JSONB Data Type Modification in Postgresql-CodePudding

I have a doubt with modification of jsonb data type in postgres

Basic setup:-

array=> ["1", "2", "3"]
and now I have a postgresql database with an id column and a jsonb datatype column named lets just say cards.

  id    cards
----- ---------
1       {"1": 3, "4": 2}

thats the data in the table named test

Question:

How do I convert the cards of id->1 FROM {"1": 3, "4": 2} TO {"1": 4, "4":2, "2": 1, "3": 1}

How I expect the changes to occur:

From the array, increment by 1 all elements present inside the array that exist in the cards jsonb as a key thus changing {"1": 3} to {"1": 4} and insert the values that don't exist as a key in the cards jsonb with a value of 1 thus changing {"1":4, "4":2} to {"1":4, "4":2, "2":1, "3":1} purely through postgres.

Partial Solution

I asked a senior for support regarding my question and I was told this:-

Roughly (names may differ): object keys to explode cards, array_elements to explode the array, left join them, do the calculation, re-aggregate the object. There may be a more direct way to do this but the above brute-force approach will work.

So I tried to follow through it using these two functions json_each_text(), json_array_elements_text() but ended up stuck halfway into this as well as I was unable to understand what they meant by left joining two columns:-

SELECT jsonb_each_text(tester_cards) AS each_text, jsonb_array_elements_text('[["1", 1], ["2", 1], ["3", 1]]') AS array_elements FROM tester WHERE id=1;

TLDR;

Update statement that checks whether a range of keys from an array exist or not in the jsonb data and automatically increments by 1 or inserts respectively the keys into the jsonb with a value of 1

Now it might look like I'm asking to be spoonfed but I really haven't managed to find anyway to solve it so any assistance would be highly appreciated