'use client';
import { InventoryLotLineResult, InventoryResult } from '@/app/api/inventory';
import { useTranslation } from 'react-i18next';
import SearchBox, { Criterion } from '../SearchBox';
import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
import { uniq, uniqBy } from 'lodash';
import InventoryTable from './InventoryTable';
import { defaultPagingController } from '../SearchResults/SearchResults';
import InventoryLotLineTable from './InventoryLotLineTable';
import InventoryItemLedger from './InventoryItemLedger';
import InventoryItemUom from './InventoryItemUom';
import InventoryQtyStory from './InventoryQtyStory';
import { useQrCodeScannerContext } from '@/components/QrCodeScannerProvider/QrCodeScannerProvider';
import {
  analyzeQrCode,
  SearchInventory,
  SearchInventoryLotLine,
  fetchInventoriesLatest,
  fetchInventoryLotLines,
} from '@/app/api/inventory/actions';
import { PrinterCombo } from '@/app/api/settings/printer';
import { fetchItemsByPage } from '@/app/api/settings/item/actions';
import { useSession } from 'next-auth/react';
import { AUTH, hasAbility } from '@/authorities';
import { Button, Box, Tab, Tabs } from '@mui/material';

interface Props {
  inventories: InventoryResult[];
  printerCombo?: PrinterCombo[];
}

type SearchQuery = Partial<
  Omit<
    InventoryResult,
    | "id"
    | "qty"
    | "uomCode"
    | "uomUdfudesc"
    | "uomId"
    | "stockUomId"
    | "stockUomCode"
    | "germPerSmallestUnit"
    | "qtyPerSmallestUnit"
    | "itemSmallestUnit"
    | "price"
    | "description"
    | "category"
  >
>;
type SearchParamNames = keyof SearchQuery;

type ItemLookupRow = {
  id: number;
  code: string;
  name: string;
  type?: string;
  uom?: string;
  uomDesc?: string;
  purchaseUnit?: string;
};

const extractItemRecords = (res: unknown): ItemLookupRow[] => {
  if (!res) return [];
  if (Array.isArray(res)) return res as ItemLookupRow[];
  if (typeof res === 'object' && Array.isArray((res as { records?: unknown }).records)) {
    return (res as { records: ItemLookupRow[] }).records;
  }
  return [];
};

/** FP-MTMS Version Checklist | Functions Ref. No. 18 | v1.0.5 | 2026-09-21 */
const InventorySearch: React.FC<Props> = ({ inventories, printerCombo }) => {
  const { t } = useTranslation(['inventory', 'common', 'item']);
  const { data: session } = useSession();
  const abilities = session?.abilities ?? session?.user?.abilities ?? [];
  const canStockAdjust = hasAbility(abilities, AUTH.INVENTORY_ADJUST);
  const searchInFlightRef = useRef(false);

  const buildSyntheticInventory = useCallback((item: ItemLookupRow): InventoryResult => {
    const uom = item.uomDesc || item.uom || item.purchaseUnit || '';
    return {
      id: 0,
      itemId: Number(item.id),
      itemCode: item.code,
      itemName: item.name,
      itemType: item.type || 'mat',
      onHandQty: 0,
      onHoldQty: 0,
      unavailableQty: 0,
      availableQty: 0,
      uomCode: item.uom || uom,
      uomUdfudesc: uom,
      uomShortDesc: item.uom || uom,
      qtyPerSmallestUnit: 1,
      baseUom: uom,
      price: 0,
      currencyName: '',
      status: 'active',
      latestMarketUnitPrice: undefined,
      latestMupUpdatedDate: undefined,
    };
  }, []);

  const lookupItemsByCodeOrName = useCallback(async (code?: string, name?: string) => {
    const trimmedCode = code?.trim();
    const trimmedName = name?.trim();
    if (!trimmedCode && !trimmedName) return [];
    const params: Record<string, string | number> = { pageSize: 50, pageNum: 1 };
    if (trimmedCode) params.code = trimmedCode;
    else params.name = trimmedName as string;
    const itemRes = await fetchItemsByPage(params);
    return extractItemRecords(itemRes);
  }, []);

