// FPSMS-frontend/src/components/PickOrderSearch/PickExecutionForm.tsx
"use client";

import {
  Box,
  Button,
  Dialog,
  DialogActions,
  DialogContent,
  DialogTitle,
  FormControl,
  Grid,
  InputLabel,
  MenuItem,
  Select,
  TextField,
  Typography,
} from "@mui/material";
import { useCallback, useEffect, useState } from "react";
import { useTranslation } from "react-i18next";
import { GetPickOrderLineInfo, PickExecutionIssueData } from "@/app/api/pickOrder/actions";
import { fetchEscalationCombo } from "@/app/api/user/actions";
import { useRef } from "react";
import dayjs from 'dayjs';
import { INPUT_DATE_FORMAT } from "@/app/utils/formatUtil";

interface LotPickData {
  id: number; 
  lotId: number;
  lotNo: string;
  expiryDate: string;
  location: string;
  stockUnit: string;
  inQty: number;
  outQty: number;
  holdQty: number;
  totalPickedByAllPickOrders: number;
  availableQty: number;
  requiredQty: number;
  actualPickQty: number;
  lotStatus: string;
  lotAvailability: 'available' | 'insufficient_stock' | 'expired' | 'status_unavailable'|'rejected';
  stockOutLineId?: number;
  stockOutLineStatus?: string;
  stockOutLineQty?: number;
}

interface PickExecutionFormProps {
  open: boolean;
  onClose: () => void;
  onSubmit: (data: PickExecutionIssueData) => Promise<void>;
  selectedLot: LotPickData | null;
  selectedPickOrderLine: (GetPickOrderLineInfo & { pickOrderCode: string }) | null;
  pickOrderId?: number;
  pickOrderCreateDate: any;
  //  Remove these props since we're not handling normal cases
  // onNormalPickSubmit?: (lineId: number, lotId: number, qty: number) => Promise<void>;
  // selectedRowId?: number | null;
}

// 定义错误类型
interface FormErrors {
  actualPickQty?: string;
  missQty?: string;
  badItemQty?: string;
  issueRemark?: string;
  handledBy?: string;
}

const PickExecutionForm: React.FC<PickExecutionFormProps> = ({
  open,
  onClose,
  onSubmit,
  selectedLot,
  selectedPickOrderLine,
  pickOrderId,
  pickOrderCreateDate,
  //  Remove these props
  // onNormalPickSubmit,
  // selectedRowId,
}) => {
  const { t } = useTranslation();
  const [formData, setFormData] = useState<Partial<PickExecutionIssueData>>({});
  const [errors, setErrors] = useState<FormErrors>({});
  const [loading, setLoading] = useState(false);
  const [handlers, setHandlers] = useState<Array<{ id: number; name: string }>>([]);
  // 计算剩余可用数量
  const calculateRemainingAvailableQty = useCallback((lot: LotPickData) => {
    //  直接使用 availableQty，因为 API 没有返回 inQty 和 outQty
    return lot.availableQty || 0;
  }, []);
  const calculateRequiredQty = useCallback((lot: LotPickData) => {
    //  Use the original required quantity, not subtracting actualPickQty
    // The actualPickQty in the form should be independent of the database value
    return lot.requiredQty || 0;
  }, []);
  const remaining = selectedLot ? calculateRemainingAvailableQty(selectedLot) : 0;
  const req = selectedLot ? calculateRequiredQty(selectedLot) : 0;

  const ap = Number(formData.actualPickQty) || 0;
  const miss = Number(formData.missQty) || 0;
  const bad = Number(formData.badItemQty) || 0;

  // Max the user can type
  const maxPick = Math.min(remaining, req);
  const maxIssueTotal = Math.max(0, req - ap); // remaining room for miss+bad

  const clamp0 = (v: any) => Math.max(0, Number(v) || 0);
  // 获取处理人员列表
  useEffect(() => {
    const fetchHandlers = async () => {
      try {
        const escalationCombo = await fetchEscalationCombo();
        setHandlers(escalationCombo);
      } catch (error) {
        console.error("Error fetching handlers:", error);
      }
    };
    
    fetchHandlers();
  }, []);

    const initKeyRef = useRef<string | null>(null);

  useEffect(() => {
    if (!open || !selectedLot || !selectedPickOrderLine || !pickOrderId) return;

