Photon Image service module in Elixir

Image.ex

defmodule JGBSolutions.Image do
  # https://developer.wordpress.com/docs/photon/api/

  @photon_hosts ["i0.wp.com", "i1.wp.com", "i2.wp.com", "i3.wp.com"]

  def get_photon_url(url, opts \\ []) do
    url = Application.get_env(:jgb_solutions, :domain) <> url

    if String.starts_with?(url, "http") do
      url_without_protocol = make_url_without_protocol(url)

      photon_host = Enum.random(@photon_hosts)

      {photon_query, _opts} =
        {"", opts}
        |> width()
        |> height()
        |> crop()
        |> resize()
        |> fit()
        |> ulb()
        |> lb()
        |> filter()
        |> brightness()
        |> contrast()
        |> colorize()
        |> smooth()
        |> zoom()
        |> quality()
        |> strip()

      "https://#{photon_host}/#{url_without_protocol}?#{photon_query}"
    else
      url
    end
  end

  def width({string, %{width: width} = opts}), do: {string <> "&w=#{width}", opts}
  def width(tuple), do: tuple

  def height({string, %{height: height} = opts}), do: {string <> "&h=#{height}", opts}
  def height(tuple), do: tuple

  def crop({string, %{crop: crop} = opts}) do
    %{x: x, y: y, w: w, h: h} = crop
    {string <> "&crop=#{x},#{y},#{w},#{h}", opts}
  end

  def crop(tuple), do: tuple

  def resize({string, %{resize: resize} = opts}) do
    %{width: width, height: height} = resize
    {string <> "&resize=#{width},#{height}", opts}
  end

  def resize(tuple), do: tuple

  def fit({string, %{fit: fit} = opts}) do
    %{width: width, height: height} = fit
    {string <> "&fit=#{width},#{height}", opts}
  end

  def fit(tuple), do: tuple

  def ulb({string, %{ulb: _ulb} = opts}), do: {string <> "&ulb=true", opts}
  def ulb(tuple), do: tuple

  def lb({string, %{lb: lb} = opts}) do
    %{width: width, height: height} = lb
    {string <> "&lb=#{width},#{height}", opts}
  end

  def lb(tuple), do: tuple

  def filter({string, %{filter: filter} = opts}),
    do: {string <> "&filter=#{filter}", opts}

  def filter(tuple), do: tuple

  def brightness({string, %{brightness: brightness} = opts}),
    do: {string <> "&brightness=#{brightness}", opts}

  def brightness(tuple), do: tuple

  def contrast({string, %{contrast: contrast} = opts}),
    do: {string <> "&contrast=#{contrast}", opts}

  def contrast(tuple), do: tuple

  def colorize({string, %{colorize: colorize} = opts}) do
    %{red: red, green: green, blue: blue} = colorize
    {string <> "&colorize=#{red},#{green},#{blue}", opts}
  end

  def colorize(tuple), do: tuple

  def smooth({string, %{smooth: smooth} = opts}), do: {string <> "&smooth=#{smooth}", opts}

  def smooth(tuple), do: tuple

  def zoom({string, %{zoom: zoom} = opts}),
    do: {string <> "&zoom=#{zoom}", opts}

  def zoom(tuple), do: tuple

  def quality({string, %{quality: quality} = opts}),
    do: {string <> "&quality=#{quality}", opts}

  def quality(tuple), do: tuple

  def strip({string, %{strip: strip} = opts}) do
    {string <> "&strip=#{strip}", opts}
  end

  def strip(tuple), do: tuple

  def make_url_without_protocol(domain), do: String.replace(domain, ~r/(^\w+:|^)\/\//, "")
end