import {
  ActionGroup,
  AlertVariant,
  Button,
  Checkbox,
  FormGroup,
  PageSection,
  Switch,
  TextInput,
} from "@patternfly/react-core";
import type RealmRepresentation from "@keycloak/keycloak-admin-client/lib/defs/realmRepresentation";
import React, { useState } from "react";
import { Controller, useForm, useWatch } from "react-hook-form";
import { useTranslation } from "react-i18next";
import { useAlerts } from "../components/alert/Alerts";
import { FormAccess } from "../components/form-access/FormAccess";
import { HelpItem } from "../components/help-enabler/HelpItem";
import { FormPanel } from "../components/scroll-form/FormPanel";
import { useAdminClient } from "../context/auth/AdminClient";
import { useRealm } from "../context/realm-context/RealmContext";
import { useWhoAmI } from "../context/whoami/WhoAmI";
import { emailRegexPattern } from "../util";
import { AddUserEmailModal } from "./AddUserEmailModal";
import "./realm-settings-section.css";

type RealmSettingsEmailTabProps = {
  realm: RealmRepresentation;
};

export type EmailRegistrationCallback = (registered: boolean) => void;

export const RealmSettingsEmailTab = ({
  realm: initialRealm,
}: RealmSettingsEmailTabProps) => {
  const { t } = useTranslation("realm-settings");
  const adminClient = useAdminClient();
  const { realm: realmName } = useRealm();
  const { addAlert, addError } = useAlerts();
  const { whoAmI } = useWhoAmI();

  const [realm, setRealm] = useState(initialRealm);
  const [callback, setCallback] = useState<EmailRegistrationCallback>();
  const {
    register,
    control,
    handleSubmit,
    errors,
    watch,
    reset: resetForm,
    getValues,
  } = useForm<RealmRepresentation>({ defaultValues: realm });

  const reset = () => resetForm(realm);
  const watchFromValue = watch("smtpServer.from", "");
  const watchHostValue = watch("smtpServer.host", "");

  const authenticationEnabled = useWatch({
    control,
    name: "smtpServer.authentication",
    defaultValue: "",
  });

  const save = async (form: RealmRepresentation) => {
    try {
      const registered = await registerEmailIfNeeded();

      if (!registered) {
        return;
      }

      const savedRealm = { ...realm, ...form };
      await adminClient.realms.update({ realm: realmName }, savedRealm);
      setRealm(savedRealm);
      addAlert(t("saveSuccess"), AlertVariant.success);
    } catch (error) {
      addError("realm-settings:saveError", error);
    }
  };

  const testConnection = async () => {
    const serverSettings = { ...getValues()["smtpServer"] };

    // Code below uses defensive coding as the server configuration uses an ambiguous record type.
    if (typeof serverSettings.port === "string") {
      serverSettings.port = Number(serverSettings.port);
    }

    if (typeof serverSettings.ssl === "string") {
      serverSettings.ssl = serverSettings.ssl === true.toString();
    }

    if (typeof serverSettings.starttls === "string") {
      serverSettings.starttls = serverSettings.starttls === true.toString();
    }

    // For some reason the API wants a duplicate field for the authentication status.
    // Somebody thought this was a good idea, so here we are.
    if (serverSettings.authentication === true.toString()) {
      serverSettings.auth = true;
    }

    try {
      const registered = await registerEmailIfNeeded();

      if (!registered) {
        return;
      }

      await adminClient.realms.testSMTPConnection(
        { realm: realm.realm! },
        serverSettings
      );
      addAlert(t("testConnectionSuccess"), AlertVariant.success);
    } catch (error) {
      addError("realm-settings:testConnectionError", error);
    }
  };

  /**
   * Triggers the flow to register the user's email if the user does not yet have one configured, if successful resolves true, otherwise false.
   */
  const registerEmailIfNeeded = async () => {
    const user = await adminClient.users.findOne({ id: whoAmI.getUserId() });

