TARGET_TOTAL = { :common => 200, :rare => 140, :epic => 100, :legendary => 30 }
CARDS_BY_RARITY = { :common => 100, :rare => 70, :epic => 50, :legendary => 30 }
RARITY_CHANCE = { :legendary => 0.005, :epic => 0.025, :rare => 0.1, :common => 1 }
RARITY_PRIORITY_CHECK = [ :legendary, :epic, :rare, :common ]
DISENCHANTED_ARCANE_DUST = { :common => 2, :rare => 10, :epic => 100, :legendary => 400 }
CRAFT_ARCANE_DUST = { :legendary => 1600, :epic => 400, :rare => 100, :common => 10 }
CRAFT_RARITY_PRIORITY = [ :legendary, :epic, :rare, :common ]
CARDS_PER_PACK = 5

class Card
  attr_accessor :rarity, :number
  def initialize(rarity, number)
    @rarity = rarity
    @number = number
  end
end

class PackGenerator
  
  def initialize
    @collection = { :common => [], :rare => [], :epic => [], :legendary => [] }
    @arcane_dust = 0
    @packs_open = 0
    @disenchanted = 0
  end

  def check_packs_needed
    while !is_collection_complete?
      add_collection(random_pack)
      @packs_open += 1
      #puts info
    end
    
    return @packs_open
  end

  def add_collection(pack)
    pack.each do |card|
      unless is_card_number_already_in_collection?(card.rarity, card.number)
        @collection[card.rarity] << card
      else
        disenchant_card(card)
      end
    end
  end

  def disenchant_card(card)
    @arcane_dust += DISENCHANTED_ARCANE_DUST[card.rarity]
    @disenchanted += 1

    CRAFT_RARITY_PRIORITY.each do |rarity|
      if @collection[rarity].size != TARGET_TOTAL[rarity]
        craft_card(rarity) if CRAFT_ARCANE_DUST[rarity] <= @arcane_dust
        break
      end
    end
  end

  def craft_card(rarity)
    (1..CARDS_BY_RARITY[rarity]).each do |i|
      unless is_card_number_already_in_collection?(rarity, i)
        @arcane_dust -= CRAFT_ARCANE_DUST[rarity]
        @collection[rarity] << Card.new(rarity, i)
        return
      end
    end
  end

  def is_card_number_already_in_collection?(rarity, i)
    target_total = rarity == :legendary ? 1 : 2
    return @collection[rarity].select { |card| card.number == i }.size == target_total   
  end
  
  def random_pack
    @last_pack = []
    (1..5).each do |i|
      @last_pack << random_rarity_card((i == 5 && !@last_pack.any? { |card| card.rarity != :common }))
      #@last_pack << random_rarity_card(i == 1)
    end
    return @last_pack
  end

  def random_rarity_card(force_rare)
    r = rand # get rarity

    card = nil
    RARITY_PRIORITY_CHECK.each do |rarity|
      chance = force_rare && rarity == :rare ? 1 : RARITY_CHANCE[rarity]
      if r < chance
        card = Card.new(rarity, random_card_from_rarity(CARDS_BY_RARITY[rarity]))
        break
      end
    end

    return card
  end

  def random_card_from_rarity(max)
    return (rand * (max - 1) + 1).round
  end

  def is_collection_complete?
    @collection.each do |rarity, list|
      return false if list.size != TARGET_TOTAL[rarity]
    end
    return true
  end

  def info
    msg = ""
    msg << "#{@packs_open}\t"
    msg << "#{@last_pack.collect { |c| c.rarity }.inspect}\t"
    msg << "#{@collection[:common].size}\t"
    msg << "#{@collection[:rare].size}\t"
    msg << "#{@collection[:epic].size}\t"
    msg << "#{@collection[:legendary].size}\t"
    msg << "#{@disenchanted}\t"
    msg << "#{@arcane_dust}"
    return msg
  end
end

#STDOUT.reopen(File.open('generator.log', 'w+'))

results = []
(1..500).each do |i|
  p = PackGenerator.new
  results << p.check_packs_needed
  puts "[#{i}] Packs needed: #{results[i-1]}."
end
puts "Average: #{results.inject{|sum,x| sum + x} / results.size}"
puts "Max: #{results.max}"
puts "Min: #{results.min}"