# indie:lang_version = 5
from indie import indicator, format, param, source, level, color, plot
from indie.algorithms import Ema, Sma
from indie.math import divide


@indicator('PPO', format=format.PRICE)  # Price Oscillator
@param.int('short_len', default=10, min=1, title='Short Length')
@param.int('long_len', default=21, min=1, title='Long Length')
@param.source('src', default=source.CLOSE, title='Source')
@param.bool('exponential', default=False)
@level(0, line_color=color.GRAY, title='Zero')
@plot.line(color=color.GREEN, title='OSC')
def Main(self, short_len, long_len, src, exponential):
    short, long = 0.0, 0.0
    if exponential:
        short = Ema.new(src, short_len)[0]
        long = Ema.new(src, long_len)[0]
    else:
        short = Sma.new(src, short_len)[0]
        long = Sma.new(src, long_len)[0]
    return 100 * divide(short - long, long)