import { addEventListener, addMeltEventListener, makeElement, createElHelpers, effect, executeCallbacks, generateIds, isHTMLElement, noop, styleToString, toWritableStores, omit, withGet, } from '../../internal/helpers/index.js';
import { derived, writable } from 'svelte/store';
import { addUnlinkedScrollListener, getScrollPositionFromPointer, getThumbOffsetFromScroll, getThumbRatio, isScrollingWithinScrollbarBounds, toInt, } from './helpers.js';
import { createScrollbarX, createScrollbarY, getScrollbarActionByType } from './scrollbars.js';
export const { name } = createElHelpers('scroll-area');
export const scrollAreaIdParts = [
    'root',
    'viewport',
    'content',
    'scrollbarX',
    'scrollbarY',
    'thumbX',
    'thumbY',
];
const defaults = {
    type: 'hover',
    hideDelay: 600,
    dir: 'ltr',
};
export function createScrollArea(props) {
    const withDefaults = { ...defaults, ...props };
    const options = toWritableStores(omit(withDefaults, 'ids'));
    const cornerWidth = withGet.writable(0);
    const cornerHeight = withGet.writable(0);
    const scrollbarXEnabled = withGet.writable(false);
    const scrollbarYEnabled = withGet.writable(false);
    const scrollAreaEl = withGet.writable(null);
    const viewportEl = withGet.writable(null);
    const contentEl = withGet.writable(null);
    const scrollbarXEl = withGet.writable(null);
    const scrollbarYEl = withGet.writable(null);
    const ids = toWritableStores({ ...generateIds(scrollAreaIdParts), ...withDefaults.ids });
    const rootState = {
        cornerWidth,
        cornerHeight,
        scrollbarXEnabled,
        scrollbarYEnabled,
        viewportEl,
        contentEl,
        options,
        scrollbarXEl,
        scrollbarYEl,
        scrollAreaEl,
        ids,
    };
    const root = makeElement(name(), {
        stores: [cornerWidth, cornerHeight, ids.root],
        returned: ([$cornerWidth, $cornderHeight, $rootId]) => {
            return {
                style: styleToString({
                    position: 'relative',
                    '--melt-scroll-area-corner-width': `${$cornerWidth}px`,
                    '--melt-scroll-area-corner-height': `${$cornderHeight}px`,
                }),
                id: $rootId,
            };
        },
        action: (node) => {
            scrollAreaEl.set(node);
            return {
                destroy() {
                    scrollAreaEl.set(null);
                },
            };
        },
    });
    const viewport = makeElement(name('viewport'), {
        stores: [scrollbarXEnabled, scrollbarYEnabled, ids.viewport],
        returned: ([$scrollbarXEnabled, $scrollbarYEnabled, $viewportId]) => {
            return {
                style: styleToString({
                    'scrollbar-width': 'none',
                    '-ms-overflow-style': 'none',
                    '-webkit-overflow-scrolling': 'touch',
                    '-webkit-scrollbar': 'none',
                    'overflow-x': $scrollbarXEnabled ? 'scroll' : 'hidden',
                    'overflow-y': $scrollbarYEnabled ? 'scroll' : 'hidden',
                }),
                id: $viewportId,
            };
        },
        action: (node) => {
            // Ensure we hide any native scrollbars on the viewport element
            const styleNode = document.createElement('style');
            styleNode.innerHTML = `
				/* Hide scrollbars cross-browser and enable momentum scroll for touch
					devices */
				[data-melt-scroll-area-viewport] {
					scrollbar-width: none;
					-ms-overflow-style: none;
					-webkit-overflow-scrolling: touch;
				}

				[data-melt-scroll-area-viewport]::-webkit-scrollbar {
					display: none;
				}
			`;
            node.parentElement?.insertBefore(styleNode, node);
            viewportEl.set(node);
            return {
                destroy() {
                    styleNode.remove();
                    viewportEl.set(null);
                },
            };
        },
    });
    const content = makeElement(name('content'), {
        stores: [ids.content],
        returned: ([$contentId]) => {
            return {
                style: styleToString({
                    'min-width': '100%',
                    display: 'table',
                }),
                id: $contentId,
            };
        },
        action: (node) => {
            contentEl.set(node);
            return {
                destroy() {
                    contentEl.set(null);
                },
            };
        },
    });
    function createScrollbar(orientationProp = 'vertical') {
        const orientation = withGet.writable(orientationProp);
        const isHorizontal = withGet.writable(orientationProp === 'horizontal');
        const domRect = withGet.writable(null);
        const prevWebkitUserSelect = withGet.writable('');
        const pointerOffset = withGet.writable(0);
        const thumbEl = withGet.writable(null);
