/**
 * 編輯配方頁面
 */

import { useEffect } from "react";
import { BookOpen, Plus, Trash2, ArrowLeft, Save } from 'lucide-react';
import { Button } from "@/Components/ui/button";
import AuthenticatedLayout from "@/Layouts/AuthenticatedLayout";
import { Head, useForm, Link } from "@inertiajs/react";
import { getBreadcrumbs } from "@/utils/breadcrumb";
import { SearchableSelect } from "@/Components/ui/searchable-select";
import { Input } from "@/Components/ui/input";
import { Label } from "@/Components/ui/label";
import { Textarea } from "@/Components/ui/textarea";
import { Table, TableBody, TableCell, TableHead, TableHeader, TableRow } from "@/Components/ui/table";

interface Product {
    id: number;
    name: string;
    code: string;
    base_unit_id?: number;
    large_unit_id?: number;
}

interface Unit {
    id: number;
    name: string;
}

// Backend Model Structure
interface RecipeItemModel {
    id: number;
    product_id: number;
    quantity: number;
    unit_id: number;
    remark: string | null;
    product?: Product;
    unit?: Unit;
}

interface RecipeModel {
    id: number;
    product_id: number;
    code: string;
    name: string;
    description: string | null;
    yield_quantity: number;
    items: RecipeItemModel[];
    product?: Product;
}

// Form State Structure
interface RecipeItemForm {
    product_id: string;
    quantity: string;
    unit_id: string;
    remark: string;
    // UI Helpers
    ui_product_name?: string;
    ui_product_code?: string;
    ui_unit_name?: string;
}

interface Props {
    recipe: RecipeModel;
    products: Product[];
    units: Unit[];
}

export default function RecipeEdit({ recipe, products, units }: Props) {
    const { data, setData, put, processing, errors } = useForm({
        product_id: String(recipe.product_id),
        code: recipe.code,
        name: recipe.name,
        description: recipe.description || "",
        yield_quantity: String(recipe.yield_quantity),
        items: recipe.items.map(item => ({
            product_id: String(item.product_id),
            quantity: String(item.quantity),
            unit_id: String(item.unit_id),
            remark: item.remark || "",
            ui_product_name: item.product?.name,
            ui_product_code: item.product?.code,
            ui_unit_name: item.unit?.name
        })) as RecipeItemForm[],
    });

    // 自動產生配方名稱 (當選擇商品時) - 僅在名稱為空時觸發，避免覆蓋舊資料
    useEffect(() => {
        if (data.product_id && !data.name) {
            const product = products.find(p => String(p.id) === data.product_id);
            if (product) {
                setData(d => ({ ...d, name: `${product.name} 標準配方` }));
            }
        }
    }, [data.product_id]);

    const addItem = () => {
        setData('items', [
            ...data.items,
            { product_id: "", quantity: "1", unit_id: "", remark: "" }
        ]);
    };

    const removeItem = (index: number) => {
        setData('items', data.items.filter((_, i) => i !== index));
    };

    const updateItem = (index: number, field: keyof RecipeItemForm, value: string) => {
        const newItems = [...data.items];
        newItems[index] = { ...newItems[index], [field]: value };

        // Auto-fill unit when product selected
        if (field === 'product_id') {
            const product = products.find(p => String(p.id) === value);
            if (product) {
                newItems[index].ui_product_name = product.name;
                newItems[index].ui_product_code = product.code;
                // Default to base unit if not set
                if (product.base_unit_id) {
                    newItems[index].unit_id = String(product.base_unit_id);
                    const unit = units.find(u => u.id === product.base_unit_id);
                    newItems[index].ui_unit_name = unit?.name;
                }
            }
        }

        setData('items', newItems);
    };

    const handleSubmit = (e: React.FormEvent) => {
        e.preventDefault();
        put(route('recipes.update', recipe.id));
    };

    return (
        <AuthenticatedLayout breadcrumbs={getBreadcrumbs("recipes", [{ label: "編輯", isPage: true }])}>
            <Head title="編輯配方" />
            <div className="container mx-auto p-6 max-w-7xl">
                <div className="mb-6">
                    <Link href={route('recipes.index')}>
                        <Button
                            variant="outline"
                            className="gap-2 button-outlined-primary mb-6"
                        >
                            <ArrowLeft className="h-4 w-4" />
                            返回列表
                        </Button>
                    </Link>

                    <div className="flex items-center justify-between">
                        <div>
                            <h1 className="text-2xl font-bold text-grey-0 flex items-center gap-2">
                                <BookOpen className="h-6 w-6 text-primary-main" />
                                編輯配方
                            </h1>
                            <p className="text-gray-500 mt-1">
                                修改 {recipe.name} ({recipe.code})
                            </p>
                        </div>
                        <Button
                            onClick={handleSubmit}
                            disabled={processing}
                            className="button-filled-primary gap-2"
                        >
                            <Save className="h-4 w-4" />
                            儲存變更
                        </Button>
                    </div>
                </div>

                <div className="grid grid-cols-1 lg:grid-cols-3 gap-6">
                    {/* 左側：基本資料 */}
                    <div className="lg:col-span-1 space-y-6">
                        <div className="bg-white p-6 rounded-lg shadow-sm border border-gray-200">
                            <h2 className="text-lg font-semibold mb-4">基本資料</h2>
                            <div className="space-y-4">
                                <div className="space-y-1">
                                    <Label className="text-xs font-medium text-grey-2">對應成品 *</Label>
                                    <SearchableSelect
                                        value={data.product_id}
                                        onValueChange={(v) => setData('product_id', v)}
                                        options={products.map(p => ({
                                            label: `${p.name} (${p.code})`,
                                            value: String(p.id),
                                        }))}
                                        placeholder="選擇商品"
                                        className="w-full"
                                    />
                                    {errors.product_id && <p className="text-red-500 text-xs">{errors.product_id}</p>}
                                </div>

