defmodule ToweropsWeb.Plugs.MarkdownNegotiation do
  @moduledoc false

  import Plug.Conn

  @markdown_content %{
    "/" => """
    # TowerOps

    Network monitoring and alerting platform built for WISP and ISP operators.

    See the business impact of every network event.

    ## Features

    - Real-time network monitoring
    - Subscriber impact analysis
    - Revenue impact tracking
    - Equipment management
    - Multi-site support

    ## Get Started

    - [Register](/users/register)
    - [Log In](/users/log-in)
    - [API Documentation](/docs/api)
    - [Privacy Policy](/privacy)
    - [Terms of Service](/terms)
    """,
    "/privacy" =>
      "# Privacy Policy\n\nVisit [towerops.net/privacy](https://towerops.net/privacy) for the full privacy policy.\n",
    "/terms" =>
      "# Terms of Service\n\nVisit [towerops.net/terms](https://towerops.net/terms) for the full terms of service.\n"
  }

  def init(opts), do: opts

  def call(conn, _opts) do
    if accepts_markdown?(conn) do
      case Map.get(@markdown_content, conn.request_path) do
        nil -> conn
        markdown -> send_markdown(conn, markdown)
      end
    else
      conn
    end
  end

  defp accepts_markdown?(conn) do
    conn
    |> get_req_header("accept")
    |> Enum.any?(&String.contains?(&1, "text/markdown"))
  end

  defp send_markdown(conn, content) do
    conn
    |> put_resp_content_type("text/markdown")
    |> send_resp(200, content)
    |> halt()
  end
end