/*
 This file is part of GNU Taler
 (C) 2021-2024 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 {
  AmountString,
  Amounts,
  Duration,
  TalerError,
  TalerMerchantApi,
  TranslatedString,
} from "@gnu-taler/taler-util";
import {
  useTranslationContext
} from "@gnu-taler/web-util/browser";
import { Fragment, VNode, h } 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 { InputCurrency } from "../../../../components/form/InputCurrency.js";
import { InputDuration } from "../../../../components/form/InputDuration.js";
import { InputNumber } from "../../../../components/form/InputNumber.js";
import { InputSelector } from "../../../../components/form/InputSelector.js";
import { InputToggle } from "../../../../components/form/InputToggle.js";
import { TextField } from "../../../../components/form/TextField.js";
import { useSessionContext } from "../../../../context/session.js";
import { useInstanceOtpDevices } from "../../../../hooks/otp.js";

type Entity = {
  description?: string;
  otpId?: string | null;
  summary?: string;
  amount?: AmountString;
  minimum_age?: number;
  pay_duration?: Duration;
  summary_editable?: boolean;
  amount_editable?: boolean;
  currency_editable?: boolean;
};

interface Props {
  onUpdate: (d: TalerMerchantApi.TemplatePatchDetails) => Promise<void>;
  onBack?: () => void;
  template: TalerMerchantApi.TemplateDetails & WithId;
}

export function UpdatePage({ template, onUpdate, onBack }: Props): VNode {
  const { i18n } = useTranslationContext();
  const { config } = useSessionContext();
  const {state:session} = useSessionContext();

  const [state, setState] = useState<Partial<Entity>>({
    description: template.template_description,
    minimum_age: template.template_contract.minimum_age,
    otpId: template.otp_id,
    pay_duration: template.template_contract.pay_duration
      ? Duration.fromTalerProtocolDuration(
          template.template_contract.pay_duration,
        )
      : undefined,
    summary:
      template.editable_defaults?.summary ?? template.template_contract.summary,
    amount:
      template.editable_defaults?.amount ??
      (template.template_contract.amount as AmountString | undefined),
    currency_editable: !!template.editable_defaults?.currency,
    summary_editable: !!template.editable_defaults?.summary,
    amount_editable: !!template.editable_defaults?.amount,
  });

  function updateState(up: (s: Partial<Entity>) => Partial<Entity>) {
    setState((old) => {
      const newState = up(old);
      if (!newState.amount_editable) {
        newState.currency_editable = false;
      }
      return newState;
    });
  }

  const devices = useInstanceOtpDevices();
  const deviceList =
    !devices || devices instanceof TalerError || devices.type === "fail"
      ? []
      : devices.body.otp_devices;
  const deviceMap = deviceList.reduce(
    (prev, cur) => {
      prev[cur.otp_device_id] = cur.device_description as TranslatedString;
      return prev;
    },
    {} as Record<string, TranslatedString>,
  );

  const parsedPrice = !state.amount ? undefined : Amounts.parse(state.amount);

  const errors: FormErrors<Entity> = {
    description: !state.description ? i18n.str`should not be empty` : undefined,
    amount: !state.amount
      ? undefined
      : !parsedPrice
        ? i18n.str`not valid`
        : Amounts.isZero(parsedPrice)
          ? i18n.str`must be greater than 0`
          : undefined,
    minimum_age:
      state.minimum_age && state.minimum_age < 0
        ? i18n.str`should be greater that 0`
        : undefined,
    pay_duration: !state.pay_duration
      ? i18n.str`can't be empty`
      : state.pay_duration.d_ms === "forever"
        ? undefined
        : state.pay_duration.d_ms < 1000 // less than one second
          ? i18n.str`to short`
          : undefined,
  };

  const cList = Object.values(config.currencies).map((d) => d.name);

  const hasErrors = Object.keys(errors).some(
    (k) => (errors as Record<string, unknown>)[k] !== undefined,
  );

