defmodule Doex.Cli.Main do
  use FnExpr
  alias Doex.Io.Shell

  def main(argv) do
    argv
    |> parse
    |> run
  end

  def run({:doex, []}) do
    Shell.info("doex v" <> Doex.version())
    Shell.info("doex is a API client for Digital Ocean's API v2.")
    Shell.newline()

    Shell.info("Available tasks:")
    Shell.newline()
    # Run `mix help --search doex.` to get this output
    # and paste here, replacing `mix doex.` with just `doex `

    Shell.info(
      "#{Shell.cmd("doex block")}            # Block the command line until a condition is met"
    )

    Shell.info("#{Shell.cmd("doex config")}           # Reads, updates or deletes Doex config")

    Shell.info(
      "#{Shell.cmd("doex delete")}           # Execute a Digital Ocean API DELETE request"
    )

    Shell.info("#{Shell.cmd("doex droplets.create")}  # Create a droplet on Digital Ocean")

    Shell.info(
      "#{Shell.cmd("doex droplets.id")}      # Locate a droplet ID, by name or tag (--tag)"
    )

    Shell.info("#{Shell.cmd("doex droplets.tag")}     # Tag a droplet.")
    Shell.info("#{Shell.cmd("doex get")}              # Execute a Digital Ocean API GET request")

    Shell.info(
      "#{Shell.cmd("doex id")}               # Locate a ID of a resource, by name or tag (--tag)"
    )

    Shell.info(
      "#{Shell.cmd("doex imagelets.create")} # Create a DitigalOcean snapshot based on available templates"
    )

    Shell.info("#{Shell.cmd("doex init")}             # Initialize your doex config")
    Shell.info("#{Shell.cmd("doex ip")}               # Get the IP of a droplet")
    Shell.info("#{Shell.cmd("doex ls")}               # List your resources.")
    Shell.info("#{Shell.cmd("doex post")}             # Execute a Digital Ocean API POST request")
    Shell.info("#{Shell.cmd("doex put")}              # Execute a Digital Ocean API PUT request")

    Shell.info(
      "#{Shell.cmd("doex scp")}              # Secure copy a file from <src> to your droplet's <target>"
    )

    Shell.info(
      "#{Shell.cmd("doex snapshots.create")} # Creates a snapshot of an existing Digital Ocean droplet"
    )

    Shell.info("#{Shell.cmd("doex ssh")}              # Execute a command on your droplet")

    Shell.info(
      "#{Shell.cmd("doex ssh.hostkey")}      # Add the droplet hostkey to the executing server"
    )

    Shell.newline()

    Shell.info("Further information can be found here:")
    Shell.info("  -- https://hex.pm/packages/doex")
    Shell.info("  -- https://github.com/aforward/doex")
    Shell.newline()
  end

  def run({:doex, [cmd | args]}), do: run({:unknown, cmd, args})

  # TODO: consider moving to macro expansion
  def run({:config, args}), do: Doex.Cli.Config.run(args)
  def run({:id, args}), do: Doex.Cli.Id.run(args)
  def run({:ip, args}), do: Doex.Cli.Ip.run(args)
  def run({:ls, args}), do: Doex.Cli.Ls.run(args)
  def run({:ssh, args}), do: Doex.Cli.Ssh.run(args)
  def run({:ssh_hostkey, args}), do: Doex.Cli.Ssh.Hostkey.run(args)
  def run({:scp, args}), do: Doex.Cli.Scp.run(args)
  def run({:droplets_id, args}), do: Doex.Cli.Droplets.Id.run(args)
  def run({:droplets_tag, args}), do: Doex.Cli.Droplets.Tag.run(args)
  def run({:droplets_create, args}), do: Doex.Cli.Droplets.Create.run(args)
  def run({:floating_ip_id, args}), do: Doex.Cli.FloatingIp.Id.run(args)
  def run({:floating_ip_reassign, args}), do: Doex.Cli.FloatingIp.Reassign.run(args)
  def run({:snapshots_create, args}), do: Doex.Cli.Snapshots.Create.run(args)
  def run({:imagelets_create, args}), do: Doex.Cli.Imagelets.Create.run(args)
  def run({:init, args}), do: Doex.Cli.Init.run(args)
  def run({:get, args}), do: Doex.Cli.Get.run(args)
  def run({:post, args}), do: Doex.Cli.Post.run(args)
  def run({:put, args}), do: Doex.Cli.Put.run(args)
  def run({:delete, args}), do: Doex.Cli.Delete.run(args)
  def run({:block, args}), do: Doex.Cli.Block.run(args)

  def run({:unknown, "dexter", _args}) do
    Shell.error("You following me?")
    Shell.newline()
  end

  def run({:unknown, "doakes", _args}) do
    Shell.error("Surprise muthaf*cka.")
    Shell.newline()
  end

  def run({:unknown, unknown_cmd, _args}) do
    Shell.error("We couldn't process #{unknown_cmd}, so kindly check your spelling and try again")
    Shell.newline()
    run({:doex, []})
  end

  def run({cmd, args}), do: run({:unknown, cmd, args})

  defp parse([]), do: {:doex, []}

  defp parse([subcommand | subargs]) do
    subcommand
    |> String.replace(".", "_")
    |> String.to_atom()
    |> invoke({&1, subargs})
  end
end