module Eulim
  module Chemistry
    # This class has functionality for elements
    # Ex: symbol, atomic mass, atomic number
    class Element
      VALID_SYMBOL_REGEXP = /[A-Z][a-z]{0,2}/
      VALID_NAME_REGEXP = /[A-Z][a-z]+/

      attr_accessor :atomic_mass, :symbol, :name, :atomic_number

      @@attrs = %w[symbol name atomic_number atomic_mass]

      def initialize(args)
        return nil unless args
        args.each do |k, v|
          instance_variable_set("@#{k}", v) unless v.nil?
        end
      end

      # Data taken from 'www.science.co.il/elements/'
      @@elements = [
        { symbol: 'H',   name: 'Hydrogen',
          atomic_number: 1, atomic_mass: 1.0079 },
        { symbol: 'He',  name: 'Helium',
          atomic_number: 2, atomic_mass: 4.002602 },
        { symbol: 'Li',  name: 'Lithium',
          atomic_number: 3, atomic_mass: 6.941 },
        { symbol: 'Be',  name: 'Beryllium',
          atomic_number: 4, atomic_mass: 9.012182 },
        { symbol: 'B',   name: 'Boron',
          atomic_number: 5, atomic_mass: 10.811 },
        { symbol: 'C',   name: 'Carbon',
          atomic_number: 6, atomic_mass: 12.0107 },
        { symbol: 'N',   name: 'Nitrogen',
          atomic_number: 7, atomic_mass: 14.0067 },
        { symbol: 'O',   name: 'Oxygen',
          atomic_number: 8, atomic_mass: 15.9996 },
        { symbol: 'F',   name: 'Fluorine',
          atomic_number: 9, atomic_mass: 18.9984 },
        { symbol: 'Ne',  name: 'Neon',
          atomic_number: 10,  atomic_mass: 20.1797 },
        { symbol: 'Na',  name: 'Sodium',
          atomic_number: 11,  atomic_mass: 22.9897 },
        { symbol: 'Mg',  name: 'Magnesium',
          atomic_number: 12,  atomic_mass: 24.305 },
        { symbol: 'Al',  name: 'Aluminium',
          atomic_number: 13,  atomic_mass: 26.9815 },
        { symbol: 'Si',  name: 'Silicon',
          atomic_number: 14,  atomic_mass: 28.0855 },
        { symbol: 'P',   name: 'Phosphorus',
          atomic_number: 15,  atomic_mass: 30.9738 },
        { symbol: 'S',   name: 'Sulfur',
          atomic_number: 16,  atomic_mass: 32.065 },
        { symbol: 'Cl',  name: 'Chlorine',
          atomic_number: 17,  atomic_mass: 35.453 },
        { symbol: 'Ar',  name: 'Argon',
          atomic_number: 18,  atomic_mass: 39.948 },
        { symbol: 'K',   name: 'Potassium',
          atomic_number: 19,  atomic_mass: 39.0983 },
        { symbol: 'Ca',  name: 'Calcium',
          atomic_number: 20,  atomic_mass: 40.078 },
        { symbol: 'Sc',  name: 'Scandium',
          atomic_number: 21,  atomic_mass: 44.9559 },
        { symbol: 'Ti',  name: 'Titanium',
          atomic_number: 22,  atomic_mass: 47.867 },
        { symbol: 'V',   name: 'Vanadium',
          atomic_number: 23,  atomic_mass: 50.9415 },
        { symbol: 'Cr',  name: 'Chromium',
          atomic_number: 24,  atomic_mass: 51.9961 },
        { symbol: 'Mn',  name: 'Manganese',
          atomic_number: 25,  atomic_mass: 54.938 },
        { symbol: 'Fe',  name: 'Iron',
          atomic_number: 26,  atomic_mass: 55.845 },
        { symbol: 'Co',  name: 'Cobalt',
          atomic_number: 27,  atomic_mass: 58.9332 },
        { symbol: 'Ni',  name: 'Nickel',
          atomic_number: 28,  atomic_mass: 58.6934 },
        { symbol: 'Cu',  name: 'Copper',
          atomic_number: 29,  atomic_mass: 63.546 },
        { symbol: 'Zn',  name: 'Zinc',
          atomic_number: 30,  atomic_mass: 65.39 },
        { symbol: 'Ga',  name: 'Gallium',
          atomic_number: 31,  atomic_mass: 69.723 },
        { symbol: 'Ge',  name: 'Germanium',
          atomic_number: 32,  atomic_mass: 72.64 },
        { symbol: 'As',  name: 'Arsenic',
          atomic_number: 33,  atomic_mass: 74.9216 },
        { symbol: 'Se',  name: 'Selenium',
          atomic_number: 34,  atomic_mass: 78.96 },
        { symbol: 'Br',  name: 'Bromine',
          atomic_number: 35,  atomic_mass: 79.904 },
