module Lint

class MissingKeysOnSharedArea < RuboCop::Cop::Cop

MISSING_KEYS_MSG = "Found %<key>s in 'SharedValues' but not in 'output' method. Keys in the 'output' method: %<list>s".freeze

MISSING_OUTPUT_METHOD_MSG = "There are declared keys on the shared area 'SharedValues', but 'output' method has not been found".freeze

MISSING_CONST_DEFINITION_MSG = "Found setting a value for `SharedValues` in a function but the const is not declared in `SharedValues` module".freeze

def_node_search :extract_const_assignment, <<-PATTERN

(casgn nil? $_ ...)

PATTERN

def_node_matcher :find_output_method, <<-PATTERN

(defs (self) :output ...)

PATTERN

def_node_matcher :extract_shared_values_key?, <<-PATTERN

(const (const nil? :SharedValues) $_)

PATTERN

attr_writer :shared_values_constants

def shared_values_constants

@shared_values_constants ||= []

end

def on_module(node)

name, body = *node

return unless name.source == 'SharedValues'

return if body.nil?

consts = extract_const_assignment(node)

consts.each { |const| self.shared_values_constants << const.to_s }

end

def on_defs(node)

return if self.shared_values_constants.empty?

return unless find_output_method(node)

_definee, _method_name, _args, body = *node

return add_offense(node, location: :expression, message: format(MISSING_KEYS_MSG, key: self.shared_values_constants.join(', '), list: [])) if body.nil?

return add_offense(node, location: :expression, message: format(MISSING_KEYS_MSG, key: self.shared_values_constants.join(', '), list: [])) unless body.array_type?

children = body.children.select(&:array_type?)

keys = children.map { |child| child.children.first.source.to_s.gsub(/\s|"|'/, '') }

add_offense(node, location: :expression, message: format(MISSING_KEYS_MSG, key: self.shared_values_constants.join(', '), list: keys.join(', '))) unless self.shared_values_constants.to_set == keys.to_set

end

def on_class(node)

_name, superclass, body = *node

return unless superclass

return unless superclass.loc.name.source == 'Action'

add_offense(node, location: :expression, message: MISSING_OUTPUT_METHOD_MSG) if body.nil? && self.shared_values_constants.any?

return if body.nil?

has_output_method?(body)

end

def on_send(node)

return unless node.arguments?

_, _, *arg_nodes = *node

return unless arg_nodes.count == 2

key = extract_shared_values_key?(node.first_argument)

return if key.nil?

contains_key = self.shared_values_constants.include?(key.to_s)

add_offense(node, location: :expression, message: MISSING_CONST_DEFINITION_MSG) unless contains_key

end

def has_output_method?(node)

return if node.nil?

return if self.shared_values_constants.empty?

if node.defs_type? # A single method

add_offense(node, location: :expression, message: MISSING_OUTPUT_METHOD_MSG) unless output_method?(node)

elsif node.begin_type? # Multiple methods

outputs = node.each_child_node(:defs).select { |n| output_method?(n) }

add_offense(node, location: :expression, message: MISSING_OUTPUT_METHOD_MSG) if outputs.empty?

end

end

def output_method?(node)

_definee, method_name, _args, _body = *node

method_name.to_s == 'output'

end

end

end