"use client";

import Image from "next/image";
import Link from "next/link";
import { useRouter } from "next/navigation";
import { ChangeEvent, FormEvent, useEffect, useMemo, useRef, useState } from "react";
import ClothesShell from "@/components/clothes/ClothesShell";
import CategoryTreeSelect from "@/components/ui/CategoryTreeSelect";
import ImageCropper from "@/components/ui/ImageCropper";
import PriceInput from "@/components/ui/PriceInput";
import type { Brand, CategoryNode, TechnicalData } from "@/data/clothes";
import {
  parsePriceInput,
  resolveCategoryTechnicalFields,
} from "@/data/clothes";
import { ApiError, uploadMedia } from "@/lib/api";
import {
  createProduct,
  fetchBrands,
  fetchCategoriesTree,
} from "@/lib/clothes-api";

export default function AddProductPage() {
  const router = useRouter();
  const coverRef = useRef<HTMLInputElement>(null);
  const galleryRef = useRef<HTMLInputElement>(null);

  const [categoryTree, setCategoryTree] = useState<CategoryNode[]>([]);
  const [brands, setBrands] = useState<Brand[]>([]);
  const [categoryId, setCategoryId] = useState("");
  const [brandId, setBrandId] = useState("");
  const [nameFa, setNameFa] = useState("");
  const [nameEn, setNameEn] = useState("");
  const [price, setPrice] = useState("");
  const [abstract, setAbstract] = useState("");
  const [desc, setDesc] = useState("");
  const [tags, setTags] = useState<string[]>([]);
  const [tagInput, setTagInput] = useState("");
  const [technicalData, setTechnicalData] = useState<TechnicalData>({});
  const [coverPreview, setCoverPreview] = useState(
    "/images/ahmad-ebadi-r5IzkiO08JU-unsplash.jpg",
  );
  const [coverFile, setCoverFile] = useState<File | null>(null);
  const [galleryItems, setGalleryItems] = useState<
    Array<{ preview: string; file: File }>
  >([]);
  const [saving, setSaving] = useState(false);
  const [error, setError] = useState<string | null>(null);
  const [loadingMeta, setLoadingMeta] = useState(true);

  const technicalFields = useMemo(
    () =>
      categoryId
        ? resolveCategoryTechnicalFields(categoryId, categoryTree)
        : [],
    [categoryId, categoryTree],
  );

  useEffect(() => {
    setTechnicalData((prev) => {
      const next: TechnicalData = {};
      for (const field of technicalFields) {
        next[field.id] = prev[field.id] ?? "";
      }
      return next;
    });
  }, [technicalFields]);

  useEffect(() => {
    let cancelled = false;
    (async () => {
      try {
        const [cats, brandRows] = await Promise.all([
          fetchCategoriesTree(),
          fetchBrands(),
        ]);
        if (cancelled) return;
        setCategoryTree(cats);
        setBrands(brandRows);
      } catch (err) {
        if (!cancelled) {
          setError(
            err instanceof ApiError
              ? err.message
              : "بارگذاری دسته‌ها و برندها ناموفق بود.",
          );
        }
      } finally {
        if (!cancelled) setLoadingMeta(false);
      }
    })();
    return () => {
      cancelled = true;
    };
  }, []);

  function addTag() {
    const next = tagInput.trim();
    if (!next || tags.includes(next)) return;
    setTags((prev) => [...prev, next]);
    setTagInput("");
  }

  function handleCoverChange(event: ChangeEvent<HTMLInputElement>) {
    const file = event.target.files?.[0];
    if (!file) return;
    setCoverFile(file);
    setCoverPreview(URL.createObjectURL(file));
  }

  function handleGalleryChange(event: ChangeEvent<HTMLInputElement>) {
    const files = event.target.files;
    if (!files?.length) return;
    const next = Array.from(files).map((file) => ({
      preview: URL.createObjectURL(file),
      file,
    }));
    setGalleryItems((prev) => [...prev, ...next]);
    event.target.value = "";
  }

  async function handleSubmit(event: FormEvent) {
    event.preventDefault();
    if (!nameFa.trim()) {
      setError("نام فارسی الزامی است.");
      return;
    }

    const priceTrimmed = parsePriceInput(price);
    const priceNum = priceTrimmed ? Number(priceTrimmed) : 0;
    if (priceTrimmed && (!Number.isFinite(priceNum) || priceNum < 0)) {
      setError("قیمت معتبر وارد کنید.");
      return;
    }

    const missingRequired = technicalFields.find(
      (field) => field.required && !(technicalData[field.id] ?? "").trim(),
    );
    if (missingRequired) {
      setError(`فیلد «${missingRequired.labelFa}» الزامی است.`);
      return;
    }

    setSaving(true);
    setError(null);
    try {
      let imageUrl: string | undefined;
      let imageKey: string | undefined;
      if (coverFile) {
        const uploaded = await uploadMedia(coverFile, "main");
        imageUrl = uploaded.url;
        imageKey = uploaded.storageKey;
      }

