/** Grid selection helpers extracted from GridView_impl.js (P3-B-03). */

export function getSelectedIdSet(gridContainer: any): Set<string> {
    const selected = new Set<string>();
    if (!gridContainer) return selected;
    try {
        const raw = gridContainer.dataset?.mjrSelectedAssetIds;
        if (raw) {
            const parsed = JSON.parse(raw);
            if (Array.isArray(parsed)) {
                for (const id of parsed) {
                    if (id == null) continue;
                    selected.add(String(id));
                }
            }
            return selected;
        }
    } catch (e: any) {
        console.warn("[MJR] selection state parse error:", e);
    }
    try {
        const id = gridContainer.dataset?.mjrSelectedAssetId;
        if (id) selected.add(String(id));
    } catch (e: any) {
        console.debug?.(e);
    }
    return selected;
}

export function setSelectedIdsDataset(gridContainer: any, selectedSet: Set<string> | unknown, activeId: string = ""): any[] {
    const list = Array.from((selectedSet as any) || []);
    const active = activeId ? String(activeId) : list[0] ? String(list[0]) : "";
    try {
        if (list.length) {
            gridContainer.dataset.mjrSelectedAssetIds = JSON.stringify(list);
            if (active) gridContainer.dataset.mjrSelectedAssetId = String(active);
            else delete gridContainer.dataset.mjrSelectedAssetId;
        } else {
            delete gridContainer.dataset.mjrSelectedAssetIds;
            delete gridContainer.dataset.mjrSelectedAssetId;
        }
    } catch (e: any) {
        console.debug?.(e);
    }
    return list;
}

export function syncSelectionClasses(gridContainer: any, selectedIds: any, getRenderedCards: (c: any) => any[]): void {
    if (!gridContainer) return;
    const set =
        selectedIds instanceof Set
            ? selectedIds
            : new Set(Array.from(selectedIds || []).map(String));
    try {
        const cards = typeof getRenderedCards === "function" ? getRenderedCards(gridContainer) : [];
        for (const card of cards) {
            const id = card?.dataset?.mjrAssetId;
            if (id && set.has(String(id))) {
                card.classList.add("is-selected");
                card.setAttribute("aria-selected", "true");
            } else {
                card.classList.remove("is-selected");
                card.setAttribute("aria-selected", "false");
            }
        }
    } catch (e: any) {
        console.debug?.(e);
    }
}

export function setSelectionIds(
    gridContainer: any,
    selectedIds: any,
    { activeId = "" }: { activeId?: string } = {},
    getRenderedCards: (c: any) => any[],
): string[] {
    if (!gridContainer) return [];
    const set = new Set<string>(
        Array.from(selectedIds || [])
            .map(String)
            .filter(Boolean),
    );
    const list = setSelectedIdsDataset(gridContainer, set, activeId);
    syncSelectionClasses(gridContainer, set, getRenderedCards);
    const selectionDetail = { selectedIds: list, activeId: activeId || list[0] || "" };
    try {
        gridContainer.dispatchEvent?.(
            new CustomEvent("mjr:selection-changed", { detail: selectionDetail }),
        );
    } catch (e: any) {
        console.debug?.(e);
    }
    // Also dispatch on window so floating overlays (MFV) can subscribe globally.
    try {
        window.dispatchEvent(new CustomEvent("mjr:selection-changed", { detail: selectionDetail }));
    } catch (e: any) {
        console.debug?.(e);
    }
    return list;
}

export function reconcileSelectionIds(
    gridContainer: any,
    visibleAssetIds: any,
    { activeId = "", emitWhenUnchanged = false }: { activeId?: string; emitWhenUnchanged?: boolean } = {},
    getRenderedCards: (c: any) => any[],
): { selectedIds: string[]; pruned: number; activeId: string } {
    if (!gridContainer) return { selectedIds: [], pruned: 0, activeId: "" };
    const visibleSet = new Set(
        Array.from(visibleAssetIds || [])
            .map(String)
            .filter(Boolean),
    );
    const current = getSelectedIdSet(gridContainer);
    const next = new Set<string>();
    let pruned = 0;
    for (const id of current) {
        if (visibleSet.has(String(id))) next.add(String(id));
        else pruned += 1;
    }
    const nextActiveId =
        activeId && next.has(String(activeId))
            ? String(activeId)
            : next.values().next().value || "";
    if (pruned === 0 && !emitWhenUnchanged) {
        syncSelectionClasses(gridContainer, next, getRenderedCards);
        setSelectedIdsDataset(gridContainer, next, nextActiveId);
        return { selectedIds: Array.from(next), pruned: 0, activeId: nextActiveId };
    }
    const selectedIds = setSelectionIds(
        gridContainer,
        next,
        { activeId: nextActiveId },
        getRenderedCards,
    );
    return { selectedIds, pruned, activeId: nextActiveId };
}

export function safeEscapeId(value: any): string {
    try {
        return CSS?.escape
            ? CSS.escape(String(value))
            : String(value).replace(/([!"#$%&'()*+,./:;<=>?@[\\\]^`{|}~])/g, "\\$1");
    } catch {
        return String(value).replace(/([!"#$%&'()*+,./:;<=>?@[\\\]^`{|}~])/g, "\\$1");
    }
}