ngx-infinite-scroll/esm2022/lib/services/scroll-resolver.mjs

[](https://travis-ci.org/orizens/ngx-infinite-scroll) [](#backers) [![Sponso

export function shouldFireScrollEvent(container, distance = { down: 0, up: 0 }, scrollingDown) {
    let remaining;
    let containerBreakpoint;
    if (container.totalToScroll <= 0) {
        return false;
    }
    const scrolledUntilNow = container.isWindow
        ? container.scrolled
        : container.height + container.scrolled;
    if (scrollingDown) {
        remaining =
            (container.totalToScroll - scrolledUntilNow) / container.totalToScroll;
        const distanceDown = distance?.down ? distance.down : 0;
        containerBreakpoint = distanceDown / 10;
    }
    else {
        const totalHiddenContentHeight = container.scrolled + (container.totalToScroll - scrolledUntilNow);
        remaining = container.scrolled / totalHiddenContentHeight;
        const distanceUp = distance?.up ? distance.up : 0;
        containerBreakpoint = distanceUp / 10;
    }
    const shouldFireEvent = remaining <= containerBreakpoint;
    return shouldFireEvent;
}
export function isScrollingDownwards(lastScrollPosition, container) {
    return lastScrollPosition < container.scrolled;
}
export function getScrollStats(lastScrollPosition, container, distance) {
    const scrollDown = isScrollingDownwards(lastScrollPosition, container);
    return {
        fire: shouldFireScrollEvent(container, distance, scrollDown),
        scrollDown,
    };
}
export function updateScrollPosition(position, scrollState) {
    return (scrollState.lastScrollPosition = position);
}
export function updateTotalToScroll(totalToScroll, scrollState) {
    if (scrollState.lastTotalToScroll !== totalToScroll) {
        scrollState.lastTotalToScroll = scrollState.totalToScroll;
        scrollState.totalToScroll = totalToScroll;
    }
}
export function isSameTotalToScroll(scrollState) {
    return scrollState.totalToScroll === scrollState.lastTotalToScroll;
}
export function updateTriggeredFlag(scroll, scrollState, triggered, isScrollingDown) {
    if (isScrollingDown) {
        scrollState.triggered.down = scroll;
    }
    else {
        scrollState.triggered.up = scroll;
    }
}
export function isTriggeredScroll(totalToScroll, scrollState, isScrollingDown) {
    return isScrollingDown
        ? scrollState.triggered.down === totalToScroll
        : scrollState.triggered.up === totalToScroll;
}
export function updateScrollState(scrollState, scrolledUntilNow, totalToScroll) {
    updateScrollPosition(scrolledUntilNow, scrollState);
    updateTotalToScroll(totalToScroll, scrollState);
    // const isSameTotal = isSameTotalToScroll(scrollState);
    // if (!isSameTotal) {
    //   updateTriggeredFlag(scrollState, false, isScrollingDown);
    // }
}
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