import classNames from "classnames";
import { useCallback, useEffect, useMemo, useRef } from "react";
import { useTranslation } from "react-i18next";
import { useAsyncFn } from "react-use";

import {
  base64ToBuffer,
  decryptData,
  encryptData,
} from "@/backend/accounts/crypto";
import { getSessions, updateSession } from "@/backend/accounts/sessions";
import { updateSettings } from "@/backend/accounts/settings";
import { editUser } from "@/backend/accounts/user";
import { Button } from "@/components/buttons/Button";
import { WideContainer } from "@/components/layout/WideContainer";
import { UserIcons } from "@/components/UserIcon";
import { Heading1 } from "@/components/utils/Text";
import { Transition } from "@/components/utils/Transition";
import { useAuth } from "@/hooks/auth/useAuth";
import { useBackendUrl } from "@/hooks/auth/useBackendUrl";
import { useIsMobile } from "@/hooks/useIsMobile";
import { useSettingsState } from "@/hooks/useSettingsState";
import { AccountActionsPart } from "@/pages/parts/settings/AccountActionsPart";
import { AccountEditPart } from "@/pages/parts/settings/AccountEditPart";
import { CaptionsPart } from "@/pages/parts/settings/CaptionsPart";
import { ConnectionsPart } from "@/pages/parts/settings/ConnectionsPart";
import { DeviceListPart } from "@/pages/parts/settings/DeviceListPart";
import { RegisterCalloutPart } from "@/pages/parts/settings/RegisterCalloutPart";
import { SidebarPart } from "@/pages/parts/settings/SidebarPart";
import { ThemePart } from "@/pages/parts/settings/ThemePart";
import { PageTitle } from "@/pages/parts/util/PageTitle";
import { AccountWithToken, useAuthStore } from "@/stores/auth";
import { useLanguageStore } from "@/stores/language";
import { usePreferencesStore } from "@/stores/preferences";
import { useSubtitleStore } from "@/stores/subtitles";
import { usePreviewThemeStore, useThemeStore } from "@/stores/theme";

import { SubPageLayout } from "./layouts/SubPageLayout";
import { PreferencesPart } from "./parts/settings/PreferencesPart";

function SettingsLayout(props: { children: React.ReactNode }) {
  const { isMobile } = useIsMobile();

  return (
    <WideContainer ultraWide classNames="overflow-visible">
      <div
        className={classNames(
          "grid gap-12",
          isMobile ? "grid-cols-1" : "lg:grid-cols-[280px,1fr]",
        )}
      >
        <SidebarPart />
        <div>{props.children}</div>
      </div>
    </WideContainer>
  );
}

export function AccountSettings(props: {
  account: AccountWithToken;
  deviceName: string;
  setDeviceName: (s: string) => void;
  colorA: string;
  setColorA: (s: string) => void;
  colorB: string;
  setColorB: (s: string) => void;
  userIcon: UserIcons;
  setUserIcon: (s: UserIcons) => void;
}) {
  const url = useBackendUrl();
  const { account } = props;
  const [sessionsResult, execSessions] = useAsyncFn(() => {
    if (!url) return Promise.resolve([]);
    return getSessions(url, account);
  }, [account, url]);
  useEffect(() => {
    execSessions();
  }, [execSessions]);

  return (
    <>
      <AccountEditPart
        deviceName={props.deviceName}
        setDeviceName={props.setDeviceName}
        colorA={props.colorA}
        setColorA={props.setColorA}
        colorB={props.colorB}
        setColorB={props.setColorB}
        userIcon={props.userIcon}
        setUserIcon={props.setUserIcon}
      />
      <DeviceListPart
        error={!!sessionsResult.error}
        loading={sessionsResult.loading}
        sessions={sessionsResult.value ?? []}
        onChange={execSessions}
      />
      <AccountActionsPart />
    </>
  );
}

export function SettingsPage() {
  const { t } = useTranslation();
  const activeTheme = useThemeStore((s) => s.theme);
  const setTheme = useThemeStore((s) => s.setTheme);
  const previewTheme = usePreviewThemeStore((s) => s.previewTheme);
  const setPreviewTheme = usePreviewThemeStore((s) => s.setPreviewTheme);

  const appLanguage = useLanguageStore((s) => s.language);
  const setAppLanguage = useLanguageStore((s) => s.setLanguage);

  const subStyling = useSubtitleStore((s) => s.styling);
  const setSubStyling = useSubtitleStore((s) => s.updateStyling);

  const proxySet = useAuthStore((s) => s.proxySet);
  const setProxySet = useAuthStore((s) => s.setProxySet);

  const backendUrlSetting = useAuthStore((s) => s.backendUrl);
  const setBackendUrl = useAuthStore((s) => s.setBackendUrl);

  const enableThumbnails = usePreferencesStore((s) => s.enableThumbnails);
  const setEnableThumbnails = usePreferencesStore((s) => s.setEnableThumbnails);

  const account = useAuthStore((s) => s.account);
  const updateProfile = useAuthStore((s) => s.setAccountProfile);
  const updateDeviceName = useAuthStore((s) => s.updateDeviceName);
  const decryptedName = useMemo(() => {
    if (!account) return "";
    return decryptData(account.deviceName, base64ToBuffer(account.seed));
  }, [account]);

  const backendUrl = useBackendUrl();