    // Only initialize once per (pickOrderLineId + lotId) while dialog open
    const key = `${selectedPickOrderLine.id}-${selectedLot.lotId}`;
    if (initKeyRef.current === key) return;

    const getSafeDate = (dateValue: any): string => {
      if (!dateValue) return dayjs().format(INPUT_DATE_FORMAT);
      try {
        const date = dayjs(dateValue);
        if (!date.isValid()) {
          return dayjs().format(INPUT_DATE_FORMAT);
        }
        return date.format(INPUT_DATE_FORMAT);
      } catch {
        return dayjs().format(INPUT_DATE_FORMAT);
      }
    };

    setFormData({
      pickOrderId: pickOrderId,
      pickOrderCode: selectedPickOrderLine.pickOrderCode,
      pickOrderCreateDate: getSafeDate(pickOrderCreateDate),
      pickExecutionDate: dayjs().format(INPUT_DATE_FORMAT),
      pickOrderLineId: selectedPickOrderLine.id,
      itemId: selectedPickOrderLine.itemId,
      itemCode: selectedPickOrderLine.itemCode,
      itemDescription: selectedPickOrderLine.itemName,
      lotId: selectedLot.lotId,
      lotNo: selectedLot.lotNo,
      storeLocation: selectedLot.location,
      requiredQty: selectedLot.requiredQty,
      actualPickQty: selectedLot.actualPickQty || 0,
      missQty: 0,
      badItemQty: 0,
      issueRemark: '',
      pickerName: '',
      handledBy: undefined,
    });

    initKeyRef.current = key;
  }, [open, selectedPickOrderLine?.id, selectedLot?.lotId, pickOrderId, pickOrderCreateDate]);
  // Mutually exclusive inputs: picking vs reporting issues

  const handleInputChange = useCallback((field: keyof PickExecutionIssueData, value: any) => {
    setFormData(prev => ({ ...prev, [field]: value }));
    // 清除错误
    if (errors[field as keyof FormErrors]) {
      setErrors(prev => ({ ...prev, [field]: undefined }));
    }
  }, [errors]);

 //  Update form validation to require either missQty > 0 OR badItemQty > 0
const validateForm = (): boolean => {
  const newErrors: FormErrors = {};
  const req = selectedLot?.requiredQty || 0;
  const ap = Number(formData.actualPickQty) || 0;
  const miss = Number(formData.missQty) || 0;
  const bad = Number(formData.badItemQty) || 0;
  const total = ap + miss + bad;

  // 1. 检查 actualPickQty 不能为负数
  if (ap < 0) {
    newErrors.actualPickQty = t('Qty cannot be negative');
  }
  
  // 2. 检查 actualPickQty 不能超过可用数量或需求数量
  if (ap > Math.min(req)) {
    newErrors.actualPickQty = t('Qty is not allowed to be greater than required/available qty');
  }
  
  // 3. 检查 missQty 和 badItemQty 不能为负数
  if (miss < 0) {
    newErrors.missQty = t('Invalid qty');
  }
  if (bad < 0) {
    newErrors.badItemQty = t('Invalid qty');
  }
  
  // 4. 🔥 关键验证：总和必须等于 Required Qty（不能多也不能少）
  if (total !== req) {
    const diff = req - total;
    const errorMsg = diff > 0 
      ? t('Total must equal Required Qty. Missing: {{diff}}', { diff })
      : t('Total must equal Required Qty. Exceeds by: {{diff}}', { diff: Math.abs(diff) });
    newErrors.actualPickQty = errorMsg;
    newErrors.missQty = errorMsg;
    newErrors.badItemQty = errorMsg;
  }
  
  // 5. 🔥 关键验证：如果只有 actualPickQty 有值，而 missQty 和 badItemQty 都为 0，不允许提交
  // 这意味着如果 actualPickQty < requiredQty，必须报告问题（missQty 或 badItemQty > 0）
  if (ap > 0 && miss === 0 && bad === 0 && ap < req) {
    newErrors.missQty = t('If Actual Pick Qty is less than Required Qty, you must report Missing Qty or Bad Item Qty');
    newErrors.badItemQty = t('If Actual Pick Qty is less than Required Qty, you must report Missing Qty or Bad Item Qty');
  }
  
  // 6. 如果所有值都为 0，不允许提交
  if (ap === 0 && miss === 0 && bad === 0) {
    newErrors.actualPickQty = t('Enter pick qty or issue qty');
    newErrors.missQty = t('Enter pick qty or issue qty');
  }
  
  // 7. 如果 actualPickQty = requiredQty，missQty 和 badItemQty 必须都为 0
  if (ap === req && (miss > 0 || bad > 0)) {
    newErrors.missQty = t('If Actual Pick Qty equals Required Qty, Missing Qty and Bad Item Qty must be 0');
    newErrors.badItemQty = t('If Actual Pick Qty equals Required Qty, Missing Qty and Bad Item Qty must be 0');
  }
  
  setErrors(newErrors);
  return Object.keys(newErrors).length === 0;
};

  const handleSubmit = async () => {
    // First validate the form
    if (!validateForm()) {
      console.error('Form validation failed:', errors);
      return; // Prevent submission, show validation errors
    }
    
    if (!formData.pickOrderId) {
      console.error('Missing pickOrderId');
      return;
    }

    setLoading(true);
    try {
      await onSubmit(formData as PickExecutionIssueData);
      // Automatically closed when successful (handled by onClose)
    } catch (error: any) {
      console.error('Error submitting pick execution issue:', error);
      // Show error message (can be passed to parent component via props or state)
      // 或者在这里显示 toast/alert
      alert(t('Failed to submit issue. Please try again.') + (error.message ? `: ${error.message}` : ''));
    } finally {
      setLoading(false);
    }
  };

