Set multiple entries from different categories merge or join?

Question

So I'm using cookies to determine what entries I want to display on some specific pages. I have a lot of different cookies which will change which entries I should be displaying. I currently have around 12 different cookies so would end up with over a thoasad different possiblities. Here is an example if a person has a both the below cookies, they should see entries from all of the below sets so I would need to either merge or join these if that specific cookie was found and the entries for that match were set.

{% if getCookie('cookie1') %}
{% set cookie1Entries = craft.categories.group('resource').slug('slug1') %}
{% set cookie1Entries2 = craft.categories.group('resource').slug('slug2') %}
{% set cookie1Entries3 = craft.categories.group('resource').slug('slug3') %}

{% set entriescookie1 = craft.entries({
    group: 'resource',
    relatedTo: [
        'and',
        { targetElement: cookie1Entries },
        { targetElement: cookie1Entries2 },
        { targetElement: cookie1Entries3 }
    ]
}).limit(3).find() %}
{% endif %}

{% if getCookie('cookie2') %}
{% set cookie2Entries = craft.categories.group('resource').slug('slug4') %}
{% set cookie2Entries2 = craft.categories.group('resource').slug('slug5') %}
{% set cookie2Entries3 = craft.categories.group('resource').slug('slug6') %}

{% set entriescookie2 = craft.entries({
    group: 'resource',
    relatedTo: [
        'and',
        { targetElement: cookie2Entries },
        { targetElement: cookie2Entries2 },
        { targetElement: cookie2Entries3 }
    ]
}).limit(3).find() %}
{% endif %}

What would be the best way to merge all of these at the end of checking for cookies, and also prevent from showing duplicate entries? Not sure how I would go about joining or merging these entries, as I would need to check if entriescookie1 or entriescookie2 was also set.

Answer 1

Use Craft's indexBy and index them by ID. If then you use Twig's merge function the duplicates will be removed and everything will be available in one array.

And may I suggest that if you're going to have a lot of logics in your templates, you'd better move this to a plugin and rewrite it in PHP. Templates should mostly be about templating, not about logics.