      const galleryUrls: string[] = [];
      const galleryKeys: string[] = [];
      for (const item of galleryItems) {
        const uploaded = await uploadMedia(item.file, "gallery");
        galleryUrls.push(uploaded.url);
        galleryKeys.push(uploaded.storageKey);
      }

      const cleanedTechnical: TechnicalData = {};
      for (const field of technicalFields) {
        const value = (technicalData[field.id] ?? "").trim();
        if (value) cleanedTechnical[field.id] = value;
      }

      const roundedPrice = Math.round(priceNum);
      await createProduct({
        nameFa: nameFa.trim(),
        nameEn: nameEn.trim() || undefined,
        summary: abstract.trim() || undefined,
        description: desc.trim() || undefined,
        price: roundedPrice,
        categoryId: categoryId ? Number(categoryId) : undefined,
        brandId: brandId || undefined,
        tags,
        imageUrl,
        imageKey,
        galleryUrls,
        galleryKeys,
        published: true,
        technicalData: cleanedTechnical,
        ...(priceTrimmed
          ? {
              variants: [
                {
                  colorId: "",
                  sizeId: "",
                  packageId: "",
                  price: roundedPrice,
                },
              ],
            }
          : {}),
      });

      router.push("/clothes/list");
      router.refresh();
    } catch (err) {
      setError(
        err instanceof ApiError ? err.message : "ثبت محصول ناموفق بود.",
      );
    } finally {
      setSaving(false);
    }
  }

  return (
    <ClothesShell
      eyebrow="New Product"
      title="افزودن لباس"
      description="کاور را برش دهید، اطلاعات محصول را کامل کنید و گالری را اضافه کنید."
      breadcrumbs={[
        { label: "داشبورد", href: "/" },
        { label: "لباس‌ها", href: "/clothes" },
        { label: "فهرست", href: "/clothes/list" },
        { label: "افزودن" },
      ]}
    >
      <form
        onSubmit={handleSubmit}
        className="grid grid-cols-1 gap-3 lg:grid-cols-[280px_1fr]"
      >
        <aside className="dash-enter rounded-lg border border-line bg-surface p-4">
          <p className="mb-3 text-sm text-ink">برش تصویر کاور</p>
          <p className="mb-4 text-xs leading-6 text-muted">
            نسبت ۲:۳ — زوم را کم کنید تا کل سوژه در قاب بماند؛ قاب داخلی محدوده نمایش است.
          </p>
          <ImageCropper
            src={coverPreview}
            aspect="2:3"
            focusY={0}
            alt="پیش‌نمایش کاور"
            className="product-cover-cropper"
          />
          <input
            ref={coverRef}
            type="file"
            accept="image/jpeg,image/png,image/webp"
            className="sr-only"
            onChange={handleCoverChange}
          />
          <button
            type="button"
            className="mt-4 w-full border border-line bg-white px-3 py-2 text-sm text-ink transition-colors hover:border-ink"
            onClick={() => coverRef.current?.click()}
          >
            انتخاب تصویر کاور
          </button>
        </aside>

        <div className="space-y-3 dash-enter" style={{ animationDelay: "70ms" }}>
          {error ? (
            <p className="rounded-lg border border-line bg-white px-4 py-3 text-sm text-ink">
              {error}
            </p>
          ) : null}
          {loadingMeta ? (
            <p className="text-sm text-muted">در حال بارگذاری...</p>
          ) : null}

          <section className="grid grid-cols-1 gap-3 rounded-lg border border-line bg-surface p-4 sm:grid-cols-12">
            <div className="clothes-field sm:col-span-8">
              <label htmlFor="category">دسته‌بندی</label>
              <CategoryTreeSelect
                id="category"
                nodes={categoryTree}
                value={categoryId}
                onChange={setCategoryId}
              />
            </div>
            <div className="clothes-field sm:col-span-4">
              <label htmlFor="brand">برند</label>
              <select
                id="brand"
                value={brandId}
                onChange={(e) => setBrandId(e.target.value)}
              >
                <option value="">انتخاب کنید</option>
                {brands.map((brand) => (
                  <option key={brand.id} value={brand.id}>
                    {brand.nameFa} / {brand.nameEn}
                  </option>
                ))}
              </select>
            </div>
            <div className="clothes-field sm:col-span-6">
              <label htmlFor="name-fa">نام فارسی</label>
              <input
                id="name-fa"
                value={nameFa}
                onChange={(e) => setNameFa(e.target.value)}
                placeholder="مثلاً مانتو مشکی کلاسیک"
                required
              />
            </div>
            <div className="clothes-field sm:col-span-6">
              <label htmlFor="name-en">نام انگلیسی</label>
              <input
                id="name-en"
                dir="ltr"
                value={nameEn}
                onChange={(e) => setNameEn(e.target.value)}
                placeholder="Classic Black Manteau"
              />
            </div>
            <div className="clothes-field sm:col-span-6">
              <label htmlFor="price">قیمت (IRT)</label>
              <PriceInput
                id="price"
                className="font-montserrat"
                value={price}
                onChange={setPrice}
                placeholder="1,250,000"
              />
            </div>
            <div className="clothes-field sm:col-span-12">
              <label htmlFor="abstract">خلاصه</label>
              <textarea
                id="abstract"
                value={abstract}
                onChange={(e) => setAbstract(e.target.value)}
                placeholder="توضیح کوتاه برای کارت محصول..."
                className="!min-h-[4.5rem]"
              />
            </div>
            <div className="clothes-field sm:col-span-12">
              <label htmlFor="desc">توضیحات</label>
              <textarea
                id="desc"
                value={desc}
                onChange={(e) => setDesc(e.target.value)}
                placeholder="جزئیات کامل محصول..."
              />
            </div>
          </section>

