"use client";

import React, { useCallback, useEffect, useMemo, useState } from "react";
import {
  Box,
  Button,
  Dialog,
  DialogActions,
  DialogContent,
  DialogTitle,
  Grid,
  Stack,
  Table,
  TableBody,
  TableCell,
  TableContainer,
  TableHead,
  TableRow,
  TextField,
  Typography,
  IconButton,
  CircularProgress,
} from "@mui/material";
import { useTranslation } from "react-i18next";
import { Add, Delete, Edit } from "@mui/icons-material";
import SearchBox, { Criterion } from "../SearchBox/SearchBox";
import SearchResults, { Column } from "../SearchResults/SearchResults";
import {
  saveItemQcCategoryMapping,
  deleteItemQcCategoryMapping,
  getItemQcCategoryMappings,
  fetchQcCategoriesForAll,
  fetchItemsForAll,
  getItemByCode,
  getCategoryType,
  updateCategoryType,
} from "@/app/api/settings/qcItemAll/actions";
import {
  QcCategoryResult,
  ItemsResult,
} from "@/app/api/settings/qcItemAll";
import { ItemQcCategoryMappingInfo } from "@/app/api/settings/qcItemAll";
import {
  deleteDialog,
  errorDialogWithContent,
  submitDialog,
  successDialog,
} from "../Swal/CustomAlerts";

type SearchQuery = Partial<Omit<QcCategoryResult, "id">>;
type SearchParamNames = keyof SearchQuery;

const Tab0ItemQcCategoryMapping: React.FC = () => {
  const { t } = useTranslation("qcItemAll");
  const [qcCategories, setQcCategories] = useState<QcCategoryResult[]>([]);
  const [filteredQcCategories, setFilteredQcCategories] = useState<QcCategoryResult[]>([]);
  const [selectedCategory, setSelectedCategory] = useState<QcCategoryResult | null>(null);
  const [mappings, setMappings] = useState<ItemQcCategoryMappingInfo[]>([]);
  const [openDialog, setOpenDialog] = useState(false);
  const [openAddDialog, setOpenAddDialog] = useState(false);
  const [itemCode, setItemCode] = useState<string>("");
  const [validatedItem, setValidatedItem] = useState<ItemsResult | null>(null);
  const [itemCodeError, setItemCodeError] = useState<string>("");
  const [validatingItemCode, setValidatingItemCode] = useState<boolean>(false);
  const [selectedType, setSelectedType] = useState<string>("IQC");
  const [loading, setLoading] = useState(true);
  const [categoryType, setCategoryType] = useState<string>("IQC");
  const [savingCategoryType, setSavingCategoryType] = useState(false);
  useEffect(() => {
    const loadData = async () => {
      setLoading(true);
      try {
        // Only load categories list (same as Tab 2) - fast!
        const categories = await fetchQcCategoriesForAll();
        setQcCategories(categories || []);
        setFilteredQcCategories(categories || []);
      } catch (error) {
        console.error("Tab0: Error loading data:", error);
        setQcCategories([]);
        setFilteredQcCategories([]);
        if (error instanceof Error) {
          errorDialogWithContent(t("Error"), error.message, t);
        }
      } finally {
        setLoading(false);
      }
    };
    loadData();
  }, []);

  const handleViewMappings = useCallback(async (category: QcCategoryResult) => {
    setSelectedCategory(category);
    const [mappingData, typeFromApi] = await Promise.all([
      getItemQcCategoryMappings(category.id),
      getCategoryType(category.id),
    ]);
    setMappings(mappingData);
    setCategoryType(typeFromApi ?? "IQC");  // 方案 A: no mappings -> default IQC
    setOpenDialog(true);
  }, []);

  const handleAddMapping = useCallback(() => {
    if (!selectedCategory) return;
    setItemCode("");
    setValidatedItem(null);
    setItemCodeError("");
    setSelectedType(categoryType);
    setOpenAddDialog(true);
  }, [selectedCategory, categoryType]);
  
