# SVG generators for special flags.
#
# These methods should never need to be called directly.
# @private
class USPSFlags::Generate::Flag
  class << self
    def officer(rank: nil, width: USPSFlags::Config::BASE_FLY, outfile: nil, scale: nil, field: true)
      raise ArgumentError, "No rank specified." if rank.nil?
      @rank = rank.to_s.upcase
      @field = field

      svg = ""
      svg << USPSFlags::Core.headers(scale: scale, title: @rank)
      modify_rank_for_insignia
      @flag_details = USPSFlags::Helpers.flag_details(@rank)
      @trident_color = @field ? :white : @flag_details[:color]
      svg << officer_flag_body

      USPSFlags::Helpers.output(svg, outfile: outfile)
    end

    def special(type, level:, field: true)
      # Paths were designed for a base fly of 3000 pixels, but the base was changed for more useful fractions.
      svg = ""
      svg << "<g transform=\"translate(#{USPSFlags::Config::BASE_FLY/10})\">" unless field
      svg << "<g transform=\"scale(#{Rational(USPSFlags::Config::BASE_FLY,3000).to_f})\">"
      svg << case type
      when :a
        USPSFlags::Core.binoculars(level)
      when :f
        USPSFlags::Core.trumpet(level)
      when :fc
        USPSFlags::Core.anchor
      when :pc
        USPSFlags::Core.lighthouse
      end
      svg << "</g>"
      svg << "</g>" unless field

      svg
    end

    def pennant(type: "CRUISE", outfile: nil, scale: nil)
      type = type.upcase
      svg = ""
      title = { "CRUISE" => "Cruise Pennant", "OIC" => "Officer-in-Charge Pennant" }[type]
      svg << USPSFlags::Core.headers(pennant: true, scale: scale, title: title)
      svg << USPSFlags::Core.pennant(type)
      svg << USPSFlags::Core.footer

      USPSFlags::Helpers.output(svg, outfile: outfile)
    end

    def ensign(outfile: nil, scale: nil)
      svg = ""
      svg << USPSFlags::Core.headers(scale: scale, title: "USPS Ensign")
      svg << USPSFlags::Core.ensign
      svg << USPSFlags::Core.footer

      USPSFlags::Helpers.output(svg, outfile: outfile)
    end

    def wheel(outfile: nil, scale: nil)
      width = 4327.4667
      height = 4286.9333
      svg = ""
      svg << USPSFlags::Core.headers(width: width, height: height, scale: scale, title: "USPS Ensign Wheel")
      svg << USPSFlags::Core.wheel
      svg << USPSFlags::Core.footer

      USPSFlags::Helpers.output(svg, outfile: outfile)
    end

    def us(outfile: nil, scale: nil)
      base_hoist = 2000.to_f
      base_fly = base_hoist * 1.91
      hoist = scale.nil? ? base_hoist : (base_hoist / scale)
      fly = hoist * 1.91
      svg = ""
      svg << USPSFlags::Core.headers(width: fly, height: hoist, scale: scale, title: "US Ensign")
      svg << USPSFlags::Core.us
      svg << USPSFlags::Core.footer

      USPSFlags::Helpers.output(svg, outfile: outfile)
    end

    private
    def get_officer_flag
      if cc?
        USPSFlags::Core::Tridents.cc(@flag_details[:type], trident_color: @trident_color)
      elsif vc?
        USPSFlags::Core::Tridents.vc(@flag_details[:type], trident_color: @trident_color)
      elsif three?
        USPSFlags::Core::Tridents.three(@flag_details[:type], trident_color: @trident_color, field_color: @flag_details[:color])
      elsif two?
        USPSFlags::Core::Tridents.two(@flag_details[:type], trident_color: @trident_color, field_color: @flag_details[:color])
      elsif offset?
        USPSFlags::Core::Tridents.offset(@flag_details[:type], field_color: @flag_details[:color], field: @field)
      elsif special?
        special(@flag_details[:type], level: @flag_details[:level], field: @field)
      else
        USPSFlags::Core.trident(@flag_details[:type], field_color: @flag_details[:color])
      end
    end

    def officer_flag_body
      svg = ""
      svg << USPSFlags::Core.field(style: @flag_details[:style], color: @flag_details[:color]) if @field
      svg << "<g transform=\"translate(-150, 400)\"><g transform=\"scale(0.58333)\">" if @flag_details[:style] == :past
      svg << get_officer_flag
      svg << "</g></g>" if @flag_details[:style] == :past
      svg << USPSFlags::Core.footer
      svg
    end

    def modify_rank_for_insignia
      @rank.slice!(0) if !@field && USPSFlags::Helpers.valid_flags(:past).include?(@rank)
      @rank = "CDR" if @rank == "C"
    end

    def cc?
      @flag_details[:type] == :n && @flag_details[:count] == 3
    end

    def vc?
      @flag_details[:type] == :n && @flag_details[:count] == 2
    end

    def three?
      [:s, :d].include?(@flag_details[:type]) && @flag_details[:count] == 3
    end

    def two?
      [:s, :d].include?(@flag_details[:type]) && @flag_details[:count] == 2
    end

    def offset?
      %w[LT DLT].include?(@rank)
    end

    def special?
      [:a, :f, :fc, :pc].include?(@flag_details[:type])
    end
  end
end