import { useEffect, useState } from 'react';
import { Alert, Button, Form, Input, InputNumber, Space, Typography, message } from 'antd';
import { DownOutlined, UpOutlined } from '@ant-design/icons';
import type { StorePackageItemDto } from '@dukang/shared-types';
import { STORE_PACKAGE_MAX_COUNT } from '@dukang/shared-types';
import { request } from '../lib/api';

type PackageRow = StorePackageItemDto;

function emptyRow(index = 0): PackageRow {
  return { name: '', price: '0', dishes: '', usableTime: '', otherNotes: '', sortOrder: index };
}

export default function AdminStorePackagesSection({ storeId }: { storeId: string }) {
  const [items, setItems] = useState<PackageRow[]>([emptyRow()]);
  const [collapsed, setCollapsed] = useState<Record<number, boolean>>({});
  const [loading, setLoading] = useState(true);
  const [saving, setSaving] = useState(false);

  useEffect(() => {
    setLoading(true);
    request<{ live: PackageRow[] }>(`/admin/stores/${storeId}/packages`)
      .then((data) => {
        setItems(
          data.live?.length
            ? data.live.map((p, i) => ({ ...p, price: String(p.price), sortOrder: i }))
            : [emptyRow()],
        );
      })
      .catch((e) => message.error(e instanceof Error ? e.message : '加载套餐失败'))
      .finally(() => setLoading(false));
  }, [storeId]);

  function updateAt(index: number, patch: Partial<PackageRow>) {
    setItems((prev) => prev.map((item, i) => (i === index ? { ...item, ...patch } : item)));
  }

  function addRow() {
    if (items.length >= STORE_PACKAGE_MAX_COUNT) return;
    setItems((prev) => [...prev, emptyRow(prev.length)]);
  }

  function removeAt(index: number) {
    setItems((prev) => prev.filter((_, i) => i !== index).map((item, i) => ({ ...item, sortOrder: i })));
    setCollapsed((prev) => {
      const next: Record<number, boolean> = {};
      Object.entries(prev).forEach(([k, v]) => {
        const i = Number(k);
        if (i < index) next[i] = v;
        else if (i > index) next[i - 1] = v;
      });
      return next;
    });
  }

  function toggleCollapse(index: number) {
    setCollapsed((prev) => ({ ...prev, [index]: !prev[index] }));
  }

  async function save() {
    const filled = items
      .map((item, index) => ({
        name: item.name.trim(),
        price: item.price.trim(),
        dishes: item.dishes.trim(),
        usableTime: item.usableTime?.trim() || null,
        otherNotes: item.otherNotes?.trim() || null,
        sortOrder: index,
      }))
      .filter((item) => item.name || item.dishes || item.price);

    for (let i = 0; i < filled.length; i++) {
      const item = filled[i];
      if (!item.name) {
        message.warning(`第 ${i + 1} 条套餐名称不能为空`);
        return;
      }
      if (!item.dishes) {
        message.warning(`第 ${i + 1} 条套餐菜品不能为空`);
        return;
      }
      const price = Number(item.price);
      if (!Number.isFinite(price) || price < 0) {
        message.warning(`第 ${i + 1} 条套餐价格须为非负数字`);
        return;
      }
    }

    setSaving(true);
    try {
      await request(`/admin/stores/${storeId}/packages`, {
        method: 'PUT',
        body: JSON.stringify({
          packages: filled.map((p) => ({ ...p, price: Number(p.price).toFixed(2) })),
        }),
      });
      message.success('套餐已保存并生效');
    } catch (e) {
      message.error(e instanceof Error ? e.message : '保存失败');
    } finally {
      setSaving(false);
    }
  }

  if (loading) {
    return <Typography.Text type="secondary">加载套餐中…</Typography.Text>;
  }

  return (
    <Form layout="vertical" requiredMark={false}>
      <Alert
        type="info"
        showIcon
        style={{ marginBottom: 16 }}
        message={`总部直存立即生效，无需审核。同一门店最多 ${STORE_PACKAGE_MAX_COUNT} 条套餐。`}
      />

      {items.map((item, index) => {
        const isCollapsed = !!collapsed[index];
        const displayName = item.name.trim() || `套餐 ${index + 1}`;
        return (
          <div
            key={index}
            style={{
              marginBottom: 16,
              padding: 16,
              border: '1px solid #f0f0f0',
              borderRadius: 8,
              background: '#fafafa',
            }}
          >
            <Space style={{ width: '100%', justifyContent: 'space-between', marginBottom: isCollapsed ? 0 : 12 }}>
              <Button
                type="text"
                icon={isCollapsed ? <DownOutlined /> : <UpOutlined />}
                onClick={() => toggleCollapse(index)}
                style={{ paddingLeft: 0, height: 'auto' }}
              >
                <Typography.Title level={5} style={{ margin: 0 }}>
                  {displayName}
                </Typography.Title>
              </Button>
              {items.length > 1 ? (
                <Button type="link" danger onClick={() => removeAt(index)}>
                  删除
                </Button>
              ) : null}
            </Space>

            {!isCollapsed ? (
              <>
                <Form.Item label="套餐名称" required style={{ marginBottom: 12 }}>
                  <Input
                    placeholder="如：套餐A"
                    value={item.name}
                    onChange={(e) => updateAt(index, { name: e.target.value })}
                  />
                </Form.Item>

                <Form.Item label="价格（元）" required style={{ marginBottom: 12 }}>
                  <InputNumber
                    min={0}
                    precision={2}
                    style={{ width: '100%' }}
                    addonAfter="元"
                    placeholder="198"
                    value={item.price === '' ? undefined : Number(item.price)}
                    onChange={(v) => updateAt(index, { price: v != null ? String(v) : '' })}
                  />
                </Form.Item>

                <Form.Item label="菜品" required style={{ marginBottom: 12 }}>
                  <Input.TextArea
                    rows={2}
                    placeholder="红烧肉、红烧鱼、油焖茄子"
                    value={item.dishes}
                    onChange={(e) => updateAt(index, { dishes: e.target.value })}
                  />
                </Form.Item>

                <Form.Item label="使用时间" style={{ marginBottom: 12 }}>
                  <Input
                    placeholder="节假日除外"
                    value={item.usableTime || ''}
                    onChange={(e) => updateAt(index, { usableTime: e.target.value })}
                  />
                </Form.Item>

                <Form.Item label="其他说明" style={{ marginBottom: 0 }}>
                  <Input
                    placeholder="不可叠加"
                    value={item.otherNotes || ''}
                    onChange={(e) => updateAt(index, { otherNotes: e.target.value })}
                  />
                </Form.Item>
              </>
            ) : null}
          </div>
        );
      })}

      {items.length < STORE_PACKAGE_MAX_COUNT ? (
        <Button onClick={addRow} style={{ marginBottom: 16 }}>
          添加套餐
        </Button>
      ) : null}

      <Typography.Paragraph type="secondary" style={{ marginBottom: 12 }}>
        修改后点击下方按钮保存，C 端将立即展示生效套餐。
      </Typography.Paragraph>

      <Button type="primary" loading={saving} onClick={() => void save()}>
        保存套餐
      </Button>
    </Form>
  );
}