module Sonic
  class Execute
    include AwsServices

    def initialize(command, options)
      @command = command
      @options = options
      @filter = @options[:filter].split(',').map{|s| s.strip}
    end

    # aws ssm send-command \
    #   --instance-ids i-030033c20c54bf149 \
    #   --document-name "AWS-RunShellScript" \
    #   --comment "Demo run shell script on Linux Instances" \
    #   --parameters '{"commands":["#!/usr/bin/python","print \"Hello world from python\""]}' \
    #   --query "Command.CommandId"
    def execute
      ssm_options = build_ssm_options
      if @options[:noop]
        UI.noop = true
        command_id = "fake command id"
      else
        resp = ssm.send_command(ssm_options)
        command_id = resp.command.command_id
      end
      UI.say "Command sent to AWS SSM. To check the details of the command:"
      list_command = "aws ssm list-commands --command-id #{command_id}"
      UI.say list_command
      if RUBY_PLATFORM =~ /darwin/
        system("echo '#{list_command}' | pbcopy")
        UI.say "Pro tip: the aws ssm command is already in your copy/paste clipboard."
      end
    end

    def build_ssm_options
      criteria = transform_filter(@filter)
      command = build_command(@command)
      criteria.merge(
        document_name: "AWS-RunShellScript",
        comment: "sonic #{ARGV.join(' ')}",
        parameters: {
          "commands" => command
        }
      )
    end

    def build_command(command)
      if file_path?(command)
        path = file_path(command)
        if File.exist?(path)
          IO.readlines(path).map {|s| s.strip}
        else
          UI.error("File #{path} could not be found. Are you sure it exist?")
          exit 1
        end
      else
        # The script is being feed inline so just join the command together into one script.
        # Still keep in an array form because that's how ssn.send_command with AWS-RunShellScript
        # usually reads the command.
        [command.join(" ")]
      end
    end

    def file_path?(command)
      return false unless command.size == 1
      possible_path = command.first
      possible_path.include?("file://")
    end

    def file_path(command)
      path = command.first
      path = path.sub('file://', '')
      path = "#{@options[:project_root]}/#{path}" if @options[:project_root]
      path
    end

    #
    # Public: Transform the filter to the ssm send_command equivalent options
    #
    # filter  - CLI filter option. Example: hi-web-prod hi-worker-prod hi-clock-prod i-0f7f833131a51ce35
    #
    # Examples
    #
    #   transform_filter(["hi-web-prod", "hi-worker-prod", "i-006a097bb10643e20"])
    #   # => {
    #      instance_ids: ["i-006a097bb10643e20"],
    #      targets: [{key: "Name", values: "hi-web-prod,hi-worker-prod"}]
    #     }
    #
    # Returns the duplicated String.
    def transform_filter(filter)
      valid = validate_filter(filter)
      unless valid
        UI.error("The filter you provided '#{filter.join(',')}' is not valid.")
        UI.say("The filter must either be all instance ids or just a list of tag names.")
        exit 1
      end

      if filter.detect { |i| instance_id?(i) }
        instance_ids = filter
        {instance_ids: instance_ids}
      else
        tags = filter
        targets = [{
          key: "tag:#{tag_name}",
          values: tags
        }]
        {targets: targets}
      end
    end

    # Either all instance ids are no instance ids is a valid filter
    def validate_filter(filter)
      if filter.detect { |i| instance_id?(i) }
        instance_ids = filter.select { |i| instance_id?(i) }
        instance_ids.size == filter.size
      else
        true
      end
    end

    # TODO: make configurable
    def tag_name
      "Name"
    end

    def instance_id?(text)
      text =~ /i-.{17}/
    end
  end
end