require "uri"

module Shipit
  module Cli
    # This class maintains all system-wide configuration for *shipit*. It properly
    # applies the correct source of configuration values based on the different contexts and
    # also makes sure that compulsory data are not missing.
    #
    class Configuration
      # List of all the configuration attributes stored for use within the gem
      ATTRIBUTES = [:endpoint, :private_token, :protected_branches]

      attr_accessor :endpoint, :private_token, :protected_branches

      # Apply a configuration hash to a configuration instance
      #
      # @example Override one of the configuration attributes
      #   config = Shipit::Cli::Configuration.new
      #   config.apply(private_token: 'supersecret')
      #   config.private_token #=> "supersecret"
      #
      # @param attributes [Hash] list of key/values to apply to the configuration
      # @return [Object] the configuration object
      #
      def apply(attributes = {})
        prepared_attributes = prepare_attributes attributes
        prepared_attributes.each_pair do |attribute, value|
          send("#{attribute}=", value)
        end
        self
      end

      # The configuration instance formatted as a stringified hash
      #
      # @example Override one of the configuration attributes
      #   config = Shipit::Cli::Configuration.new
      #   config.to_hash
      #   #=> { "endpoint" => "https://gitlab.example.com/api/v3", "private_token" => "supersecret" }
      #
      # @return [Hash] the configuration object as a Hash
      #
      def to_hash
        config_hash = ATTRIBUTES.inject({}) do |hash, attr|
          hash["#{attr}"] = instance_variable_get("@#{attr}")
          hash
        end
        Shipit::Cli::Sanitizer.symbolize config_hash
      end

      # Write a configuration summary to STDOUT, useful for output in the CLI
      #
      def to_stdout
        to_hash.each_pair do |attribute, value|
          puts format("%-20s %-50s", "#{attribute}:", value)
        end
        nil
      end

      def motd_list
        File.readlines(File.expand_path('../../motd', __FILE__)).map(&:chomp)
      end

      private

      # Symbolize keys and remove nil or duplicate attributes
      # The attributes usually passed to our configuration class by the CLI
      # are usually full of duplicates and unconsistant keys, we make sure
      # to clean up that input, before doing any configuration work.
      #
      # @param attributes [Hash] list of key/values
      # @return [Hash] a clean list of key/values
      #
      def prepare_attributes(attributes)
        # Convert string keys to symbols
        symboled_attributes = Shipit::Cli::Sanitizer.symbolize attributes
        # Clean up user_attributes from unwanted, nil and duplicate options
        symboled_attributes.select { |key, _| ATTRIBUTES.include? key }.delete_if { |_, v| v.nil? }
      end
    end
  end
end