  const handleItemCodeChange = useCallback(async (code: string) => {
    setItemCode(code);
    setValidatedItem(null);
    setItemCodeError("");
    
    if (!code || code.trim() === "") {
      return;
    }
    if (code.trim().length !== 6) {
      return;
    }
    setValidatingItemCode(true);
    try {
      const item = await getItemByCode(code.trim());
      if (item) {
        setValidatedItem(item);
        setItemCodeError("");
      } else {
        setValidatedItem(null);
        setItemCodeError(t("Item code not found"));
      }
    } catch (error) {
      setValidatedItem(null);
      setItemCodeError(t("Error validating item code"));
    } finally {
      setValidatingItemCode(false);
    }
  }, [t]);

  const handleSaveMapping = useCallback(async () => {
    if (!selectedCategory || !validatedItem) return;

    await submitDialog(async () => {
      try {
        await saveItemQcCategoryMapping(
          validatedItem.id as number,
          selectedCategory.id,
          selectedType
          //categoryType
        );
        // Close add dialog first
        setOpenAddDialog(false);
        setItemCode("");
        setValidatedItem(null);
        setItemCodeError("");
        // Reload mappings to update the view
        const mappingData = await getItemQcCategoryMappings(selectedCategory.id);
        setMappings(mappingData);
        // Show success message after closing dialogs
        await successDialog(t("Submit Success"), t);
        // Keep the view dialog open to show updated data
      } catch (error: unknown) {
        let message: string;
      
        if (error && typeof error === "object" && "message" in error) {
          message = String((error as { message?: string }).message);
        } else {
          message = String(error);
        }
      
        // 嘗試從 message 裡解析出後端 FailureRes.error
        try {
          const jsonStart = message.indexOf("{");
          if (jsonStart >= 0) {
            const jsonPart = message.slice(jsonStart);
            const parsed = JSON.parse(jsonPart);
            if (parsed.error) {
              message = parsed.error;
            }
          }
        } catch {
          // 解析失敗就維持原本的 message
        }
        let displayMessage = message; 
        if (displayMessage.includes("already has type") && displayMessage.includes("linked to QcCategory")) {
          const match = displayMessage.match(/type "([^"]+)" linked to QcCategory[:\s]+(.+?)(?:\.|One item)/);
          const type = match?.[1] ?? "";
          const categoryName = match?.[2]?.trim() ?? "";
          displayMessage = t("Item already has type \"{{type}}\" in QcCategory \"{{category}}\". One item can only have each type in one QcCategory.", {
            type,
            category: categoryName,
          });
        }
        
        errorDialogWithContent(t("Submit Error"), displayMessage || t("Submit Error"), t);
      }
    }, t);
  }, [selectedCategory, validatedItem, selectedType, t]);

  const handleDeleteMapping = useCallback(
    async (mappingId: number) => {
      if (!selectedCategory) return;

      deleteDialog(async () => {
        try {
          await deleteItemQcCategoryMapping(mappingId);
          await successDialog(t("Delete Success"), t);
        // Reload mappings
        const mappingData = await getItemQcCategoryMappings(selectedCategory.id);
        setMappings(mappingData);
        // No need to reload categories list - it doesn't change
        } catch (error) {
          errorDialogWithContent(t("Delete Error"), String(error), t);
        }
      }, t);
    },
    [selectedCategory, t]
  );

  const typeOptions = ["IQC", "IPQC", "EPQC"];
  function formatTypeDisplay(value: unknown): string {
    if (value == null) return "null";
    if (typeof value === "string") return value;
    if (typeof value === "object" && value !== null && "type" in value) {
      const v = (value as { type?: unknown }).type;
      if (typeof v === "string") return v;
      if (v != null && typeof v === "object") return "null"; // 避免 [object Object]
      return "null";
    }
    return "null";
  }
  const searchCriteria: Criterion<SearchParamNames>[] = useMemo(
    () => [
      { label: t("Code"), paramName: "code", type: "text" },
      { label: t("Name"), paramName: "name", type: "text" },
    ],
    [t]
  );

