import { useSession } from "next-auth/react";
import Box from "@mui/material/Box";
import React from "react";
import List from "@mui/material/List";
import ListItemButton from "@mui/material/ListItemButton";
import ListItemText from "@mui/material/ListItemText";
import ListItemIcon from "@mui/material/ListItemIcon";
import Dashboard from "@mui/icons-material/Dashboard";
import Storefront from "@mui/icons-material/Storefront";
import LocalShipping from "@mui/icons-material/LocalShipping";
import Assignment from "@mui/icons-material/Assignment";
import Inventory from "@mui/icons-material/Inventory";
import AssignmentTurnedIn from "@mui/icons-material/AssignmentTurnedIn";
import ReportProblem from "@mui/icons-material/ReportProblem";
import QrCodeIcon from "@mui/icons-material/QrCode";
import ViewModule from "@mui/icons-material/ViewModule";
import Description from "@mui/icons-material/Description";
import CalendarMonth from "@mui/icons-material/CalendarMonth";
import Factory from "@mui/icons-material/Factory";
import PostAdd from "@mui/icons-material/PostAdd";
import Kitchen from "@mui/icons-material/Kitchen";
import Inventory2 from "@mui/icons-material/Inventory2";
import Print from "@mui/icons-material/Print";
import Assessment from "@mui/icons-material/Assessment";
import ShowChart from "@mui/icons-material/ShowChart";
import Settings from "@mui/icons-material/Settings";
import Person from "@mui/icons-material/Person";
import Group from "@mui/icons-material/Group";
import Category from "@mui/icons-material/Category";
import TrendingUp from "@mui/icons-material/TrendingUp";
import Build from "@mui/icons-material/Build";
import Warehouse from "@mui/icons-material/Warehouse";
import VerifiedUser from "@mui/icons-material/VerifiedUser";
import Label from "@mui/icons-material/Label";
import Checklist from "@mui/icons-material/Checklist";
import Science from "@mui/icons-material/Science";
import UploadFile from "@mui/icons-material/UploadFile";
import { useTranslation } from "react-i18next";
import { usePathname } from "next/navigation";
import Link from "next/link";
import { NAVIGATION_CONTENT_WIDTH } from "@/config/uiConfig";
import Logo from "../Logo";
import { AUTH } from "../../authorities";

interface NavigationItem {
  icon: React.ReactNode;
  label: string;
  path: string;
  children?: NavigationItem[];
  isHidden?: boolean | undefined;
  requiredAbility?: string | string[];
}

const NavigationContent: React.FC = () => {
  const { data: session, status } = useSession();
  const abilities = session?.user?.abilities ?? [];

  // Helper: check if user has required permission
  const hasAbility = (required?: string | string[]): boolean => {
    if (!required) return true; // no requirement → always show
    if (Array.isArray(required)) {
      return required.some(ability => abilities.includes(ability));
    }
    return abilities.includes(required);
  };

