import { useState, useEffect, useRef, useCallback } from "react";
import { Modal, Collapse, Table, Input, Button, Space, Tag, App, Spin, Empty } from "antd";
import { SearchOutlined, PlusOutlined, MinusOutlined } from "@ant-design/icons";
import api from "../../services/api";
import { fetchMaterialGroups, fetchMaterialItems, type MaterialGroup, type MaterialItem } from "../../services/materialApi";

// ============================================================
// 类型
// ============================================================

interface Props {
  open: boolean;
  onClose: () => void;
  onCreated: () => void;
}

interface SelectedMaterial {
  material_id: string;
  material_name: string;
  spec_model: string;
  category: string;
  material_type: string;
}

// ============================================================
// 主组件
// ============================================================

export default function CreateProductDialog({ open, onClose, onCreated }: Props) {
  const { message } = App.useApp();

  // ---- 搜索 & 分组摘要 ----
  const [keyword, setKeyword] = useState("");
  const [summary, setSummary] = useState<MaterialGroup[]>([]);
  const [summaryLoading, setSummaryLoading] = useState(false);

  // ---- 手风琴展开 keys ----
  const [activeKeys, setActiveKeys] = useState<string[]>([]);

  // ---- 缓存 (对标老系统 groupCache / groupLoadingMap) ----
  const groupCache = useRef<Map<string, MaterialItem[]>>(new Map());
  const groupLoadingMap = useRef<Map<string, boolean>>(new Map());

  // ---- 选中物料 ----
  const [selected, setSelected] = useState<SelectedMaterial | null>(null);

  // ---- 表单 ----
  const [externalSerial, setExternalSerial] = useState("");
  const [orderNo, setOrderNo] = useState("");
  const [submitting, setSubmitting] = useState(false);
  const [createdSn, setCreatedSn] = useState<string | null>(null);

  // ---- 初始化 ----
  useEffect(() => {
    if (open) {
      setKeyword("");
      setActiveKeys([]);
      setSelected(null);
      setExternalSerial("");
      setOrderNo("");
      setCreatedSn(null);
      groupCache.current.clear();
      groupLoadingMap.current.clear();
      loadSummary();
    }
  }, [open]);

  // ============================================================
  // 数据加载
  // ============================================================

  /** 搜索分组摘要 */
  const loadSummary = useCallback(async (kw?: string) => {
    setSummaryLoading(true);
    try {
      const list = await fetchMaterialGroups(kw?.trim() || undefined);
      setSummary(list);
    } catch {
      message.error("加载物料分组失败");
    } finally {
      setSummaryLoading(false);
    }
  }, [message]);

  function handleSearch() {
    setActiveKeys([]);
    groupCache.current.clear();
    groupLoadingMap.current.clear();
    loadSummary(keyword.trim() || undefined);
  }

  // 防抖搜索：输入即搜，300ms 无键入后自动触发
  useEffect(() => {
    const timer = setTimeout(() => {
      handleSearch();
    }, 300);
    return () => clearTimeout(timer);
  }, [keyword]);

  /** 懒加载分组内物料 */
  async function loadGroupItems(category: string) {
    // 缓存命中 → 跳过
    if (groupCache.current.has(category)) return;
    // 正在加载 → 跳过
    if (groupLoadingMap.current.get(category)) return;

    groupLoadingMap.current.set(category, true);
    // 触发重渲染让 Table 显示 loading
    forceRefresh();

    try {
      const items = await fetchMaterialItems(category, keyword.trim() || undefined);
      groupCache.current.set(category, items);
    } catch {
      message.error(`加载 "${category}" 分组失败`);
    } finally {
      groupLoadingMap.current.set(category, false);
      forceRefresh();
    }
  }

  /** 强制刷新 — 因为 useRef 不会触发重渲染，借用 state 刷新 */
  const [, setTick] = useState(0);
  function forceRefresh() {
    setTick((t) => t + 1);
  }

  // ============================================================
  // 手风琴事件
  // ============================================================

  function handleCollapseChange(keys: string | string[]) {
    const newKeys = Array.isArray(keys) ? keys : [keys];
    setActiveKeys(newKeys);

    // 新展开的 panel → 懒加载
    const newlyOpened = newKeys.filter((k) => !activeKeys.includes(k));
    newlyOpened.forEach((cat) => loadGroupItems(cat));
  }

  function expandAll() {
    const all = summary.map((g) => g.category);
    setActiveKeys(all);
    all.forEach((cat) => loadGroupItems(cat));
  }

  function collapseAll() {
    setActiveKeys([]);
  }

  // ============================================================
  // 选择物料
  // ============================================================

  function handleSelect(item: MaterialItem) {
    setSelected({
      material_id: String(item.id),
      material_name: item.name,
      spec_model: item.spec,
      category: item.category,
      material_type: item.type,
    });
  }

