"use client";

import { useImperativeHandle, forwardRef, useState, type ReactNode } from "react";
import {
  FLOCK_CHECKOUT_FIELD_HINTS,
  FLOCK_CHECKOUT_HOURS,
  FLOCK_CHECKOUT_ROLE_OPTIONS,
  emptyFlockCheckoutDetailsDraft,
  flockDetailsHasErrors,
  toFlockCheckoutApiDetails,
  validateFlockCheckoutDetailsDraft,
  type FlockCheckoutDetailsDraft,
  type FlockCheckoutLocationDraft,
  type FlockCheckoutRole,
  type FlockDetailsFieldErrors,
} from "@/lib/flock/flock-checkout-details-rules";
import { ErrorBanner } from "@/components/ui/error-banner";

export type FlockLoggedInDetailsFormHandle = {
  validateAndGetDetails: () => ReturnType<
    typeof toFlockCheckoutApiDetails
  > | null;
};

type Props = {
  disabled?: boolean;
  pickupZip?: string;
  deliveryZip?: string;
  /** 首价货件摘要（只读），对齐官网 Shipment details 货件行 */
  shipmentSummary?: string;
};

const inputCls =
  "w-full rounded-md border border-border bg-surface px-3 py-2 text-sm text-text-primary outline-none focus:border-primary disabled:opacity-60";
const inputErrCls =
  "w-full rounded-md border border-error bg-surface px-3 py-2 text-sm text-text-primary outline-none focus:border-error disabled:opacity-60";

function Field({
  label,
  required,
  error,
  hint,
  children,
}: {
  label: string;
  required?: boolean;
  error?: string;
  hint?: string;
  children: ReactNode;
}) {
  return (
    <label className="block space-y-1">
      <span className="text-xs font-medium text-text-secondary">
        {label}
        {required ? <span className="text-error"> *</span> : null}
      </span>
      {children}
      {error ? <p className="text-[11px] text-error">{error}</p> : null}
      {!error && hint ? (
        <p className="text-[11px] text-text-disabled">{hint}</p>
      ) : null}
    </label>
  );
}

function LocationAddressFields({
  side,
  loc,
  errors,
  disabled,
  addressLocked,
  onPatch,
}: {
  side: "pickup" | "delivery";
  loc: FlockCheckoutLocationDraft;
  errors?: Partial<Record<keyof FlockCheckoutLocationDraft, string>>;
  disabled?: boolean;
  addressLocked: boolean;
  onPatch: (patch: Partial<FlockCheckoutLocationDraft>) => void;
}) {
  const locked = Boolean(disabled || addressLocked);
  return (
    <>
      <Field
        label="地址 1"
        required={!addressLocked}
        error={errors?.address1}
        hint={
          addressLocked
            ? FLOCK_CHECKOUT_FIELD_HINTS.useBilling
            : FLOCK_CHECKOUT_FIELD_HINTS.addressMismatch
        }
      >
        <input
          disabled={locked}
          className={errors?.address1 ? inputErrCls : inputCls}
          value={loc.address1}
          onChange={(e) => onPatch({ address1: e.target.value })}
        />
      </Field>
      <Field label="地址 2">
        <input
          disabled={locked}
          className={inputCls}
          value={loc.address2}
          onChange={(e) => onPatch({ address2: e.target.value })}
        />
      </Field>
      <Field label="城市" required={!addressLocked} error={errors?.city}>
        <input
          disabled={locked}
          className={errors?.city ? inputErrCls : inputCls}
          value={loc.city}
          onChange={(e) => onPatch({ city: e.target.value })}
        />
      </Field>
      <Field label="州" required={!addressLocked} error={errors?.state}>
        <input
          disabled={locked}
          className={errors?.state ? inputErrCls : inputCls}
          value={loc.state}
          onChange={(e) => onPatch({ state: e.target.value })}
        />
      </Field>
      <Field label="邮编" required={!addressLocked} error={errors?.zip}>
        <input
          disabled={locked}
          className={errors?.zip ? inputErrCls : inputCls}
          value={loc.zip}
          onChange={(e) => onPatch({ zip: e.target.value })}
        />
      </Field>
    </>
  );
}

