/**
 * Pivot面板：长表→宽表
 * 从PivotDialog.tsx提取，作为TransformDialog的子组件
 */

import React, { useState } from 'react';
import { Select, Button, Alert, Checkbox, Radio, App } from 'antd';
import { ArrowLeftRight, Info } from 'lucide-react';

interface Props {
  columns: Array<{ id: string; name: string }>;
  sessionId: string | null;
  onApply: (newData: any[]) => void;
  onClose: () => void;
}

const PivotPanel: React.FC<Props> = ({
  columns,
  sessionId,
  onApply,
  onClose,
}) => {
  const { message } = App.useApp();
  const [indexColumn, setIndexColumn] = useState<string>('');
  const [pivotColumn, setPivotColumn] = useState<string>('');
  const [valueColumns, setValueColumns] = useState<string[]>([]);
  const [aggfunc, setAggfunc] = useState<'first' | 'last' | 'mean' | 'sum'>('first');
  const [loading, setLoading] = useState(false);
  const [keepUnusedColumns, setKeepUnusedColumns] = useState(false);
  const [unusedAggMethod, setUnusedAggMethod] = useState<'first' | 'mode' | 'mean'>('first');
  
  // 执行
  const handleApply = async () => {
    if (!sessionId) {
      message.error('Session ID不存在');
      return;
    }
    
    // 验证
    if (!indexColumn) {
      message.warning('请选择索引列（唯一标识列）');
      return;
    }
    
    if (!pivotColumn) {
      message.warning('请选择透视列（要变成列名的列）');
      return;
    }
    
    if (valueColumns.length === 0) {
      message.warning('请至少选择一个值列');
      return;
    }
    
    setLoading(true);
    
    try {
      const response = await fetch('/api/v1/dc/tool-c/quick-action', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          sessionId,
          action: 'pivot',
          params: {
            indexColumn,
            pivotColumn,
            valueColumns,
            aggfunc,
            keepUnusedColumns,
            unusedAggMethod,
          },
        }),
      });
      
      const result = await response.json();
      
      if (!result.success) {
        throw new Error(result.error || 'Pivot转换失败');
      }
      
      message.success('Pivot转换成功！');
      
      // 更新父组件数据
      if (result.data?.newDataPreview) {
        onApply(result.data.newDataPreview);
      }
      
      // 成功后关闭
      onClose();
    } catch (error: any) {
      message.error(error.message || '执行失败');
    } finally {
      setLoading(false);
    }
  };
  
  return (
    <div className="space-y-4 pb-4">
      {/* 说明 */}
      <Alert
        description={
          <div className="text-xs space-y-1">
            <div>• 将"一人多行"的纵向数据转为"一人一行"的横向数据</div>
            <div>• 典型场景：将随访数据（基线、随访2周、随访1个月）展开为独立列</div>
            <div>• 示例：Event_Name列的"基线"、"随访2周" → FMA_基线、FMA_随访2周</div>
          </div>
        }
        type="info"
        showIcon
        icon={<Info size={16} />}
        className="mb-4"
      />
      
      {/* 索引列 */}
      <div>
        <label className="text-sm font-medium text-slate-700 mb-1 block">
          索引列（唯一标识，如患者ID）：<span className="text-red-500">*</span>
        </label>
        <Select
          placeholder="选择唯一标识列"
          value={indexColumn || undefined}
          onChange={setIndexColumn}
          className="w-full"
          showSearch
          filterOption={(input, option) =>
            (option?.label ?? '').toLowerCase().includes(input.toLowerCase())
          }
          options={columns.map(col => ({ label: col.name, value: col.id }))}
        />
        <div className="text-xs text-slate-500 mt-1">
          每个唯一值将成为一行
        </div>
      </div>
      
      {/* 透视列 */}
      <div>
        <label className="text-sm font-medium text-slate-700 mb-1 block">
          透视列（要变成列名的列，如访视类型）：<span className="text-red-500">*</span>
        </label>
        <Select
          placeholder="选择透视列"
          value={pivotColumn || undefined}
          onChange={setPivotColumn}
          className="w-full"
          showSearch
          filterOption={(input, option) =>
            (option?.label ?? '').toLowerCase().includes(input.toLowerCase())
          }
          options={columns
            .filter(col => col.id !== indexColumn)
            .map(col => ({ label: col.name, value: col.id }))}
        />
        <div className="text-xs text-slate-500 mt-1">
          此列的不同值将成为新的列名后缀
        </div>
      </div>
      
