gulib

defmodule Gulib.Float do

  def ceiling(float) do
    t = trunc(float)

    case float - t do
      neg when neg < 0 -> t
      pos when pos > 0 -> t + 1
      _ -> t
    end
  end

  def to_binary(value, opts \\ []) do
    :erlang.float_to_binary(value, opts)
  end

  def parse(x) when is_nil(x), do: 0.0
  def parse(x)  when is_float(x), do: x
  def parse(x) when is_integer(x) do
    "#{x}.0" |> String.to_float
  end
  def parse(x) when is_binary(x) or is_bitstring(x) do
    try do
      x = x |> String.trim 

      negative = x |> String.starts_with?("-")

      x =
        if negative do
          String.trim_leading(x, "-")
        else
          x
        end
        |> String.split(~r{[^0-9.]})
        |> List.first
        |> String.split(".")
        |> Enum.filter(fn(i) -> 
          i != ""
        end)

      value = "#{Enum.at(x, 0)}.#{Enum.at(x, 1) || 0}" |> String.to_float

      if negative, do: -value, else: value
    rescue
      ArgumentError -> 0.0
    end
  end
  def parse(x) when is_atom(x) do
    try do
      x |> Atom.to_string |> parse
    rescue
      ArgumentError -> 0.0
    end
  end

end