from sage.all import *

# Save the default so that we can call it within mjo_plot.
sage_plot = plot

def mjo_plot(*args, **kwargs):
    """
    Replacement for the default plot function.

     - Use the 'latex' tick formatter.

     - If there's a legend, set the background color to 'white' and
       give it a drop shadow.

    """
    plot_opts = { 'tick_formatter': 'latex' }
    
    legend_opts = { 'back_color': 'white',
                    'shadow': True }

    # Merge the user's plot options with mine. The ones given as
    # kwargs should override the defaults!
    plot_opts.update(kwargs)
    kwargs = plot_opts
    p = sage_plot(*args, **kwargs)
    p.set_legend_options(**legend_opts)
    return p

# Replace both the global `plot` and the one in the module. I am
# unclear about why this is necessary, and don't care too much.
sage.plot.plot.plot = mjo_plot
plot = mjo_plot