const DRAFT_PREFIX = 'restock-draft';

export type RestockDraftData = {
    stockType: 'good' | 'reject';
    selectedProductId: string;
    quantities: Record<string, number>;
    notes: string;
    photo?: string;
};

function getKey(type: 'create' | 'edit', userId?: number): string {
    if (type === 'edit') {
        return `${DRAFT_PREFIX}-edit-${userId ?? 'anon'}`;
    }

    return `${DRAFT_PREFIX}-create-${userId ?? 'anon'}`;
}

export function saveRestockDraft(
    type: 'create' | 'edit',
    data: RestockDraftData,
    userId?: number,
): boolean {
    if (type !== 'create') {
        return false;
    }

    try {
        const key = getKey(type, userId);
        localStorage.setItem(key, JSON.stringify(data));

        return true;
    } catch {
        return false;
    }
}

export function loadRestockDraft(
    type: 'create' | 'edit',
    userId?: number,
): RestockDraftData | null {
    try {
        const key = getKey(type, userId);
        const raw = localStorage.getItem(key);

        if (!raw) {
            return null;
        }

        return JSON.parse(raw) as RestockDraftData;

    } catch {
        return null;
    }
}

export function clearRestockDraft(
    type: 'create' | 'edit',
    userId?: number,
): void {
    try {
        const key = getKey(type, userId);
        localStorage.removeItem(key);
    } catch {
        // ignore
    }
}