/*
 This file is part of GNU Taler
 (C) 2022 Taler Systems S.A.

 GNU Taler is free software; you can redistribute it and/or modify it under the
 terms of the GNU General Public License as published by the Free Software
 Foundation; either version 3, or (at your option) any later version.

 GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

 You should have received a copy of the GNU General Public License along with
 GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */

/* eslint-disable react-hooks/rules-of-hooks */
import { Amounts, TalerProtocolTimestamp } from "@gnu-taler/taler-util";
import { WalletApiOperation } from "@gnu-taler/taler-wallet-core";
import { isFuture, parse } from "date-fns";
import { useState } from "preact/hooks";
import { alertFromError, useAlertContext } from "../../context/alert.js";
import { useBackendContext } from "../../context/backend.js";
import { useTranslationContext } from "@gnu-taler/web-util/browser";
import { useAsyncAsHook } from "../../hooks/useAsyncAsHook.js";
import { useSelectedExchange } from "../../hooks/useSelectedExchange.js";
import { RecursiveState } from "../../utils/index.js";
import { Props, State } from "./index.js";

export function useComponentState({
  amount: amountStr,
  onClose,
  onSuccess,
}: Props): RecursiveState<State> {
  const amount = Amounts.parseOrThrow(amountStr);
  const api = useBackendContext();

  const hook = useAsyncAsHook(() =>
    api.wallet.call(WalletApiOperation.ListExchanges, {}),
  );
  const { i18n } = useTranslationContext();

  if (!hook) {
    return {
      status: "loading",
      error: undefined,
    };
  }
  if (hook.hasError) {
    return {
      status: "error",
      error: alertFromError(
        i18n.str`Could not load the status of the term of service`,
        hook,
      ),
    };
  }
  // if (hook.hasError) {
  //   return {
  //     status: "loading-uri",
  //     error: hook,
  //   };
  // }

  const exchangeList = hook.response.exchanges;

  return () => {
    const [subject, setSubject] = useState<string | undefined>();
    const [timestamp, setTimestamp] = useState<string | undefined>();
    const { pushAlertOnError } = useAlertContext();

    const selectedExchange = useSelectedExchange({
      currency: amount.currency,
      defaultExchange: undefined,
      list: exchangeList,
    });

    if (selectedExchange.status !== "ready") {
      return selectedExchange;
    }

    const exchange = selectedExchange.selected;

    const hook = useAsyncAsHook(async () => {
      const resp = await api.wallet.call(
        WalletApiOperation.CheckPeerPullCredit,
        {
          amount: amountStr,
          exchangeBaseUrl: exchange.exchangeBaseUrl,
        },
      );
      return resp;
    });

    if (!hook) {
      return {
        status: "loading",
        error: undefined,
      };
    }

    if (hook.hasError) {
      return {
        status: "error",
        error: alertFromError(
          i18n.str`Could not load the status of the term of service`,
          hook,
        ),
      };
      // return {
      //   status: "loading-uri",
      //   error: hook,
      // };
    }

    const { amountEffective, amountRaw } = hook.response;
    const requestAmount = Amounts.parseOrThrow(amountRaw);
    const toBeReceived = Amounts.parseOrThrow(amountEffective);

    let purse_expiration: TalerProtocolTimestamp | undefined = undefined;
    let timestampError: string | undefined = undefined;

    const t =
      timestamp === undefined
        ? undefined
        : parse(timestamp, "dd/MM/yyyy", new Date());

    if (t !== undefined) {
      if (Number.isNaN(t.getTime())) {
        timestampError = 'Should have the format "dd/MM/yyyy"';
      } else {
        if (!isFuture(t)) {
          timestampError = "Should be in the future";
        } else {
          purse_expiration = {
            t_s: t.getTime() / 1000,
          };
        }
      }
    }

    async function accept(): Promise<void> {
      if (!subject || !purse_expiration) return;

      const resp = await api.wallet.call(
        WalletApiOperation.InitiatePeerPullCredit,
        {
          exchangeBaseUrl: exchange.exchangeBaseUrl,
          partialContractTerms: {
            amount: Amounts.stringify(amount),
            summary: subject,
            purse_expiration,
          },
        },
      );

      onSuccess(resp.transactionId);
    }
    const unableToCreate =
      !subject || Amounts.isZero(amount) || !purse_expiration;

    return {
      status: "ready",
      subject: {
        error:
          subject === undefined
            ? undefined
            : !subject
            ? "Can't be empty"
            : undefined,
        value: subject ?? "",
        onInput: pushAlertOnError(async (e) => setSubject(e)),
      },
      expiration: {
        error: timestampError,
        value: timestamp === undefined ? "" : timestamp,
        onInput: pushAlertOnError(async (e) => {
          setTimestamp(e);
        }),
      },
      doSelectExchange: selectedExchange.doSelect,
      exchangeUrl: exchange.exchangeBaseUrl,
      create: {
        onClick: unableToCreate ? undefined : pushAlertOnError(accept),
      },
      cancel: {
        onClick: pushAlertOnError(onClose),
      },
      requestAmount,
      toBeReceived,
      error: undefined,
    };
  };
}