import { useEffect } from "react";
import { Wand2 } from "lucide-react";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/Components/ui/dialog";
import { Button } from "@/Components/ui/button";
import { Input } from "@/Components/ui/input";
import { Label } from "@/Components/ui/label";
import { Textarea } from "@/Components/ui/textarea";
import { SearchableSelect } from "@/Components/ui/searchable-select";
import { useForm } from "@inertiajs/react";
import { toast } from "sonner";
import type { Product, Category } from "@/Pages/Product/Index";
import type { Unit } from "@/Components/Unit/UnitManagerDialog";


interface ProductDialogProps {
  open: boolean;
  onOpenChange: (open: boolean) => void;
  product: Product | null;
  categories: Category[];
  units: Unit[];
  onSave?: (product: any) => void; // Legacy prop, can be removed if fully switching to Inertia submit within dialog
}

export default function ProductDialog({
  open,
  onOpenChange,
  product,
  categories,
  units,
}: ProductDialogProps) {
  const { data, setData, post, put, processing, errors, reset, clearErrors } = useForm({
    code: "",
    barcode: "",
    name: "",
    category_id: "",
    brand: "",
    specification: "",
    base_unit_id: "",
    large_unit_id: "",
    conversion_rate: "",
    purchase_unit_id: "",
  });

  useEffect(() => {
    if (open) {
      clearErrors();
      if (product) {
        setData({
          code: product.code,
          barcode: product.barcode || "",
          name: product.name,
          category_id: product.categoryId.toString(),
          brand: product.brand || "",
          specification: product.specification || "",
          base_unit_id: product.baseUnitId?.toString() || "",
          large_unit_id: product.largeUnitId?.toString() || "",
          conversion_rate: product.conversionRate ? product.conversionRate.toString() : "",
          purchase_unit_id: product.purchaseUnitId?.toString() || "",
        });
      } else {
        reset();
        // Set default category if available
        if (categories.length > 0) {
          setData("category_id", categories[0].id.toString());
        }
      }
    }
  }, [open, product, categories]);

  const handleSubmit = (e: React.FormEvent) => {
    e.preventDefault();

    if (product) {
      put(route("products.update", product.id), {
        onSuccess: () => {
          toast.success("商品已更新");
          onOpenChange(false);
          reset();
        },
        onError: () => {
          toast.error("更新失敗，請檢查輸入資料");
        }
      });
    } else {
      post(route("products.store"), {
        onSuccess: () => {
          toast.success("商品已新增");
          onOpenChange(false);
          reset();
        },
        onError: () => {
          toast.error("新增失敗，請檢查輸入資料");
        }
      });
    }
  };

  const generateRandomBarcode = () => {
    const randomDigits = Math.floor(Math.random() * 9000000000) + 1000000000;
    setData("barcode", randomDigits.toString());
  };

  return (
    <Dialog open={open} onOpenChange={onOpenChange}>
      <DialogContent className="max-w-3xl max-h-[90vh] overflow-y-auto">
        <DialogHeader>
          <DialogTitle>{product ? "編輯商品" : "新增商品"}</DialogTitle>
          <DialogDescription>
            {product ? "修改商品資料" : "建立新的商品資料"}
          </DialogDescription>
        </DialogHeader>

        <form onSubmit={handleSubmit} className="space-y-6 py-4">

          {/* 基本資訊區塊 */}
          <div className="space-y-4">
            <h3 className="text-lg font-medium border-b pb-2">基本資訊</h3>
            <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
              <div className="space-y-2">
                <Label htmlFor="category_id">
                  分類 <span className="text-red-500">*</span>
                </Label>
                <SearchableSelect
                  value={data.category_id}
                  onValueChange={(value) => setData("category_id", value)}
                  options={categories.map((c) => ({ label: c.name, value: c.id.toString() }))}
                  placeholder="選擇分類"
                  searchPlaceholder="搜尋分類..."
                  className={errors.category_id ? "border-red-500" : ""}
                />
                {errors.category_id && <p className="text-sm text-red-500">{errors.category_id}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="name">
                  商品名稱 <span className="text-red-500">*</span>
                </Label>
                <Input
                  id="name"
                  value={data.name}
                  onChange={(e) => setData("name", e.target.value)}
                  placeholder="例：法國麵粉"
                  className={errors.name ? "border-red-500" : ""}
                />
                {errors.name && <p className="text-sm text-red-500">{errors.name}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="code">
                  商品代號 <span className="text-red-500">*</span>
                </Label>
                <Input
                  id="code"
                  value={data.code}
                  onChange={(e) => setData("code", e.target.value)}
                  placeholder="例：A1 (2-8碼)"
                  maxLength={8}
                  className={errors.code ? "border-red-500" : ""}
                />
                {errors.code && <p className="text-sm text-red-500">{errors.code}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="barcode">
                  條碼編號 <span className="text-red-500">*</span>
                </Label>
                <div className="flex gap-2">
                  <Input
                    id="barcode"
                    value={data.barcode}
                    onChange={(e) => setData("barcode", e.target.value)}
                    onKeyDown={(e) => {
                      if (e.key === 'Enter') {
                        e.preventDefault();
                        // 掃描後自動跳轉到下一個欄位（品牌）
                        document.getElementById('brand')?.focus();
                      }
                    }}
                    placeholder="輸入條碼或自動生成"
                    className={`flex-1 ${errors.barcode ? "border-red-500" : ""}`}
                  />
                  <Button
                    type="button"
                    variant="outline"
                    size="icon"
                    onClick={generateRandomBarcode}
                    title="隨機生成條碼"
                    className="shrink-0 button-outlined-primary"
                  >
                    <Wand2 className="h-4 w-4" />
                  </Button>
                </div>
                {errors.barcode && <p className="text-sm text-red-500">{errors.barcode}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="brand">品牌</Label>
                <Input
                  id="brand"
                  value={data.brand}
                  onChange={(e) => setData("brand", e.target.value)}
                  placeholder="例：鳥越製粉"
                />
                {errors.brand && <p className="text-sm text-red-500">{errors.brand}</p>}
              </div>

