'use client';

import { InventoryResult } from '@/app/api/inventory';
import { fetchInventoryQtyLots, InventoryQtyLotRow } from '@/app/api/inventory/actions';
import {
  Box,
  Button,
  CircularProgress,
  Dialog,
  DialogContent,
  DialogTitle,
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableRow,
  Typography,
} from '@mui/material';
import { useEffect, useRef, useState } from 'react';
import { useTranslation } from 'react-i18next';

const formatQty = (value: number) => {
  if (!Number.isFinite(value)) return '0';
  return Number.isInteger(value)
    ? value.toLocaleString()
    : value.toLocaleString(undefined, { maximumFractionDigits: 2 });
};

type Bucket = 'jo' | 'do' | 'other' | 'unavailable';

const reasonLabel = (t: (key: string) => string, row: InventoryQtyLotRow) => {
  const label =
    row.reason === 'expired'
      ? t('Expired lot')
      : row.reason === 'joHold'
        ? t('Jo hold qty')
        : row.reason === 'doHold'
          ? t('Do hold qty')
          : row.reason === 'otherHold' || row.reason === 'onHold'
            ? t('Other hold qty')
            : t('Unavailable lot');
  return row.detail ? `${label}：${row.detail}` : label;
};

const sumSource = (rows: InventoryQtyLotRow[], source: string) =>
  rows.reduce((sum, row) => (row.bucket === 'onHold' && row.source === source ? sum + Number(row.qty || 0) : sum), 0);

const InventoryQtyStory: React.FC<{ inventory: InventoryResult }> = ({ inventory }) => {
  const { t } = useTranslation('inventory');
  const onHand = Number(inventory.onHandQty ?? 0);
  const onHold = Number(inventory.onHoldQty ?? 0);
  const unavailable = Number(inventory.unavailableQty ?? 0);
  const available = Number(inventory.availableQty ?? onHand - onHold - unavailable);
  const shortUom = inventory.uomShortDesc || '';
  const [open, setOpen] = useState(false);
  const [bucket, setBucket] = useState<Bucket>('unavailable');
  const [loading, setLoading] = useState(false);
  const [rows, setRows] = useState<InventoryQtyLotRow[]>([]);
  const [splitReady, setSplitReady] = useState(false);
  const requestRef = useRef(0);

  useEffect(() => {
    setOpen(false);
    setRows([]);
    setSplitReady(onHold === 0);
    if (onHold === 0 || inventory.itemId == null) return;
    const requestId = ++requestRef.current;
    fetchInventoryQtyLots(inventory.itemId)
      .then((res) => {
        if (requestId !== requestRef.current) return;
        setRows(res ?? []);
        setSplitReady(true);
      })
      .catch(() => {
        if (requestId !== requestRef.current) return;
        setRows([]);
        setSplitReady(false);
      });
  }, [inventory.itemId, onHold]);

  const joHold = splitReady ? sumSource(rows, 'jo') : 0;
  const doHold = splitReady ? sumSource(rows, 'do') : 0;
  const otherHold = splitReady ? sumSource(rows, 'other') : 0;

  const openDetail = (next: Bucket) => {
    const qty =
      next === 'jo' ? joHold : next === 'do' ? doHold : next === 'other' ? otherHold : unavailable;
    if (qty === 0) return;
    setBucket(next);
    setOpen(true);
    if (rows.length > 0 || next !== 'unavailable') {
      setLoading(false);
      return;
    }
    const requestId = ++requestRef.current;
    setLoading(true);
    fetchInventoryQtyLots(inventory.itemId)
      .then((res) => {
        if (requestId !== requestRef.current) return;
        setRows(res ?? []);
      })
      .catch(() => {
        if (requestId !== requestRef.current) return;
        setRows([]);
      })
      .finally(() => {
        if (requestId === requestRef.current) setLoading(false);
      });
  };

  const visibleRows = rows.filter((row) =>
    bucket === 'unavailable' ? row.bucket === 'unavailable' : row.bucket === 'onHold' && row.source === bucket,
  );
  const title =
    bucket === 'jo'
      ? t('Jo hold qty')
      : bucket === 'do'
        ? t('Do hold qty')
        : bucket === 'other'
          ? t('Other hold qty')
          : t('Unavailable Qty');

