import { KNOWN_ELEMENTS } from "./elementTags.js";
import {
  Fragment,
  JSXChildTypes,
  NonBooleanPrimitive,
  VNode,
} from "./types.js";
import { flattenVNodes } from "./utils.js";

/**
 * Creates a virtual element representing a DOM node or Fragment.
 * @param type Element type (tag name) or Fragment
 * @param props Properties and attributes for the element
 * @param children Child elements or content
 * @returns Virtual element representation
 */
export function createElement(
  type: string | typeof Fragment,
  props: { [key: string]: unknown } | null,
  ...children: JSXChildTypes[]
): VNode | VNode[] {
  if (typeof type === "string") {
    const normalizedProps: { [key: string]: unknown } = props ? props : {};

    const flatChildren: VNode[] = flattenVNodes(children);

    if (flatChildren.length > 0) {
      // Set children property only if dangerouslySetInnerHTML is not present
      if (!normalizedProps.dangerouslySetInnerHTML) {
        normalizedProps.children = flatChildren;
      } else {
        normalizedProps.children = [];
        console.warn(
          "WebJSX: Ignoring children since dangerouslySetInnerHTML is set."
        );
      }
    } else {
      normalizedProps.children = [];
    }

    const result: VNode = {
      type,
      tagName: KNOWN_ELEMENTS.get(type) ?? type.toUpperCase(),
      props: normalizedProps ?? {},
    };
    return result;
  } else {
    return flattenVNodes(children);
  }
}

// As called from jsx-runtime.jsx function.
export function createElementJSX(
  type: string | typeof Fragment,
  props: { [key: string]: unknown } | null,
  key?: NonBooleanPrimitive
): VNode | VNode[] {
  if (typeof type === "string") {
    props = props || {};
    const flatChildren: VNode[] = props
      ? flattenVNodes(props.children as JSXChildTypes)
      : [];

    if (key !== undefined) {
      props.key = key;
    }

    if (flatChildren.length > 0) {
      // Set children property only if dangerouslySetInnerHTML is not present
      if (!props.dangerouslySetInnerHTML) {
        props.children = flatChildren;
      } else {
        props.children = [];
        console.warn(
          "WebJSX: Ignoring children since dangerouslySetInnerHTML is set."
        );
      }
    } else {
      props.children = [];
    }

    const result: VNode = {
      type,
      tagName: KNOWN_ELEMENTS.get(type) ?? type.toUpperCase(),
      props: props ?? {},
    };
    return result;
  } else {
    const flatChildren: VNode[] = props
      ? flattenVNodes(props.children as JSXChildTypes)
      : [];
    return flatChildren;
  }
}