Persist landing page query args during current session while browsing to other pages

gistfile1.txt

<script>
// Function to parse query parameters from URL
function getQueryParams(url) {
    const queryParams = {};
    const urlParams = new URLSearchParams(url.search.slice(1));
    for (const [key, value] of urlParams.entries()) {
        queryParams[key] = value;
    }
    return queryParams;
}

// Function to store query parameters in session storage
function storeQueryParamsInSessionStorage(params) {
    sessionStorage.setItem('queryParams', JSON.stringify(params));
}

// Function to retrieve query parameters from session storage
function getQueryParamsFromSessionStorage() {
    const storedParams = sessionStorage.getItem('queryParams');
    return storedParams ? JSON.parse(storedParams) : {};
}

// On page load
window.addEventListener('load', function() {
    const landingPageUrl = new URL(window.location.href);
    const queryParams = getQueryParams(landingPageUrl);
    
    // Store query parameters in session storage
    storeQueryParamsInSessionStorage(queryParams);
});

// Before navigating to other pages
document.addEventListener('click', function(event) {
    const target = event.target;
    if (target.tagName === 'A') {
        const queryParams = getQueryParamsFromSessionStorage();
        if (Object.keys(queryParams).length > 0) {
            const href = target.getAttribute('href');
            if (href && href.indexOf('?') !== -1) {
                // URL already has query parameters, merge them with session storage parameters
                const mergedParams = Object.assign({}, queryParams, getQueryParams(new URL(href)));
                target.setAttribute('href', appendQueryParams(href, mergedParams));
            } else {
                // Append session storage query parameters to the URL
                target.setAttribute('href', appendQueryParams(href || '', queryParams));
            }
        }
    }
});
</script>