# Container class for helper methods.
class USPSFlags::Helpers
  class << self
    # Valid options for flag generation.
    #
    # @param [Symbol] type Specify subset of flags.
    # @option type [Symbol] :all All flags
    # @option type [Symbol] :officer Officer flags
    # @option type [Symbol] :insignia Insignia-eligible officer flags (no past officers)
    # @option type [Symbol] :squadron Squadron-level officer flags
    # @option type [Symbol] :district District-level officer flags
    # @option type [Symbol] :national National-level officer flags
    # @option type [Symbol] :special Special flags
    # @option type [Symbol] :us US flag
    # @return [Array] Valid options for flag generation (based on the provided type).
    def valid_flags(type = :all)
      squadron_past = %w[PLTC PC]
      squadron_elected = %w[1LT LTC CDR]
      squadron_swallowtail = %w[PORTCAP FLEETCAP LT FLT]
      district_past = %w[PDLTC PDC]
      district_elected = %w[D1LT DLTC DC]
      district_swallowtail = %w[DLT DAIDE DFLT]
      national_past = %w[PSTFC PRC PVC PCC]
      national_elected = %w[NAIDE NFLT STFC RC VC CC]
      special = %w[CRUISE OIC ENSIGN WHEEL]
      us = %w[US]

      squadron = squadron_past + squadron_elected + squadron_swallowtail
      district = district_past + district_elected + district_swallowtail
      national = national_past + national_elected
      past = squadron_past + district_past + national_past

      case type
      when :all
        squadron + district + national + special + us
      when :officer
        squadron + district + national
      when :insignia
        squadron + district + national - past
      when :squadron
        squadron
      when :district
        district
      when :national
        national
      when :special
        special
      when :us
        us
      when :past
        past
      when :swallowtail
        past + squadron_swallowtail + district_swallowtail
      when :bridge
        squadron_elected.last(2) + squadron_past.last(2) + 
        district_elected.last(2) + district_past.last(2) + 
        national_elected.last(2) + national_past.last(2)
      when :command
        [squadron_elected.last, squadron_past.last,
        district_elected.last, district_past.last,
        national_elected.last, national_past.last]
      end
    end

    # Gets the generation details for the given rank.
    #
    # This is used USPSFlags::Generate, and should never need to be called directly.
    # @private
    def flag_details(rank)
      {
        style: flag_style(rank),
        color: flag_color(rank),
        type:  flag_type(rank),
        level: flag_level(rank),
        count: flag_count(rank)
      }
    end

    # Displays an overlay grid with regularly spaced locator markers.
    #
    # This is useful for adjusting or creating new SVG data generators, but should not otherwise need to be called.
    # @private
    def grid(width: USPSFlags::Config::BASE_FLY, height: USPSFlags::Config::BASE_HOIST)
      <<~SVG
        <circle cx="0" cy="0" r="#{width/60}" fill="#000000" fill-opacity="0.4" />
        <circle cx="#{width}" cy="0" r="#{width/60}" fill="#000000" fill-opacity="0.4" />
        <circle cx="#{width}" cy="#{height}" r="#{width/60}" fill="#000000" fill-opacity="0.4" />
        <circle cx="0" cy="#{height}" r="#{width/60}" fill="#000000" fill-opacity="0.4" />

        <circle cx="#{width*1/4}" cy="#{height/2}" r="#{width/60}" fill="#999999" fill-opacity="0.4" />
        <circle cx="#{width*3/4}" cy="#{height/2}" r="#{width/60}" fill="#999999" fill-opacity="0.4" />

        <circle cx="#{width/2}" cy="#{height*1/4}" r="#{width/60}"  fill="#999999" fill-opacity="0.4" />
        <circle cx="#{width/2}" cy="#{height/2}" r="#{width/60}"  fill="#000000" fill-opacity="0.4" />
        <circle cx="#{width/2}" cy="#{height/2}" r="#{width/75}"  fill="#CCCCCC" fill-opacity="0.4" />
        <circle cx="#{width/2}" cy="#{height/2}" r="#{width/100}" fill="#000000" fill-opacity="0.4" />
        <circle cx="#{width/2}" cy="#{height*3/4}" r="#{width/60}"  fill="#999999" fill-opacity="0.4" />

