"use client";

import React, { useEffect, useRef } from "react";

const DEFAULT_REMOTE_URL = "https://uikit.d.aiengines.ir/AppHeader.js";
const APP_HEADER_SLOT = Symbol.for("uikit.remote.app-header.slot");
const remotePromises = new Map();

function loadRemote(componentName, remoteFileUrl) {
  const cacheKey = `${componentName}:${remoteFileUrl}`;
  if (!remotePromises.has(cacheKey)) {
    remotePromises.set(
      cacheKey,
      import(
        /* webpackIgnore: true */
        /* @vite-ignore */
        remoteFileUrl
      ).catch((error) => {
        remotePromises.delete(cacheKey);
        throw error;
      }),
    );
  }
  return remotePromises.get(cacheKey);
}

function createRemoteElementComponent({ componentName, tagName, defaultRemoteUrl, normalizeProps }) {
  return function RemoteElementComponent(props) {
    const containerRef = useRef(null);
    const elementRef = useRef(null);
    const latestPropsRef = useRef(null);
    latestPropsRef.current = normalizeProps ? normalizeProps(props) : props;

    useEffect(() => {
      let active = true;
      loadRemote(componentName, defaultRemoteUrl)
        .then(() => {
          if (!active || !containerRef.current) return;
          const element = document.createElement(tagName);
          element.componentProps = latestPropsRef.current;
          containerRef.current.appendChild(element);
          elementRef.current = element;
        })
        .catch((error) => {
          console.error(`[uikit/remote/ui] Failed to load ${componentName}:`, error);
        });

      return () => {
        active = false;
        if (elementRef.current) {
          elementRef.current.remove();
          elementRef.current = null;
        }
      };
    }, [componentName, defaultRemoteUrl, tagName]);

    useEffect(() => {
      if (elementRef.current) {
        elementRef.current.componentProps = latestPropsRef.current;
      }
    });

    return React.createElement("span", {
      ref: containerRef,
      style: { display: "contents" },
    });
  };
}

function createAppHeaderSlot(name) {
  function AppHeaderSlot() {
    return null;
  }
  AppHeaderSlot[APP_HEADER_SLOT] = name;
  return AppHeaderSlot;
}

const BrandSection = createAppHeaderSlot("brandSection");
const Logo = createAppHeaderSlot("logo");
const Brand = createAppHeaderSlot("brand");
const Title = createAppHeaderSlot("title");
const Description = createAppHeaderSlot("description");
const Bi = createAppHeaderSlot("bi");

function toPlainText(value) {
  if (value === null || value === undefined || typeof value === "boolean") return undefined;
  if (typeof value === "string" || typeof value === "number") return String(value);
  if (Array.isArray(value)) return value.map(toPlainText).filter(Boolean).join("");
  if (React.isValidElement(value)) return toPlainText(value.props?.children);
  return undefined;
}

function extractCompoundAppHeader(children) {
  const result = { showBi: false };

  function visit(node) {
    React.Children.forEach(node, (child) => {
      if (!React.isValidElement(child)) return;
      const slot = child.type?.[APP_HEADER_SLOT];

      if (slot === "logo") {
        result.logoSrc = child.props.src;
        result.logoAlt = child.props.alt;
      } else if (slot === "title") {
        result.title = toPlainText(child.props.children);
      } else if (slot === "description") {
        result.description = toPlainText(child.props.children);
      } else if (slot === "bi") {
        result.showBi = true;
        result.biLogoSrc = child.props.logoSrc || child.props.src;
        result.biLogoAlt = child.props.alt;
        result.biText = child.props.text;
      }

      if (child.props?.children) visit(child.props.children);
    });
  }

  visit(children);
  return result;
}

const RemoteAppHeaderElement = createRemoteElementComponent({
  componentName: "AppHeader",
  tagName: "uikit-app-header",
  defaultRemoteUrl: DEFAULT_REMOTE_URL,
  normalizeProps: ({ children, ...props }) =>
    children === undefined || children === null
      ? props
      : { ...props, ...extractCompoundAppHeader(children) },
});

function AppHeaderRoot(props) {
  return React.createElement(RemoteAppHeaderElement, props);
}

export const AppHeader = Object.assign(AppHeaderRoot, {
  BrandSection,
  Logo,
  Brand,
  Title,
  Description,
  Bi,
});