  // ============================================================
  // 提交创建
  // ============================================================

  async function handleSubmit() {
    if (!selected) {
      message.warning("请选择一个物料");
      return;
    }
    setSubmitting(true);
    try {
      const { data } = await api.post("/products/", {
        material_id: selected.material_id,
        material_name: selected.material_name,
        spec_model: selected.spec_model,
        category: selected.category,
        material_type: selected.material_type,
        external_serial: externalSerial.trim() || null,
        order_no: orderNo.trim() || null,
      });
      setCreatedSn(data.serial_number);
      onCreated();
    } catch (err: any) {
      message.error(err?.response?.data?.detail ?? "创建失败");
    } finally {
      setSubmitting(false);
    }
  }

  // ============================================================
  // 表格列定义
  // ============================================================

  const columns = [
    {
      title: "名称",
      dataIndex: "name",
      key: "name",
      ellipsis: true,
      render: (v: string) => <span className="font-medium text-gray-800">{v}</span>,
    },
    {
      title: "规格",
      dataIndex: "spec",
      key: "spec",
      ellipsis: true,
    },
    {
      title: "类型",
      dataIndex: "type",
      key: "type",
      width: 80,
      render: (v: string) => <Tag>{v}</Tag>,
    },
    {
      title: "单位",
      dataIndex: "unit",
      key: "unit",
      width: 60,
    },
    {
      title: "操作",
      key: "action",
      width: 80,
      render: (_: unknown, record: MaterialItem) => (
        <Button
          type="link"
          size="small"
          onClick={(e) => {
            e.stopPropagation();
            handleSelect(record);
          }}
        >
          选择
        </Button>
      ),
    },
  ];

  // ============================================================
  // Collapse items 生成
  // ============================================================

  const collapseItems = summary.map((group) => {
    const items = groupCache.current.get(group.category);
    const isLoading = groupLoadingMap.current.get(group.category) === true;

    return {
      key: group.category,
      label: (
        <div className="flex items-center justify-between pr-2">
          <span className="text-sm font-medium text-gray-700">{group.category}</span>
          <Tag className="ml-2">{group.count}</Tag>
        </div>
      ),
      children: isLoading ? (
        <div className="flex items-center justify-center py-8">
          <Spin />
        </div>
      ) : items && items.length > 0 ? (
        <Table
          columns={columns}
          dataSource={items}
          rowKey="id"
          size="small"
          pagination={false}
          scroll={{ y: 240 }}
          onRow={(record) => ({
            className:
              selected?.material_id === String(record.id) ? "bg-blue-50" : "",
          })}
        />
      ) : (
        <Empty
          image={Empty.PRESENTED_IMAGE_SIMPLE}
          description="该分类下暂无物料"
          className="py-6"
        />
      ),
    };
  });

  // ============================================================
  // 打印标签
  // ============================================================

  function printCurrentQRCode() {
    const printArea = document.getElementById("label-print-area");
    if (!printArea) return;
    const printContent = printArea.innerHTML;

    const styles = Array.from(document.querySelectorAll("style, link[rel=\"stylesheet\"]"))
      .map(el => el.outerHTML)
      .join("");

    const iframe = document.createElement("iframe");
    iframe.style.position = "absolute";
    iframe.style.width = "0";
    iframe.style.height = "0";
    iframe.style.border = "none";
    document.body.appendChild(iframe);

    const doc = iframe.contentWindow!.document;
    doc.write(`
      <!DOCTYPE html>
      <html>
        <head><title>打印标签</title>${styles}
          <style>
            @page { size: auto; margin: 0mm; }
            body { margin: 0; padding: 0; background: #fff; display: flex; align-items: center; justify-content: center; min-height: 100vh; }
          </style>
        </head>
        <body><div style="width:100%;max-width:360px;margin:0 auto;padding:12px;box-sizing:border-box;background:#fff;font-family:monospace,'Helvetica Neue',sans-serif;">${printContent}</div></body>
      </html>
    `);
    doc.close();

    iframe.contentWindow!.onload = () => {
      iframe.contentWindow!.focus();
      iframe.contentWindow!.print();
      setTimeout(() => { document.body.removeChild(iframe); }, 1000);
    };
  }

  // ============================================================
  // 渲染
  // ============================================================

