import {
    LayoutDashboard,
    ChevronRight,
    Package,
    ShoppingCart,
    Menu,
    X,
    PanelLeftClose,
    PanelLeftOpen,
    Boxes,
    Warehouse,
    Truck,
    Contact2,
    LogOut,
    User,
    ChevronDown,
    Settings,
    Shield,
    Users,
    FileText,
    Wallet,
    BarChart3,
    FileSpreadsheet,
    BookOpen,
    ClipboardCheck,
    ArrowLeftRight
} from "lucide-react";
import { toast, Toaster } from "sonner";
import { useState, useEffect, useMemo, useRef } from "react";
import { Link, usePage, Head } from "@inertiajs/react";
import { cn } from "@/lib/utils";
import BreadcrumbNav, { BreadcrumbItemType } from "@/Components/shared/BreadcrumbNav";
import {
    DropdownMenu,
    DropdownMenuContent,
    DropdownMenuItem,
    DropdownMenuLabel,
    DropdownMenuSeparator,
    DropdownMenuTrigger,
} from "@/Components/ui/dropdown-menu";
import { usePermission } from "@/hooks/usePermission";
import ApplicationLogo from "@/Components/ApplicationLogo";
import { generateLightestColor, generateLightColor, generateDarkColor, generateActiveColor } from "@/utils/colorUtils";
import { PageProps } from "@/types/global";

interface MenuItem {
    id: string;
    label: string;
    icon?: React.ReactNode;
    route?: string;
    children?: MenuItem[];
    permission?: string | string[];  // 所需權限（單一或多個，滿足任一即可）
}

export default function AuthenticatedLayout({
    children,
    breadcrumbs
}: {
    children: React.ReactNode,
    breadcrumbs?: BreadcrumbItemType[]
}) {
    const { url, props } = usePage<PageProps & { [key: string]: any }>();
    const branding = props.branding;
    const user = props.auth?.user || { name: 'Guest', username: 'guest', roles: [], role_labels: [], permissions: [] };
    const { can, canAny } = usePermission();
    const [isCollapsed, setIsCollapsed] = useState(() => {
        if (typeof window !== "undefined") {
            return localStorage.getItem("sidebar-collapsed") === "true";
        }
        return false;
    });
    const [isMobileOpen, setIsMobileOpen] = useState(false);