  // Inventory
  const [filteredInventories, setFilteredInventories] = useState<InventoryResult[]>([]);
  const [inventoriesPagingController, setInventoriesPagingController] = useState(defaultPagingController)
  const [inventoriesTotalCount, setInventoriesTotalCount] = useState(0)
  const [selectedInventory, setSelectedInventory] = useState<InventoryResult | null>(null)
  const [detailTab, setDetailTab] = useState(0)
  const tabsRef = useRef<HTMLDivElement>(null)

  // Inventory Lot Line
  const [filteredInventoryLotLines, setFilteredInventoryLotLines] = useState<InventoryLotLineResult[]>([]);
  const [inventoryLotLinesPagingController, setInventoryLotLinesPagingController] = useState(defaultPagingController)
  const [inventoryLotLinesTotalCount, setInventoryLotLinesTotalCount] = useState(0)

  const applyItemsAsSyntheticInventories = useCallback(
    (items: ItemLookupRow[]) => {
      if (!items.length) return false;
      const synthetics = items.map(buildSyntheticInventory);
      setFilteredInventories(synthetics);
      setInventoriesTotalCount(synthetics.length);
      setSelectedInventory(synthetics[0]);
      setFilteredInventoryLotLines([]);
      setInventoryLotLinesPagingController(() => defaultPagingController);
      return true;
    },
    [buildSyntheticInventory],
  );

  // Scan-mode UI (hardware QR scanner via QrCodeScannerProvider)
  const qrScanner = useQrCodeScannerContext();
  const [scanUiMode, setScanUiMode] = useState<'idle' | 'scanning'>('idle');
  const [scanHoverCancel, setScanHoverCancel] = useState(false);

  // Resolved lot no for filtering
  const [lotNoFilter, setLotNoFilter] = useState('');
  const [scannedItemId, setScannedItemId] = useState<number | null>(null);

  const defaultInputs = useMemo(
    () => ({
      itemId: '',
      itemCode: '',
      itemName: '',
      itemType: '',
      onHandQty: '',
      onHoldQty: '',
      unavailableQty: '',
      availableQty: '',
      currencyName: '',
      status: '',
      baseUom: '',
      uomShortDesc: '',
      latestMarketUnitPrice: '',
      latestMupUpdatedDate: '',
    }),
    [],
  );
  const [inputs, setInputs] = useState<Record<SearchParamNames, string>>(defaultInputs);

  const searchCriteria: Criterion<SearchParamNames>[] = useMemo(
    () => [
      { label: t('Code'), paramName: 'itemCode', type: 'text' },
      { label: t('Name'), paramName: 'itemName', type: 'text' },
      {
        label: t('Type'),
        paramName: 'itemType',
        type: 'select-labelled',
        options: uniq(inventories.map((i) => i.itemType)).map((type) => ({
          value: type,
          label: t(type),
        })),
      },
      // {
      //   label: t("Status"),
      //   paramName: "status",
      //   type: "select",
      //   options: uniq(inventories.map((i) => i.status)),
      // },
    ],
    [t, inventories],
  );

  // Inventory
  const refetchInventoryData = useCallback(
    async (
      query: Record<SearchParamNames, string>,
      actionType: 'reset' | 'search' | 'paging' | 'init',
      pagingController: typeof defaultPagingController,
      lotNo: string,
    ) => {
      //console.log('%c Action Type 1.', 'color:red', actionType);
      // Avoid loading data again
      if (actionType === 'paging' && pagingController === defaultPagingController) {
        return;
      }
     // console.log('%c Action Type 2.', 'color:blue', actionType);

      const params: SearchInventory = {
        code: query?.itemCode ?? '',
        name: query?.itemName ?? '',
        type: query?.itemType.toLowerCase() === 'all' ? '' : query?.itemType ?? '',
        lotNo: lotNo?.trim() ? lotNo.trim() : undefined,
        pageNum: pagingController.pageNum - 1,
        pageSize: pagingController.pageSize,
      };