  return (
    <Modal
      title="创建产品"
      open={open}
      onCancel={onClose}
      width={720}
      footer={null}
      destroyOnHidden
    >
      {createdSn ? (
        /* ---- 成功页 ---- */
        <div className="py-4">
          <div id="label-print-area" style={{
            width: '100%', maxWidth: '360px', margin: '0 auto', padding: '12px',
            boxSizing: 'border-box', background: '#fff',
            fontFamily: 'monospace, "Helvetica Neue", Helvetica, sans-serif',
            border: '1px solid #e5e7eb'
          }}>
            <div style={{ width: '100%' }}>
              <div style={{ float: 'left', width: '110px', height: '110px', marginRight: '10px', marginBottom: '4px' }}>
                <img src={`/api/v1/products/qrcode/${createdSn}`} alt="QR"
                  style={{ width: '100%', height: '100%', objectFit: 'contain', display: 'block' }} />
              </div>
              <div style={{ fontSize: '13px', fontWeight: 900, color: '#000', lineHeight: '1.4', wordBreak: 'break-all' }}>
                <div style={{ marginBottom: '4px' }}>名: {selected?.material_name ?? ""}</div>
                <div style={{ marginBottom: '4px' }}>规: {selected?.spec_model ?? ""}</div>
                <div style={{ marginBottom: '4px' }}>单: {orderNo || "—"}</div>
              </div>
              <div style={{ clear: 'both' }}></div>
            </div>
            <div style={{ width: '100%', marginTop: '8px', paddingTop: '8px', borderTop: '2px solid #000',
              textAlign: 'center', fontSize: '16px', fontWeight: 900, color: '#000', letterSpacing: '1px' }}>
              码: {createdSn}
            </div>
          </div>
          <p className="mt-2 text-center text-sm text-green-600">产品创建成功！</p>
          <Space className="mt-3 flex justify-center">
            <Button type="primary" onClick={printCurrentQRCode}>🖨️ 直接打印标签</Button>
            <Button onClick={() => setCreatedSn(null)}>继续创建</Button>
          </Space>
        </div>
      ) : (
        /* ---- 表单 ---- */
        <div className="space-y-4">
          {/* ================================================================ */}
          {/* 物料选择区域 */}
          {/* ================================================================ */}
          <div>
            <div className="mb-2 flex items-center justify-between">
              <span className="text-sm font-medium text-gray-700">
                MOM 物料 <span className="text-red-500">*</span>
              </span>
              {!selected && (
                <Space size="small">
                  <Button size="small" icon={<PlusOutlined />} onClick={expandAll}>
                    全部展开
                  </Button>
                  <Button size="small" icon={<MinusOutlined />} onClick={collapseAll}>
                    全部折叠
                  </Button>
                </Space>
              )}
            </div>

            {/* 已选物料 → 折叠手风琴，展示紧凑标签 */}
            {selected ? (
              <div className="flex items-center justify-between rounded-lg border border-blue-200 bg-blue-50 px-4 py-3">
                <div>
                  <span className="text-base font-semibold text-blue-800">
                    {selected.material_name}
                  </span>
                  <div className="mt-0.5 flex gap-3 text-xs text-blue-500">
                    <span>规格: {selected.spec_model}</span>
                    <span>分类: {selected.category}</span>
                    <span>类型: {selected.material_type}</span>
                  </div>
                </div>
                <Button danger size="small" onClick={() => setSelected(null)}>
                  清除重选
                </Button>
              </div>
            ) : (
              <>
                {/* 搜索栏 */}
                <div className="mb-2 flex gap-2">
                  <Input
                    placeholder="搜索名称/规格…"
                    prefix={<SearchOutlined />}
                    value={keyword}
                    onChange={(e) => setKeyword(e.target.value)}
                    onPressEnter={handleSearch}
                    allowClear
                  />
                  <Button onClick={handleSearch}>搜索</Button>
                </div>

                {/* 手风琴 */}
                <div className="max-h-[360px] overflow-y-auto rounded-lg border border-gray-200">
                  {summaryLoading ? (
                    <div className="flex items-center justify-center py-16">
                      <Spin />
                    </div>
                  ) : summary.length === 0 ? (
                    <Empty
                      image={Empty.PRESENTED_IMAGE_SIMPLE}
                      description="暂无成品/半成品数据"
                      className="py-10"
                    />
                  ) : (
                    <Collapse
                      activeKey={activeKeys}
                      onChange={handleCollapseChange}
                      size="small"
                      ghost
                      items={collapseItems}
                    />
                  )}
                </div>
              </>
            )}
          </div>

          {/* ================================================================ */}
          {/* 系统唯一 ID（只读） */}
          {/* ================================================================ */}
          <div>
            <label className="mb-1 block text-sm font-medium text-gray-700">
              系统唯一 ID <span className="text-xs text-gray-400">(自动生成)</span>
            </label>
            <Input
              value="提交后自动生成 16 位 HEX"
              disabled
              className="font-mono text-gray-400"
            />
          </div>

          {/* 产品序列号（选填） */}
          <div>
            <label className="mb-1 block text-sm font-medium text-gray-700">
              产品序列号 <span className="text-xs text-gray-400">(选填)</span>
            </label>
            <Input
              value={externalSerial}
              onChange={(e) => setExternalSerial(e.target.value)}
              maxLength={64}
              placeholder="用户自定义序列号"
            />
          </div>

          {/* 所属订单（选填） */}
          <div>
            <label className="mb-1 block text-sm font-medium text-gray-700">
              所属订单 <span className="text-xs text-gray-400">(选填)</span>
            </label>
            <Input
              value={orderNo}
              onChange={(e) => setOrderNo(e.target.value)}
              maxLength={64}
              placeholder="自由键入订单号"
            />
          </div>

          {/* 提交 */}
          <Button
            type="primary"
            block
            size="large"
            loading={submitting}
            disabled={!selected}
            onClick={handleSubmit}
          >
            创建并生成二维码
          </Button>
        </div>
      )}
    </Modal>
  );
}