    // A user should always be found, throw if it is not.
    if (!user) {
      throw new Error("Unable to find user.");
    }

    // User already has an e-mail associated with it, no need to register.
    if (user.email) {
      return true;
    }

    // User needs to register, show modal to do so.
    return new Promise<boolean>((resolve) => {
      const callback: EmailRegistrationCallback = (registered) => {
        setCallback(undefined);
        resolve(registered);
      };

      setCallback(() => callback);
    });
  };

  return (
    <>
      {callback && <AddUserEmailModal callback={callback} />}
      <PageSection variant="light">
        <FormPanel title={t("template")} className="kc-email-template">
          <FormAccess
            isHorizontal
            role="manage-realm"
            className="pf-u-mt-lg"
            onSubmit={handleSubmit(save)}
          >
            <FormGroup
              label={t("from")}
              fieldId="kc-display-name"
              isRequired
              validated={errors.smtpServer?.from ? "error" : "default"}
              helperTextInvalid={t("users:emailInvalid")}
            >
              <TextInput
                type="email"
                id="kc-sender-email-address"
                data-testid="sender-email-address"
                name="smtpServer.from"
                ref={register({
                  pattern: emailRegexPattern,
                  required: true,
                })}
                placeholder="Sender email address"
                validated={errors.smtpServer?.from ? "error" : "default"}
              />
            </FormGroup>
            <FormGroup
              label={t("fromDisplayName")}
              fieldId="kc-from-display-name"
              labelIcon={
                <HelpItem
                  helpText="realm-settings-help:fromDisplayName"
                  fieldLabelId="realm-settings:authentication"
                />
              }
            >
              <TextInput
                type="text"
                id="kc-from-display-name"
                data-testid="from-display-name"
                name="smtpServer.fromDisplayName"
                ref={register}
                placeholder="Display name for Sender email address"
              />
            </FormGroup>
            <FormGroup
              label={t("replyTo")}
              fieldId="kc-reply-to"
              validated={errors.smtpServer?.replyTo ? "error" : "default"}
              helperTextInvalid={t("users:emailInvalid")}
            >
              <TextInput
                type="email"
                id="kc-reply-to"
                name="smtpServer.replyTo"
                ref={register({
                  pattern: emailRegexPattern,
                })}
                placeholder="Reply to email address"
                validated={errors.smtpServer?.replyTo ? "error" : "default"}
              />
            </FormGroup>
            <FormGroup
              label={t("replyToDisplayName")}
              fieldId="kc-reply-to-display-name"
              labelIcon={
                <HelpItem
                  helpText="realm-settings-help:replyToDisplayName"
                  fieldLabelId="realm-settings:replyToDisplayName"
                />
              }
            >
              <TextInput
                type="text"
                id="kc-reply-to-display-name"
                name="smtpServer.replyToDisplayName"
                ref={register}
                placeholder='Display name for "reply to" email address'
              />
            </FormGroup>
            <FormGroup
              label={t("envelopeFrom")}
              fieldId="kc-envelope-from"
              labelIcon={
                <HelpItem
                  helpText="realm-settings-help:envelopeFrom"
                  fieldLabelId="realm-settings:envelopeFrom"
                />
              }
            >
              <TextInput
                type="text"
                id="kc-envelope-from"
                name="smtpServer.envelopeFrom"
                ref={register}
                placeholder="Sender envelope email address"
              />
            </FormGroup>
          </FormAccess>
        </FormPanel>
        <FormPanel
          className="kc-email-connection"
          title={t("connectionAndAuthentication")}
        >
          <FormAccess
            isHorizontal
            role="manage-realm"
            className="pf-u-mt-lg"
            onSubmit={handleSubmit(save)}
          >
            <FormGroup
              label={t("host")}
              fieldId="kc-host"
              isRequired
              validated={errors.smtpServer?.host ? "error" : "default"}
              helperTextInvalid={t("common:required")}
            >
              <TextInput
                type="text"
                id="kc-host"
                name="smtpServer.host"
                ref={register({ required: true })}
                placeholder="SMTP host"
                validated={errors.smtpServer?.host ? "error" : "default"}