    // 完整的菜單定義（含權限配置）
    const allMenuItems: MenuItem[] = [
        {
            id: "dashboard",
            label: "儀表板",
            icon: <LayoutDashboard className="h-5 w-5" />,
            route: "/",
            // 儀表板無需特定權限，所有登入使用者皆可存取
        },
        {
            id: "inventory-management",
            label: "商品與庫存管理",
            icon: <Boxes className="h-5 w-5" />,
            permission: ["products.view", "warehouses.view", "inventory.view"],  // 滿足任一即可看到此群組
            children: [
                {
                    id: "product-management",
                    label: "商品資料管理",
                    icon: <Package className="h-4 w-4" />,
                    route: "/products",
                    permission: "products.view",
                },
                {
                    id: "warehouse-management",
                    label: "倉庫管理",
                    icon: <Warehouse className="h-4 w-4" />,
                    route: "/warehouses",
                    permission: "warehouses.view",
                },
                {
                    id: "stock-counting",
                    label: "庫存盤點",
                    icon: <ClipboardCheck className="h-4 w-4" />,
                    route: "/inventory/count-docs",
                    permission: "inventory_count.view",
                },
                {
                    id: "stock-adjustment",
                    label: "庫存盤調",
                    icon: <FileText className="h-4 w-4" />,
                    route: "/inventory/adjust-docs",
                    permission: "inventory_adjust.view",
                },
                {
                    id: "stock-transfer",
                    label: "庫存調撥",
                    icon: <ArrowLeftRight className="h-4 w-4" />,
                    route: "/inventory/transfer-orders",
                    permission: "inventory_transfer.view",
                },
            ],
        },
        {
            id: "supply-chain-management",
            label: "供應鏈管理",
            icon: <Truck className="h-5 w-5" />,
            permission: ["vendors.view", "purchase_orders.view", "goods_receipts.view"],
            children: [
                {
                    id: "vendor-list",
                    label: "廠商資料管理",
                    icon: <Contact2 className="h-4 w-4" />,
                    route: "/vendors",
                    permission: "vendors.view",
                },
                {
                    id: "purchase-order-list",
                    label: "採購單管理",
                    icon: <ShoppingCart className="h-4 w-4" />,
                    route: "/purchase-orders",
                    permission: "purchase_orders.view",
                },
                {
                    id: "goods-receipt-list",
                    label: "進貨單管理",
                    icon: <ClipboardCheck className="h-4 w-4" />,
                    route: "/goods-receipts",
                    permission: "goods_receipts.view",
                },
                {
                    id: "delivery-note-list",
                    label: "出貨單管理 (功能製作中)",
                    icon: <Package className="h-4 w-4" />,
                    route: "/delivery-notes",
                    permission: "delivery_notes.view",
                },
            ],
        },
        {
            id: "production-management",
            label: "生產管理",
            icon: <Boxes className="h-5 w-5" />,
            permission: ["production_orders.view", "recipes.view"],
            children: [
                {
                    id: "recipe-list",
                    label: "配方管理",
                    icon: <BookOpen className="h-4 w-4" />,
                    route: "/recipes",
                    permission: "recipes.view",
                },
                {
                    id: "production-order-list",
                    label: "生產工單",
                    icon: <Package className="h-4 w-4" />,
                    route: "/production-orders",
                    permission: "production_orders.view",
                },
            ],
        },
        {
            id: "finance-management",
            label: "財務管理",
            icon: <Wallet className="h-5 w-5" />,
            permission: "utility_fees.view",
            children: [
                {
                    id: "utility-fee-list",
                    label: "公共事業費",
                    icon: <FileText className="h-4 w-4" />,
                    route: "/utility-fees",
                    permission: "utility_fees.view",
                },
            ],
        },
        {
            id: "report-management",
            label: "報表管理",
            icon: <BarChart3 className="h-5 w-5" />,
            permission: "accounting.view",
            children: [
                {
                    id: "accounting-report",
                    label: "會計報表",
                    icon: <FileSpreadsheet className="h-4 w-4" />,
                    route: "/accounting-report",
                    permission: "accounting.view",
                },
            ],
        },
        {
            id: "system-management",
            label: "系統管理",
            icon: <Settings className="h-5 w-5" />,
            permission: ["users.view", "roles.view"],
            children: [
                {
                    id: "user-management",
                    label: "使用者管理",
                    icon: <Users className="h-4 w-4" />,
                    route: "/admin/users",
                    permission: "users.view",
                },
                {
                    id: "role-management",
                    label: "角色與權限",
                    icon: <Shield className="h-4 w-4" />,
                    route: "/admin/roles",
                    permission: "roles.view",
                },
                {
                    id: "activity-log",
                    label: "操作紀錄",
                    icon: <FileText className="h-4 w-4" />,
                    route: "/admin/activity-logs",
                    permission: "system.view_logs",
                },
            ],
        },
    ];

    // 檢查單一項目是否有權限
    const hasPermissionForItem = (item: MenuItem): boolean => {
        if (!item.permission) return true;  // 無指定權限則預設有權限
        if (Array.isArray(item.permission)) {
            return canAny(item.permission);
        }
        return can(item.permission);
    };

    // 過濾菜單：移除無權限的項目，若父層所有子項目都無權限則隱藏父層
    const menuItems = useMemo(() => {
        return allMenuItems
            .map((item) => {
                // 如果有子項目，先過濾子項目
                if (item.children && item.children.length > 0) {
                    const filteredChildren = item.children.filter(hasPermissionForItem);
                    // 若所有子項目都無權限，則隱藏整個群組
                    if (filteredChildren.length === 0) return null;
                    return { ...item, children: filteredChildren };
                }
                // 無子項目的單一選單，直接檢查權限
                if (!hasPermissionForItem(item)) return null;
                return item;
            })
            .filter((item): item is MenuItem => item !== null);
    }, [can, canAny]);

    // 初始化狀態：優先讀取 localStorage
    const [expandedItems, setExpandedItems] = useState<string[]>(() => {
        try {
            const saved = localStorage.getItem("sidebar-expanded-items");
            if (saved) return JSON.parse(saved);
        } catch (e) {
            console.error("Failed to parse sidebar state", e);
        }