        { symbol: 'Kr',  name: 'Krypton',
          atomic_number: 36,  atomic_mass: 83.3 },
        { symbol: 'Rb',  name: 'Rubidium',
          atomic_number: 37,  atomic_mass: 85.4678 },
        { symbol: 'Sr',  name: 'Strontium',
          atomic_number: 38,  atomic_mass: 87.62 },
        { symbol: 'Y',   name: 'Yttrium',
          atomic_number: 39,  atomic_mass: 88.9059 },
        { symbol: 'Zr',  name: 'Zirconium',
          atomic_number: 40,  atomic_mass: 91.224 },
        { symbol: 'Nb',  name: 'Niobium',
          atomic_number: 41,  atomic_mass: 92.9064 },
        { symbol: 'Mo',  name: 'Molybdenum',
          atomic_number: 42,  atomic_mass: 95.94 },
        { symbol: 'Tc',  name: 'Technitium',
          atomic_number: 43,  atomic_mass: 98 },
        { symbol: 'Ru',  name: 'Ruthenium',
          atomic_number: 44,  atomic_mass: 101.07 },
        { symbol: 'Rh',  name: 'Rhodium',
          atomic_number: 45,  atomic_mass: 102.9055 },
        { symbol: 'Pd',  name: 'Palladium',
          atomic_number: 46,  atomic_mass: 106.42 },
        { symbol: 'Ag',  name: 'Silver',
          atomic_number: 47,  atomic_mass: 107.8682 },
        { symbol: 'Cd',  name: 'Cadmiuim',
          atomic_number: 48,  atomic_mass: 112.411 },
        { symbol: 'In',  name: 'Indium',
          atomic_number: 49,  atomic_mass: 114.818 },
        { symbol: 'Sn',  name: 'Tin',
          atomic_number: 50,  atomic_mass: 118.71 },
        { symbol: 'Sb',  name: 'Antimony',
          atomic_number: 51,  atomic_mass: 121.76 },
        { symbol: 'Te',  name: 'Tellurium',
          atomic_number: 52,  atomic_mass: 127.6 },
        { symbol: 'I',   name: 'Iodine',
          atomic_number: 53,  atomic_mass: 126.9045 },
        { symbol: 'Xe',  name: 'Xenon',
          atomic_number: 54,  atomic_mass: 131.293 },
        { symbol: 'Cs',  name: 'Cesium',
          atomic_number: 55,  atomic_mass: 132.9055 },
        { symbol: 'Ba',  name: 'Barium',
          atomic_number: 56,  atomic_mass: 137.327 },
        { symbol: 'La',  name: 'Lanthanum',
          atomic_number: 57,  atomic_mass: 138.9055 },
        { symbol: 'Ce',  name: 'Cerium',
          atomic_number: 58,  atomic_mass: 140.116 },
        { symbol: 'Pr',  name: 'Praseodymium',
          atomic_number: 59,  atomic_mass: 140.9077 },
        { symbol: 'Nd',  name: 'Neodymium',
          atomic_number: 60,  atomic_mass: 144.24 },
        { symbol: 'Pm',  name: 'Promethium',
          atomic_number: 61,  atomic_mass: 145 },
        { symbol: 'Sm',  name: 'Samarium',
          atomic_number: 62,  atomic_mass: 150.36 },
        { symbol: 'Eu',  name: 'Europium',
          atomic_number: 63,  atomic_mass: 151.964 },
        { symbol: 'Gd',  name: 'Gadolium',
          atomic_number: 64,  atomic_mass: 157.25 },
        { symbol: 'Tb',  name: 'Terbium',
          atomic_number: 65,  atomic_mass: 158.9253 },
        { symbol: 'Dy',  name: 'Dysprosium',
          atomic_number: 66,  atomic_mass: 162.5 },
        { symbol: 'Ho',  name: 'Holmium',
          atomic_number: 67,  atomic_mass: 164.9303 },
        { symbol: 'Er',  name: 'Erbium',
          atomic_number: 68,  atomic_mass: 167.259 },
        { symbol: 'Tm',  name: 'Thulium',
          atomic_number: 69,  atomic_mass: 168.9342 },
        { symbol: 'Yb',  name: 'Ytterbium',
          atomic_number: 70,  atomic_mass: 173.04 },
        { symbol: 'Lu',  name: 'Lutetium',
          atomic_number: 71,  atomic_mass: 174.967 },
        { symbol: 'Hf',  name: 'Hafnium',
          atomic_number: 72,  atomic_mass: 178.49 },
        { symbol: 'Ta',  name: 'Tantalum',
          atomic_number: 73,  atomic_mass: 180.9479 },
        { symbol: 'W',   name: 'Tungsten',
          atomic_number: 74,  atomic_mass: 183.84 },
        { symbol: 'Re',  name: 'Rhenium',
          atomic_number: 75,  atomic_mass: 186.207 },
        { symbol: 'Os',  name: 'Osmium',
          atomic_number: 76,  atomic_mass: 190.23 },
