class RSpec::Matchers::BuiltIn::Have

def cardinality_expression(query_method)
  expression = "#{target_expression}."
  expression << "#{@collection_name}." if @target_owns_a_collection
  expression << String(query_method)
end

def description
  "have #{relative_expectation} #{@collection_name}"
end

def determine_collection(collection_or_owner)
  if collection_or_owner.respond_to?(@collection_name)
    @target_owns_a_collection = true
    collection_or_owner.__send__(@collection_name, *@args, &@block)
  elsif (@plural_collection_name && collection_or_owner.respond_to?(@plural_collection_name))
    @target_owns_a_collection = true
    collection_or_owner.__send__(@plural_collection_name, *@args, &@block)
  elsif determine_query_method(collection_or_owner)
    collection_or_owner
  else
    collection_or_owner.__send__(@collection_name, *@args, &@block)
  end
end

def determine_query_method(collection)
  QUERY_METHODS.detect {|m| collection.respond_to?(m)}
end

def does_not_match?(collection_or_owner)
  @negative_expectation = true
  @expectation_format_method = "to_not"
  !matches?(collection_or_owner)
end

def enumerator_class
  RUBY_VERSION < '1.9' ? Enumerable::Enumerator : Enumerator
end

def errors_on_args_list
  list = @args.first.inspect
  context = validation_context
  list << ", :context => #{context}" if context
  list
end

def expectation_expression(query_method, target = nil)
  target ||= target_expression
  if @negative_expectation
    RSpec::Expectations::Syntax.negative_expression(target, original_matcher_expression)
  else
    RSpec::Expectations::Syntax.positive_expression(target, original_matcher_expression)
  end
end

def expectation_format_method
  if @relativity == :exactly
    @expectation_format_method
  else
    "to"
  end
end

def failure_message_for_should
  "expected #{relative_expectation} #{@collection_name}, got #{@actual}"
end

def failure_message_for_should_not
  if @relativity == :exactly
    return "expected target not to have #{@expected} #{@collection_name}, got #{@actual}"
  elsif @relativity == :at_most
    return <<-EOF
fe confusing enough?
of having to figure out the meaning of this:
ctations::Syntax.negative_expression("actual", "have_at_most(#{@expected}).#{@collection_name}")}
mend that you use this instead:
ctations::Syntax.positive_expression("actual", "have_at_least(#{@expected + 1}).#{@collection_name}")}
  elsif @relativity == :at_least
    return <<-EOF
fe confusing enough?
of having to figure out the meaning of this:
ctations::Syntax.negative_expression("actual", "have_at_least(#{@expected}).#{@collection_name}")}
mend that you use this instead:
ctations::Syntax.positive_expression("actual", "have_at_most(#{@expected - 1}).#{@collection_name}")}
  end
end

def for_rspec_rails_error_on?
  defined?(RSpec::Rails) &&
    /\.errors?_on\b/ =~ original_matcher_expression
end

def initialize(expected, relativity=:exactly)
  @expected = case expected
              when :no then 0
              when String then expected.to_i
              else expected
              end
  @relativity = relativity
  @actual = @collection_name = @plural_collection_name = nil
  @target_owns_a_collection = false
  @negative_expectation = false
  @expectation_format_method = "to"
end

def matcher_method
  case @relativity
  when :exactly
    "have"
  when :at_most
    "have_at_most"
  when :at_least
    "have_at_least"
  end
end

def matches?(collection_or_owner)
  collection = determine_collection(collection_or_owner)
  case collection
  when enumerator_class
    for query_method in QUERY_METHODS
      next unless collection.respond_to?(query_method)
      @actual = collection.__send__(query_method)
      if @actual
        print_deprecation_message(query_method)
        break
      end
    end
    raise not_a_collection if @actual.nil?
  else
    query_method = determine_query_method(collection)
    raise not_a_collection unless query_method
    @actual = collection.__send__(query_method)
    print_deprecation_message(query_method)
  end
  case @relativity
  when :at_least then @actual >= @expected
  when :at_most  then @actual <= @expected
  else                @actual == @expected
  end
end

def method_missing(method, *args, &block)
  @collection_name = method
  if inflector = (defined?(ActiveSupport::Inflector) && ActiveSupport::Inflector.respond_to?(:pluralize) ? ActiveSupport::Inflector : (defined?(Inflector) ? Inflector : nil))
    @plural_collection_name = inflector.pluralize(method.to_s)
  end
  @args = args
  @block = block
  self
end

def not_a_collection
  "expected #{@collection_name} to be a collection but it does not respond to #length, #size or #count"
end

def original_matcher_expression
  "#{matcher_method}(#{@expected}).#{@collection_name}"
end

def print_deprecation_message(query_method)
  deprecation_message = "the rspec-collection_matchers gem "
  deprecation_message << "or replace your expectation with something like "
  if for_rspec_rails_error_on?
    # It is supposed to be safe to be able to convert the args array to
    # a string. This is because the `errors_on` method only takes two
    # valid arguments: attribute name (symbol/string) and a hash
    deprecated_call = expectation_expression(query_method, "record")
    deprecated_call << "(#{errors_on_args_list})" unless @args.empty?
    deprecation_message << <<-EOS.gsub(/^\s+\|/, '')
      |
      |
      |    #{record_valid_expression}
      |    expect(#{record_errors_expression(query_method)}).#{expectation_format_method} #{suggested_matcher_expression}
      |
    EOS
  else
    deprecated_call = expectation_expression(query_method)
    deprecation_message << "`expect(#{cardinality_expression(query_method)}).#{expectation_format_method} #{suggested_matcher_expression}`"
  end
  RSpec.deprecate("`#{deprecated_call}`",
    :replacement => deprecation_message,
    :type        => "the have matcher"
  )
end

def record_errors_expression(query_method)
  attribute = (@args.first || :attr)
  "record.errors[#{attribute.inspect}].#{String(query_method)}"
end

def record_valid_expression
  expression = "record.valid?"
  if on_context = validation_context
    expression << "(#{on_context})"
  end
  expression
end

def relative_expectation
  "#{relativities[@relativity]}#{@expected}"
end

def relativities
  @relativities ||= {
    :exactly => "",
    :at_least => "at least ",
    :at_most => "at most "
  }
end

def respond_to?(m)
  @expected.respond_to?(m) || super
end

def suggested_matcher_expression
  send("suggested_matcher_expression_for_#{@relativity}")
end

def suggested_matcher_expression_for_at_least
  if @negative_expectation
    "be < #{@expected}"
  else
    "be >= #{@expected}"
  end
end

def suggested_matcher_expression_for_at_most
  if @negative_expectation
    "be > #{@expected}"
  else
    "be <= #{@expected}"
  end
end

def suggested_matcher_expression_for_exactly
  "eq(#{@expected})"
end

def target_expression
  if @target_owns_a_collection
    'collection_owner'
  else
    'collection'
  end
end

def validation_context
  return unless Hash === @args.last
  @args.last[:context].inspect
end