# indie:lang_version = 5
from indie import indicator, param, plot, color
from indie.algorithms import Lowest, Highest, Donchian


@indicator('DC', overlay_main_pane=True)  # Donchian Channels
@param.int('length', default=20, min=1)
@plot.line('lower', color=color.BLUE, title='Lower')
@plot.line(color=color.RED, title='Basis')
@plot.line('upper', color=color.BLUE, title='Upper')
@plot.fill('lower', 'upper', color=color.AQUA(0.05), title='Background')
def Main(self, length):
    lower = Lowest.new(self.low, length)
    upper = Highest.new(self.high, length)
    basis = Donchian.new(length)
    return lower[0], basis[0], upper[0], plot.Fill()