import { useMemo, useState } from "react";
import { useTranslation } from "react-i18next";
import { MAIL_REQUEST_FROM } from "@/mailFrom";
import { mailApi } from "@/landing/lib/api";
import { productOptionsFromT } from "@/landing/lib/productLabels";
import type { Product } from "@/landing/types";
import { Button } from "@/landing/ui/Button";
import { CheckboxesGroup } from "@/landing/ui/CheckboxesGroup";
import { ruPhoneDigits } from "@/landing/lib/phoneRu";
import { INTL_PHONE_MAX_DIGITS } from "@/landing/lib/phoneIntl";
import { PhoneInputIntl } from "@/landing/ui/PhoneInputIntl";
import { PhoneInputRu } from "@/landing/ui/PhoneInputRu";
import { useRefererStore } from "@/landing/stores/useRefererStore";
import {
  Controller,
  FormProvider,
  useForm,
  type SubmitHandler,
} from "react-hook-form";
import type { LeadFormValues } from "./types";

export type { LeadFormValues } from "./types";

export function LeadForm({
  defaultProducts,
  idPrefix = "",
  onSuccess,
  phonePlaceholder,
  formClassName = "lg:space-y-[1.944vw] md:max-lg:space-y-7 space-y-3",
}: {
  defaultProducts: Product[];
  /** Префикс для id полей (например `modal-`), чтобы избежать дублей в DOM */
  idPrefix?: string;
  onSuccess: (id: string) => void;
  phonePlaceholder?: string;
  formClassName?: string;
}) {
  const { t, i18n } = useTranslation();
  const isRuLocale = i18n.language.startsWith("ru");
  const { referer } = useRefererStore();
  const [submitError, setSubmitError] = useState<string | null>(null);
  const projectOptions = useMemo(() => productOptionsFromT(t), [t]);

  const form = useForm<LeadFormValues>({
    defaultValues: {
      fullname: "",
      email: "",
      phone: "",
      products: defaultProducts,
    },
  });

  const {
    register,
    handleSubmit,
    formState: { errors, isSubmitting },
    control,
  } = form;
  const nameId = idPrefix ? `${idPrefix}name` : "name";
  const emailId = idPrefix ? `${idPrefix}email` : "email";
  const phoneId = idPrefix ? `${idPrefix}tel` : "tel";

  const onSubmit: SubmitHandler<LeadFormValues> = async (data) => {
    setSubmitError(null);
    try {
      const { id } = await mailApi
        .post("mail", {
          json: { ...data, referer, from: MAIL_REQUEST_FROM },
        })
        .json<{ id: string }>();
      onSuccess(id);
    } catch {
      setSubmitError(t("leadForm.submitError"));
    }
  };

  return (
    <FormProvider {...form}>
      <form
        className={formClassName}
        onSubmit={handleSubmit(onSubmit)}
        noValidate
      >
        {submitError ? (
          <p className="text-sm text-red-400" role="alert">
            {submitError}
          </p>
        ) : null}
        <div className="lg:space-y-[1.111vw] space-y-4">
          <p className="font-medium heading2">{t("leadForm.needTitle")}</p>
          <CheckboxesGroup<LeadFormValues>
            name="products"
            options={projectOptions}
          />
        </div>
        <input
          id={nameId}
          autoComplete="none"
          type="text"
          required
          placeholder={t("leadForm.namePlaceholder")}
          {...register("fullname")}
          className="bg-transparent border-b border-[#37393B] focus:border-white py-4 rounded-none outline-none transition-all w-full placeholder:btnl btnl placeholder:font-medium placeholder:select-none"
        />
        <input
          autoComplete="none"
          required
          id={emailId}
          type="email"
          placeholder={t("leadForm.emailPlaceholder")}
          {...register("email")}
          className="bg-transparent border-b border-[#37393B] focus:border-white py-4 rounded-none btnl outline-none transition-all w-full placeholder:btnl placeholder:font-medium placeholder:select-none"
        />
        <div className="flex gap-x-3 py-2 border-[#3D425C] relative">
          <Controller
            name="phone"
            control={control}
            rules={{
              validate: (value: string) => {
                if (!value?.trim()) return t("leadForm.phoneRequired");
                if (isRuLocale) {
                  return (
                    ruPhoneDigits(value).length === 11 ||
                    t("leadForm.phoneInvalid")
                  );
                }
                const digits = value.replace(/\D/g, "");
                return (
                  (digits.length >= 8 &&
                    digits.length <= INTL_PHONE_MAX_DIGITS) ||
                  t("leadForm.phoneInvalid")
                );
              },
            }}
            render={({ field }) =>
              isRuLocale ? (
                <PhoneInputRu
                  id={phoneId}
                  value={field.value}
                  onChange={field.onChange}
                  onBlur={field.onBlur}
                  inputRef={field.ref}
                  placeholder={
                    phonePlaceholder ?? t("leadForm.phonePlaceholder")
                  }
                />
              ) : (
                <PhoneInputIntl
                  id={phoneId}
                  value={field.value}
                  onChange={field.onChange}
                  onBlur={field.onBlur}
                  inputRef={field.ref}
                  placeholder={
                    phonePlaceholder ?? t("leadForm.phonePlaceholder")
                  }
                />
              )
            }
          />
          <div className="bottom-0 absolute w-full border-b border-[#37393B] peer-focus:border-white -mb-2" />
        </div>
        {errors.phone?.message ? (
          <p className="text-sm text-red-400 -mt-1" role="alert">
            {String(errors.phone.message)}
          </p>
        ) : null}
        <div className="md:flex items-stretch lg:gap-[0.833vw] gap-3 max-md:translate-y-2">
          <Button
            type="submit"
            disabled={isSubmitting}
            className="btnl max-md:mb-3 max-md:w-full lg:px-[2.222vw] lg:py-[1.389vw] px-8 py-5 cursor-pointer lg:rounded-[1.111vw] rounded-2xl disabled:opacity-60"
          >
            {t("leadForm.submit")}
          </Button>
          <div className="text2 xl:max-w-[60%] md:max-lg:max-w-[40%] md:max-lg:py-1">
            <span className="text-[#7A7A7A]">
              {t("leadForm.consentBefore")}
            </span>{" "}
            <a
              target="_blank"
              rel="noopener noreferrer"
              href={t("legalLinks.privacyConsent")}
              className="underline"
            >
              {t("leadForm.consentLinkData")}
            </a>{" "}
            <span className="text-[#7A7A7A]">
              {t("leadForm.consentMiddle")}{" "}
            </span>
            <a
              target="_blank"
              rel="noopener noreferrer"
              href={t("legalLinks.policy")}
              className="underline"
            >
              {t("leadForm.consentLinkPolicy")}
            </a>
          </div>
        </div>
      </form>
    </FormProvider>
  );
}