/** 二级结账详情：对齐官网 Pickup / Delivery / Shipment details */
export const FlockLoggedInDetailsForm = forwardRef<
  FlockLoggedInDetailsFormHandle,
  Props
>(function FlockLoggedInDetailsForm(
  {
    disabled = false,
    pickupZip = "",
    deliveryZip = "",
    shipmentSummary = "",
  },
  ref,
) {
  const [draft, setDraft] = useState<FlockCheckoutDetailsDraft>(() =>
    emptyFlockCheckoutDetailsDraft({ pickupZip, deliveryZip }),
  );
  const [errors, setErrors] = useState<FlockDetailsFieldErrors>({});
  const [formError, setFormError] = useState<string | null>(null);

  useImperativeHandle(ref, () => ({
    validateAndGetDetails: () => {
      const next = validateFlockCheckoutDetailsDraft(draft);
      setErrors(next);
      if (flockDetailsHasErrors(next)) {
        setFormError("请先修正结账详情中的必填项与格式错误");
        return null;
      }
      setFormError(null);
      return toFlockCheckoutApiDetails(draft);
    },
  }));

  const setRole = (role: FlockCheckoutRole) => {
    setDraft((d) => ({ ...d, role }));
    setErrors((e) => ({ ...e, role: undefined }));
  };

  const patchPickup = (patch: Partial<FlockCheckoutLocationDraft>) => {
    setDraft((d) => ({ ...d, pickup: { ...d.pickup, ...patch } }));
  };

  const patchDelivery = (patch: Partial<FlockCheckoutLocationDraft>) => {
    setDraft((d) => ({ ...d, delivery: { ...d.delivery, ...patch } }));
  };

  return (
    <div className="space-y-5">
      <div>
        <h2 className="text-lg font-semibold text-text-primary">结账详情</h2>
        <p className="mt-1 text-xs text-text-secondary">
          {FLOCK_CHECKOUT_FIELD_HINTS.review}
        </p>
      </div>

      {formError ? <ErrorBanner>{formError}</ErrorBanner> : null}

      <section className="space-y-3 rounded-lg border border-border bg-surface p-4">
        <h3 className="text-sm font-semibold text-text-primary">您的角色</h3>
        <div className="flex flex-wrap gap-2">
          {FLOCK_CHECKOUT_ROLE_OPTIONS.map((opt) => (
            <button
              key={opt.id}
              type="button"
              disabled={disabled}
              onClick={() => setRole(opt.id)}
              className={
                "rounded-md border px-3 py-1.5 text-sm " +
                (draft.role === opt.id
                  ? "border-primary bg-primary/10 font-medium text-primary"
                  : "border-border text-text-secondary hover:border-primary/40")
              }
            >
              {opt.label}
            </button>
          ))}
        </div>
        {errors.role ? (
          <p className="text-[11px] text-error">{errors.role}</p>
        ) : null}
      </section>

      <section className="space-y-3 rounded-lg border border-border bg-surface p-4">
        <div className="flex flex-wrap items-center justify-between gap-2">
          <h3 className="text-sm font-semibold text-text-primary">提货地点</h3>
          <label className="flex items-center gap-2 text-xs text-text-secondary">
            <input
              type="checkbox"
              disabled={disabled}
              checked={draft.use_billing_for_pickup}
              onChange={(e) =>
                setDraft((d) => ({
                  ...d,
                  use_billing_for_pickup: e.target.checked,
                }))
              }
            />
            使用账单地址
          </label>
        </div>
        <p className="text-[11px] text-text-disabled">
          {FLOCK_CHECKOUT_FIELD_HINTS.useBilling}
        </p>
        <div className="grid gap-3 md:grid-cols-2">
          <Field
            label="公司名称"
            required
            error={errors.pickup?.company_name}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.addressSync}
          >
            <input
              disabled={disabled}
              className={
                errors.pickup?.company_name ? inputErrCls : inputCls
              }
              value={draft.pickup.company_name}
              onChange={(e) => patchPickup({ company_name: e.target.value })}
            />
          </Field>
          <LocationAddressFields
            side="pickup"
            loc={draft.pickup}
            errors={errors.pickup}
            disabled={disabled}
            addressLocked={draft.use_billing_for_pickup}
            onPatch={patchPickup}
          />
          <Field
            label="联系人"
            required
            error={errors.pickup?.contact_name}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.contactHelper}
          >
            <input
              disabled={disabled}
              className={
                errors.pickup?.contact_name ? inputErrCls : inputCls
              }
              value={draft.pickup.contact_name}
              onChange={(e) => patchPickup({ contact_name: e.target.value })}
            />
          </Field>
          <Field
            label="电话"
            required
            error={errors.pickup?.contact_phone}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.phone}
          >
            <input
              disabled={disabled}
              className={
                errors.pickup?.contact_phone ? inputErrCls : inputCls
              }
              value={draft.pickup.contact_phone}
              onChange={(e) => patchPickup({ contact_phone: e.target.value })}
              placeholder="(626) 595-1180"
            />
          </Field>
          <Field
            label="邮箱"
            required
            error={errors.pickup?.contact_email}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.email}
          >
            <input
              disabled={disabled}
              className={
                errors.pickup?.contact_email ? inputErrCls : inputCls
              }
              value={draft.pickup.contact_email}
              onChange={(e) => patchPickup({ contact_email: e.target.value })}
            />
          </Field>
          <Field
            label="开门时间"
            required
            error={errors.pickup?.opens_at}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.hours}
          >
            <select
              disabled={disabled}
              className={errors.pickup?.opens_at ? inputErrCls : inputCls}
              value={draft.pickup.opens_at}
              onChange={(e) => patchPickup({ opens_at: e.target.value })}
            >
              {FLOCK_CHECKOUT_HOURS.map((h) => (
                <option key={h} value={h}>
                  {h}
                </option>
              ))}
            </select>
          </Field>
          <Field label="关门时间" required error={errors.pickup?.closes_at}>
            <select
              disabled={disabled}
              className={errors.pickup?.closes_at ? inputErrCls : inputCls}
              value={draft.pickup.closes_at}
              onChange={(e) => patchPickup({ closes_at: e.target.value })}
            >
              {FLOCK_CHECKOUT_HOURS.map((h) => (
                <option key={h} value={h}>
                  {h}
                </option>
              ))}
            </select>
          </Field>
        </div>
      </section>