        const thumbOffset = withGet.writable(0);
        const scrollbarEl = withGet.writable(null);
        const sizes = withGet.writable({
            content: 0,
            viewport: 0,
            scrollbar: {
                size: 0,
                paddingStart: 0,
                paddingEnd: 0,
            },
        });
        const isVisible = withGet.writable(false);
        const hasThumb = withGet.derived(sizes, ($sizes) => {
            const thumbRatio = getThumbRatio($sizes.viewport, $sizes.content);
            return Boolean(thumbRatio > 0 && thumbRatio < 1);
        });
        function getScrollPosition(pointerPos, dir) {
            return getScrollPositionFromPointer(pointerPos, pointerOffset.get(), sizes.get(), dir);
        }
        function handleWheelScroll(e, payload) {
            const $viewportEl = viewportEl.get();
            if (!$viewportEl)
                return;
            if (isHorizontal.get()) {
                const scrollPos = $viewportEl.scrollLeft + e.deltaY;
                $viewportEl.scrollLeft = scrollPos;
                if (isScrollingWithinScrollbarBounds(scrollPos, payload)) {
                    e.preventDefault();
                }
            }
            else {
                const scrollPos = $viewportEl.scrollTop + e.deltaY;
                $viewportEl.scrollTop = scrollPos;
                if (isScrollingWithinScrollbarBounds(scrollPos, payload)) {
                    e.preventDefault();
                }
            }
        }
        function handleThumbDown(payload) {
            if (isHorizontal.get()) {
                pointerOffset.set(payload.x);
            }
            else {
                pointerOffset.set(payload.y);
            }
        }
        function handleThumbUp() {
            pointerOffset.set(0);
        }
        function onThumbPositionChange() {
            const $viewportEl = viewportEl.get();
            const $thumbEl = thumbEl.get();
            if (!$viewportEl || !$thumbEl)
                return;
            const scrollPos = isHorizontal.get() ? $viewportEl.scrollLeft : $viewportEl.scrollTop;
            const offset = getThumbOffsetFromScroll(scrollPos, sizes.get(), rootState.options.dir.get());
            thumbOffset.set(offset);
        }
        function onDragScroll(payload) {
            const $viewportEl = viewportEl.get();
            if (!$viewportEl)
                return;
            if (isHorizontal.get()) {
                $viewportEl.scrollLeft = getScrollPosition(payload, rootState.options.dir.get());
            }
            else {
                $viewportEl.scrollTop = getScrollPosition(payload);
            }
        }
        function handleSizeChange() {
            const $scrollbarEl = scrollbarState.scrollbarEl.get();
            if (!$scrollbarEl)
                return;
            const $isHorizontal = scrollbarState.isHorizontal.get();
            const $viewportEl = rootState.viewportEl.get();
            if ($isHorizontal) {
                scrollbarState.sizes.set({
                    content: $viewportEl?.scrollWidth ?? 0,
                    viewport: $viewportEl?.offsetWidth ?? 0,
                    scrollbar: {
                        size: $scrollbarEl.clientWidth ?? 0,
                        paddingStart: toInt(getComputedStyle($scrollbarEl).paddingLeft),
                        paddingEnd: toInt(getComputedStyle($scrollbarEl).paddingRight),
                    },
                });
            }
            else {
                scrollbarState.sizes.set({
                    content: $viewportEl?.scrollHeight ?? 0,
                    viewport: $viewportEl?.offsetHeight ?? 0,
                    scrollbar: {
                        size: $scrollbarEl.clientHeight ?? 0,
                        paddingStart: toInt(getComputedStyle($scrollbarEl).paddingLeft),
                        paddingEnd: toInt(getComputedStyle($scrollbarEl).paddingRight),
                    },
                });
            }
        }
        const scrollbarState = {
            isHorizontal,
            domRect,
            prevWebkitUserSelect,
            pointerOffset,
            thumbEl,
            thumbOffset,
            sizes,
            orientation,
            handleThumbDown,
            handleThumbUp,
            onThumbPositionChange,
            onDragScroll,
            handleWheelScroll,
            hasThumb,
            scrollbarEl,
            isVisible,
            handleSizeChange,
        };
        const scrollbarActionByType = getScrollbarActionByType(options.type.get());
        const scrollAreaState = { rootState, scrollbarState };
        const scrollbar = orientationProp === 'horizontal'
            ? createScrollbarX(scrollAreaState, scrollbarActionByType)
            : createScrollbarY(scrollAreaState, scrollbarActionByType);
        const thumb = createScrollbarThumb(scrollAreaState);