              <div className="space-y-2 col-span-2">
                <Label htmlFor="specification">規格描述</Label>
                <Textarea
                  id="specification"
                  value={data.specification}
                  onChange={(e) => setData("specification", e.target.value)}
                  placeholder="例：25kg/袋，灰分0.45%"
                  className="resize-none"
                />
                {errors.specification && <p className="text-sm text-red-500">{errors.specification}</p>}
              </div>
            </div>
          </div>

          {/* 單位設定區塊 */}
          <div className="space-y-4">
            <h3 className="text-lg font-medium border-b pb-2">單位設定</h3>
            <div className="grid grid-cols-1 md:grid-cols-3 gap-4">
              <div className="space-y-2">
                <Label htmlFor="base_unit_id">
                  基本庫存單位 <span className="text-red-500">*</span>
                </Label>
                <SearchableSelect
                  value={data.base_unit_id}
                  onValueChange={(value) => setData("base_unit_id", value)}
                  options={units.map((u) => ({ label: u.name, value: u.id.toString() }))}
                  placeholder="選擇單位"
                  searchPlaceholder="搜尋單位..."
                  className={errors.base_unit_id ? "border-red-500" : ""}
                />
                {errors.base_unit_id && <p className="text-sm text-red-500">{errors.base_unit_id}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="large_unit_id">大單位</Label>
                <SearchableSelect
                  value={data.large_unit_id}
                  onValueChange={(value) => setData("large_unit_id", value)}
                  options={[
                    { label: "無", value: "none" },
                    ...units.map((u) => ({ label: u.name, value: u.id.toString() }))
                  ]}
                  placeholder="無"
                  searchPlaceholder="搜尋單位..."
                  className={errors.large_unit_id ? "border-red-500" : ""}
                />
                {errors.large_unit_id && <p className="text-sm text-red-500">{errors.large_unit_id}</p>}
              </div>

              <div className="space-y-2">
                <Label htmlFor="conversion_rate">
                  換算率
                  {data.large_unit_id && <span className="text-red-500">*</span>}
                </Label>
                <Input
                  id="conversion_rate"
                  type="number"
                  step="0.0001"
                  value={data.conversion_rate}
                  onChange={(e) => setData("conversion_rate", e.target.value)}
                  placeholder={data.large_unit_id && data.base_unit_id ? `1 ${units.find(u => u.id.toString() === data.large_unit_id)?.name} = ? ${units.find(u => u.id.toString() === data.base_unit_id)?.name}` : ""}
                  disabled={!data.large_unit_id}
                />
                {errors.conversion_rate && <p className="text-sm text-red-500">{errors.conversion_rate}</p>}
              </div>

            </div>

            {data.large_unit_id && data.base_unit_id && data.conversion_rate && (
              <div className="bg-blue-50 p-3 rounded text-sm text-blue-700">
                預覽：1 {units.find(u => u.id.toString() === data.large_unit_id)?.name} = {data.conversion_rate} {units.find(u => u.id.toString() === data.base_unit_id)?.name}
              </div>
            )}
          </div>

          <DialogFooter>
            <Button
              type="button"
              variant="outline"
              onClick={() => onOpenChange(false)}
              className="button-outlined-primary"
            >
              取消
            </Button>
            <Button type="submit" className="button-filled-primary" disabled={processing}>
              {processing ? "儲存... " : (product ? "儲存變更" : "新增")}
            </Button>
          </DialogFooter>
        </form>
      </DialogContent>
    </Dialog >
  );
}