              />
            </FormGroup>
            <FormGroup label={t("port")} fieldId="kc-port">
              <TextInput
                type="text"
                id="kc-port"
                name="smtpServer.port"
                ref={register}
                placeholder="SMTP port (defaults to 25)"
              />
            </FormGroup>
            <FormGroup label={t("encryption")} fieldId="kc-html-display-name">
              <Controller
                name="smtpServer.ssl"
                control={control}
                defaultValue="false"
                render={({ onChange, value }) => (
                  <Checkbox
                    id="kc-enable-ssl"
                    data-testid="enable-ssl"
                    label={t("enableSSL")}
                    ref={register}
                    isChecked={value === "true"}
                    onChange={(value) => onChange("" + value)}
                  />
                )}
              />
              <Controller
                name="smtpServer.starttls"
                control={control}
                defaultValue="false"
                render={({ onChange, value }) => (
                  <Checkbox
                    id="kc-enable-start-tls"
                    data-testid="enable-start-tls"
                    label={t("enableStartTLS")}
                    ref={register}
                    isChecked={value === "true"}
                    onChange={(value) => onChange("" + value)}
                  />
                )}
              />
            </FormGroup>
            <FormGroup
              hasNoPaddingTop
              label={t("authentication")}
              fieldId="kc-authentication"
            >
              <Controller
                name="smtpServer.authentication"
                control={control}
                defaultValue=""
                render={({ onChange, value }) => (
                  <Switch
                    id="kc-authentication-switch"
                    data-testid="email-authentication-switch"
                    label={t("common:enabled")}
                    labelOff={t("common:disabled")}
                    isChecked={value === "true"}
                    onChange={(value) => {
                      onChange("" + value);
                    }}
                  />
                )}
              />
            </FormGroup>
            {authenticationEnabled === "true" && (
              <>
                <FormGroup
                  label={t("username")}
                  fieldId="kc-username"
                  isRequired
                  validated={errors.smtpServer?.user ? "error" : "default"}
                  helperTextInvalid={t("common:required")}
                >
                  <TextInput
                    type="text"
                    id="kc-username"
                    data-testid="username-input"
                    name="smtpServer.user"
                    ref={register({ required: true })}
                    placeholder="Login username"
                    validated={errors.smtpServer?.user ? "error" : "default"}
                  />
                </FormGroup>
                <FormGroup
                  label={t("password")}
                  fieldId="kc-username"
                  isRequired
                  validated={errors.smtpServer?.password ? "error" : "default"}
                  helperTextInvalid={t("common:required")}
                  labelIcon={
                    <HelpItem
                      helpText="realm-settings-help:password"
                      fieldLabelId="realm-settings:password"
                    />
                  }
                >
                  <TextInput
                    type="password"
                    id="kc-password"
                    data-testid="password-input"
                    name="smtpServer.password"
                    ref={register({ required: true })}
                    placeholder="Login password"
                    validated={
                      errors.smtpServer?.password ? "error" : "default"
                    }
                  />
                </FormGroup>
              </>
            )}

            <ActionGroup>
              <Button
                variant="primary"
                type="submit"
                data-testid="email-tab-save"
              >
                {t("common:save")}
              </Button>
              <Button
                variant="secondary"
                onClick={() => testConnection()}
                data-testid="test-connection-button"
                isDisabled={
                  !(emailRegexPattern.test(watchFromValue) && watchHostValue)
                }
              >
                {t("common:testConnection")}
              </Button>
              <Button variant="link" onClick={reset}>
                {t("common:revert")}
              </Button>
            </ActionGroup>
          </FormAccess>
        </FormPanel>
      </PageSection>
    </>
  );
};