🚀 记录弹窗打开时锁定背景滚动（防止滚动穿透），关闭时恢复
  useEffect(() => {
    if (!recordsTask) return;
    const prev = document.body.style.overflow;
    document.body.style.overflow = "hidden";
    return () => { document.body.style.overflow = prev; };
  }, [recordsTask]);

  // 数据分类 — 🚀 仅根级主干作为垂直时间线节点，子节点通过 childMap 分支递归渲染
  const { allMains, childMap } = useMemo(() => {
    ALL_TASKS.clear(); if (tasks.length) collectAll(tasks);
    const all = Array.from(ALL_TASKS);
    // 🚀 收集所有主线任务（全部进入中央垂直主轴）
    const mains: TaskResponse[] = [];
    for (const t of all) {
      if (isMain(t)) mains.push(t);
    }
    mains.sort((a, b) => new Date(a.created_at).getTime() - new Date(b.created_at).getTime());
    // 🚀 构建全局 childMap（按 parent_task_id 索引直接子节点，保留真实树结构）
    const childMap: Record<string, TaskResponse[]> = {};
    for (const t of all) {
      const pid = t.parent_task_id || '';
      if (!childMap[pid]) childMap[pid] = [];
      childMap[pid].push(t);
    }
    Object.values(childMap).forEach(arr => arr.sort((a, b) => new Date(a.created_at).getTime() - new Date(b.created_at).getTime()));
    return { allMains: mains, childMap };
  }, [tasks]);

  // 🚀 递归渲染分支节点 — 每个节点从自己的 childMap 获取直系子孙，保持树结构不断裂
  const renderBranch = (node: TaskResponse, side: 'left' | 'right', isLegacy: boolean, rootMainId: string): React.JSX.Element => {
    const kids = childMap[node.id] || [];
    const big = size === "lg";
    const arrow = side === 'left'
      ? (<div className="flex items-center"><ArrowLeft color={isLegacy ? "#fdba74" : "#9ca3af"} big={big} /><div className={`${big ? "w-10 border-t-[3px]" : "w-6 border-t-2"} ${isLegacy ? "border-dashed border-orange-300" : "border-solid border-gray-400"}`} /></div>)
      : (<div className="flex items-center"><div className={`${big ? "w-10 border-t-[3px]" : "w-6 border-t-2"} ${isLegacy ? "border-dashed border-orange-300" : "border-solid border-gray-400"}`} /><ArrowRight color={isLegacy ? "#fdba74" : "#9ca3af"} big={big} /></div>);
    const card = <SlimCard task={node} active={active(node.status)} legacy={isLegacy} assigneeName={assigneeNames?.[node.assignee_id || ""]} onAction={onAction} currentUser={currentUser} onViewRecords={setRecordsTask} rootMainId={rootMainId} size={size} assigneeNames={assigneeNames} />;
    const kidsContainer = kids.length > 0 ? (
      <div className={`flex flex-col gap-2 ${side === 'left' ? 'items-end' : 'items-start'}`}>
        {kids.map(k => renderBranch(k, side, isLegacy, rootMainId))}
      </div>
    ) : null;
    return (
      <div key={node.id} className="flex flex-row items-center gap-1">
        {side === 'left' && kidsContainer}
        {side === 'left' && card}
        {arrow}
        {side === 'right' && card}
        {side === 'right' && kidsContainer}
      </div>
    );
  };

  // 🚀 焦点模式 vs 全景模式：共用同一套垂直时间线布局，仅数据过滤不同
  const visibleMains = useMemo(() => {
    if (showFullMap) return allMains;
    // 焦点模式：保留自身活跃的主线，或含活跃分支（后代）的主线，
    // 避免「主线已完成、但并发协助分支仍在进行中」时整条分支被错误隐藏
    const hasActiveDescendant = (node: TaskResponse): boolean => {
      const kids = childMap[node.id] || [];
      return kids.some(k => active(k.status) || hasActiveDescendant(k));
    };
    return allMains.filter(t => active(t.status) || hasActiveDescendant(t));
  }, [allMains, childMap, showFullMap]);

  return (
    <div>
      {/* 模式切换 */}
      <div className="mb-3 flex justify-center">
        <button onClick={() => setShowFullMap(!showFullMap)}
          className={`rounded-full bg-gray-100 font-medium text-gray-600 hover:bg-gray-200 transition-colors ${size === "lg" ? "px-5 py-2 text-sm" : "px-4 py-1.5 text-xs"}`}>
          {showFullMap ? "🔼 收起，仅看当前并发任务" : "👁️ 展开全景流转树 (查看包含已完工在内的完整历史)"}
        </button>
      </div>