        // 如果沒有存檔，則預設僅展開當前 URL 對應的群組
        const activeItem = menuItems.find(item =>
            item.children?.some(child => child.route && url.startsWith(child.route))
        );
        const defaultExpanded = ["inventory-management"];
        if (activeItem && !defaultExpanded.includes(activeItem.id)) {
            defaultExpanded.push(activeItem.id);
        }
        return defaultExpanded;
    });

    // 監聽 URL 變化，確保「當前」頁面所屬群組是展開的
    // 但不要影響其他群組的狀態（除非使用者手動切換）
    useEffect(() => {
        const activeItem = menuItems.find(item =>
            item.children?.some(child => child.route && url.startsWith(child.route))
        );

        if (activeItem && !expandedItems.includes(activeItem.id)) {
            setExpandedItems(prev => {
                const next = [...prev, activeItem.id];
                localStorage.setItem("sidebar-expanded-items", JSON.stringify(next));
                return next;
            });
        }
    }, [url]);

    useEffect(() => {
        localStorage.setItem("sidebar-collapsed", String(isCollapsed));
    }, [isCollapsed]);

    // 全域監聽 flash 訊息並顯示 Toast
    const lastFlash = useRef<any>(null);
    useEffect(() => {
        if (!props.flash) return;

        // 檢查是否與上次顯示的訊息相同（透過簡單的物件引用比對，Inertia 在重導向後會產生新的 props 物件）
        if (props.flash === lastFlash.current) return;

        if (props.flash.success) {
            toast.success(props.flash.success);
        }
        if (props.flash.error) {
            toast.error(props.flash.error);
        }

        lastFlash.current = props.flash;
    }, [props.flash]);

    const toggleExpand = (itemId: string) => {
        if (isCollapsed) {
            setIsCollapsed(false);
            if (!expandedItems.includes(itemId)) {
                setExpandedItems(prev => [...prev, itemId]);
            }
            return;
        }

        setExpandedItems((prev) => {
            const next = prev.includes(itemId)
                ? prev.filter((id) => id !== itemId)
                : [...prev, itemId];

            localStorage.setItem("sidebar-expanded-items", JSON.stringify(next));
            return next;
        });
    };

    const renderMenuItem = (item: MenuItem, level: number = 0) => {
        const hasChildren = item.children && item.children.length > 0;
        const isExpanded = expandedItems.includes(item.id);
        const isActive = item.route
            ? (item.route === '/' ? url === '/' : url.startsWith(item.route))
            : false;

        return (
            <div key={item.id} className="mb-1">
                {hasChildren ? (
                    <button
                        onClick={() => toggleExpand(item.id)}
                        className={cn(
                            "w-full flex items-center transition-all rounded-lg group",
                            level === 0 ? "px-3 py-2.5" : "px-3 py-2 pl-10",
                            level === 0 && !isCollapsed && "hover:bg-slate-100",
                            isCollapsed && level === 0 && "justify-center px-0 h-10 w-10 mx-auto hover:bg-slate-100"
                        )}
                        title={isCollapsed ? item.label : ""}
                    >
                        {level === 0 && (
                            <span className={cn(
                                "flex-shrink-0 transition-all",
                                isCollapsed ? "mr-0" : "mr-3 text-slate-500 group-hover:text-slate-900"
                            )}>
                                {item.icon}
                            </span>
                        )}

                        {!isCollapsed && (
                            <>
                                <span className="flex-1 text-left text-base font-medium text-slate-700 group-hover:text-slate-900 truncate">
                                    {item.label}
                                </span>
                                <span className="flex-shrink-0 transition-transform duration-200">
                                    {isExpanded ? (
                                        <ChevronDown className="h-3.5 w-3.5 text-slate-400" />
                                    ) : (
                                        <ChevronRight className="h-3.5 w-3.5 text-slate-400" />
                                    )}
                                </span>
                            </>
                        )}
                    </button>
                ) : (
                    <Link
                        href={item.route || "#"}
                        onClick={() => setIsMobileOpen(false)}
                        className={cn(
                            "w-full flex items-center transition-all rounded-lg group",
                            level === 0 ? "px-3 py-2.5" : "px-3 py-2",
                            level > 0 && !isCollapsed && "pl-11",
                            isActive ? "bg-primary-lightest text-primary-main" : "text-slate-600 hover:bg-slate-100 hover:text-slate-900",
                            isCollapsed && level === 0 && "justify-center px-0 h-10 w-10 mx-auto"
                        )}
                        title={isCollapsed ? item.label : ""}
                    >
                        {item.icon && (
                            <span className={cn(
                                "flex-shrink-0 transition-all",
                                isCollapsed ? "mr-0" : "mr-3",
                                isActive ? "text-primary-main" : "text-slate-500 group-hover:text-slate-900"
                            )}>
                                {item.icon}
                            </span>
                        )}
                        {!isCollapsed && (
                            <span className="text-base font-medium truncate">
                                {item.label}
                            </span>
                        )}
                    </Link>
                )}