      const response = await fetchInventoriesLatest(params);

      if (response) {
        setInventoriesTotalCount(response.total);
        switch (actionType) {
          case 'init':
          case 'reset':
          case 'search':
            setFilteredInventories(() => response.records);
            break;
          case 'paging':
            setFilteredInventories((fi) =>
              uniqBy([...fi, ...response.records], 'itemId'),
            );
        }
      }

      return response;
    },
    [],
  );

  useEffect(() => {
    refetchInventoryData(defaultInputs, 'init', defaultPagingController, '');
  }, [defaultInputs, refetchInventoryData]);

  useEffect(() => {
    // if (!isEqual(inventoriesPagingController, defaultPagingController)) {
      refetchInventoryData(inputs, 'paging', inventoriesPagingController, lotNoFilter)
    // }
  }, [inventoriesPagingController, inputs, lotNoFilter, refetchInventoryData])

  // Inventory Lot Line
  const refetchInventoryLotLineData = useCallback(
    async (
      itemId: number | null,
      actionType: 'reset' | 'search' | 'paging',
      pagingController: typeof defaultPagingController,
    ) => {
      if (!itemId) {
        setSelectedInventory(null);
        setInventoryLotLinesTotalCount(0);
        setFilteredInventoryLotLines([]);
        return;
      }

      // Avoid loading data again
      if (actionType === 'paging' && pagingController === defaultPagingController) {
        return;
      }

      const params: SearchInventoryLotLine = {
        itemId,
        pageNum: pagingController.pageNum - 1,
        pageSize: pagingController.pageSize,
      };

      const response = await fetchInventoryLotLines(params);
      if (response) {
        setInventoryLotLinesTotalCount(response.total);
        switch (actionType) {
          case 'reset':
          case 'search':
            setFilteredInventoryLotLines(() => response.records);
            break;
          case 'paging':
            setFilteredInventoryLotLines((fi) => uniqBy([...fi, ...response.records], 'id'));
        }
      }
    },
    [],
  );

  useEffect(() => {
    // if (!isEqual(inventoryLotLinesPagingController, defaultPagingController)) {
      refetchInventoryLotLineData(selectedInventory?.itemId ?? null, 'paging', inventoryLotLinesPagingController)
    // }
  }, [inventoryLotLinesPagingController])

  // Reset
  const onReset = useCallback(() => {
    refetchInventoryData(defaultInputs, 'reset', defaultPagingController, '');
    refetchInventoryLotLineData(null, 'reset', defaultPagingController);
    // setFilteredInventories(inventories);

    setLotNoFilter('');
    setScannedItemId(null);
    setScanUiMode('idle');
    setScanHoverCancel(false);
    qrScanner.stopScan();
    qrScanner.resetScan();
    setInputs(() => defaultInputs)
    setInventoriesPagingController(() => defaultPagingController)
    setInventoryLotLinesPagingController(() => defaultPagingController)
  }, [defaultInputs, qrScanner, refetchInventoryData, refetchInventoryLotLineData]);

  // Click Row
  const onInventoryRowClick = useCallback(
    (item: InventoryResult) => {
      refetchInventoryLotLineData(item.itemId, 'search', defaultPagingController);
      setSelectedInventory(item);
      setInventoryLotLinesPagingController(() => defaultPagingController);
    },
    [refetchInventoryLotLineData],
  );

  useEffect(() => {
    if (selectedInventory?.itemId == null) return;
    const row = document.querySelector('[data-inventory-selected="true"]');
    const container = row?.closest('.MuiTableContainer-root');
    if (row instanceof HTMLElement && container instanceof HTMLElement) {
      const rowRect = row.getBoundingClientRect();
      const box = container.getBoundingClientRect();
      if (rowRect.top < box.top) {
        container.scrollTop -= box.top - rowRect.top;
      } else if (rowRect.bottom > box.bottom) {
        container.scrollTop += rowRect.bottom - box.bottom;
      }
    }
    const tabs = tabsRef.current;
    if (tabs) {
      const rect = tabs.getBoundingClientRect();
      if (rect.bottom > window.innerHeight - 8) {
        tabs.scrollIntoView({ block: 'end', behavior: 'smooth' });
      }
    }
  }, [selectedInventory?.itemId]);