  const onReset = useCallback(() => {
    setFilteredQcCategories(qcCategories);
  }, [qcCategories]);

  const columnWidthSx = (width = "10%") => {
    return { width: width, whiteSpace: "nowrap" };
  };

  const columns = useMemo<Column<QcCategoryResult>[]>(
    () => [
      { name: "code", label: t("Qc Category Code"), sx: columnWidthSx("20%") },
      { name: "name", label: t("Qc Category Name"), sx: columnWidthSx("40%") },
      {
        name: "type",
        label: t("Type"),
        sx: columnWidthSx("10%"),
        renderCell: (row) => {
          const t = row.type;
          if (t == null) return " ";               // 原来是 "null"
          if (typeof t === "string") return t;
          if (typeof t === "object" && t !== null && "type" in t) {
            const v = (t as { type?: unknown }).type;
            return typeof v === "string" ? v : " "; // 原来是 "null"
          }
          return " ";                               // 原来是 "null"
        },
      },
      {
        name: "id",
        label: t("Actions"),
        onClick: (category) => handleViewMappings(category),
        buttonIcon: <Edit />,
        buttonIcons: {} as any,
        sx: columnWidthSx("10%"),
      },
    ],
    [t, handleViewMappings]
  );

  if (loading) {
    return (
      <Box sx={{ display: "flex", justifyContent: "center", alignItems: "center", minHeight: "200px" }}>
        <CircularProgress />
      </Box>
    );
  }

  return (
    <Box>
      <SearchBox
        criteria={searchCriteria}
        onSearch={(query) => {
          setFilteredQcCategories(
            qcCategories.filter(
              (qc) =>
                (!query.code || qc.code.toLowerCase().includes(query.code.toLowerCase())) &&
                (!query.name || qc.name.toLowerCase().includes(query.name.toLowerCase()))
            )
          );
        }}
        onReset={onReset}
      />
      <SearchResults<QcCategoryResult>
        items={filteredQcCategories}
        columns={columns}
      />

      {/* View Mappings Dialog */}
      <Dialog open={openDialog} onClose={() => setOpenDialog(false)} maxWidth="md" fullWidth sx={{ zIndex: 1000 }}>
        <DialogTitle>
          {t("Mapping Details")} - {selectedCategory?.name}
        </DialogTitle>
        <DialogContent>
        <Stack direction="row" alignItems="center" spacing={2} sx={{ mb: 1 }}>
          </Stack>
        <Stack
          direction="row"
          alignItems="center"
          spacing={2}
          sx={{ mb: 1, minHeight: 40 }}
        >
          <Typography
            variant="body2"
            sx={{ display: "flex", alignItems: "center", minHeight: 40 }}
          >
            {t("Category Type")}
          </Typography>
          <TextField
            select
            size="small"
            sx={{ minWidth: 120 }}
            value={categoryType}
            onChange={(e) => setCategoryType(e.target.value)}
            SelectProps={{ native: true }}
          >
            {typeOptions.map((opt) => (
              <option key={opt} value={opt}>{opt}</option>
            ))}
          </TextField>
          <Button
            variant="outlined"
            size="small"
            disabled={savingCategoryType}
            onClick={async () => {
              if (!selectedCategory) return;
              setSavingCategoryType(true);
              try {
                await updateCategoryType(selectedCategory.id, categoryType);
                setQcCategories(prev =>
                  prev.map(cat =>
                    cat.id === selectedCategory.id ? { ...cat, type: categoryType } : cat
                  )
                );
                setFilteredQcCategories(prev =>
                  prev.map(cat =>
                    cat.id === selectedCategory.id ? { ...cat, type: categoryType } : cat
                  )
                );
                // 2) 同步 selectedCategory，讓 Dialog 標題旁邊的資料也一致
                setSelectedCategory(prev =>
                  prev && prev.id === selectedCategory.id ? { ...prev, type: categoryType } : prev
                );
                await successDialog(t("Submit Success"), t);
                const mappingData = await getItemQcCategoryMappings(selectedCategory.id);
                setMappings(mappingData);
              } catch (e) {
                errorDialogWithContent(t("Submit Error"), String(e), t);
              } finally {
                setSavingCategoryType(false);
              }
            }}
          >
            {t("Save")}
          </Button>
          <Box sx={{ display: "flex", justifyContent: "flex-end" }}>
              <Button
                variant="contained"
                startIcon={<Add />}
                onClick={handleAddMapping}
              >
                {t("Add Mapping")}
              </Button>
            </Box>
        </Stack>
          <Stack spacing={2} sx={{ mt: 1 }}>
        
