class BSON::Document

def [](key)
  super(convert_key(key))
end

def []=(key, value)
  super(convert_key(key), convert_value(value))
end

def convert_key(key)
  key.to_bson_normalized_key
end

def convert_value(value)
  value.to_bson_normalized_value
end

def delete(key, &block)
  super(convert_key(key), &block)
end

def dig(*keys)
  super(*keys.map{|key| convert_key(key)})
end

def except(*keys)
  copy = dup
  keys.each {|key| copy.delete(key)}
  copy
end

def fetch(key, *args, &block)
  key = convert_key(key)
  super(key, *args, &block)
end

def has_key?(key)
  super(convert_key(key))
end

def has_value?(value)
  super(convert_value(value))
end

def initialize(elements = nil)
  super()
  (elements || {}).each_pair{ |key, value| self[key] = value }
end

def merge(other, &block)
  dup.merge!(other, &block)
end

def merge!(other)
  other.each_pair do |key, value|
    value = yield(convert_key(key), self[key], convert_value(value)) if block_given? && self[key]
    self[key] = value
  end
  self
end

def slice(*keys)
  keys.each_with_object(self.class.new) do |key, hash|
    if key?(key)
      hash[key] = self[key]
    end
  end
end

def symbolize_keys!
  raise ArgumentError, 'symbolize_keys! is not supported on BSON::Document instances. Please convert the document to hash first (using #to_h), then call #symbolize_keys! on the Hash instance'
end

def to_bson_normalized_value
  self
end