      {/* ─── 统一垂直时间线布局（焦点/全景共用） ─── */}
      <div className="space-y-6">
        {visibleMains.map((mainTask, mainIdx) => {
          // 🔧 侧翼严格过滤：主线归主轴，仅 SPAWN 协助分支进入左右翼
          const directChildren = (childMap[mainTask.id] || []).filter(c => !isMain(c));
          const hasLegacyActive = directChildren.some(c => !isMain(c) && !active(mainTask.status));
          const leftDirect = directChildren.filter((_, i) => i % 2 === 0);
          const rightDirect = directChildren.filter((_, i) => i % 2 === 1);
          const lineStyle = hasLegacyActive && !active(mainTask.status);

          return (
            <div key={mainTask.id} className="relative">
              {/* 中央垂直线：按行渲染；首行从卡片中间起，末行到卡片中间止，避免冒出/多截 */}
              <div
                className={`absolute left-1/2 -translate-x-1/2 z-0 bg-gray-200 ${size === "lg" ? "w-1" : "w-0.5"}`}
                style={{
                  top: mainIdx === 0 ? "50%" : 0,
                  bottom: mainIdx === visibleMains.length - 1 ? "50%" : 0,
                }}
              />
              <div className="flex flex-row items-start w-full">
                {/* 左翼 — 递归渲染，子子孙孙向外延伸 */}
                <div className="flex-1 flex flex-col items-end justify-center gap-2 pr-2">
                  {leftDirect.map(c => renderBranch(c, 'left', lineStyle, mainTask.id))}
                </div>
                {/* 中央 */}
                <div className="shrink-0 z-10 relative">
                  <SlimCard task={mainTask} active={active(mainTask.status)}
                    assigneeName={assigneeNames?.[mainTask.assignee_id || ""]} onAction={onAction} currentUser={currentUser} onViewRecords={setRecordsTask} size={size} assigneeNames={assigneeNames} />
                  {active(mainTask.status) && (
                    <div className={`absolute -top-1 -left-1 rounded-full bg-green-400 border-2 border-white ${size === "lg" ? "h-4 w-4" : "h-3 w-3"}`} />
                  )}
                </div>
                {/* 右翼 — 递归渲染，子子孙孙向外延伸 */}
                <div className="flex-1 flex flex-col items-start justify-center gap-2 pl-2">
                  {rightDirect.map(c => renderBranch(c, 'right', lineStyle, mainTask.id))}
                </div>
              </div>

              {visibleMains.indexOf(mainTask) < visibleMains.length - 1 && (
                <div className="flex justify-center py-2">
                  <span className={`text-gray-300 ${size === "lg" ? "text-sm" : "text-[10px]"}`}>▼</span>
                </div>
              )}
            </div>
          );
        })}
        {visibleMains.length === 0 && (
          <p className={`text-center text-gray-400 py-8 ${size === "lg" ? "text-sm" : "text-xs"}`}>
            {showFullMap ? "暂无流转记录" : "当前无活跃主线任务"}
          </p>
        )}
      </div>

      {/* 记录弹窗 */}
      {recordsTask && (
        <div className="fixed inset-0 z-[60] flex items-center justify-center">
          <div className="absolute inset-0 bg-black/40 backdrop-blur-sm" onClick={() => setRecordsTask(null)} />
          <div className={`relative z-10 mx-4 max-h-[80vh] w-full overflow-y-auto rounded-xl bg-white shadow-2xl ${size === "lg" ? "max-w-2xl p-6" : "max-w-md p-5"}`}>
            <div className={`mb-3 flex items-center justify-between`}><h3 className={`font-bold ${size === "lg" ? "text-lg" : "text-sm"}`}>提交记录 — {recordsTask.task_name}</h3><button onClick={() => setRecordsTask(null)} className="rounded p-1 text-gray-400 hover:bg-gray-100"><X className="h-4 w-4" /></button></div>
            {(recordsTask.records || []).length === 0 ? <p className="py-8 text-center text-sm text-gray-400">暂无记录</p> :
              <div className="space-y-2">{[...recordsTask.records!].reverse().map((r, i) => (
                <div key={r.id} className="flex gap-2">
                  <div className={`mt-1.5 h-2 w-2 shrink-0 rounded-full ${i === 0 ? "bg-blue-500" : "bg-gray-300"}`} />
                  <div className="flex-1 rounded bg-gray-50 px-3 py-2"><p className={`text-gray-400 ${size === "lg" ? "text-xs" : "text-[10px]"}`}>{fmtTime(r.created_at)}</p>
                    {r.remark && <p className={`mt-0.5 text-gray-700 ${size === "lg" ? "text-sm" : "text-xs"}`}>{r.remark}</p>}
                    {(() => { const imgs = parseImages(r.images); if (!imgs.length) return null; return (
                      <Image.PreviewGroup>
                        <div className="mt-1 flex gap-1 flex-wrap">{imgs.map((img, j) => <Image key={j} src={imageUrl(img)} width={size === "lg" ? 96 : 56} height={size === "lg" ? 96 : 56} className="rounded border object-cover" style={{ objectFit: "cover" }} />)}</div>
                      </Image.PreviewGroup>
                    ); })()}
                  </div>
                </div>
              ))}</div>}
          </div>
        </div>
      )}
    </div>
  );
});

export default TaskFlowView;