# frozen_string_literal: true

#
# Copyright (C) 2011 - present Instructure, Inc.
#
# This file is part of Canvas.
#
# Canvas is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the Free
# Software Foundation, version 3 of the License.
#
# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along
# with this program. If not, see <http://www.gnu.org/licenses/>.
#

module Lti
  module AppUtil
    TOOL_DISPLAY_TEMPLATES = {
      "borderless" => { template: "lti/unframed_launch", layout: "borderless_lti" }.freeze,
      "in_rce" => { template: "lti/in_rce_launch", layout: false }.freeze,
      "full_width" => { template: "lti/full_width_launch" }.freeze,
      "in_context" => { template: "lti/framed_launch" }.freeze,
      "in_nav_context" => { template: "lti/full_width_in_context" }.freeze,
      "default" => { template: "lti/framed_launch" }.freeze,
      "full_width_in_context" => { template: "lti/full_width_in_context" }.freeze,
      "full_width_with_nav" => { template: "lti/full_width_with_nav" }.freeze,
    }.freeze
    BLACKLIST_WILDCARD = "*" # to set up 'deny all' rules

    def self.display_template(display_type = nil, display_override: nil)
      unless TOOL_DISPLAY_TEMPLATES.key?(display_type)
        display_type = "default"
      end

      if display_override && TOOL_DISPLAY_TEMPLATES.include?(display_override)
        display_type = display_override
      end

      TOOL_DISPLAY_TEMPLATES[display_type].dup
    end

    def self.custom_params(raw_post)
      form_pairs = URI.decode_www_form(raw_post)
      form_pairs.each_with_object({}) do |(k, v), hash|
        captures = k.match(/^external_tool\[custom_fields\[(.*)\]\]/).try(:captures)
        hash[captures.first] = v if captures.present?
      end
    end

    def self.allowed?(candidate, whitelist, blacklist)
      return true if whitelist.blank? && blacklist.blank?
      return false if blacklist.present? && (blacklist.include?(candidate) || blacklist.include?(BLACKLIST_WILDCARD))

      whitelist.blank? || whitelist.include?(candidate)
    end
  end
end
