import React, { useReducer, useEffect } from "react";
import { assert } from "./tools/assert";
import { headInsert } from "./tools/headInsert";
import { pathJoin } from "./bin/tools/pathJoin";
import { clsx } from "./tools/clsx";
import type { TemplateProps } from "./KcProps";
import type { KcContextBase } from "./kcContext/KcContextBase";
import type { I18nBase } from "./i18n";

export default function Template(props: TemplateProps<KcContextBase.Common, I18nBase>) {
    const {
        displayInfo = false,
        displayMessage = true,
        displayRequiredFields = false,
        displayWide = false,
        showAnotherWayIfPresent = true,
        headerNode,
        showUsernameNode = null,
        formNode,
        infoNode = null,
        kcContext,
        i18n,
        doFetchDefaultThemeResources,
        stylesCommon,
        styles,
        scripts,
        kcHtmlClass
    } = props;

    const { msg, changeLocale, labelBySupportedLanguageTag, currentLanguageTag } = i18n;

    const { realm, locale, auth, url, message, isAppInitiatedAction } = kcContext;

    const { isReady } = usePrepareTemplate({
        doFetchDefaultThemeResources,
        stylesCommon,
        styles,
        scripts,
        url,
        kcHtmlClass
    });

    if (!isReady) {
        return null;
    }

    return (
        <div className={clsx(props.kcLoginClass)}>
            <div id="kc-header" className={clsx(props.kcHeaderClass)}>
                <div id="kc-header-wrapper" className={clsx(props.kcHeaderWrapperClass)}>
                    {msg("loginTitleHtml", realm.displayNameHtml)}
                </div>
            </div>

            <div className={clsx(props.kcFormCardClass, displayWide && props.kcFormCardAccountClass)}>
                <header className={clsx(props.kcFormHeaderClass)}>
                    {realm.internationalizationEnabled && (assert(locale !== undefined), true) && locale.supported.length > 1 && (
                        <div id="kc-locale">
                            <div id="kc-locale-wrapper" className={clsx(props.kcLocaleWrapperClass)}>
                                <div className="kc-dropdown" id="kc-locale-dropdown">
                                    {/* eslint-disable-next-line jsx-a11y/anchor-is-valid */}
                                    <a href="#" id="kc-current-locale-link">
                                        {labelBySupportedLanguageTag[currentLanguageTag]}
                                    </a>
                                    <ul>
                                        {locale.supported.map(({ languageTag }) => (
                                            <li key={languageTag} className="kc-dropdown-item">
                                                {/* eslint-disable-next-line jsx-a11y/anchor-is-valid */}
                                                <a href="#" onClick={() => changeLocale(languageTag)}>
                                                    {labelBySupportedLanguageTag[languageTag]}
                                                </a>
                                            </li>
                                        ))}
                                    </ul>
                                </div>
                            </div>
                        </div>
                    )}
                    {!(auth !== undefined && auth.showUsername && !auth.showResetCredentials) ? (
                        displayRequiredFields ? (
                            <div className={clsx(props.kcContentWrapperClass)}>
                                <div className={clsx(props.kcLabelWrapperClass, "subtitle")}>
                                    <span className="subtitle">
                                        <span className="required">*</span>
                                        {msg("requiredFields")}
                                    </span>
                                </div>
                                <div className="col-md-10">
                                    <h1 id="kc-page-title">{headerNode}</h1>
                                </div>
                            </div>
                        ) : (
                            <h1 id="kc-page-title">{headerNode}</h1>
                        )
                    ) : displayRequiredFields ? (
                        <div className={clsx(props.kcContentWrapperClass)}>
                            <div className={clsx(props.kcLabelWrapperClass, "subtitle")}>
                                <span className="subtitle">
                                    <span className="required">*</span> {msg("requiredFields")}
                                </span>
                            </div>
                            <div className="col-md-10">
                                {showUsernameNode}
                                <div className={clsx(props.kcFormGroupClass)}>
                                    <div id="kc-username">
                                        <label id="kc-attempted-username">{auth?.attemptedUsername}</label>
                                        <a id="reset-login" href={url.loginRestartFlowUrl}>
                                            <div className="kc-login-tooltip">
                                                <i className={clsx(props.kcResetFlowIcon)}></i>
                                                <span className="kc-tooltip-text">{msg("restartLoginTooltip")}</span>
                                            </div>
                                        </a>
                                    </div>
                                </div>
                            </div>
                        </div>
                    ) : (
                        <>
                            {showUsernameNode}
                            <div className={clsx(props.kcFormGroupClass)}>
                                <div id="kc-username">
                                    <label id="kc-attempted-username">{auth?.attemptedUsername}</label>
                                    <a id="reset-login" href={url.loginRestartFlowUrl}>
                                        <div className="kc-login-tooltip">
                                            <i className={clsx(props.kcResetFlowIcon)}></i>
                                            <span className="kc-tooltip-text">{msg("restartLoginTooltip")}</span>
                                        </div>
                                    </a>
                                </div>
                            </div>
                        </>
                    )}
                </header>
                <div id="kc-content">
                    <div id="kc-content-wrapper">
                        {/* App-initiated actions should not see warning messages about the need to complete the action during login. */}
                        {displayMessage && message !== undefined && (message.type !== "warning" || !isAppInitiatedAction) && (
                            <div className={clsx("alert", `alert-${message.type}`)}>
                                {message.type === "success" && <span className={clsx(props.kcFeedbackSuccessIcon)}></span>}
                                {message.type === "warning" && <span className={clsx(props.kcFeedbackWarningIcon)}></span>}
                                {message.type === "error" && <span className={clsx(props.kcFeedbackErrorIcon)}></span>}
                                {message.type === "info" && <span className={clsx(props.kcFeedbackInfoIcon)}></span>}
                                <span
                                    className="kc-feedback-text"
                                    dangerouslySetInnerHTML={{
                                        "__html": message.summary
                                    }}
                                />
                            </div>
                        )}
                        {formNode}
                        {auth !== undefined && auth.showTryAnotherWayLink && showAnotherWayIfPresent && (
                            <form
                                id="kc-select-try-another-way-form"
                                action={url.loginAction}
                                method="post"
                                className={clsx(displayWide && props.kcContentWrapperClass)}
                            >
                                <div className={clsx(displayWide && [props.kcFormSocialAccountContentClass, props.kcFormSocialAccountClass])}>
                                    <div className={clsx(props.kcFormGroupClass)}>
                                        <input type="hidden" name="tryAnotherWay" value="on" />
                                        {/* eslint-disable-next-line jsx-a11y/anchor-is-valid */}
                                        <a
                                            href="#"
                                            id="try-another-way"
                                            onClick={() => {
                                                document.forms["kc-select-try-another-way-form" as never].submit();
                                                return false;
                                            }}
                                        >
                                            {msg("doTryAnotherWay")}
                                        </a>
                                    </div>
                                </div>
                            </form>
                        )}
                        {displayInfo && (
                            <div id="kc-info" className={clsx(props.kcSignUpClass)}>
                                <div id="kc-info-wrapper" className={clsx(props.kcInfoAreaWrapperClass)}>
                                    {infoNode}
                                </div>
                            </div>
                        )}
                    </div>
                </div>
            </div>
        </div>
    );
}

