lib/ree_lib/packages/ree_datetime/package/ree_datetime/functions/weeks_diff.rb


# frozen_string_literal: true

class ReeDatetime::WeeksDiff
  include Ree::FnDSL

  fn :weeks_diff do
    link :round_helper, from: :ree_number, import: -> { ROUND_MODES }
    link :slice, from: :ree_hash
  end

  WEEK_SECONDS = 60.0 * 60 * 24 * 7

  doc("Returns time difference in weeks (7 days range)")
  contract(
    Or[Date, DateTime, Time],
    Or[Date, DateTime, Time],
    Ksplat[
      round_mode?: Or[*ROUND_MODES]
    ] => Integer
  ).throws(ArgumentError)
  def call(start_time, end_time, **opts)
    s_delta = end_time.to_time.to_i - start_time.to_time.to_i

    raise ArgumentError, "start_time bigger than end_time" if s_delta < 0
    
    w_delta = s_delta / WEEK_SECONDS
    opts[:precision] = 0

    round_helper(
      w_delta,
      **slice(opts, [:precision, :round_mode])
    ).to_i
  end
end