module JsonApiQueryParser

# File lib/json_api_query_parser.rb, line 52
def self.delegate_to_parser(query, request_data)
  PARSE_PARAM.each do |function_name, _value|
    if query =~ PARSE_PARAM[function_name.to_sym]
      request_data = send(function_name, query, request_data)
    end
  end
end

# File lib/json_api_query_parser.rb, line 43
def self.parse_endpoint(endpoint_string, request_data)
  request_split = endpoint_string.split("/")

  request_data[:resource_type] = request_split[0]
  request_data[:identifier] = request_split.length >= 2 ? request_split[1] : nil

  request_data
end

# File lib/json_api_query_parser.rb, line 67
def self.parse_fields(fields_string, request_data)
  target_resource, target_fields, target_fields_string = ""
  field_name_regex = /^fields.*?\=(.*?)$/i

  target_resource = fields_string.scan(PARSE_PARAM[:parse_fields])

  target_fields_string = fields_string.scan(field_name_regex)

  request_data[:fields][target_resource[0][0]] = !request_data[:fields][target_resource[0][0]] ? [] : target_resource[0][0]
  target_fields = target_fields_string[0][0].split(",")

  target_fields.each do |targetField|
    request_data[:fields][target_resource[0][0]] << targetField
  end

  request_data
end

# File lib/json_api_query_parser.rb, line 60
def self.parse_include(include_string, request_data)
  target_string = include_string.split("=")[1]
  request_data[:include] = target_string.split(",")

  request_data
end

# File lib/json_api_query_parser.rb, line 85
def self.parse_page (page_string, request_data)
  page_setting_key, page_setting_value = ""
  page_value_regex = /^page.*?\=(.*?)$/i

  page_setting_key = page_string.scan(PARSE_PARAM[:parse_page])

  page_setting_value = page_string.scan(page_value_regex)

  request_data[:page][page_setting_key[0][0]] = page_setting_value[0][0]

  request_data
end

# File lib/json_api_query_parser.rb, line 33
def self.parse_query_parameters(query_string, request_data)
  query_split = query_string.split("&")

  query_split.each do |query|
    delegate_to_parser(query, request_data)
  end

  request_data
end

# File lib/json_api_query_parser.rb, line 12
def self.parse_request(url)
  request_data = {
    resource_type: nil,
    identifier: nil,
    query_data: {
      include: [],
      fields: {},
      page: {}
    }
  }

  url_split = url.split("?")
  request_data = parse_endpoint(url_split[0], request_data) if url_split[0]

  if url_split[1]
    request_data[:query_data] = parse_query_parameters(url_split[1], request_data[:query_data])
  end

  request_data
end