How to refactor Enum.reduce?

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Hello, I have a problem with properly understanding Enum.reduce but after many tries I managed to get this inside my function to work. However, when I run mix credo --strict I see there’s a refactoring opportunity because the function body is nested too deep. Could you please help me with refactoring this function? I would appreciate an additional explanation. Thank you!

 Enum.reduce(conditions, queryable, fn {k, v}, acc -> case {k, v} do {_, ""} -> acc {_, _} when is_atom(k) -> case {k in like_fields, k in date_fields} do {true, false} -> where_ilike(acc, k, v) {false, true} -> where_date(acc, k, v) {false, false} -> where(acc, [u], field(u, ^k) == ^v) end _ -> acc end end)
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Note that the branching and pattern matching can also be applied to fn and are equivalent:

 Enum.reduce(conditions, queryable, fn {_, ""}, acc -> acc {k, v}, acc when is_atom(k) -> case {k in like_fields, k in date_fields} do {true, false} -> where_ilike(acc, k, v) {false, true} -> where_date(acc, k, v) {false, false} -> where(acc, [u], field(u, ^k) == ^v) end _, acc -> acc end)

You can also merge the first and third branches:

 Enum.reduce(conditions, queryable, fn {k, v}, acc when is_atom(k) and v != "" -> case {k in like_fields, k in date_fields} do {true, false} -> where_ilike(acc, k, v) {false, true} -> where_date(acc, k, v) {false, false} -> where(acc, [u], field(u, ^k) == ^v) end _, acc -> acc end)
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