#
#       ActiveFacts CQL Parser.
#       Parse rules the English syntax of CQL.
#
# Copyright (c) 2009 Clifford Heath. Read the LICENSE file.
#
module ActiveFacts
  module CQL
    grammar Language

      rule subtype_prefix
        'is' s 'a' s ('kind'/'subtype') s 'of' S
      end

      rule defined_as
        s 'is' s 'defined' S as s
      end

      rule identified_by
        identified s by s
      end

      rule quantifier
        each s                    { def value; [1, nil]; end }
        / some s                  { def value; nil; end }
          # REVISIT: "Some" means that any prior occurrence of this role player is to be ignored; this is a new occurrence
          # "that" on the other hand means that this role player was *previously* designated using "some".
          # These distinctions are lost here
        / that s                  { def value; nil; end }
        / one s                   { def value; [1, 1]; end }
        / no s                    { def value; [0, 0]; end }
        / exactly s quantity      { def value; q = quantity.value; [q, q]; end }
        / at s least s quantity most:( and s at s most s q:quantity )?
                                  { def value;
                                      [ quantity.value,
                                        most.empty? ? nil : most.q.value
                                      ]
                                    end
                                  }
        / at s most s quantity    { def value; [ nil, quantity.value ]; end }
        / from s numeric_range s  { def value; numeric_range.value; end }
        / either_all_or_none s    { def value; [ -1, 1 ]; end }
      end

      rule quantity
        one s                     { def value; 1; end }
        / number s                { def value; number.value; end }
      end

      rule acyclic 'acyclic' !alphanumeric end
      rule alias 'alias' !alphanumeric end 
      rule all 'all' !alphanumeric end
      rule and 'and' !alphanumeric end
      rule as 'as' !alphanumeric end
      rule at 'at' !alphanumeric end
      rule by 'by' !alphanumeric end 
      rule definitely 'definitely' !alphanumeric end
      rule each 'each' !alphanumeric end 
      rule either 'either' !alphanumeric end 
      rule entity 'entity' !alphanumeric end 
      rule exactly 'exactly' !alphanumeric end
      rule false 'false' !alphanumeric end 
      rule from  'from' !alphanumeric end
      rule identified ('known'/'identified') !alphanumeric end 
      rule if 'if' !alphanumeric end
      rule import 'import' !alphanumeric end
      rule includes 'includes' !alphanumeric end
      rule intransitive 'intransitive' !alphanumeric end
      rule is 'is' !alphanumeric end 
      rule its 'its' !alphanumeric end
      rule least 'least' !alphanumeric end
      rule matches 'matches' !alphanumeric end
      rule maybe 'maybe' !alphanumeric end
      rule most 'most' !alphanumeric end
      rule no 'no' !alphanumeric end
      rule none 'none' !alphanumeric end
      rule not 'not' !alphanumeric end
      rule either_all_or_none either s all s or s none end
      rule one 'one' !alphanumeric end
      rule only 'only' !alphanumeric end
      rule or 'or' !alphanumeric end 
      rule restricted 'restricted' !alphanumeric end
      rule returning 'returning' !alphanumeric end
      rule some 'some' !alphanumeric end
      rule static 'static' !alphanumeric end
      rule symmetric 'symmetric' !alphanumeric end
      rule that 'that' !alphanumeric end
      rule to 'to' !alphanumeric end
      rule transient 'transient' !alphanumeric end
      rule transitive 'transitive' !alphanumeric end
      rule true 'true' !alphanumeric end 
      rule vocabulary 'vocabulary' !alphanumeric end 
      rule where 'where' !alphanumeric end 

    end
  end
end