/*
 This file is part of GNU Taler
 (C) 2021-2023 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/>
 */

/**
 *
 * @author Sebastian Javier Marchano (sebasjm)
 */

import { isRfc3548Base32Charset, randomRfc3548Base32Key } from "@gnu-taler/taler-util";
import { useTranslationContext } from "@gnu-taler/web-util/browser";
import { Fragment, h, VNode } from "preact";
import { useState } from "preact/hooks";
import { AsyncButton } from "../../../../components/exception/AsyncButton.js";
import {
  FormErrors,
  FormProvider,
} from "../../../../components/form/FormProvider.js";
import { Input } from "../../../../components/form/Input.js";
import { InputSelector } from "../../../../components/form/InputSelector.js";
import { InputWithAddon } from "../../../../components/form/InputWithAddon.js";
import { useBackendContext } from "../../../../context/backend.js";
import { MerchantBackend } from "../../../../declaration.js";

type Entity = MerchantBackend.OTP.OtpDeviceAddDetails;

interface Props {
  onCreate: (d: Entity) => Promise<void>;
  onBack?: () => void;
}

const algorithms = [0, 1, 2];
const algorithmsNames = ["off", "30s 8d TOTP-SHA1", "30s 8d eTOTP-SHA1"];

export function CreatePage({ onCreate, onBack }: Props): VNode {
  const { i18n } = useTranslationContext();
  const backend = useBackendContext();

  const [state, setState] = useState<Partial<Entity>>({});

  const [showKey, setShowKey] = useState(false);

  const errors: FormErrors<Entity> = {
    otp_device_id: !state.otp_device_id
      ? i18n.str`required`
      : !/[a-zA-Z0-9]*/.test(state.otp_device_id)
        ? i18n.str`no valid. only characters and numbers`
        : undefined,
    otp_algorithm: !state.otp_algorithm ? i18n.str`required` : undefined,
    otp_key: !state.otp_key
      ? i18n.str`required`
      : !isRfc3548Base32Charset(state.otp_key)
        ? i18n.str`just letters and numbers from 2 to 7`
        : state.otp_key.length !== 32
          ? i18n.str`size of the key should be 32`
          : undefined,
    otp_device_description: !state.otp_device_description
      ? i18n.str`required`
      : !/[a-zA-Z0-9]*/.test(state.otp_device_description)
        ? i18n.str`no valid. only characters and numbers`
        : undefined,
  };

  const hasErrors = Object.keys(errors).some(
    (k) => (errors as any)[k] !== undefined,
  );

  const submitForm = () => {
    if (hasErrors) return Promise.reject();
    return onCreate(state as any);
  };

  return (
    <div>
      <section class="section is-main-section">
        <div class="columns">
          <div class="column" />
          <div class="column is-four-fifths">
            <FormProvider
              object={state}
              valueHandler={setState}
              errors={errors}
            >
              <Input<Entity>
                name="otp_device_id"
                label={i18n.str`ID`}
                tooltip={i18n.str`Internal id on the system`}
              />
              <Input<Entity>
                name="otp_device_description"
                label={i18n.str`Descripiton`}
                tooltip={i18n.str`Useful to identify the device physically`}
              />
              <InputSelector<Entity>
                name="otp_algorithm"
                label={i18n.str`Verification algorithm`}
                tooltip={i18n.str`Algorithm to use to verify transaction in offline mode`}
                values={algorithms}
                toStr={(v) => algorithmsNames[v]}
                fromStr={(v) => Number(v)}
              />
              {state.otp_algorithm && state.otp_algorithm > 0 ? (
                <Fragment>
                  <InputWithAddon<Entity>
                    expand
                    name="otp_key"
                    label={i18n.str`Device key`}
                    inputType={showKey ? "text" : "password"}
                    help="Be sure to be very hard to guess or use the random generator"
                    tooltip={i18n.str`Your device need to have exactly the same value`}
                    fromStr={(v) => v.toUpperCase()}
                    addonAfterAction={() => {
                      setShowKey(!showKey);
                    }}
                    addonAfter={
                      <span class="icon">
                        {showKey ? (
                          <i class="mdi mdi-eye" />
                        ) : (
                          <i class="mdi mdi-eye-off" />
                        )}
                      </span>
                    }
                    side={
                      <button
                        data-tooltip={i18n.str`generate random secret key`}
                        class="button is-info mr-3"
                        onClick={(e) => {
                          setState((s) => ({
                            ...s,
                            otp_key: randomRfc3548Base32Key(),
                          }));
                        }}
                      >
                        <i18n.Translate>random</i18n.Translate>
                      </button>
                    }
                  />
                </Fragment>
              ) : undefined}
            </FormProvider>

            <div class="buttons is-right mt-5">
              {onBack && (
                <button class="button" onClick={onBack}>
                  <i18n.Translate>Cancel</i18n.Translate>
                </button>
              )}
              <AsyncButton
                disabled={hasErrors}
                data-tooltip={
                  hasErrors
                    ? i18n.str`Need to complete marked fields`
                    : "confirm operation"
                }
                onClick={submitForm}
              >
                <i18n.Translate>Confirm</i18n.Translate>
              </AsyncButton>
            </div>
          </div>
          <div class="column" />
        </div>
      </section>
    </div>
  );
}