          {technicalFields.length > 0 ? (
            <section className="rounded-lg border border-line bg-surface p-4">
              <div className="mb-3">
                <p className="text-sm text-ink">مشخصات فنی</p>
                <p className="text-xs text-muted">
                  فیلدهای تعریف‌شده برای این دسته‌بندی
                </p>
              </div>
              <div className="grid grid-cols-1 gap-3 sm:grid-cols-2">
                {technicalFields.map((field) => (
                  <div key={field.id} className="clothes-field">
                    <label htmlFor={`tech-${field.id}`}>
                      {field.labelFa}
                      {field.required ? " *" : ""}
                      {field.labelEn ? (
                        <span
                          dir="ltr"
                          className="ms-1 font-montserrat text-[0.7rem] text-muted"
                        >
                          ({field.labelEn})
                        </span>
                      ) : null}
                    </label>
                    <input
                      id={`tech-${field.id}`}
                      value={technicalData[field.id] ?? ""}
                      onChange={(e) =>
                        setTechnicalData((prev) => ({
                          ...prev,
                          [field.id]: e.target.value,
                        }))
                      }
                      required={field.required}
                      placeholder={field.labelFa}
                    />
                  </div>
                ))}
              </div>
            </section>
          ) : null}

          <section className="rounded-lg border border-line bg-surface p-4">
            <div className="mb-3 flex items-center justify-between gap-3">
              <div>
                <p className="text-sm text-ink">گالری تصاویر</p>
                <p className="text-xs text-muted">چند تصویر برای جزئیات محصول</p>
              </div>
              <input
                ref={galleryRef}
                type="file"
                accept="image/jpeg,image/png,image/webp"
                multiple
                className="sr-only"
                onChange={handleGalleryChange}
              />
              <button
                type="button"
                className="border border-line px-3 py-1.5 text-xs text-ink hover:border-ink"
                onClick={() => galleryRef.current?.click()}
              >
                آپلود تصویر
              </button>
            </div>
            <div className="gallery-grid">
              {galleryItems.map((item, index) => (
                <div
                  key={item.preview}
                  className="relative overflow-hidden rounded-lg"
                >
                  <Image
                    src={item.preview}
                    alt=""
                    width={160}
                    height={160}
                    unoptimized
                    className="aspect-square h-full w-full object-cover"
                  />
                  <button
                    type="button"
                    className="absolute top-1 start-1 bg-ink/80 px-1.5 text-xs text-white"
                    onClick={() =>
                      setGalleryItems((prev) =>
                        prev.filter((_, i) => i !== index),
                      )
                    }
                  >
                    ×
                  </button>
                </div>
              ))}
              <button
                type="button"
                className="gallery-slot"
                onClick={() => galleryRef.current?.click()}
              >
                + افزودن
              </button>
            </div>
          </section>

          <section className="rounded-lg border border-line bg-surface p-4">
            <p className="mb-3 text-sm text-ink">برچسب‌ها</p>
            <div className="mb-3 flex flex-wrap gap-2">
              {tags.map((tag) => (
                <span key={tag} className="tag-chip">
                  {tag}
                  <button
                    type="button"
                    className="text-muted hover:text-ink"
                    onClick={() =>
                      setTags((prev) => prev.filter((item) => item !== tag))
                    }
                  >
                    ×
                  </button>
                </span>
              ))}
            </div>
            <div className="flex gap-2">
              <input
                value={tagInput}
                onChange={(e) => setTagInput(e.target.value)}
                onKeyDown={(e) => {
                  if (e.key === "Enter") {
                    e.preventDefault();
                    addTag();
                  }
                }}
                placeholder="برچسب جدید"
                className="flex-1 border border-line px-3 py-2 text-sm outline-none focus:border-ink"
              />
              <button
                type="button"
                onClick={addTag}
                className="border border-ink bg-ink px-4 py-2 text-sm text-white hover:bg-white hover:text-ink"
              >
                افزودن
              </button>
            </div>
          </section>

          <div className="flex justify-end gap-2">
            <Link
              href="/clothes/list"
              className="border border-line px-5 py-2.5 text-sm text-muted hover:text-ink"
            >
              انصراف
            </Link>
            <button
              type="submit"
              disabled={saving || loadingMeta}
              className="auth-button !mt-0 !max-w-none !w-auto px-6 disabled:opacity-60"
            >
              <span>{saving ? "در حال ثبت..." : "ثبت محصول"}</span>
            </button>
          </div>
        </div>
      </form>
    </ClothesShell>
  );
}