import { atom, computed } from "@cn-ui/reactive";
import { type Accessor, onCleanup, onMount } from "solid-js";
import { useResizeObserver } from "solidjs-use";

/** 自动根据父元素的大小变更自己的大小 */
export const useAutoResize = (ElRef: Accessor<HTMLElement | null>) => {
    const width$ = atom(0);
    const height$ = atom(0);

    const sizer = computed<HTMLElement | null>(() => ElRef()?.parentElement!);
    onMount(() => sizer.recomputed());

    let resizerStopper: ReturnType<typeof useResizeObserver>["stop"];
    onMount(() => {
        resizerStopper = useResizeObserver(sizer, ([entry]) => {
            const { width, height } = entry.contentRect;
            const { paddingLeft, paddingRight, paddingTop, paddingBottom } = getComputedStyle(
                entry.target,
            );

            const left = Number.parseInt(paddingLeft) || 0;
            const right = Number.parseInt(paddingRight) || 0;
            const top = Number.parseInt(paddingTop) || 0;
            const bottom = Number.parseInt(paddingBottom) || 0;

            width$(width - left - right);
            height$(height - top - bottom);
        }).stop;
    });

    onCleanup(() => {
        resizerStopper?.();
    });

    return {
        sizer,
        width: width$,
        height: height$,
    };
};