        <line x1="0" y1="0" x2="#{width}" y2="0" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="0" y1="#{height*1/4}" x2="#{width}" y2="#{height*1/4}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="0" y1="#{height/2}" x2="#{width}" y2="#{height/2}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="0" y1="#{height*3/4}" x2="#{width}" y2="#{height*3/4}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="0" y1="#{height}" x2="#{width}" y2="#{height}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />

        <line y1="0" x1="0" y2="#{height}" x2="0" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width*1/6}" y2="#{height}" x2="#{width*1/6}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width*2/6}" y2="#{height}" x2="#{width*2/6}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width*3/6}" y2="#{height}" x2="#{width*3/6}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width*4/6}" y2="#{height}" x2="#{width*4/6}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width*5/6}" y2="#{height}" x2="#{width*5/6}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line y1="0" x1="#{width}" y2="#{height}" x2="#{width}" stroke="#333333" stroke-width="#{width/600}" stroke-opacity="0.5" />

        <line x1="#{width/2}" y1="#{height*1/4}" x2="#{width*3/4}" y2="#{height/2}" stroke="#999999" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="#{width*3/4}" y1="#{height/2}" x2="#{width/2}" y2="#{height*3/4}" stroke="#999999" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="#{width/2}" y1="#{height*3/4}" x2="#{width*1/4}" y2="#{height/2}" stroke="#999999" stroke-width="#{width/600}" stroke-opacity="0.5" />
        <line x1="#{width*1/4}" y1="#{height/2}" x2="#{width/2}" y2="#{height*1/4}" stroke="#999999" stroke-width="#{width/600}" stroke-opacity="0.5" />

      SVG
    end

    # Displays an overlay indicator of concentric circles and radiating lines.
    #
    # This is useful for adjusting or creating new SVG data generators, but should not otherwise need to be called.
    # @private
    def locator
      <<~SVG
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY*2}" fill="#000000" fill-opacity="0.4" />
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY}" fill="#333333" fill-opacity="0.4" />
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY/2}" fill="#666666" fill-opacity="0.4" />
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY/4}" fill="#999999" fill-opacity="0.4" />
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY/8}" fill="#CCCCCC" fill-opacity="0.4" />
        <circle cx="0" cy="0" r="#{USPSFlags::Config::BASE_FLY/16}" fill="#FFFFFF" fill-opacity="0.4" />

        <line x1="-#{USPSFlags::Config::BASE_FLY}" y1="-#{USPSFlags::Config::BASE_HOIST}" x2="#{USPSFlags::Config::BASE_FLY}" y2="#{USPSFlags::Config::BASE_HOIST}"  stroke="#FFFFFF" stroke-width="#{USPSFlags::Config::BASE_FLY/600}" />
        <line x1="-#{USPSFlags::Config::BASE_FLY}" y1="#{USPSFlags::Config::BASE_HOIST}" x2="#{USPSFlags::Config::BASE_FLY}" y2="-#{USPSFlags::Config::BASE_HOIST}" stroke="#FFFFFF" stroke-width="#{USPSFlags::Config::BASE_FLY/600}" />
        <line x1="0" y1="#{USPSFlags::Config::BASE_HOIST}" x2="0" y2="-#{USPSFlags::Config::BASE_HOIST}" stroke="#FFFFFF" stroke-width="#{USPSFlags::Config::BASE_FLY/600}" />
        <line x1="-#{USPSFlags::Config::BASE_FLY}" y1="0" x2="#{USPSFlags::Config::BASE_FLY}" y2="0" stroke="#FFFFFF" stroke-width="#{USPSFlags::Config::BASE_FLY/600}" />

        <rect x="0" y="0" width="#{USPSFlags::Config::BASE_FLY/30}" height="#{USPSFlags::Config::BASE_FLY/30}" fill="#333333" fill-opacity="0.6" />
      SVG
    end

