import type { UNode, UElement, URoot, UType, UComponent, UniversalProps } from "./schema.js";

let _idCounter = 0;

export function h(type: UType, props?: UniversalProps | null, ...children: UNode[]): UElement | URoot {
  const flatChildren = children.flat(Infinity as 1).filter((c: UNode) => c != null && c !== false) as UNode[];

  if (type === "root") {
    return {
      type: "root",
      props: { ...(props ?? {}) },
      children: flatChildren,
    } as URoot;
  }

  const { key, ...restProps } = props ?? {};
  const resolvedProps: UniversalProps = restProps;

  return {
    type: type as string,
    props: resolvedProps,
    children: flatChildren,
    ...(key != null ? { key: key as string } : {}),
  } as UElement;
}

export function createRoot(id: string | undefined, ...children: UNode[]): URoot {
  return {
    type: "root",
    props: { id: id ?? `root_${++_idCounter}` },
    children: children.flat(Infinity as 1).filter((c: UNode) => c != null && c !== false) as UNode[],
  };
}

export function createComponent<P extends UniversalProps>(
  name: string,
  render: (props: P) => UNode,
  targets?: string[],
): UComponent<P> {
  const c = render as unknown as UComponent<P>;
  c.displayName = name;
  c.targets = targets;
  return c;
}

export function Fragment(props: { children?: UNode[] }): UNode[] {
  return ((props.children ?? []) as UNode[]).flat(Infinity as 1).filter((c: UNode) => c != null && c !== false) as UNode[];
}

export const jsx = h;
export const jsxs = h;
export const jsxDEV = h;