  const navigationItems: NavigationItem[] = [
    {
      icon: <Dashboard />,
      label: "Dashboard",
      path: "/dashboard",
    },
    {
      icon: <Storefront />,
      label: "Store Management",
      path: "",
      requiredAbility: [AUTH.PURCHASE, AUTH.STOCK, AUTH.STOCK_TAKE, AUTH.STOCK_FG, AUTH.STOCK_IN_BIND, AUTH.ADMIN],
      children: [
        {
          icon: <LocalShipping />,
          label: "Purchase Order",
          requiredAbility: [AUTH.PURCHASE, AUTH.ADMIN],
          path: "/po",
        },
        {
          icon: <Assignment />,
          label: "Pick Order",
          requiredAbility: [AUTH.STOCK, AUTH.ADMIN],
          path: "/pickOrder",
        },
        {
          icon: <Inventory />,
          label: "View item In-out And inventory Ledger",
          requiredAbility: [AUTH.STOCK, AUTH.ADMIN],
          path: "/inventory",
        },
        {
          icon: <AssignmentTurnedIn />,
          label: "Stock Take Management",
          requiredAbility: [AUTH.STOCK, AUTH.STOCK_TAKE, AUTH.ADMIN],
          path: "/stocktakemanagement",
        },
        {
          icon: <ReportProblem />,
          label: "Stock Issue",
          requiredAbility: [AUTH.STOCK, AUTH.STOCK_TAKE, AUTH.ADMIN],
          path: "/stockIssue",
        },
        {
          icon: <QrCodeIcon />,
          label: "Put Away Scan",
          requiredAbility: [AUTH.STOCK, AUTH.STOCK_TAKE, AUTH.STOCK_IN_BIND, AUTH.ADMIN],
          path: "/putAway",
        },
        {
          icon: <ViewModule />,
          label: "Finished Good Order",
          requiredAbility: [AUTH.STOCK_FG, AUTH.ADMIN],
          path: "/finishedGood",
        },
        {
          icon: <Description />,
          label: "Stock Record",
          requiredAbility: [AUTH.STOCK, AUTH.STOCK_TAKE, AUTH.STOCK_IN_BIND, AUTH.STOCK_FG, AUTH.ADMIN],
          path: "/stockRecord",
        },
      ],
    },
    {
      icon: <LocalShipping />,
      label: "Delivery Order",
      path: "/do",
      requiredAbility: [AUTH.STOCK_FG, AUTH.ADMIN],
    },
    {
      icon: <CalendarMonth />,
      label: "Scheduling",
      path: "/ps",
      requiredAbility: [AUTH.FORECAST, AUTH.ADMIN],
      isHidden: false,
    },
    {
      icon: <Factory />,
      label: "Management Job Order",
      path: "",
      requiredAbility: [AUTH.JOB_CREATE, AUTH.JOB_PICK, AUTH.JOB_PROD, AUTH.ADMIN],
      children: [
        {
          icon: <PostAdd />,
          label: "Search Job Order/ Create Job Order",
          requiredAbility: [AUTH.JOB_CREATE, AUTH.ADMIN],
          path: "/jo",
        },
        {
          icon: <Inventory />,
          label: "Job Order Pickexcution",
          requiredAbility: [AUTH.JOB_PICK, AUTH.JOB_MAT, AUTH.ADMIN],
          path: "/jodetail",
        },
        {
          icon: <Kitchen />,
          label: "Job Order Production Process",
          requiredAbility: [AUTH.JOB_PROD, AUTH.ADMIN],
          path: "/productionProcess",
        },
        {
          icon: <Inventory2 />,
          label: "Bag Usage",
          requiredAbility: [AUTH.JOB_PROD, AUTH.ADMIN],
          path: "/bag",
        },
      ],
    },
    {
      icon: <Print />,
      label: "打袋機",
      path: "/bagPrint",
      requiredAbility: [AUTH.JOB_PROD, AUTH.ADMIN],
      isHidden: false,
    },
    {
      icon: <Assessment />,
      label: "報告管理",
      path: "/report",
      requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
      isHidden: false,
    },
    {
      icon: <ShowChart />,
      label: "圖表報告",
      path: "",
      requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
      isHidden: false,
      children: [
        {
          icon: <Warehouse />,
          label: "庫存與倉儲",
          path: "/chart/warehouse",
          requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
        },
        {
          icon: <Storefront />,
          label: "採購",
          path: "/chart/purchase",
          requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
        },
        {
          icon: <LocalShipping />,
          label: "發貨與配送",
          path: "/chart/delivery",
          requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
        },
        {
          icon: <Assignment />,
          label: "工單",
          path: "/chart/joborder",
          requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
        },
        {
          icon: <TrendingUp />,
          label: "預測與計劃",
          path: "/chart/forecast",
          requiredAbility: [AUTH.TESTING, AUTH.ADMIN],
        },
      ],
    },
    {
      icon: <Settings />,
      label: "Settings",
      path: "",
      requiredAbility: [AUTH.VIEW_USER, AUTH.ADMIN],
      children: [
        {
          icon: <Person />,
          label: "User",
          path: "/settings/user",
          requiredAbility: [AUTH.VIEW_USER, AUTH.ADMIN],
        },
        //{
        //  icon: <Group />,
        //  label: "User Group",
        //  path: "/settings/user",
        //  requiredAbility: [AUTH.VIEW_GROUP, AUTH.ADMIN],
        //},
        {
          icon: <Category />,
          label: "Items",
          path: "/settings/items",
        },
        {
          icon: <Build />,
          label: "Equipment",
          path: "/settings/equipment",
        },
        {
          icon: <Assessment />,
          label: "Price Inquiry",
          path: "/settings/itemPrice",
        },
        {
          icon: <Warehouse />,
          label: "Warehouse",
          path: "/settings/warehouse",
        },
        {
          icon: <Print />,
          label: "Printer",
          path: "/settings/printer",
        },
        {
          icon: <VerifiedUser />,
          label: "QC Check Item",
          path: "/settings/qcItem",
        },
        {
          icon: <Label />,
          label: "QC Category",
          path: "/settings/qcCategory",
        },
        {
          icon: <Checklist />,
          label: "QC Item All",
          path: "/settings/qcItemAll",
        },
        {
          icon: <Storefront />,
          label: "ShopAndTruck",
          path: "/settings/shop",
        },
        {
          icon: <TrendingUp />,
          label: "Demand Forecast Setting",
          path: "/settings/rss",
        },
        //{
        //  icon: <Person />,
        //  label: "Customer",
        //  path: "/settings/user",
        //},
        {
          icon: <ViewModule />,
          label: "BOM Weighting Score List",
          path: "/settings/bomWeighting",
        },
        {
          icon: <QrCodeIcon />,
          label: "QR Code Handle",
          path: "/settings/qrCodeHandle",
        },
        {
          icon: <Science />,
          label: "Import Testing",
          path: "/settings/m18ImportTesting",
        },
        {
          icon: <UploadFile />,
          label: "Import Excel",
          path: "/settings/importExcel",
        },
        {
          icon: <UploadFile />,
          label: "Import BOM",
          path: "/settings/importBom",
        },
      ],
    },
  ];
  const { t } = useTranslation("common");
  const pathname = usePathname();