                                <div className="space-y-1">
                                    <Label className="text-xs font-medium text-grey-2">配方代號 *</Label>
                                    <Input
                                        value={data.code}
                                        onChange={(e) => setData('code', e.target.value)}
                                        placeholder="例如: REC-P001"
                                    />
                                    {errors.code && <p className="text-red-500 text-xs">{errors.code}</p>}
                                </div>

                                <div className="space-y-1">
                                    <Label className="text-xs font-medium text-grey-2">配方名稱 *</Label>
                                    <Input
                                        value={data.name}
                                        onChange={(e) => setData('name', e.target.value)}
                                        placeholder="例如: 草莓冰標準配方"
                                    />
                                    {errors.name && <p className="text-red-500 text-xs">{errors.name}</p>}
                                </div>

                                <div className="space-y-1">
                                    <Label className="text-xs font-medium text-grey-2">標準產出量 *</Label>
                                    <div className="flex items-center gap-2">
                                        <Input
                                            type="number"
                                            step="any"
                                            value={data.yield_quantity}
                                            onChange={(e) => setData('yield_quantity', e.target.value)}
                                            placeholder="1"
                                        />
                                        <span className="text-sm text-gray-500">份</span>
                                    </div>
                                    {errors.yield_quantity && <p className="text-red-500 text-xs">{errors.yield_quantity}</p>}
                                </div>

                                <div className="space-y-1">
                                    <Label className="text-xs font-medium text-grey-2">描述</Label>
                                    <Textarea
                                        value={data.description}
                                        onChange={(e) => setData('description', e.target.value)}
                                        placeholder="備註說明..."
                                        rows={3}
                                    />
                                </div>
                            </div>
                        </div>
                    </div>

                    {/* 右側：配方明細 */}
                    <div className="lg:col-span-2">
                        <div className="bg-white p-6 rounded-lg shadow-sm border border-gray-200 h-full">
                            <div className="flex items-center justify-between mb-4">
                                <h2 className="text-lg font-semibold">配方明細 (BOM)</h2>
                                <Button
                                    type="button"
                                    variant="outline"
                                    onClick={addItem}
                                    className="gap-2 button-filled-primary text-white"
                                >
                                    <Plus className="h-4 w-4" />
                                    新增原料
                                </Button>
                            </div>

                            <div className="border rounded-lg overflow-hidden">
                                <Table>
                                    <TableHeader className="bg-gray-50">
                                        <TableRow>
                                            <TableHead className="w-[35%]">原物料商品</TableHead>
                                            <TableHead className="w-[20%]">標準用量</TableHead>
                                            <TableHead className="w-[20%]">單位</TableHead>
                                            <TableHead className="w-[20%]">備註</TableHead>
                                            <TableHead className="w-[5%]"></TableHead>
                                        </TableRow>
                                    </TableHeader>
                                    <TableBody>
                                        {data.items.length === 0 ? (
                                            <TableRow>
                                                <TableCell colSpan={5} className="h-24 text-center text-gray-500">
                                                    請新增原物料項目
                                                </TableCell>
                                            </TableRow>
                                        ) : (
                                            data.items.map((item, index) => (
                                                <TableRow key={index}>
                                                    <TableCell className="align-top">
                                                        <SearchableSelect
                                                            value={item.product_id}
                                                            onValueChange={(v) => updateItem(index, 'product_id', v)}
                                                            options={products.map(p => ({
                                                                label: `${p.name} (${p.code})`,
                                                                value: String(p.id)
                                                            }))}
                                                            placeholder="選擇原料"
                                                            className="w-full"
                                                        />
                                                    </TableCell>
                                                    <TableCell className="align-top">
                                                        <Input
                                                            type="number"
                                                            step="any"
                                                            value={item.quantity}
                                                            onChange={(e) => updateItem(index, 'quantity', e.target.value)}
                                                            placeholder="數量"
                                                            className="text-right"
                                                        />
                                                    </TableCell>
                                                    <TableCell className="align-middle">
                                                        <div className="text-sm text-gray-700 bg-gray-50 px-3 py-2 rounded-md border border-gray-100 min-h-[38px] flex items-center">
                                                            {item.ui_unit_name || (units.find(u => String(u.id) === item.unit_id)?.name) || '-'}
                                                        </div>
                                                    </TableCell>
                                                    <TableCell className="align-top">
                                                        <Input
                                                            value={item.remark}
                                                            onChange={(e) => updateItem(index, 'remark', e.target.value)}
                                                            placeholder="備註"
                                                        />
                                                    </TableCell>
                                                    <TableCell className="align-top">
                                                        <Button
                                                            variant="ghost"
                                                            size="sm"
                                                            onClick={() => removeItem(index)}
                                                            className="text-red-500 hover:text-red-700 hover:bg-red-50"
                                                        >
                                                            <Trash2 className="h-4 w-4" />
                                                        </Button>
                                                    </TableCell>
                                                </TableRow>
                                            ))
                                        )}
                                    </TableBody>
                                </Table>
                            </div>
                            {errors.items && <p className="text-red-500 text-sm mt-2">{errors.items}</p>}
                        </div>
                    </div>
                </div>
            </div>
        </AuthenticatedLayout>
    );
}