import { createSignal } from 'solid-js';
import { appStore } from '../../store/appStore';
import type { EstimateItem } from '../../types';

export function useSelectionManager() {
    const [selectedIds, setSelectedIds] = createSignal<string[]>([]);
    const [lastSelectedId, setLastSelectedId] = createSignal<string | null>(null);

    const getVisualOrderedItems = () => {
        const { estimateItems: items, scopes, subScopes } = appStore;
        const ordered: EstimateItem[] = [];

        ordered.push(...items.filter(i => !i.scopeId));

        scopes.forEach(scope => {
            ordered.push(...items.filter(i => i.scopeId === scope.id && !i.subScopeId));
            subScopes.filter(ss => ss.scopeId === scope.id).forEach(ss => {
                ordered.push(...items.filter(i => i.subScopeId === ss.id));
            });
        });

        return ordered;
    };

    const toggleSelection = (id: string, isMulti: boolean, isShift: boolean = false) => {
        if (isShift && lastSelectedId()) {
            const orderedItems = getVisualOrderedItems();
            const lastIdx = orderedItems.findIndex(i => i.id === lastSelectedId());
            const currentIdx = orderedItems.findIndex(i => i.id === id);

            if (lastIdx !== -1 && currentIdx !== -1) {
                const start = Math.min(lastIdx, currentIdx);
                const end = Math.max(lastIdx, currentIdx);
                const rangeIds = orderedItems.slice(start, end + 1).map(i => i.id);

                setSelectedIds(prev => {
                    const newSet = new Set(prev);
                    rangeIds.forEach(rid => newSet.add(rid));
                    return Array.from(newSet);
                });
            }
        } else if (isMulti) {
            setSelectedIds(prev => prev.includes(id)
                ? prev.filter(i => i !== id)
                : [...prev, id]
            );
        } else {
            if (selectedIds().includes(id) && selectedIds().length === 1) {
                setSelectedIds([]);
            } else {
                setSelectedIds([id]);
            }
        }
        setLastSelectedId(id);
    };

    const clearSelection = (e?: MouseEvent) => {
        if (!e || e.target === e.currentTarget) {
            setSelectedIds([]);
            setLastSelectedId(null);
        }
    };

    const copyColumnSum = (column: 'quantity'|'unitPrice'|'subtotal'|'markup'|'contingency'|'total', val: number, setCopyToast: (msg: string | null) => void) => {
        navigator.clipboard.writeText(String(val)).then(() => {
            const labels: Record<string, string> = {
                quantity: 'Qty', unitPrice: 'Price', subtotal: 'Subtotal',
                markup: 'Markup', contingency: 'Contingency', total: 'Total'
            };
            setCopyToast(`Copied ${labels[column]}: ${val}`);
            setTimeout(() => setCopyToast(null), 2500);
        });
    };

    return { selectedIds, setSelectedIds, lastSelectedId, setLastSelectedId, toggleSelection, clearSelection, copyColumnSum };
}