  const [openItems, setOpenItems] = React.useState<string[]>([]);
  // Keep "圖表報告" expanded when on any chart sub-route
  React.useEffect(() => {
    if (pathname.startsWith("/chart/") && !openItems.includes("圖表報告")) {
      setOpenItems((prev) => [...prev, "圖表報告"]);
    }
  }, [pathname, openItems]);
  const toggleItem = (label: string) => {
    setOpenItems((prevOpenItems) =>
      prevOpenItems.includes(label)
        ? prevOpenItems.filter((item) => item !== label)
        : [...prevOpenItems, label],
    );
  };

  const renderNavigationItem = (item: NavigationItem) => {
    if (!hasAbility(item.requiredAbility)) {
      return null;
    }

    const isOpen = openItems.includes(item.label);
    const hasVisibleChildren = item.children?.some(child => hasAbility(child.requiredAbility));
    const isLeaf = Boolean(item.path);
    const isSelected = isLeaf && item.path
      ? pathname === item.path || pathname.startsWith(item.path + "/")
      : hasVisibleChildren && item.children?.some(
          (c) => c.path && (pathname === c.path || pathname.startsWith(c.path + "/"))
        );

    const content = (
      <ListItemButton
        selected={isSelected}
        onClick={isLeaf ? undefined : () => toggleItem(item.label)}
        sx={{
          mx: 1,
          "&.Mui-selected .MuiListItemIcon-root": { color: "primary.main" },
        }}
      >
        <ListItemIcon sx={{ minWidth: 40 }}>{item.icon}</ListItemIcon>
        <ListItemText
          primary={t(item.label)}
          primaryTypographyProps={{ fontWeight: isSelected ? 600 : 500 }}
        />
      </ListItemButton>
    );

    return (
      <Box key={`${item.label}-${item.path}`}>
        {isLeaf ? (
          <Link href={item.path!} style={{ textDecoration: "none", color: "inherit" }}>
            {content}
          </Link>
        ) : (
          content
        )}
        {item.children && isOpen && hasVisibleChildren && (
          <List sx={{ pl: 2, py: 0 }}>
            {item.children.map(
              (child) => !child.isHidden && hasAbility(child.requiredAbility) && (
                <Box
                  key={`${child.label}-${child.path}`}
                  component={Link}
                  href={child.path}
                  sx={{ textDecoration: "none", color: "inherit" }}
                >
                  <ListItemButton
                    selected={pathname === child.path || (!!child.path && pathname.startsWith(child.path + "/"))}
                    sx={{
                      mx: 1,
                      py: 1,
                      "&.Mui-selected .MuiListItemIcon-root": { color: "primary.main" },
                    }}
                  >
                    <ListItemIcon sx={{ minWidth: 40 }}>{child.icon}</ListItemIcon>
                    <ListItemText
                      primary={t(child.label)}
                      primaryTypographyProps={{
                        fontWeight: pathname === child.path || (child.path && pathname.startsWith(child.path + "/")) ? 600 : 500,
                        fontSize: "0.875rem",
                      }}
                    />
                  </ListItemButton>
                </Box>
              ),
            )}
          </List>
        )}
      </Box>
    );
  };

  if (status === "loading") {
    return <Box sx={{ width: NAVIGATION_CONTENT_WIDTH, p: 3 }}>Loading...</Box>;
  }

  return (
    <Box sx={{ width: NAVIGATION_CONTENT_WIDTH, height: "100%", display: "flex", flexDirection: "column" }}>
      <Box
        className="bg-gradient-to-br from-blue-500/15 via-slate-100 to-slate-50 dark:from-blue-500/20 dark:via-slate-800 dark:to-slate-900"
        sx={{
          mx: 1,
          mt: 1,
          mb: 1,
          px: 1.5,
          py: 2,
          flexShrink: 0,
          display: "flex",
          alignItems: "center",
          justifyContent: "flex-start",
          minHeight: 56,
        }}
      >
        <Logo height={42} />
      </Box>
      <Box sx={{ borderTop: 1, borderColor: "divider" }} />
      <List component="nav" sx={{ flex: 1, overflow: "auto", py: 1, px: 0 }}>
        {navigationItems
          .filter(item => !item.isHidden)
          .map(renderNavigationItem)
          .filter(Boolean)}
      </List>
    </Box>
  );
};

export default NavigationContent;