#!/usr/bin/python
__author__='Semyon Teplisky'

import functools
import pandas as pd
import numpy as np

raw_data = [{'campaign_id':1111,'medium_id':'msn','campaign_name': 'viral #1', 'clicks':100, 'ctr':0.7},
            {'campaign_id':1111,'medium_id':'aol','campaign_name': 'viral #1', 'clicks':250, 'ctr':0.4},
            {'campaign_id':1111,'medium_id':'google','campaign_name': 'viral #1', 'clicks':500, 'ctr':0.1}]

data = pd.DataFrame(raw_data)


# Option 1 Advanced with functools
def wavg(val, df, weight):
    try:
        w = df.ix[val.index][weight]
        return (val * w).sum() / w.sum()
    except ZeroDivisionError:
        return val.mean()

# Binding df to function with functools
fwavg = functools.partial(wavg, df=data, weight='clicks')

gdata = data.groupby(['campaign_id']).agg({"conversions":np.sum, "impressions":np.sum,
                                                                 "spend":np.sum,"clicks":np.sum, "ctr":fwavg}).reset_index()
gdata.fillna(0.0, inplace=True)
gdata.head()

# Option 2 Math Workaround
data['ctr'] = data['clicks'] * data['ctr']

gdata = data.groupby(['campaign_id']).agg({"conversions":np.sum, "impressions":np.sum,
                                                                 "spend":np.sum,"clicks":np.sum, "ctr":np.sum}).reset_index()
gdata['ctr'] = gdata['ctr'] / gdata['clicks']
gdata.head()

# Option 3 Two DF
def wavg(group, avg_name, weight_name):
    val = group[avg_name]
    w = group[weight_name]
    try:
        return (val * w).sum() / w.sum()
    except ZeroDivisionError:
        return val.mean()

gdata = data.groupby(['campaign_id'])
data_ctr = gdata.apply(wavg, "ctr", "clicks")
data_meta = gdata.agg({"conversions":np.sum, "impressions":np.sum, "spend":np.sum,"clicks":np.sum})
gdata = pd.merge(data_meta, data_ctr, on='campaign_id')
gdata.head()