  const { logout } = useAuth();
  const user = useAuthStore();

  const state = useSettingsState(
    activeTheme,
    appLanguage,
    subStyling,
    decryptedName,
    proxySet,
    backendUrlSetting,
    account?.profile,
    enableThumbnails,
  );

  useEffect(() => {
    setPreviewTheme(activeTheme ?? "default");
  }, [setPreviewTheme, activeTheme]);

  useEffect(() => {
    // Clear preview theme on unmount
    return () => {
      setPreviewTheme(null);
    };
  }, [setPreviewTheme]);

  const setThemeWithPreview = useCallback(
    (theme: string) => {
      state.theme.set(theme === "default" ? null : theme);
      setPreviewTheme(theme);
    },
    [state.theme, setPreviewTheme],
  );

  const saveChanges = useCallback(async () => {
    if (account && backendUrl) {
      if (
        state.appLanguage.changed ||
        state.theme.changed ||
        state.proxyUrls.changed
      ) {
        await updateSettings(backendUrl, account, {
          applicationLanguage: state.appLanguage.state,
          applicationTheme: state.theme.state,
          proxyUrls: state.proxyUrls.state?.filter((v) => v !== "") ?? null,
        });
      }
      if (state.deviceName.changed) {
        const newDeviceName = await encryptData(
          state.deviceName.state,
          base64ToBuffer(account.seed),
        );
        await updateSession(backendUrl, account, {
          deviceName: newDeviceName,
        });
        updateDeviceName(newDeviceName);
      }
      if (state.profile.changed) {
        await editUser(backendUrl, account, {
          profile: state.profile.state,
        });
      }
    }

    setEnableThumbnails(state.enableThumbnails.state);
    setAppLanguage(state.appLanguage.state);
    setTheme(state.theme.state);
    setSubStyling(state.subtitleStyling.state);
    setProxySet(state.proxyUrls.state?.filter((v) => v !== "") ?? null);

    if (state.profile.state) {
      updateProfile(state.profile.state);
    }

    // when backend url gets changed, log the user out first
    if (state.backendUrl.changed) {
      await logout();

      let url = state.backendUrl.state;
      if (url && !url.startsWith("http://") && !url.startsWith("https://")) {
        url = `https://${url}`;
      }

      setBackendUrl(url);
    }
  }, [
    state,
    account,
    backendUrl,
    setEnableThumbnails,
    setAppLanguage,
    setTheme,
    setSubStyling,
    updateDeviceName,
    updateProfile,
    setProxySet,
    setBackendUrl,
    logout,
  ]);
  return (
    <SubPageLayout>
      <PageTitle subpage k="global.pages.settings" />
      <SettingsLayout>
        <div id="settings-account">
          <Heading1 border className="!mb-0">
            {t("settings.account.title")}
          </Heading1>
          {user.account && state.profile.state ? (
            <AccountSettings
              account={user.account}
              deviceName={state.deviceName.state}
              setDeviceName={state.deviceName.set}
              colorA={state.profile.state.colorA}
              setColorA={(v) => {
                state.profile.set((s) => (s ? { ...s, colorA: v } : undefined));
              }}
              colorB={state.profile.state.colorB}
              setColorB={(v) =>
                state.profile.set((s) => (s ? { ...s, colorB: v } : undefined))
              }
              userIcon={state.profile.state.icon as any}
              setUserIcon={(v) =>
                state.profile.set((s) => (s ? { ...s, icon: v } : undefined))
              }
            />
          ) : (
            <RegisterCalloutPart />
          )}
        </div>
        <div id="settings-preferences" className="mt-48">
          <PreferencesPart
            language={state.appLanguage.state}
            setLanguage={state.appLanguage.set}
            enableThumbnails={state.enableThumbnails.state}
            setEnableThumbnails={state.enableThumbnails.set}
          />
        </div>
        <div id="settings-appearance" className="mt-48">
          <ThemePart
            active={previewTheme ?? "default"}
            inUse={activeTheme ?? "default"}
            setTheme={setThemeWithPreview}
          />
        </div>
        <div id="settings-captions" className="mt-48">
          <CaptionsPart
            styling={state.subtitleStyling.state}
            setStyling={state.subtitleStyling.set}
          />
        </div>
        <div id="settings-connection" className="mt-48">
          <ConnectionsPart
            backendUrl={state.backendUrl.state}
            setBackendUrl={state.backendUrl.set}
            proxyUrls={state.proxyUrls.state}
            setProxyUrls={state.proxyUrls.set}
          />
        </div>
      </SettingsLayout>
      <Transition
        animation="fade"
        show={state.changed}
        className="bg-settings-saveBar-background border-t border-settings-card-border/50 py-4 transition-opacity w-full fixed bottom-0 flex justify-between flex-col md:flex-row px-8 items-start md:items-center gap-3"
      >
        <p className="text-type-danger">{t("settings.unsaved")}</p>
        <div className="space-x-3 w-full md:w-auto flex">
          <Button
            className="w-full md:w-auto"
            theme="secondary"
            onClick={state.reset}
          >
            {t("settings.reset")}
          </Button>
          <Button
            className="w-full md:w-auto"
            theme="purple"
            onClick={saveChanges}
          >
            {t("settings.save")}
          </Button>
        </div>
      </Transition>
    </SubPageLayout>
  );
}

export default SettingsPage;