                {hasChildren && isExpanded && !isCollapsed && (
                    <div className="mt-1 space-y-1">
                        {item.children?.map((child) => renderMenuItem(child, level + 1))}
                    </div>
                )}
            </div>
        );
    };

    return (
        <div className="flex min-h-screen bg-slate-50">
            <Head>
                <link rel="icon" type="image/png" href="/favicon.png" />
            </Head>
            <style>{`
                :root {
                    --primary-main: ${branding?.primary_color || '#01ab83'};
                    --primary-dark: ${generateDarkColor(branding?.primary_color || '#01ab83')};
                    --primary-light: ${generateLightColor(branding?.primary_color || '#01ab83')};
                    --primary-lightest: ${generateLightestColor(branding?.primary_color || '#01ab83')};
                    --button-main-active: ${generateActiveColor(branding?.primary_color || '#01ab83')};
                }
            `}</style>
            {/* Mobile Header -> Global Header */}
            <header className="fixed top-0 left-0 right-0 h-16 bg-white border-b border-slate-200 z-[60] flex items-center justify-between px-4 transition-all duration-300">
                <div className="flex items-center gap-2">
                    <button
                        onClick={() => setIsMobileOpen(!isMobileOpen)}
                        className="p-2 -ml-2 text-slate-600 hover:bg-slate-100 rounded-lg lg:hidden"
                    >
                        {isMobileOpen ? <X className="h-6 w-6" /> : <Menu className="h-6 w-6" />}
                    </button>
                    <Link href="/" className="flex items-center gap-2">
                        <ApplicationLogo className="w-8 h-8 rounded-lg object-contain" />
                        <span className="font-bold text-slate-900">{branding?.short_name || 'Star'} ERP</span>
                    </Link>
                </div>

                {/* User Menu */}
                <DropdownMenu modal={false}>
                    <DropdownMenuTrigger className="flex items-center gap-2 outline-none group">
                        <div className="hidden md:flex flex-col items-end mr-1">
                            <span className="text-sm font-medium text-slate-700 group-hover:text-slate-900 transition-colors">
                                {user.name} ({user.username})
                            </span>
                            <span className="text-xs text-slate-500">
                                {user.role_labels?.[0] || user.roles?.[0] || '一般用戶'}
                            </span>
                        </div>
                        <div className="h-9 w-9 bg-slate-100 rounded-full flex items-center justify-center text-slate-600 group-hover:bg-primary-lightest group-hover:text-primary-main transition-all">
                            <User className="h-5 w-5" />
                        </div>
                    </DropdownMenuTrigger>
                    <DropdownMenuContent align="end" className="w-56 z-[100]" sideOffset={8}>
                        <DropdownMenuLabel>{user.name} ({user.username})</DropdownMenuLabel>
                        <DropdownMenuSeparator />
                        <DropdownMenuItem asChild>
                            <Link
                                href={route('profile.edit')}
                                className="w-full flex items-center cursor-pointer text-slate-600 focus:bg-slate-100 focus:text-slate-900 group"
                            >
                                <Settings className="mr-2 h-4 w-4 text-slate-500 group-focus:text-slate-900" />
                                <span>使用者設定</span>
                            </Link>
                        </DropdownMenuItem>
                        <DropdownMenuSeparator />
                        <DropdownMenuItem asChild>
                            <Link
                                href={route('logout')}
                                method="post"
                                as="button"
                                className="w-full flex items-center cursor-pointer text-red-600 focus:text-red-600 focus:bg-red-50"
                            >
                                <LogOut className="mr-2 h-4 w-4" />
                                <span>登出系統</span>
                            </Link>
                        </DropdownMenuItem>
                    </DropdownMenuContent>
                </DropdownMenu>
            </header>