    # Creates a vertical arrow for the trident spec sheet.
    #
    # This is used USPSFlags::Core.trident_spec, and should never need to be called directly.
    # @private
    def v_arrow(x, top, bottom, pointer_top = nil, pointer_bottom = nil, label: nil, label_offset: (USPSFlags::Config::BASE_FLY/120), label_offset_y: 0, label_align: "left", color: "#CCCCCC", stroke_width: (USPSFlags::Config::BASE_FLY/600), stroke_dash: "10, 10", font_size: (USPSFlags::Config::BASE_FLY/60), arrow_size: (USPSFlags::Config::BASE_FLY/120), fly: USPSFlags::Config::BASE_FLY, unit: nil)
      label = bottom - top if label.nil?
      label = label.to_i if label - label.to_i == 0
      label = Rational(label) * fly / USPSFlags::Config::BASE_FLY
      if label == label.to_i
        label = label.to_i
        label_fraction = ""
      else
        label, label_fraction = label.to_simplified_a
      end
      svg = ""
      unless pointer_top.nil?
        svg << <<~SVG
          <line x1="#{x}" y1="#{top}" x2="#{pointer_top}" y2="#{top}" stroke="#{color}" stroke-width="#{stroke_width}" stroke-dasharray="#{stroke_dash}" />
        SVG
      end
      unless pointer_bottom.nil?
        svg << <<~SVG
          <line x1="#{x}" y1="#{bottom}" x2="#{pointer_bottom}" y2="#{bottom}" stroke="#{color}" stroke-width="#{stroke_width}" stroke-dasharray="#{stroke_dash}" />
        SVG
      end

      svg << <<~SVG
        <path d="M#{x} #{top} l #{arrow_size} #{arrow_size} M#{x} #{top} l -#{arrow_size} #{arrow_size} M#{x} #{top} l 0 #{bottom - top} l #{arrow_size} -#{arrow_size} M#{x} #{bottom} l -#{arrow_size} -#{arrow_size}" stroke="#{color}" stroke-width="#{stroke_width}" fill="none" />
        <g>
          <style><![CDATA[tspan{font-size: #{USPSFlags::Config::FRACTION_SCALE}%;}]]></style>
          <text x="#{x + label_offset}" y="#{(top+bottom)/2+(USPSFlags::Config::BASE_HOIST/150)+label_offset_y}" font-family="sans-serif" font-size="#{font_size}px" fill="#041E42" text-anchor="#{label_align}">#{label} <tspan>#{label_fraction}</tspan> #{unit}</text>
        </g>
      SVG

      svg
    end

    # Creates a horizontal arrow for the trident spec sheet.
    #
    # This is used USPSFlags::Core.trident_spec, and should never need to be called directly.
    # @private
    def h_arrow(y, left, right, pointer_left = nil, pointer_right = nil, label: nil, label_offset: (USPSFlags::Config::BASE_FLY/45), label_offset_x: 0, label_align: "middle", color: "#CCCCCC", stroke_width: (USPSFlags::Config::BASE_FLY/600), stroke_dash: "10, 10", font_size: (USPSFlags::Config::BASE_FLY/60), arrow_size: (USPSFlags::Config::BASE_FLY/120), fly: USPSFlags::Config::BASE_FLY, unit: nil)
      label = right - left if label.nil?
      label = label.to_i if label - label.to_i == 0
      label = Rational(label) * fly / USPSFlags::Config::BASE_FLY
      if label == label.to_i
        label = label.to_i
        label_fraction = ""
      else
        label, label_fraction = label.to_simplified_a
      end
      svg = ""
      unless pointer_left.nil?
        svg << <<~SVG
          <line x1="#{left}" y1="#{y}" x2="#{left}" y2="#{pointer_left}" stroke="#{color}" stroke-width="#{stroke_width}" stroke-dasharray="#{stroke_dash}" />
        SVG
      end
      unless pointer_right.nil?
        svg << <<~SVG
          <line x1="#{right}" y1="#{y}" x2="#{right}" y2="#{pointer_right}" stroke="#{color}" stroke-width="#{stroke_width}" stroke-dasharray="#{stroke_dash}" />
        SVG
      end