  // On Search
  const onSearch = useCallback(
    async (query: Record<SearchParamNames, string>) => {
      if (searchInFlightRef.current) return;
      searchInFlightRef.current = true;
      try {
        setLotNoFilter('');
        setScannedItemId(null);
        setScanUiMode('idle');
        setScanHoverCancel(false);
        qrScanner.stopScan();
        qrScanner.resetScan();
        const invRes = await refetchInventoryData(query, 'search', defaultPagingController, '');
        await refetchInventoryLotLineData(null, 'search', defaultPagingController);

        setInputs(() => query);
        setInventoriesPagingController(() => defaultPagingController);
        setInventoryLotLinesPagingController(() => defaultPagingController);

        // No inventory rows: look up item master so 0-qty rows can be selected for stock adjustment.
        if (canStockAdjust && invRes?.records?.length === 0) {
          try {
            const items = await lookupItemsByCodeOrName(query.itemCode, query.itemName);
            const typeFilter = query.itemType?.trim();
            let filtered =
              typeFilter && typeFilter.toLowerCase() !== 'all'
                ? items.filter((it) => (it.type ?? '').toLowerCase() === typeFilter.toLowerCase())
                : items;
            const exactCode = query.itemCode?.trim().toLowerCase();
            if (exactCode) {
              filtered = [...filtered].sort((a, b) => {
                const aExact = a.code?.toLowerCase() === exactCode ? 0 : 1;
                const bExact = b.code?.toLowerCase() === exactCode ? 0 : 1;
                return aExact - bExact;
              });
            }
            applyItemsAsSyntheticInventories(filtered);
          } catch (e) {
            console.error('Failed to build synthetic inventory:', e);
          }
        }
      } finally {
        searchInFlightRef.current = false;
      }
    },
    [
      qrScanner,
      refetchInventoryData,
      refetchInventoryLotLineData,
      lookupItemsByCodeOrName,
      applyItemsAsSyntheticInventories,
      canStockAdjust,
    ],
  );

  const startLotScan = useCallback(() => {
    setScanHoverCancel(false);
    setScanUiMode('scanning');
    qrScanner.resetScan();
    qrScanner.startScan();
  }, [qrScanner]);

  const cancelLotScan = useCallback(() => {
    qrScanner.stopScan();
    qrScanner.resetScan();
    setScanUiMode('idle');
    setScanHoverCancel(false);
  }, [qrScanner]);

  useEffect(() => {
    if (scanUiMode !== 'scanning') return;

    const itemId = qrScanner.result?.itemId;
    const stockInLineId = qrScanner.result?.stockInLineId;
    if (!itemId || !stockInLineId) return;

    (async () => {
      try {
        const res = await analyzeQrCode({
          itemId: Number(itemId),
          stockInLineId: Number(stockInLineId),
        });

        const resolvedLotNo = res?.scanned?.lotNo?.trim?.() ? res.scanned.lotNo.trim() : '';
        if (!resolvedLotNo) return;

        setLotNoFilter(resolvedLotNo);
        setScannedItemId(res?.itemId ?? Number(itemId));

        const invRes = await refetchInventoryData(inputs, 'search', defaultPagingController, resolvedLotNo);
        const records = invRes?.records ?? [];
        const target = records.find((r) => r.itemId === (res?.itemId ?? Number(itemId))) ?? null;

        if (target) {
          onInventoryRowClick(target);
        } else {
          refetchInventoryLotLineData(null, 'search', defaultPagingController);
          if (canStockAdjust) {
            const items = await lookupItemsByCodeOrName(res?.itemCode);
            if (!applyItemsAsSyntheticInventories(items)) {
              setSelectedInventory(null);
            }
          } else {
            setSelectedInventory(null);
          }
        }

