#!/usr/bin/python
import base64
import Image
import os

# image_list = [{filname:'...', anchor: {top, left}}, ...]
def merge(image_list, output_file = None):
    if type(image_list) is not list:
        raise Exception('first argument is not a list')
    if len(image_list) < 2:
        raise Exception('image_list to short')
    if not output_file:
        filename_result = ''
        for image in image_list:
            filename_result += image['filename']
        filename_result = base64.encodestring(filename_result)
        filename_result += '.png'
    else:
        filename_result = output_file
    print(filename_result)
    if not os.path.isfile(filename_result):
        image_result = Image.open(image_list[0]['filename'])
        image_result.show()
        for image in image_list:
            image_result.paste(image['filename'], (image['anchor']['top'], \
                        image['anchor']['top']), image['filename'])
        image_result.save(filename_result)
    return filename_result

def sample():
    return [{'filename':'marker_base.png',
             'anchor':{
                       'top':0,
                       'left':0
                      }
            },
            {'filename':'overlay_education.png',
             'anchor':{
                       'top':0,
                       'left':0
                      }
            },]