# indie:lang_version = 5
from indie import indicator, param, source, plot, color
from indie.algorithms import Ema


@indicator('EMA', overlay_main_pane=True)  # Moving Average Exponential
@param.int('length', default=9, min=1)
@param.source('src', default=source.CLOSE, title='Source')
@param.int('offset', default=0, min=-500, max=500, title='Offset')
@plot.line(color=color.BLUE)
def Main(self, length, src, offset):
    ema = Ema.new(src, length)
    return plot.Line(ema[0], offset=offset)
    # TODO: implement smoothing when display.none is supported