        setInventoriesPagingController(() => defaultPagingController);
        setInventoryLotLinesPagingController(() => defaultPagingController);
      } catch (e) {
        console.error('Failed to analyze QR code:', e);
      } finally {
        // Always go back to initial state after a scan attempt
        cancelLotScan();
      }
    })();
  }, [
    cancelLotScan,
    inputs,
    onInventoryRowClick,
    qrScanner.result,
    refetchInventoryData,
    refetchInventoryLotLineData,
    lookupItemsByCodeOrName,
    applyItemsAsSyntheticInventories,
    canStockAdjust,
    scanUiMode,
  ]);

  return (
    <>
      <SearchBox
        criteria={searchCriteria}
        onSearch={(query) => {
          onSearch(query);
        }}
        onReset={onReset}
        extraActions={
          <Box sx={{ display: 'flex', gap: 1, alignItems: 'center', flexWrap: 'wrap' }}>
            {scanUiMode === 'idle' ? (
              <Button variant="contained" onClick={startLotScan}>
                {t('Search lot by QR code')}
              </Button>
            ) : (
              <>
                <Button variant="contained" disabled sx={{ bgcolor: 'grey.400', color: 'grey.800' }}>
                  {t('Please scan...')}
                </Button>
                <Button variant="contained" color="error" onClick={cancelLotScan}>
                  {t('Stop QR Scan')}
                </Button>
              </>
            )}
          </Box>
        }
      />
      <InventoryTable
        inventories={filteredInventories}
        pagingController={inventoriesPagingController}
        setPagingController={setInventoriesPagingController}
        totalCount={inventoriesTotalCount}
        onRowClick={onInventoryRowClick}
        selectedItemId={selectedInventory?.itemId}
        maxHeight={440}
      />
      <Box ref={tabsRef} sx={{ mt: 1 }}>
      <Tabs
        value={detailTab}
        onChange={(_, value) => setDetailTab(value)}
        sx={{ bgcolor: 'background.paper' }}
      >
        <Tab label={t('Lots')} />
        <Tab label={t('Stock Movements')} />
        <Tab label={t('Unit Conversion')} />
      </Tabs>
      </Box>
      {selectedInventory && <InventoryQtyStory inventory={selectedInventory} />}
      {detailTab === 0 ? (
      <InventoryLotLineTable
        inventoryLotLines={filteredInventoryLotLines}
        pagingController={inventoryLotLinesPagingController}
        setPagingController={setInventoryLotLinesPagingController}
        totalCount={inventoryLotLinesTotalCount}
        inventory={selectedInventory}
        filterLotNo={lotNoFilter}
        printerCombo={printerCombo ?? []}
        onStockTransferSuccess={() =>
          refetchInventoryLotLineData(
            selectedInventory?.itemId ?? null,
            'search',
            inventoryLotLinesPagingController,
          )
        }
        onStockAdjustmentSuccess={async () => {
          const itemId = selectedInventory?.itemId ?? null;

          // Refresh both blocks:
          // - middle: InventoryTable (inventories list)
          // - bottom: InventoryLotLineTable (lot lines for selected item)
          const invRes = await refetchInventoryData(
            inputs,
            'search',
            inventoriesPagingController,
            lotNoFilter,
          );

          await refetchInventoryLotLineData(
            itemId,
            'search',
            inventoryLotLinesPagingController,
          );

          // If inventory becomes available again after OPEN/ADJ, sync selected row.
          if (itemId != null && invRes?.records?.length) {
            const target = invRes.records.find((r) => r.itemId === itemId);
            if (target) setSelectedInventory(target);
          }
        }}
      />
      ) : detailTab === 1 ? (
        <InventoryItemLedger
          key={selectedInventory?.itemId ?? 'none'}
          inventory={selectedInventory}
        />
      ) : (
        <InventoryItemUom
          key={selectedInventory?.itemId ?? 'none'}
          inventory={selectedInventory}
        />
      )}
    </>
  );
};

export default InventorySearch;