require 'rubygems/spec_fetcher'
require 'rubygems/command_manager'

module Fastlane
  module Actions
    # Makes sure fastlane tools are up-to-date when running fastlane 
    class UpdateFastlaneAction < Action

      ALL_TOOLS = [
        "fastlane",
        "fastlane_core",
        "deliver",
        "snapshot",
        "frameit",
        "pem",
        "sigh",
        "produce",
        "cert",
        "codes",
        "credentials_manager"
      ]

      def self.run(options)
        if options[:no_update]
          return
        end

        tools_to_update = options[:tools].split ',' unless options[:tools].nil?
        tools_to_update ||= all_installed_tools

        if tools_to_update.count == 0
          Helper.log.error "No tools specified or couldn't find any installed fastlane.tools".red
          return
        end

        updater = Gem::CommandManager.instance[:update]
        cleaner = Gem::CommandManager.instance[:cleanup]

        sudo_needed = !File.writable?(Gem.dir)

        if sudo_needed
          Helper.log.warn "It seems that your Gem directory is not writable by your current User."
          Helper.log.warn "Fastlane would need sudo rights to update itself, however, running 'sudo fastlane' is not recommended."
          Helper.log.warn "If you still want to use this action, please read the Actions.md documentation on a guide how to set this up."
          return
        end

        highest_versions = updater.highest_installed_gems.keep_if {|key| tools_to_update.include? key }
        update_needed = updater.which_to_update(highest_versions, tools_to_update)

        if update_needed.count == 0
          Helper.log.info "Nothing to update ✅".yellow
          return
        end

        # suppress updater output - very noisy
        Gem::DefaultUserInteraction.ui = Gem::SilentUI.new

        update_needed.each do |tool_info| 
          tool = tool_info[0]
          local_version = Gem::Version.new(highest_versions[tool].version)
          latest_version = FastlaneCore::UpdateChecker.fetch_latest(tool)
          Helper.log.info "Updating #{tool} from #{local_version} to #{latest_version} ... 🚀"

          # Approximate_recommendation will create a string like "~> 0.10" from a version 0.10.0, e.g. one that is valid for versions >= 0.10 and <1.0
          updater.update_gem tool, Gem::Requirement.new(local_version.approximate_recommendation)
          
          Helper.log.info "Finished updating #{tool}"
        end

        all_updated_tools = updater.installer.installed_gems.select do |updated_tool|
          updated_tool.version > highest_versions[updated_tool.name].version
        end

        unless all_updated_tools.empty?
          Helper.log.info "Cleaning up old versions..."
          cleaner.options[:args] = all_updated_tools.map {|t| t.name }
          cleaner.execute
          Helper.log.info "fastlane.tools succesfully updated! I will now restart myself... 😴"
          
          # Set no_update to true so we don't try to update again
          exec "FL_NO_UPDATE=true #{$PROGRAM_NAME} #{ARGV.join ' '}"
        else 
          Helper.log.info "All fastlane tools are up-to-date!"
        end
      end

      def self.all_installed_tools
        Gem::Specification.select { |s| ALL_TOOLS.include? s.name }.map {|s| s.name}.uniq
      end

      def self.description
        "Makes sure fastlane-tools are up-to-date when running fastlane"
      end

      def self.available_options
        [
          FastlaneCore::ConfigItem.new(key: :tools,
                                       env_name: "FL_TOOLS_TO_UPDATE",
                                       description: "Comma separated list of fastlane tools to update (e.g. fastlane,deliver,sigh). If not specified, all currently installed fastlane-tools will be updated",
                                       optional: true),
         FastlaneCore::ConfigItem.new(key: :no_update,
                                      env_name: "FL_NO_UPDATE",
                                      description: "Don't update during this run. Defaults to false",
                                      is_string: false,
                                      default_value: false),
        ]
      end

      def self.author
        "milch"
      end

      def self.is_supported?(platform)
        true
      end
    end
  end
end