  return (
    <Box sx={{ py: 1 }}>
      <Box sx={{ display: 'flex', flexWrap: 'wrap', alignItems: 'baseline', columnGap: 0.75, rowGap: 0.5 }}>
        <Typography variant="body2" component="span">
          {`${t('On Hand Qty')} ${formatQty(onHand)} −`}
        </Typography>
        {splitReady ? (
          <>
            <QtyLink
              label={`${t('Jo hold qty')} ${formatQty(joHold)}`}
              enabled={joHold !== 0}
              onClick={() => openDetail('jo')}
            />
            <Typography variant="body2" component="span">−</Typography>
            <QtyLink
              label={`${t('Do hold qty')} ${formatQty(doHold)}`}
              enabled={doHold !== 0}
              onClick={() => openDetail('do')}
            />
            {otherHold !== 0 && (
              <>
                <Typography variant="body2" component="span">−</Typography>
                <QtyLink
                  label={`${t('Other hold qty')} ${formatQty(otherHold)}`}
                  enabled
                  onClick={() => openDetail('other')}
                />
              </>
            )}
          </>
        ) : (
          <QtyLink
            label={`${t('On Hold Qty')} ${formatQty(onHold)}`}
            enabled={false}
            onClick={() => undefined}
          />
        )}
        <Typography variant="body2" component="span">−</Typography>
        <QtyLink
          label={`${t('Unavailable Qty')} ${formatQty(unavailable)}`}
          enabled={unavailable !== 0}
          onClick={() => openDetail('unavailable')}
        />
        <Typography variant="body2" component="span">
          {'= '}
          <Box component="span" sx={{ fontWeight: 700 }}>
            {`${t('Available Qty')} ${formatQty(available)}${shortUom}`}
          </Box>
        </Typography>
      </Box>
      <Dialog open={open} onClose={() => setOpen(false)} maxWidth="md" fullWidth>
        <DialogTitle>{`${title} · ${t('Qty lot detail')}`}</DialogTitle>
        <DialogContent>
          {loading ? (
            <Box sx={{ display: 'flex', justifyContent: 'center', py: 4 }}>
              <CircularProgress size={28} />
            </Box>
          ) : visibleRows.length === 0 ? (
            <Typography sx={{ py: 2 }}>{t('No qty lots')}</Typography>
          ) : (
            <Table size="small">
              <TableHead>
                <TableRow>
                  <TableCell>{t('Lot No')}</TableCell>
                  <TableCell>{t('Expiry Date')}</TableCell>
                  <TableCell align="right">{t('Qty')}</TableCell>
                  <TableCell>{t('Warehouse')}</TableCell>
                  <TableCell>{t('Why')}</TableCell>
                </TableRow>
              </TableHead>
              <TableBody>
                {visibleRows.map((row) => (
                  <TableRow key={`${row.bucket}-${row.source}-${row.lotLineId}-${row.detail}`}>
                    <TableCell sx={{ whiteSpace: 'nowrap' }}>{row.lotNo}</TableCell>
                    <TableCell sx={{ whiteSpace: 'nowrap' }}>{row.expiryDate}</TableCell>
                    <TableCell align="right" sx={{ whiteSpace: 'nowrap' }}>{formatQty(row.qty)}</TableCell>
                    <TableCell sx={{ whiteSpace: 'nowrap' }}>{row.warehouseCode}</TableCell>
                    <TableCell>{reasonLabel(t, row)}</TableCell>
                  </TableRow>
                ))}
              </TableBody>
            </Table>
          )}
        </DialogContent>
      </Dialog>
    </Box>
  );
};

const QtyLink = ({
  label,
  enabled,
  onClick,
}: {
  label: string;
  enabled: boolean;
  onClick: () => void;
}) => {
  if (!enabled) {
    return (
      <Typography variant="body2" component="span">
        {label}
      </Typography>
    );
  }
  return (
    <Button
      variant="text"
      onClick={onClick}
      sx={{
        minWidth: 0,
        p: 0,
        textTransform: 'none',
        fontWeight: 400,
        fontSize: '0.875rem',
        lineHeight: 1.43,
        verticalAlign: 'baseline',
      }}
    >
      {label}
    </Button>
  );
};

export default InventoryQtyStory;