      <section className="space-y-3 rounded-lg border border-border bg-surface p-4">
        <div className="flex flex-wrap items-center justify-between gap-2">
          <h3 className="text-sm font-semibold text-text-primary">派送地点</h3>
          <label className="flex items-center gap-2 text-xs text-text-secondary">
            <input
              type="checkbox"
              disabled={disabled}
              checked={draft.use_billing_for_delivery}
              onChange={(e) =>
                setDraft((d) => ({
                  ...d,
                  use_billing_for_delivery: e.target.checked,
                }))
              }
            />
            使用账单地址
          </label>
        </div>
        <p className="text-[11px] text-text-disabled">
          {FLOCK_CHECKOUT_FIELD_HINTS.useBilling}
        </p>
        <div className="grid gap-3 md:grid-cols-2">
          <Field
            label="公司名称"
            required
            error={errors.delivery?.company_name}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.addressSync}
          >
            <input
              disabled={disabled}
              className={
                errors.delivery?.company_name ? inputErrCls : inputCls
              }
              value={draft.delivery.company_name}
              onChange={(e) =>
                patchDelivery({ company_name: e.target.value })
              }
            />
          </Field>
          <LocationAddressFields
            side="delivery"
            loc={draft.delivery}
            errors={errors.delivery}
            disabled={disabled}
            addressLocked={draft.use_billing_for_delivery}
            onPatch={patchDelivery}
          />
          <Field
            label="联系人"
            required
            error={errors.delivery?.contact_name}
          >
            <input
              disabled={disabled}
              className={
                errors.delivery?.contact_name ? inputErrCls : inputCls
              }
              value={draft.delivery.contact_name}
              onChange={(e) =>
                patchDelivery({ contact_name: e.target.value })
              }
            />
          </Field>
          <Field
            label="电话"
            required
            error={errors.delivery?.contact_phone}
            hint={FLOCK_CHECKOUT_FIELD_HINTS.phone}
          >
            <input
              disabled={disabled}
              className={
                errors.delivery?.contact_phone ? inputErrCls : inputCls
              }
              value={draft.delivery.contact_phone}
              onChange={(e) =>
                patchDelivery({ contact_phone: e.target.value })
              }
              placeholder="(415) 621-8840"
            />
          </Field>
          <Field
            label="邮箱"
            required
            error={errors.delivery?.contact_email}
          >
            <input
              disabled={disabled}
              className={
                errors.delivery?.contact_email ? inputErrCls : inputCls
              }
              value={draft.delivery.contact_email}
              onChange={(e) =>
                patchDelivery({ contact_email: e.target.value })
              }
            />
          </Field>
          <Field label="开门时间" required error={errors.delivery?.opens_at}>
            <select
              disabled={disabled}
              className={
                errors.delivery?.opens_at ? inputErrCls : inputCls
              }
              value={draft.delivery.opens_at}
              onChange={(e) => patchDelivery({ opens_at: e.target.value })}
            >
              {FLOCK_CHECKOUT_HOURS.map((h) => (
                <option key={h} value={h}>
                  {h}
                </option>
              ))}
            </select>
          </Field>
          <Field
            label="关门时间"
            required
            error={errors.delivery?.closes_at}
          >
            <select
              disabled={disabled}
              className={
                errors.delivery?.closes_at ? inputErrCls : inputCls
              }
              value={draft.delivery.closes_at}
              onChange={(e) => patchDelivery({ closes_at: e.target.value })}
            >
              {FLOCK_CHECKOUT_HOURS.map((h) => (
                <option key={h} value={h}>
                  {h}
                </option>
              ))}
            </select>
          </Field>
        </div>
        <div className="space-y-2">
          <p className="text-xs font-medium text-text-secondary">
            该地点是否允许周末派送？
          </p>
          <div className="flex gap-2">
            {([true, false] as const).map((yes) => (
              <button
                key={String(yes)}
                type="button"
                disabled={disabled}
                onClick={() => patchDelivery({ weekend_delivery: yes })}
                className={
                  "rounded-md border px-3 py-1.5 text-sm " +
                  (draft.delivery.weekend_delivery === yes
                    ? "border-primary bg-primary/10 font-medium text-primary"
                    : "border-border text-text-secondary")
                }
              >
                {yes ? "是" : "否"}
              </button>
            ))}
          </div>
          <p className="text-[11px] text-text-disabled">
            {FLOCK_CHECKOUT_FIELD_HINTS.weekend}
          </p>
        </div>
      </section>