  const handleClose = () => {
    setFormData({});
    setErrors({});
    onClose();
  };

  if (!selectedLot || !selectedPickOrderLine) {
    return null;
  }

  const remainingAvailableQty = calculateRemainingAvailableQty(selectedLot);
  const requiredQty = calculateRequiredQty(selectedLot);
  
  return (
    <Dialog open={open} onClose={handleClose} maxWidth="sm" fullWidth>
      <DialogTitle>
        {t('Pick Execution Issue Form')} {/*  Always show issue form title */}
      </DialogTitle>
      <DialogContent>
        <Box sx={{ mt: 2 }}>
          {/*  Add instruction text */}
          <Grid container spacing={2}>
            <Grid item xs={12}>
              <Box sx={{ p: 2, backgroundColor: '#fff3cd', borderRadius: 1, mb: 2 }}>
                <Typography variant="body2" color="warning.main">
                  <strong>{t('Note:')}</strong> {t('This form is for reporting issues only. You must report either missing items or bad items.')}
                </Typography>
              </Box>
            </Grid>
            
            {/*  Keep the existing form fields */}
            <Grid item xs={6}>
              <TextField
                fullWidth
                label={t('Required Qty')}
                value={selectedLot?.requiredQty || 0} 
                disabled
                variant="outlined"
               // helperText={t('Still need to pick')}
              />
            </Grid>
            
            <Grid item xs={6}>
              <TextField
                fullWidth
                label={t('Remaining Available Qty')}
                value={remainingAvailableQty}
                disabled
                variant="outlined"
               // helperText={t('Available in warehouse')}
              />
            </Grid>

            <Grid item xs={12}>
            <TextField
              fullWidth
              label={t('Actual Pick Qty')}
              type="number"
              value={formData.actualPickQty ?? ''}
              onChange={(e) => handleInputChange('actualPickQty', e.target.value === '' ? undefined : Math.max(0, Number(e.target.value) || 0))}
              error={!!errors.actualPickQty}
              helperText={errors.actualPickQty || `${t('Max')}: ${Math.min(remainingAvailableQty, selectedLot?.requiredQty || 0)}`}
              variant="outlined"
            />
            </Grid>

            <Grid item xs={12}>
            <TextField
              fullWidth
              label={t('Missing item Qty')}
              type="number"
              value={formData.missQty || 0}
              onChange={(e) => handleInputChange('missQty', e.target.value === '' ? undefined : Math.max(0, Number(e.target.value) || 0))}
              error={!!errors.missQty}
              variant="outlined"
              //disabled={(formData.actualPickQty || 0) > 0}
            />
            </Grid>

            <Grid item xs={12}>
            <TextField
              fullWidth
              label={t('Bad Item Qty')}
              type="number"
              value={formData.badItemQty || 0}
              onChange={(e) => handleInputChange('badItemQty', e.target.value === '' ? undefined : Math.max(0, Number(e.target.value) || 0))}
              error={!!errors.badItemQty}
              variant="outlined"
              //disabled={(formData.actualPickQty || 0) > 0}
            />
            </Grid>
            
            {/*  Show issue description and handler fields when bad items > 0 */}
            {(formData.badItemQty && formData.badItemQty > 0) ? (
              <>
                <Grid item xs={12}>
                  <TextField
                    fullWidth
                    id="issueRemark"
                    label={t('Issue Remark')}
                    multiline
                    rows={4}
                    value={formData.issueRemark || ''}
                    onChange={(e) => handleInputChange('issueRemark', e.target.value)}
                    error={!!errors.issueRemark}
                    helperText={errors.issueRemark}
                    //placeholder={t('Describe the issue with bad items')}
                    variant="outlined"
                  />
                </Grid>
                
                <Grid item xs={12}>
                  <FormControl fullWidth error={!!errors.handledBy}>
                    <InputLabel>{t('handler')}</InputLabel>
                    <Select
                      value={formData.handledBy ? formData.handledBy.toString() : ''}
                      onChange={(e) => handleInputChange('handledBy', e.target.value ? parseInt(e.target.value) : undefined)}
                      label={t('handler')}
                    >
                      {handlers.map((handler) => (
                        <MenuItem key={handler.id} value={handler.id.toString()}>
                          {handler.name}
                        </MenuItem>
                      ))}
                    </Select>
                    {errors.handledBy && (
                      <Typography variant="caption" color="error" sx={{ mt: 0.5, ml: 1.75 }}>
                        {errors.handledBy}
                      </Typography>
                    )}
                  </FormControl>
                </Grid>
              </>
            ) : (<></>)}
          </Grid>
        </Box>
      </DialogContent>
      <DialogActions>
        <Button onClick={handleClose} disabled={loading}>
          {t('Cancel')}
        </Button>
        <Button 
          onClick={handleSubmit} 
          variant="contained" 
          disabled={loading}
        >
          {loading ? t('submitting') : t('submit')}
        </Button>
      </DialogActions>
    </Dialog>
  );
};

export default PickExecutionForm;