# encoding: UTF-8

module Stringex
  module Localization
    module ConversionExpressions
      ABBREVIATION = /(\s|^)([[:alpha:]](\.[[:alpha:]])+(\.?)[[:alpha:]]*(\s|$))/

      ACCENTED_HTML_ENTITY = /&([A-Za-z])(grave|acute|circ|tilde|uml|ring|cedil|slash);/

      APOSTROPHE = /(^|[[:alpha:]])'|`([[:alpha:]]|$)/

      CHARACTERS =  {
        :and           => /\s*&\s*/,
        :at            => /\s*@\s*/,
        :degrees       => /\s*°\s*/,
        :divide        => /\s*÷\s*/,
        :dot           => /(\S|^)\.(\S)/,
        :ellipsis      => /\s*\.{3,}\s*/,
        :equals        => /\s*=\s*/,
        :number        => /\s*#/,
        :percent       => /\s*%\s*/,
        :plus          => /\s*\+\s*/,
        :slash         => /\s*(\\|\/|／)\s*/,
        :star          => /\s*\*\s*/,
      }

      # Things that just get converted to spaces
      CLEANUP_CHARACTERS = /[\.,:;(){}\[\]\?!\^'ʼ"_\|]/
      CLEANUP_HTML_ENTITIES = /&[^;]+;/

      CURRENCIES_SUPPORTED_SIMPLE = {
        :dollars => /\$/,
        :euros   => /€/,
        :pounds  => /£/,
        :yen     => /¥/,
        :reais   => /R$/
      }
      CURRENCIES_SUPPORTED_COMPLEX = {
        :dollars => :dollars_cents,
        :euros   => :euros_cents,
        :pounds  => :pounds_pence,
        :reais   => :reais_cents
      }
      CURRENCIES_SUPPORTED = Regexp.new(CURRENCIES_SUPPORTED_SIMPLE.values.join('|'))
      CURRENCIES_SIMPLE = CURRENCIES_SUPPORTED_SIMPLE.inject({}) do |hash, content|
        key, expression = content
        hash[key] = /(?:\s|^)#{expression}(\d*)(?:\s|$)/
        hash
      end
      CURRENCIES_COMPLEX = CURRENCIES_SUPPORTED_SIMPLE.inject({}) do |hash, content|
        key, expression = content
        # Do we really need to not worry about complex currencies if there are none for the currency?
        complex_key = CURRENCIES_SUPPORTED_COMPLEX[key]
        if complex_key
          hash[complex_key] = /(?:\s|^)#{expression}(\d+)\.(\d+)(?:\s|$)/
        end
        hash
      end
      CURRENCIES = CURRENCIES_SIMPLE.merge(CURRENCIES_COMPLEX)

      HTML_ENTITIES = Proc.new(){
        base = {
          :amp          => %w{#38 amp},
          :cent         => %w{#162 cent},
          :copy         => %w{#169 copy},
          :deg          => %w{#176 deg},
          :divide       => %w{#247 divide},
          :double_quote => %w{#34 #822[012] quot ldquo rdquo dbquo},
          :ellipsis     => %w{#8230 hellip},
          :en_dash      => %w{#8211 ndash},
          :em_dash      => %w{#8212 mdash},
          :frac14       => %w{#188 frac14},
          :frac12       => %w{#189 frac12},
          :frac34       => %w{#190 frac34},
          :gt           => %w{#62 gt},
          :lt           => %w{#60 lt},
          :nbsp         => %w{#160 nbsp},
          :pound        => %w{#163 pound},
          :reg          => %w{#174 reg},
          :single_quote => %w{#39 #821[678] apos lsquo rsquo sbquo},
          :times        => %w{#215 times},
          :trade        => %w{#8482 trade},
          :yen          => %w{#165 yen},
        }
        base.inject({}) do |hash, content|
          key, expression = content
          hash[key] = /&(#{expression.join('|')});/
          hash
        end
      }.call

      HTML_TAG = Proc.new(){
        name = /[\w:_-]+/
        value = /([A-Za-z0-9]+|('[^']*?'|"[^"]*?"))/
        attr = /(#{name}(\s*=\s*#{value})?)/
        /<[!\/?\[]?(#{name}|--)(\s+(#{attr}(\s+#{attr})*))?\s*([!\/?\]]+|--)?>/
      }.call

      SMART_PUNCTUATION = {
        /(“|”|\302\223|\302\224|\303\222|\303\223)/ => '"',
        /(‘|’|\302\221|\302\222|\303\225)/ => "'",
        /…/ => "...",
      }

      # Ordered by denominator then numerator of the value
      VULGAR_FRACTIONS = {
        :half          => /(&#189;|&frac12;|½)/,
        :one_third     => /(&#8531;|⅓)/,
        :two_thirds    => /(&#8532;|⅔)/,
        :one_fourth    => /(&#188;|&frac14;|¼)/,
        :three_fourths => /(&#190;|&frac34;|¾)/,
        :one_fifth     => /(&#8533;|⅕)/,
        :two_fifths    => /(&#8534;|⅖)/,
        :three_fifths  => /(&#8535;|⅗)/,
        :four_fifths   => /(&#8536;|⅘)/,
        :one_sixth     => /(&#8537;|⅙)/,
        :five_sixths   => /(&#8538;|⅚)/,
        :one_eighth    => /(&#8539;|⅛)/,
        :three_eighths => /(&#8540;|⅜)/,
        :five_eighths  => /(&#8541;|⅝)/,
        :seven_eighths => /(&#8542;|⅞)/,
      }

      WHITESPACE = /\s+/

      class << self
        %w{
          abbreviation
          accented_html_entity
          apostrophe
          characters
          cleanup_characters
          cleanup_html_entities
          currencies
          currencies_simple
          currencies_complex
          html_entities
          html_tag
          smart_punctuation
          vulgar_fractions
          whitespace
        }.each do |conversion_type|
          define_method conversion_type do
            const_get conversion_type.upcase
          end
        end
      end
    end
  end
end