      <section className="space-y-3 rounded-lg border border-border bg-surface p-4">
        <h3 className="text-sm font-semibold text-text-primary">运输详情</h3>
        {shipmentSummary ? (
          <div className="rounded-md border border-border bg-bg px-3 py-2 text-sm text-text-primary">
            <p className="text-xs font-medium text-text-secondary">货件摘要</p>
            <p className="mt-1">{shipmentSummary}</p>
            <p className="mt-1 text-[11px] text-text-disabled">
              {FLOCK_CHECKOUT_FIELD_HINTS.shipmentItems}
            </p>
          </div>
        ) : null}
        <div className="grid gap-3 md:grid-cols-2">
          <Field label="NMFC" hint={FLOCK_CHECKOUT_FIELD_HINTS.nmfc}>
            <input
              disabled={disabled}
              className={inputCls}
              value={draft.nmfc}
              onChange={(e) =>
                setDraft((d) => ({ ...d, nmfc: e.target.value }))
              }
              placeholder="如 100240-01"
            />
          </Field>
          <Field label="PO 单号" hint={FLOCK_CHECKOUT_FIELD_HINTS.po}>
            <input
              disabled={disabled}
              className={inputCls}
              value={draft.po_number}
              onChange={(e) =>
                setDraft((d) => ({ ...d, po_number: e.target.value }))
              }
            />
          </Field>
        </div>
        <Field
          label="宣示声明"
          hint={FLOCK_CHECKOUT_FIELD_HINTS.declaration}
        >
          <textarea
            disabled={disabled}
            rows={2}
            className={inputCls}
            value={draft.declaration_statement}
            onChange={(e) =>
              setDraft((d) => ({
                ...d,
                declaration_statement: e.target.value,
              }))
            }
            placeholder="联系人确认、特殊要求等"
          />
        </Field>
        <Field label="BOL 备注" hint={FLOCK_CHECKOUT_FIELD_HINTS.bol}>
          <input
            disabled={disabled}
            className={inputCls}
            value={draft.bol_remarks}
            onChange={(e) =>
              setDraft((d) => ({ ...d, bol_remarks: e.target.value }))
            }
          />
        </Field>
        <Field label="Flock 备注" hint={FLOCK_CHECKOUT_FIELD_HINTS.notes}>
          <textarea
            disabled={disabled}
            rows={3}
            className={inputCls}
            value={draft.notes}
            onChange={(e) =>
              setDraft((d) => ({ ...d, notes: e.target.value }))
            }
          />
        </Field>
        <label className="flex items-start gap-2 text-sm text-text-primary">
          <input
            type="checkbox"
            disabled={disabled}
            className="mt-0.5"
            checked={draft.documentation_required}
            onChange={(e) =>
              setDraft((d) => ({
                ...d,
                documentation_required: e.target.checked,
              }))
            }
          />
          <span>
            提货需要单据
            <span className="mt-0.5 block text-[11px] text-text-disabled">
              {FLOCK_CHECKOUT_FIELD_HINTS.documentation}
            </span>
          </span>
        </label>
      </section>
    </div>
  );
});