class NumericWithUnit

# File lib/numeric_with_unit.rb, line 10
def initialize(value, unit)
  @value = value
  @unit = unit.is_a?(Unit) ? unit : Unit[unit]
end

# File lib/numeric_with_unit.rb, line 103
def *(other)
  case other
  when self.class
    multiply_with_other_unit(other)
  else
    self.class.new(@value*other, @unit)
  end
end

# File lib/numeric_with_unit.rb, line 129
def **(num)
  # Dimension Check
  if @unit.derivation.all?{|k,v| o = v * num; o.to_i == o} # TODO: 整数かどうかの判定方法いいのこれで
   self.class.new(@value**num, @unit**num)
  else
    nu = @unit.simplify
    if nu.derivation.all?{|k,v| o = v * num; o.to_i == o}
      nv = nu.from_si(@unit.to_si(@value))
      self.class.new(nv ** num, nu**num)
    else
      raise DimensionError, "All derivating units order multiplied #{num} must be integer"
    end
 end
end

# File lib/numeric_with_unit.rb, line 90
def +(other)
  nwu = if other.is_a? self.class
    other
  else
    self.class.new(other, Unit.new)
  end
  add_with_other_unit(nwu)
end

# File lib/numeric_with_unit.rb, line 82
def +@
  self
end

# File lib/numeric_with_unit.rb, line 99
def -(other)
  self + (-other)
end

# File lib/numeric_with_unit.rb, line 86
def -@
  self.class.new(-@value, @unit)
end

# File lib/numeric_with_unit.rb, line 112
def /(other)
  case other
  when self.class
    devide_with_other_unit(other)
  else
    self.class.new(@value/other, @unit)
  end
end

# File lib/numeric_with_unit.rb, line 27
def <=>(other)
  if other.is_a?(self.class) and @unit.dimension_equal? other.unit
    value_si <=> other.value_si
  end
end

# File lib/numeric_with_unit.rb, line 33
def ===(other)
  self.<=>(other) == 0
end

# File lib/numeric_with_unit.rb, line 148
def cbrt; root(3) end

# File lib/numeric_with_unit.rb, line 150
def ceil
  self.class.new(@value.ceil, @unit)
end

# File lib/numeric_with_unit.rb, line 121
def coerce(other)
  if other.is_a?(self.class)
    [other, self]
  else
    [self.class.new(other, Unit.new), self]
  end
end

# File lib/numeric_with_unit.rb, line 71
def convert(unit)
  clone.convert!(unit)
end

# File lib/numeric_with_unit.rb, line 58
def convert!(unit)
  new_unit = unit.is_a?(Unit) ? unit : Unit[unit]

  unless @unit.dimension_equal? new_unit
    raise DimensionError, "Dimensions are different between #{@unit.symbol}#{@unit.dimension} #{new_unit.symbol}#{new_unit.dimension}"
  end

  new_value = new_unit.from_si(@unit.to_si(@value))
  @value, @unit = new_value, new_unit
  self
end

# File lib/numeric_with_unit.rb, line 154
def floor
  self.class.new(@value.floor, @unit)
end

# File lib/numeric_with_unit.rb, line 16
def inspect
  "#{@value.inspect} [#{@unit.symbol}] #{@unit.dimension.inspect}"
end

# File lib/numeric_with_unit/util2.rb, line 10
def method_missing(name, *args)
  if args.empty?
    unit_str = name.to_s.gsub('_', '/')
    resolve_unit_chain(Unit[unit_str])
  else
    raise Unit::NoUnitError
  end
rescue Unit::NoUnitError
  super
end

# File lib/numeric_with_unit.rb, line 144
def root(num)
  self**(Rational(1,num))
end

# File lib/numeric_with_unit.rb, line 158
def round
  self.class.new(@value.round, @unit)
end

# File lib/numeric_with_unit.rb, line 77
def simplify
  convert(@unit.simplify)
end

# File lib/numeric_with_unit.rb, line 147
def sqrt; root(2) end

# File lib/numeric_with_unit.rb, line 38
def succ
  self.class.new(@value.succ, @unit)
end

# File lib/numeric_with_unit.rb, line 48
def to_f
  @value.to_f
end

# File lib/numeric_with_unit.rb, line 43
def to_i
  @value.to_i
end

# File lib/numeric_with_unit.rb, line 21
def to_s
  "#{@value.to_s} #{@unit.symbol}"
end

# File lib/numeric_with_unit.rb, line 162
def truncate
  self.class.new(@value.truncate, @unit)
end

# File lib/numeric_with_unit.rb, line 53
def value_si
  @unit.to_si(@value)
end

# File lib/numeric_with_unit.rb, line 169
def add_with_other_unit(other)
  if @unit.dimension_equal? other.unit
    v1 = @unit.to_si(@value)
    v2 = other.unit.to_si(other.value)
    vr = @unit.from_si(v1+v2)
    self.class.new(vr, @unit)
  else
    raise DimensionError, "Dimensions are different between #{@unit.dimension} #{other.unit.dimension}"
  end
end

# File lib/numeric_with_unit.rb, line 191
def adjust_other_unit(other)
  if @unit.derivation.any?{|k,v| k == other.unit} # [L/min]*[min]などのケース
    other
  elsif h = @unit.derivation.find{|k,v| k.dimension_equal? other.unit} # [L/min]*[s]などのケース
    other[ h.first ]
  elsif @unit.dimension_equal? other.unit # [mm]*[cm]などのケース
    other[@unit]
  else
    other
  end
end

# File lib/numeric_with_unit.rb, line 185
def devide_with_other_unit(other)
  onwu = adjust_other_unit(other)
  self.class.new(@value / onwu.value, @unit / onwu.unit)
end

# File lib/numeric_with_unit.rb, line 180
def multiply_with_other_unit(other)
  onwu = adjust_other_unit(other)
  self.class.new(@value * onwu.value, @unit * onwu.unit)
end

# File lib/numeric_with_unit/util2.rb, line 25
def resolve_unit_chain(unit)
  unit_chain = @unit_chain || []
  unit_chain.map!{|nwu, chained_unit| [nwu, chained_unit * unit]}
  unit_chain << [self, unit]
  
  if i = unit_chain.index{|nwu, chained_unit| nwu.unit.dimension_equal? chained_unit}
    nwu, chained_unit = *unit_chain[i]
    nwu.convert(chained_unit)
  else
    newnwu = self.class.new(@value, @unit*unit)
    newnwu.unit_chain = unit_chain
    newnwu
  end
end