            <TableContainer>
              <Table>
                <TableHead>
                  <TableRow>
                    <TableCell>{t("Item Code")}</TableCell>
                    <TableCell>{t("Item Name")}</TableCell>
                    <TableCell>{t("Type")}</TableCell>
                    <TableCell>{t("Actions")}</TableCell>
                  </TableRow>
                </TableHead>
                <TableBody>
                  {mappings.length === 0 ? (
                    <TableRow>
                      <TableCell colSpan={4} align="center">
                        {t("No mappings found")}
                      </TableCell>
                    </TableRow>
                  ) : (
                    mappings.map((mapping) => (
                      <TableRow key={mapping.id}>
                        <TableCell>{mapping.itemCode}</TableCell>
                        <TableCell>{mapping.itemName}</TableCell>
                        <TableCell>
                          {formatTypeDisplay(mapping.type)}
                        </TableCell>
                        <TableCell>
                          <IconButton
                            color="error"
                            size="small"
                            onClick={() => handleDeleteMapping(mapping.id)}
                          >
                            <Delete />
                          </IconButton>
                        </TableCell>
                      </TableRow>
                    ))
                  )}
                </TableBody>
              </Table>
            </TableContainer>
          </Stack>
        </DialogContent>
        <DialogActions>
          <Button onClick={() => setOpenDialog(false)}>{t("Cancel")}</Button>
        </DialogActions>
      </Dialog>

      {/* Add Mapping Dialog */}
      <Dialog open={openAddDialog} onClose={() => setOpenAddDialog(false)} maxWidth="sm" fullWidth sx={{ zIndex: 1000 }}>
        <DialogTitle>{t("Add Mapping")}</DialogTitle>
        <DialogContent>
          <Stack spacing={2} sx={{ mt: 2 }}>
            <TextField
              label={t("Item Code")}
              value={itemCode}
              onChange={(e) => handleItemCodeChange(e.target.value)}
              error={!!itemCodeError}
              helperText={itemCodeError || (validatedItem ? `${validatedItem.code} - ${validatedItem.name}` : t("Enter item code to validate"))}
              fullWidth
              disabled={validatingItemCode}
              InputProps={{
                endAdornment: validatingItemCode ? <CircularProgress size={20} /> : null,
              }}
            />
            <TextField
              select
              label={t("Select Type")}
              value={selectedType}
              onChange={(e) => setSelectedType(e.target.value)}
              SelectProps={{
                native: true,
              }}
              fullWidth
            >
              {typeOptions.map((type) => (
                <option key={type} value={type}>
                  {type}
                </option>
              ))}
            </TextField>
          </Stack>
        </DialogContent>
        <DialogActions>
          <Button onClick={() => setOpenAddDialog(false)}>{t("Cancel")}</Button>
          <Button
            variant="contained"
            onClick={handleSaveMapping}
            disabled={!validatedItem}
          >
            {t("Save")}
          </Button>
        </DialogActions>
      </Dialog>
    </Box>
  );
};

export default Tab0ItemQcCategoryMapping;