ruby on rails - Counting the Days from the current_level?

Question

There are 5 levels.

Each level has a certain amount of days in it that must pass before the habit can move up to the next level (as broken down by n_days):

      case n_days     
          when 0..9
            1
          when 10..24
            2
          when 25..44
            3  #Level 3
          when 45..69
            4
          when 70..99
            5
          else
            "Mastery"
         end
      end

How can we call the n_days from the present level in the habits index with something like <%= habit.current_level.n_days.count_off_from_zero_to_show %>?

For example, if we are specifically at 50 on level 3 it would show Day 5 in the habits index.

habit.rb

class Habit < ActiveRecord::Base
    belongs_to :user
    has_many :comments, as: :commentable
    has_many :levels
    serialize :committed, Array
    validates :date_started, presence: true
    before_save :current_level
    acts_as_taggable
    scope :private_submit, -> { where(private_submit: true) }
    scope :public_submit, -> { where(private_submit: false) }

attr_accessor :missed_one, :missed_two, :missed_three

    def save_with_current_level
        self.levels.build
        self.levels.build
        self.levels.build
        self.levels.build
        self.levels.build
        self.save
    end

    def self.committed_for_today
    today_name = Date::DAYNAMES[Date.today.wday].downcase
    ids = all.select { |h| h.committed.include? today_name }.map(&:id)
    where(id: ids)
  end 

    def current_level_strike
      levels[current_level - 1] # remember arrays indexes start at 0
    end

    def current_level
            return 0 unless date_started
            committed_wdays = committed.map { |day| Date::DAYNAMES.index(day.titleize) }
            n_days = ((date_started.to_date)..Date.today).count { |date| committed_wdays.include? date.wday } - self.missed_days

      case n_days     
          when 0..9
            1
          when 10..24
            2
          when 25..44
            3
          when 45..69
            4
          when 70..99
            5
          else
            "Mastery"
        end
    end
end

level.rb

class Level < ActiveRecord::Base
  belongs_to :habit
end

schema

create_table "habits", force: true do |t|
  t.integer  "missed_days",    default: 0
  t.text     "committed"
  t.integer  "days_lost",   default: 0
  t.datetime "date_started"
  t.string   "trigger"
  t.string   "target"
  t.string   "reward"
  t.boolean  "private_submit"
  t.integer  "user_id"
  t.datetime "created_at",                 null: false
  t.datetime "updated_at",                 null: false
  t.integer  "order"
end

add_index "habits", ["user_id", "created_at"], name: "index_habits_on_user_id_and_created_at"
add_index "habits", ["user_id"], name: "index_habits_on_user_id"

create_table "levels", force: true do |t|
  t.integer  "habit_id"
  t.integer  "days_lost",   default: 0
  t.integer  "missed_days",   default: 0
  t.integer  "current_level"
  t.datetime "created_at",                null: false
  t.datetime "updated_at",                null: false
end

add_index "levels", ["habit_id"], name: "index_levels_on_habit_id"

The Gist of it: https://gist.github.com/RallyWithGalli/c66dee6dfb9ab5d338c2

Answer 1

In your current_level method you've got two lines of logic that ultimately represent the value of n_days. If you want to reuse that value outside of that method or case statement, you should either store the value in an instance variable, or move the logic into another method. If the logic is only important to this class, then I might make it a private method.

class Habit < ActiveRecord::Base
  # Existing code ... 

  private

  def committed_wdays
    committed.map do |day|    
      Date::DAYNAMES.index(day.titleize)
    end
  end

  def n_days
    ((date_started.to_date)..Date.today).count do |date| 
      committed_wdays.include? date.wday
    end - self.missed_days
  end
end

The private methods can be further refined, but hopefully this gives you an idea of how you might continue to extract the shared logic.