      {/* 值列 */}
      <div>
        <label className="text-sm font-medium text-slate-700 mb-2 block">
          值列（要转置的数据列）：<span className="text-red-500">*</span>
        </label>
        <div className="border rounded-lg p-3 max-h-48 overflow-y-auto bg-slate-50">
          <Checkbox.Group
            value={valueColumns}
            onChange={setValueColumns}
            className="flex flex-col gap-2"
          >
            {columns
              .filter(col => col.id !== indexColumn && col.id !== pivotColumn)
              .map((col) => (
                <Checkbox key={col.id} value={col.id}>
                  {col.name}
                </Checkbox>
              ))}
          </Checkbox.Group>
        </div>
        <div className="text-xs text-slate-500 mt-1">
          可多选。每个值列会生成多个新列（如：FMA_基线、FMA_随访2周）
        </div>
      </div>
      
      {/* 聚合方式 */}
      <div>
        <label className="text-sm font-medium text-slate-700 mb-2 block">
          重复值处理方式：
        </label>
        <Radio.Group value={aggfunc} onChange={(e) => setAggfunc(e.target.value)}>
          <div className="space-y-2">
            <Radio value="first">
              <div className="ml-2">
                <span className="font-medium">取第一个值</span>
                <span className="text-xs text-slate-500 ml-2">（推荐）</span>
              </div>
            </Radio>
            <Radio value="last">
              <span className="ml-2 font-medium">取最后一个值</span>
            </Radio>
            <Radio value="mean">
              <span className="ml-2 font-medium">求平均值</span>
            </Radio>
            <Radio value="sum">
              <span className="ml-2 font-medium">求和</span>
            </Radio>
          </div>
        </Radio.Group>
      </div>
      
      {/* 高级选项 */}
      <div className="border-t pt-4">
        <div className="flex items-center gap-2 mb-3">
          <span className="text-sm font-medium text-slate-700">⚙️ 高级选项</span>
        </div>
        
        <Checkbox
          checked={keepUnusedColumns}
          onChange={(e) => setKeepUnusedColumns(e.target.checked)}
        >
          <span className="text-sm font-medium">保留未选择的列</span>
        </Checkbox>
        
        {keepUnusedColumns && (
          <div className="ml-6 mt-3 p-3 bg-slate-50 rounded-lg border border-slate-200">
            <label className="text-sm font-medium text-slate-700 mb-2 block">
              聚合方式：
            </label>
            <Radio.Group
              value={unusedAggMethod}
              onChange={(e) => setUnusedAggMethod(e.target.value)}
            >
              <div className="space-y-2">
                <Radio value="first">
                  <div className="ml-2">
                    <span className="font-medium text-sm">取第一个值</span>
                    <span className="text-xs text-slate-500 ml-2">（默认）</span>
                  </div>
                </Radio>
                <Radio value="mode">
                  <span className="ml-2 font-medium text-sm">取众数</span>
                </Radio>
                <Radio value="mean">
                  <div className="ml-2">
                    <span className="font-medium text-sm">取均值</span>
                    <span className="text-xs text-slate-500 ml-2">（仅数值列）</span>
                  </div>
                </Radio>
              </div>
            </Radio.Group>
          </div>
        )}
      </div>
      
      {/* 警告 */}
      <Alert
        description={
          <div className="text-xs space-y-1">
            <div>• Pivot操作会显著改变数据结构（行列转换）</div>
            <div>• 转换后列数可能大幅增加</div>
          </div>
        }
        type="warning"
        showIcon={false}
        className="bg-orange-50 border-orange-200"
      />
      
      {/* 底部按钮 */}
      <div className="flex justify-end gap-2 pt-4 border-t">
        <Button onClick={onClose}>
          取消
        </Button>
        <Button
          type="primary"
          onClick={handleApply}
          loading={loading}
          icon={<ArrowLeftRight size={16} />}
        >
          执行转换
        </Button>
      </div>
    </div>
  );
};

export default PivotPanel;