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# frozen_string_literal: true
module Sass
module Value
class Number
# The {Unit} module.
module Unit
CONVERSIONS = {
# Length
'in' => {
'in' => Rational(1),
'cm' => Rational(1, 2.54),
'pc' => Rational(1, 6),
'mm' => Rational(1, 25.4),
'q' => Rational(1, 101.6),
'pt' => Rational(1, 72),
'px' => Rational(1, 96)
},
'cm' => {
'in' => Rational(2.54),
'cm' => Rational(1),
'pc' => Rational(2.54, 6),
'mm' => Rational(1, 10),
'q' => Rational(1, 40),
'pt' => Rational(2.54, 72),
'px' => Rational(2.54, 96)
},
'pc' => {
'in' => Rational(6),
'cm' => Rational(6, 2.54),
'pc' => Rational(1),
'mm' => Rational(6, 25.4),
'q' => Rational(6, 101.6),
'pt' => Rational(1, 12),
'px' => Rational(1, 16)
},
'mm' => {
'in' => Rational(25.4),
'cm' => Rational(10),
'pc' => Rational(25.4, 6),
'mm' => Rational(1),
'q' => Rational(1, 4),
'pt' => Rational(25.4, 72),
'px' => Rational(25.4, 96)
},
'q' => {
'in' => Rational(101.6),
'cm' => Rational(40),
'pc' => Rational(101.6, 6),
'mm' => Rational(4),
'q' => Rational(1),
'pt' => Rational(101.6, 72),
'px' => Rational(101.6, 96)
},
'pt' => {
'in' => Rational(72),
'cm' => Rational(72, 2.54),
'pc' => Rational(12),
'mm' => Rational(72, 25.4),
'q' => Rational(72, 101.6),
'pt' => Rational(1),
'px' => Rational(3, 4)
},
'px' => {
'in' => Rational(96),
'cm' => Rational(96, 2.54),
'pc' => Rational(16),
'mm' => Rational(96, 25.4),
'q' => Rational(96, 101.6),
'pt' => Rational(4, 3),
'px' => Rational(1)
},
# Rotation
'deg' => {
'deg' => Rational(1),
'grad' => Rational(9, 10),
'rad' => Rational(180, Math::PI),
'turn' => Rational(360)
},
'grad' => {
'deg' => Rational(10, 9),
'grad' => Rational(1),
'rad' => Rational(200, Math::PI),
'turn' => Rational(400)
},
'rad' => {
'deg' => Rational(Math::PI, 180),
'grad' => Rational(Math::PI, 200),
'rad' => Rational(1),
'turn' => Rational(Math::PI * 2)
},
'turn' => {
'deg' => Rational(1, 360),
'grad' => Rational(1, 400),
'rad' => Rational(1, Math::PI * 2),
'turn' => Rational(1)
},
# Time
's' => {
's' => Rational(1),
'ms' => Rational(1, 1000)
},
'ms' => {
's' => Rational(1000),
'ms' => Rational(1)
},
# Frequency
'Hz' => {
'Hz' => Rational(1),
'kHz' => Rational(1000)
},
'kHz' => {
'Hz' => Rational(1, 1000),
'kHz' => Rational(1)
},
# Pixel density
'dpi' => {
'dpi' => Rational(1),
'dpcm' => Rational(2.54),
'dppx' => Rational(96)
},
'dpcm' => {
'dpi' => Rational(1, 2.54),
'dpcm' => Rational(1),
'dppx' => Rational(96, 2.54)
},
'dppx' => {
'dpi' => Rational(1, 96),
'dpcm' => Rational(2.54, 96),
'dppx' => Rational(1)
}
}.freeze
UNITS_BY_TYPE = {
time: %w[s ms],
frequency: %w[Hz kHz],
'pixel density': %w[dpi dpcm dppx]
}.freeze
TYPES_BY_UNIT = UNITS_BY_TYPE.each_with_object({}) do |(key, values), hash|
values.each do |value|
hash[value] = key
end
end
module_function
def conversion_factor(unit1, unit2)
return 1 if unit1 == unit2
CONVERSIONS.dig(unit1, unit2)
end
def canonicalize_units(units)
return units if units.empty?
if units.length == 1
type = TYPES_BY_UNIT[units.first]
return type.nil? ? units : [UNITS_BY_TYPE[type].first]
end
units.map do |unit|
type = TYPES_BY_UNIT[unit]
type.nil? ? units : [UNITS_BY_TYPE[type].first]
end.sort
end
def canonical_multiplier(units)
units.reduce(1) do |multiplier, unit|
multiplier * canonical_multiplier_for_unit(unit)
end
end
def canonical_multiplier_for_unit(unit)
inner_map = CONVERSIONS[unit]
inner_map.nil? ? 1 : 1 / inner_map.values.first
end
end
private_constant :Unit
end
end
end
|