        { symbol: 'Ir',  name: 'Iridium',
          atomic_number: 77,  atomic_mass: 192.217 },
        { symbol: 'Pt',  name: 'Platinum',
          atomic_number: 78,  atomic_mass: 195.078 },
        { symbol: 'Au',  name: 'Gold',
          atomic_number: 79,  atomic_mass: 196.9665 },
        { symbol: 'Hg',  name: 'Mercury',
          atomic_number: 80,  atomic_mass: 200.59 },
        { symbol: 'Tl',  name: 'Thallium',
          atomic_number: 81,  atomic_mass: 204.3833 },
        { symbol: 'Pb',  name: 'Lead',
          atomic_number: 82,  atomic_mass: 207.2 },
        { symbol: 'Bi',  name: 'Bismuth',
          atomic_number: 83,  atomic_mass: 208.9804 },
        { symbol: 'Po',  name: 'Polonium',
          atomic_number: 84,  atomic_mass: 209 },
        { symbol: 'At',  name: 'Astatine',
          atomic_number: 85,  atomic_mass: 210 },
        { symbol: 'Rn',  name: 'Radon',
          atomic_number: 86,  atomic_mass: 222 },
        { symbol: 'Fr',  name: 'Francium',
          atomic_number: 87,  atomic_mass: 223 },
        { symbol: 'Ra',  name: 'Radium',
          atomic_number: 88,  atomic_mass: 226 },
        { symbol: 'Ac',  name: 'Actinium',
          atomic_number: 89,  atomic_mass: 227 },
        { symbol: 'Th',  name: 'Thorium',
          atomic_number: 90,  atomic_mass: 232.0381 },
        { symbol: 'Pa',  name: 'Protactinium',
          atomic_number: 91,  atomic_mass: 231.0359 },
        { symbol: 'U',   name: 'Uranium',
          atomic_number: 92,  atomic_mass: 238.0289 },
        { symbol: 'Np',  name: 'Neptunum',
          atomic_number: 93,  atomic_mass: 237 },
        { symbol: 'Pu',  name: 'Plutonium',
          atomic_number: 94,  atomic_mass: 244 },
        { symbol: 'Am',  name: 'Americium',
          atomic_number: 95,  atomic_mass: 243 },
        { symbol: 'Cm',  name: 'Curium',
          atomic_number: 96,  atomic_mass: 247 },
        { symbol: 'Bk',  name: 'Berkilium',
          atomic_number: 97,  atomic_mass: 247 },
        { symbol: 'Cf',  name: 'Californium',
          atomic_number: 98,  atomic_mass: 251 },
        { symbol: 'Es',  name: 'Einsteinium',
          atomic_number: 99,  atomic_mass: 252 },
        { symbol: 'Fm',  name: 'Fermium',
          atomic_number: 100,  atomic_mass: 257 },
        { symbol: 'Md',  name: 'Mendelevium',
          atomic_number: 101,  atomic_mass: 258 },
        { symbol: 'No',  name: 'Nobelium',
          atomic_number: 102,  atomic_mass: 259 },
        { symbol: 'Lr',  name: 'Lawrencium',
          atomic_number: 103,  atomic_mass: 262 },
        { symbol: 'Rf',  name: 'Rutherfordium',
          atomic_number: 104,  atomic_mass: 261 },
        { symbol: 'Db',  name: 'Dubnium',
          atomic_number: 105,  atomic_mass: 262 },
        { symbol: 'Sg',  name: 'Seaborgium',
          atomic_number: 106,  atomic_mass: 266 },
        { symbol: 'Bh',  name: 'Bohrium',
          atomic_number: 107,  atomic_mass: 264 },
        { symbol: 'Hs',  name: 'Hassium',
          atomic_number: 108,  atomic_mass: 277 },
        { symbol: 'Mt',  name: 'Meitnerium',
          atomic_number: 109,  atomic_mass: 268 }
      ]

      private_class_method def self.method_missing(m, *args)
        attribute = m.to_s.split('get_by_').last
        valid_method? m, attribute
        args[0] = attribute == 'name' ? args[0].capitalize : args[0]
        element_data = get_element_by_attribute attribute, args[0]
        raise 'Element not found' unless element_data
        new(element_data)
      end

      private_class_method def self.get_element_by_attribute(attribute, value)
        @@elements.select do |element|
          element[attribute.to_sym] == value
        end.first
      end

      private_class_method def self.valid_method?(m, attribute)
        super unless m.to_s.start_with?('get_by_')
        raise(NameError, 'Invalid attribute') unless @@attrs.include? attribute
      end

      private_class_method :new
    end
  end
end