David Underwood
49 lines
755 B
Ruby
49 lines
755 B
Ruby
class Checkout
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class InvalidItem < StandardError; end
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AVAILABLE_ITEMS = {
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PI5: 60.00,
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ZERO2W: 15.00,
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PICO2: 4.00
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}
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def initialize
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@items = []
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end
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def add(item)
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raise InvalidItem unless valid_item?(item)
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@items.push item
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end
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def items
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@items
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end
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def total
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pre_discount_total - current_discount
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end
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private
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def valid_item?(item)
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return AVAILABLE_ITEMS.keys.include?(item)
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end
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def current_discount
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# BOGOF ZERO2W
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discount = (@items.count(:ZERO2W) / 2.0).floor * AVAILABLE_ITEMS[:ZERO2W]
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# TODO: Bulk PICO2
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return discount
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end
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def pre_discount_total
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@items.reduce(0.00) do |running_total, item|
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running_total + AVAILABLE_ITEMS[item]
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end
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end
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end
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