      svg << <<~SVG
        <path d="M#{left} #{y} l #{arrow_size} #{arrow_size} M#{left} #{y} l #{arrow_size} -#{arrow_size} M#{left} #{y} l #{right - left} 0 l -#{arrow_size} -#{arrow_size} M#{right} #{y} l -#{arrow_size} #{arrow_size}" stroke="#{color}" stroke-width="#{stroke_width}" fill="none" />
        <g>
          <style><![CDATA[tspan{font-size: #{USPSFlags::Config::FRACTION_SCALE}%;}]]></style>
          <text x="#{(left+right)/2+label_offset_x}" y="#{y + label_offset}" font-family="sans-serif" font-size="#{font_size}px" fill="#041E42" text-anchor="#{label_align}">#{label} <tspan>#{label_fraction}</tspan> #{unit}</text>
        </g>
      SVG

      svg
    end

    # Resizes and saves a PNG image.
    #
    # This is used USPSFlags::Generate, and should never need to be called directly.
    # @private
    def resize_png(png_ins_file, flag:, size:, size_key:)
      MiniMagick::Tool::Convert.new do |convert|
        convert << "-background" << "none"
        convert << "-format" << "png"
        convert << "-resize" << "#{size}"
        convert << png_ins_file
        convert << "#{USPSFlags::Config.flags_dir}/PNG/insignia/#{flag}.#{size_key}.png"
      end
    end

    # Image sizes for generated PNG images.
    #
    # This is used USPSFlags::Generate, and should never need to be called directly.
    # @private
    def png_sizes
      {1500 => "H", 1000 => "K", 500 => "D", "thumb" => "T"}
    end

    # Gets size key for saving PNG images.
    #
    # This is used USPSFlags::Generate, and should never need to be called directly.
    # @private
    def size_and_key(size:, flag:)
      return [size, size] unless size == "thumb"

      size = case flag
      when "ENSIGN"
        200
      when "US"
        300
      else
        150
      end

      [size, "thumb"]
    end

    # Prints message(s) to the console and logs them.
    #
    # This should never need to be called directly.
    # @private
    def log(*messages)
      ::FileUtils.mkdir_p(USPSFlags::Config.log_path)
      outputs = [STDOUT]

      begin
        log_file = File.open("#{USPSFlags::Config.log_path}/flag.log", 'a')
        outputs << log_file
      rescue Errno::EACCES => e
        puts "\nError accessing log file." unless USPSFlags::Config.log_fail_quietly
      end

      messages.each do |message|
        outputs.each { |f| f.write(message) }
      end

      messages
    ensure
      log_file.close if log_file.is_a?(File)
    end

    private
    def flag_style(rank)
      if valid_flags(:past).include?(rank)
        :past
      elsif valid_flags(:swallowtail).include?(rank)
        :swallowtail
      else
        :regular
      end
    end

    def flag_color(rank)
      if valid_flags(:command).include?(rank)
        count = 3
        :blue
      elsif valid_flags(:bridge).include?(rank)
        count = 2
        :red
      else
        :white
      end
    end

    def flag_level(rank)
      if rank == "DAIDE"
        :d
      elsif rank == "NAIDE"
        :n
      elsif rank == "FLT"
        :s
      elsif rank == "DFLT"
        :d
      elsif rank == "NFLT"
        :n
      else
        nil
      end
    end

    def flag_count(rank)
      if valid_flags(:command).include?(rank)
        3
      elsif valid_flags(:bridge).include?(rank)
        2
      else
        1
      end
    end

    def flag_type(rank)
      if valid_flags(:squadron).include?(rank)
        :s
      elsif valid_flags(:district).include?(rank)
        :d
      elsif rank == "STFC"
        :stf
      elsif valid_flags(:national).include?(rank)
        :n
      elsif rank == "PORTCAP"
        :pc
      elsif rank == "FLEETCAP"
        :fc
      elsif rank == "DAIDE"
        :a
      elsif rank == "NAIDE"
        :a
      elsif rank == "FLT"
        :f
      elsif rank == "DFLT"
        :f
      elsif rank == "NFLT"
        :f
      end
    end
  end
end