        return {
            scrollbar,
            thumb,
        };
    }
    const { scrollbar: scrollbarX, thumb: thumbX } = createScrollbar('horizontal');
    const { scrollbar: scrollbarY, thumb: thumbY } = createScrollbar('vertical');
    const corner = createScrollAreaCorner(rootState);
    return {
        options,
        elements: {
            root,
            viewport,
            content,
            corner,
            scrollbarX,
            scrollbarY,
            thumbX,
            thumbY,
        },
    };
}
function createScrollbarThumb(state) {
    const { scrollbarState, rootState } = state;
    function handlePointerDown(e) {
        const thumb = e.target;
        if (!isHTMLElement(thumb))
            return;
        const thumbRect = thumb.getBoundingClientRect();
        const x = e.clientX - thumbRect.left;
        const y = e.clientY - thumbRect.top;
        scrollbarState.handleThumbDown({ x, y });
    }
    function handlePointerUp(e) {
        scrollbarState.handleThumbUp(e);
    }
    let unsubListener = undefined;
    function handleScroll() {
        if (unsubListener)
            return;
        const $viewportEl = rootState.viewportEl.get();
        if ($viewportEl) {
            unsubListener = addUnlinkedScrollListener($viewportEl, scrollbarState.onThumbPositionChange);
        }
        scrollbarState.onThumbPositionChange();
    }
    const thumb = makeElement(name('thumb'), {
        stores: [scrollbarState.hasThumb, scrollbarState.isHorizontal, scrollbarState.thumbOffset],
        returned: ([$hasThumb, $isHorizontal, $offset]) => {
            return {
                style: styleToString({
                    width: 'var(--melt-scroll-area-thumb-width)',
                    height: 'var(--melt-scroll-area-thumb-height)',
                    transform: $isHorizontal
                        ? `translate3d(${Math.round($offset)}px, 0, 0)`
                        : `translate3d(0, ${Math.round($offset)}px, 0)`,
                }),
                'data-state': $hasThumb ? 'visible' : 'hidden',
            };
        },
        action: (node) => {
            scrollbarState.thumbEl.set(node);
            const unsubEffect = effect([scrollbarState.sizes], ([_]) => {
                const $viewportEl = rootState.viewportEl.get();
                if (!$viewportEl)
                    return noop;
                scrollbarState.onThumbPositionChange();
                return addEventListener($viewportEl, 'scroll', handleScroll);
            });
            const unsubEvents = executeCallbacks(addMeltEventListener(node, 'pointerdown', handlePointerDown), addMeltEventListener(node, 'pointerup', handlePointerUp));
            return {
                destroy() {
                    unsubListener?.();
                    unsubEvents();
                    unsubEffect();
                },
            };
        },
    });
    return thumb;
}
function createScrollAreaCorner(rootState) {
    const width = writable(0);
    const height = writable(0);
    const hasSize = derived([width, height], ([$width, $height]) => !!$width && !!$height);
    function setCornerHeight() {
        const offsetHeight = rootState.scrollbarXEl.get()?.offsetHeight || 0;
        rootState.cornerHeight.set(offsetHeight);
        height.set(offsetHeight);
    }
    function setCornerWidth() {
        const offsetWidth = rootState.scrollbarYEl.get()?.offsetWidth || 0;
        rootState.cornerWidth.set(offsetWidth);
        width.set(offsetWidth);
    }
    effect([rootState.scrollbarXEl], ([$scrollbarXEl]) => {
        if ($scrollbarXEl) {
            setCornerHeight();
        }
    });
    effect([rootState.scrollbarYEl], ([$scrollbarYEl]) => {
        if ($scrollbarYEl) {
            setCornerWidth();
        }
    });
    const hasBothScrollbarsVisible = derived([rootState.scrollbarXEl, rootState.scrollbarYEl], ([$scrollbarXEl, $scrollbarYEl]) => {
        return !!$scrollbarXEl && !!$scrollbarYEl;
    });
    const hasCorner = derived([rootState.options.type, hasBothScrollbarsVisible], ([$type, $hasBoth]) => {
        return $type !== 'scroll' && $hasBoth;
    });
    const shouldDisplay = derived([hasCorner, hasSize], ([$hasCorner, $hasSize]) => $hasCorner && $hasSize);
    const corner = makeElement(name('corner'), {
        stores: [width, height, rootState.options.dir, shouldDisplay],
        returned: ([$width, $height, $dir, $shouldDisplay]) => {
            return {
                style: styleToString({
                    display: $shouldDisplay ? 'block' : 'none',
                    width: `${$width}px`,
                    height: `${$height}px`,
                    position: 'absolute',
                    right: $dir === 'ltr' ? 0 : undefined,
                    left: $dir === 'rtl' ? 0 : undefined,
                    bottom: 0,
                }),
            };
        },
    });
    return corner;
}