import re
import os
import numpy as np

from datalayers.datasources.tiff_layer import TiffLayer

class WorldpopPopc(TiffLayer):

    def __init__(self):
        super().__init__()

        self.precision = 0
        self.format_suffix = 'entities'

    def download(self):
        for year in range(2010, 2020+1):
            url = f"https://data.worldpop.org/GIS/Population/Global_2000_2020/{year}/GHA/gha_ppp_{year}_UNadj.tif"
            self._save_url_to_file(url)

    def consume(self, file, band, shape):
        x = re.search(r'[0-9]+', os.path.basename(file))
        year = int(x[0])

        self.rows.append({
            'year':     year,
            'shape_id': shape.id,
            'value':    np.nansum(band)
        })