export function usePrepareTemplate(params: {
    doFetchDefaultThemeResources: boolean;
    stylesCommon: string | readonly string[] | undefined;
    styles: string | readonly string[] | undefined;
    scripts: string | readonly string[] | undefined;
    url: {
        resourcesCommonPath: string;
        resourcesPath: string;
    };
    kcHtmlClass: string | readonly string[] | undefined;
}) {
    const { doFetchDefaultThemeResources, stylesCommon, styles, url, scripts, kcHtmlClass } = params;

    const [isReady, setReady] = useReducer(() => true, !doFetchDefaultThemeResources);

    useEffect(() => {
        if (!doFetchDefaultThemeResources) {
            return;
        }

        let isUnmounted = false;

        const toArr = (x: string | readonly string[] | undefined) => (typeof x === "string" ? x.split(" ") : x ?? []);

        Promise.all(
            [
                ...toArr(stylesCommon).map(relativePath => pathJoin(url.resourcesCommonPath, relativePath)),
                ...toArr(styles).map(relativePath => pathJoin(url.resourcesPath, relativePath))
            ]
                .reverse()
                .map(href =>
                    headInsert({
                        "type": "css",
                        href,
                        "position": "prepend"
                    })
                )
        ).then(() => {
            if (isUnmounted) {
                return;
            }

            setReady();
        });

        toArr(scripts).forEach(relativePath =>
            headInsert({
                "type": "javascript",
                "src": pathJoin(url.resourcesPath, relativePath)
            })
        );

        return () => {
            isUnmounted = true;
        };
    }, [kcHtmlClass]);

    useEffect(() => {
        if (kcHtmlClass === undefined) {
            return;
        }

        const htmlClassList = document.getElementsByTagName("html")[0].classList;

        const tokens = clsx(kcHtmlClass).split(" ");

        htmlClassList.add(...tokens);

        return () => {
            htmlClassList.remove(...tokens);
        };
    }, [kcHtmlClass]);

    return { isReady };
}