            {/* Sidebar Desktop */}
            <aside className={cn(
                "fixed left-0 top-0 bottom-0 bg-white border-r border-slate-200 z-50 transition-all duration-300 ease-in-out hidden lg:flex flex-col pt-16",
                isCollapsed ? "w-20" : "w-64"
            )}>
                <div className="hidden h-16 items-center justify-between px-6 border-b border-slate-100">
                    {!isCollapsed && (
                        <Link href="/" className="flex items-center gap-2 group">
                            <ApplicationLogo className="w-8 h-8 rounded-lg object-contain group-hover:scale-110 transition-transform" />
                            <span className="font-extrabold text-primary-main text-lg tracking-tight">{branding?.short_name || 'Star'} ERP</span>
                        </Link>
                    )}
                    {isCollapsed && (
                        <Link href="/" className="w-8 h-8 mx-auto">
                            <ApplicationLogo className="w-8 h-8 rounded-lg object-contain" />
                        </Link>
                    )}
                </div>

                <div className="flex-1 overflow-y-auto overflow-x-hidden p-4 space-y-6">
                    <nav className="space-y-1">
                        {menuItems.map((item) => renderMenuItem(item))}
                    </nav>
                </div>

                <div className="p-4 border-t border-slate-100 flex items-center justify-between">
                    {!isCollapsed && <p className="text-[10px] font-medium text-slate-400 uppercase tracking-wider px-2">Version 1.0.0</p>}
                    <button
                        onClick={() => setIsCollapsed(!isCollapsed)}
                        className={cn(
                            "p-2 text-slate-400 hover:text-slate-600 hover:bg-slate-50 rounded-lg transition-colors",
                            isCollapsed && "mx-auto"
                        )}
                        title={isCollapsed ? "展開側邊欄" : "縮合側邊欄"}
                    >
                        {isCollapsed ? <PanelLeftOpen className="h-5 w-5" /> : <PanelLeftClose className="h-5 w-5" />}
                    </button>
                </div>
            </aside >

            {/* Mobile Sidebar Overlay */}
            {
                isMobileOpen && (
                    <div
                        className="fixed inset-0 bg-slate-900/50 backdrop-blur-sm z-[70] lg:hidden"
                        onClick={() => setIsMobileOpen(false)}
                    />
                )
            }

            {/* Mobile Sidebar Drawer */}
            <aside className={cn(
                "fixed left-0 top-0 bottom-0 w-72 bg-white z-[80] transition-transform duration-300 ease-in-out lg:hidden flex flex-col shadow-2xl",
                isMobileOpen ? "translate-x-0" : "-translate-x-full"
            )}>
                <div className="h-16 flex items-center justify-between px-6 border-b border-slate-100">
                    <Link href="/" className="flex items-center gap-2">
                        <ApplicationLogo className="w-8 h-8 rounded-lg object-contain" />
                        <span className="font-extrabold text-primary-main text-lg">{branding?.short_name || 'Star'} ERP</span>
                    </Link>
                    <button onClick={() => setIsMobileOpen(false)} className="p-2 text-slate-400">
                        <X className="h-5 w-5" />
                    </button>
                </div>
                <div className="flex-1 overflow-y-auto p-4">
                    <nav className="space-y-1">
                        {menuItems.map((item) => renderMenuItem(item))}
                    </nav>
                </div>
            </aside>

            {/* Main Content */}
            <main className={cn(
                "flex-1 flex flex-col transition-all duration-300 min-h-screen overflow-auto",
                "lg:ml-64",
                isCollapsed && "lg:ml-20",
                "pt-16" // 始終為頁首保留空間
            )}>
                <div className="relative">
                    <div className="container mx-auto px-6 pt-6 max-w-7xl">
                        {breadcrumbs && breadcrumbs.length > 1 && (
                            <BreadcrumbNav items={breadcrumbs} className="mb-2" />
                        )}
                    </div>
                    {children}
                </div>
                <footer className="mt-auto py-6 text-center text-sm text-slate-400">
                    Copyright &copy; {new Date().getFullYear()} {branding?.name || branding?.short_name || 'Star ERP'}. All rights reserved. Design by 星科技
                </footer>
                <Toaster richColors closeButton position="top-center" />
            </main>
        </div >
    );
}