  const submitForm = () => {
    if (hasErrors) return Promise.reject();
    return onUpdate({
      template_description: state.description!,
      template_contract: {
        minimum_age: state.minimum_age!,
        pay_duration: Duration.toTalerProtocolDuration(state.pay_duration!),
        amount: state.amount_editable ? undefined : state.amount,
        summary: state.summary_editable ? undefined : state.summary,
        currency:
          cList.length > 1 && state.currency_editable
            ? undefined
            : config.currency,
      },
      editable_defaults: {
        amount: !state.amount_editable ? undefined : state.amount,
        summary: !state.summary_editable ? undefined : state.summary,
        currency:
          cList.length === 1 || !state.currency_editable
            ? undefined
            : config.currency,
      },
      otp_id: state.otpId!,
    });
  };

  return (
    <div>
      <section class="section">
        <section class="hero is-hero-bar">
          <div class="hero-body">
            <div class="level">
              <div class="level-left">
                <div class="level-item">
                  <span class="is-size-4">
                    {new URL(`templates/${template.id}`, session.backendUrl.href).href}
                  </span>
                </div>
              </div>
            </div>
          </div>
        </section>
        <hr />

        <section class="section is-main-section">
          <div class="columns">
            <div class="column is-four-fifths">
              <FormProvider
                object={state}
                valueHandler={updateState}
                errors={errors}
              >
                <Input<Entity>
                  name="description"
                  label={i18n.str`Description`}
                  help=""
                  tooltip={i18n.str`Describe what this template stands for`}
                />
                <Input<Entity>
                  name="summary"
                  inputType="multiline"
                  label={i18n.str`Summary`}
                  tooltip={i18n.str`If specified, this template will create order with the same summary`}
                />
                <InputToggle<Entity>
                  name="summary_editable"
                  label={i18n.str`Summary is editable`}
                  tooltip={i18n.str`Allow the user to change the summary.`}
                />
                <InputCurrency<Entity>
                  name="amount"
                  label={i18n.str`Amount`}
                  tooltip={i18n.str`If specified, this template will create order with the same price`}
                />
                <InputToggle<Entity>
                  name="amount_editable"
                  label={i18n.str`Amount is editable`}
                  tooltip={i18n.str`Allow the user to select the amount to pay.`}
                />
                {cList.length > 1 && (
                  <Fragment>
                    <InputToggle<Entity>
                      name="currency_editable"
                      readonly={!state.amount_editable}
                      label={i18n.str`Currency is editable`}
                      tooltip={i18n.str`Allow the user to change currency.`}
                    />
                    <TextField name="sc" label={i18n.str`Supported currencies`}>
                      <i18n.Translate>
                        supported currencies: {cList.join(", ")}
                      </i18n.Translate>
                    </TextField>
                  </Fragment>
                )}
                <InputNumber<Entity>
                  name="minimum_age"
                  label={i18n.str`Minimum age`}
                  help=""
                  tooltip={i18n.str`Is this contract restricted to some age?`}
                />
                <InputDuration<Entity>
                  name="pay_duration"
                  label={i18n.str`Payment timeout`}
                  help=""
                  tooltip={i18n.str`How much time has the customer to complete the payment once the order was created.`}
                />
                {!deviceList.length ? (
                  <TextField
                    name="otpId"
                    label={i18n.str`OTP device`}
                    tooltip={i18n.str`Use to verify transaction while offline.`}
                  >
                    <i18n.Translate>No OTP device.</i18n.Translate>&nbsp;
                    <a href="/otp-devices/new">
                      <i18n.Translate>Add one first</i18n.Translate>
                    </a>
                  </TextField>
                ) : (
                  <InputSelector<Entity>
                    name="otpId"
                    label={i18n.str`OTP device`}
                    values={[
                      undefined,
                      ...deviceList.map((e) => e.otp_device_id),
                    ]}
                    toStr={(v?: string) => {
                      if (!v) {
                        return i18n.str`No device`;
                      }
                      return deviceMap[v];
                    }}
                    tooltip={i18n.str`Use to verify transaction in offline mode.`}
                  />
                )}
              </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>
        </section>
      </section>
    </div>
  );
}