module Arel
  module Predications
    def not_eq other
      Nodes::NotEqual.new self, quoted_node(other)
    end

    def not_eq_any others
      grouping_any :not_eq, others
    end

    def not_eq_all others
      grouping_all :not_eq, others
    end

    def eq other
      Nodes::Equality.new self, quoted_node(other)
    end

    def eq_any others
      grouping_any :eq, others
    end

    def eq_all others
      grouping_all :eq, quoted_array(others)
    end

    def between other
      if equals_quoted?(other.begin, -Float::INFINITY)
        if equals_quoted?(other.end, Float::INFINITY)
          not_in([])
        elsif other.exclude_end?
          lt(other.end)
        else
          lteq(other.end)
        end
      elsif equals_quoted?(other.end, Float::INFINITY)
        gteq(other.begin)
      elsif other.exclude_end?
        gteq(other.begin).and(lt(other.end))
      else
        left = quoted_node(other.begin)
        right = quoted_node(other.end)
        Nodes::Between.new(self, left.and(right))
      end
    end

    def in other
      case other
      when Arel::SelectManager
        Arel::Nodes::In.new(self, other.ast)
      when Range
        if $VERBOSE
          warn <<-eowarn
Passing a range to `#in` is deprecated. Call `#between`, instead.
          eowarn
        end
        between(other)
      when Enumerable
        Nodes::In.new self, quoted_array(other)
      else
        Nodes::In.new self, quoted_node(other)
      end
    end

    def in_any others
      grouping_any :in, others
    end

    def in_all others
      grouping_all :in, others
    end

    def not_between other
      if equals_quoted?(other.begin, -Float::INFINITY)
        if equals_quoted?(other.end, Float::INFINITY)
          self.in([])
        elsif other.exclude_end?
          gteq(other.end)
        else
          gt(other.end)
        end
      elsif equals_quoted?(other.end, Float::INFINITY)
        lt(other.begin)
      else
        left = lt(other.begin)
        right = if other.exclude_end?
          gteq(other.end)
        else
          gt(other.end)
        end
        left.or(right)
      end
    end

    def not_in other
      case other
      when Arel::SelectManager
        Arel::Nodes::NotIn.new(self, other.ast)
      when Range
        if $VERBOSE
          warn <<-eowarn
Passing a range to `#not_in` is deprecated. Call `#not_between`, instead.
          eowarn
        end
        not_between(other)
      when Enumerable
        Nodes::NotIn.new self, quoted_array(other)
      else
        Nodes::NotIn.new self, quoted_node(other)
      end
    end

    def not_in_any others
      grouping_any :not_in, others
    end

    def not_in_all others
      grouping_all :not_in, others
    end

    def matches other, escape = nil, case_sensitive = false
      Nodes::Matches.new self, quoted_node(other), escape, case_sensitive
    end

    def matches_any others, escape = nil, case_sensitive = false
      grouping_any :matches, others, escape, case_sensitive
    end

    def matches_all others, escape = nil, case_sensitive = false
      grouping_all :matches, others, escape, case_sensitive
    end

    def does_not_match other, escape = nil, case_sensitive = false
      Nodes::DoesNotMatch.new self, quoted_node(other), escape, case_sensitive
    end

    def does_not_match_any others, escape = nil
      grouping_any :does_not_match, others, escape
    end

    def does_not_match_all others, escape = nil
      grouping_all :does_not_match, others, escape
    end

    def gteq right
      Nodes::GreaterThanOrEqual.new self, quoted_node(right)
    end

    def gteq_any others
      grouping_any :gteq, others
    end

    def gteq_all others
      grouping_all :gteq, others
    end

    def gt right
      Nodes::GreaterThan.new self, quoted_node(right)
    end

    def gt_any others
      grouping_any :gt, others
    end

    def gt_all others
      grouping_all :gt, others
    end

    def lt right
      Nodes::LessThan.new self, quoted_node(right)
    end

    def lt_any others
      grouping_any :lt, others
    end

    def lt_all others
      grouping_all :lt, others
    end

    def lteq right
      Nodes::LessThanOrEqual.new self, quoted_node(right)
    end

    def lteq_any others
      grouping_any :lteq, others
    end

    def lteq_all others
      grouping_all :lteq, others
    end

    private

    def grouping_any method_id, others, *extras
      nodes = others.map {|expr| send(method_id, expr, *extras)}
      Nodes::Grouping.new nodes.inject { |memo,node|
        Nodes::Or.new(memo, node)
      }
    end

    def grouping_all method_id, others, *extras
      nodes = others.map {|expr| send(method_id, expr, *extras)}
      Nodes::Grouping.new Nodes::And.new(nodes)
    end

    def quoted_node(other)
      Nodes.build_quoted(other, self)
    end

    def quoted_array(others)
      others.map { |v| quoted_node(v) }
    end

    def equals_quoted?(maybe_quoted, value)
      if maybe_quoted.is_a?(Nodes::Quoted)
        maybe_quoted.val == value
      else
        maybe_quoted == value
      end
    end
  end
end