#!/usr/bin/env python

# Intersects two map spreadsheets A0->B and A1->C to A->B, with B overwriting C

import csv

import os.path

import sys

sys.path.append(os.path.dirname(__file__)+"/../lib")

import maps

def main():

    try: _prog_name, map_1_path = sys.argv

    except ValueError:

        raise SystemExit('Usage: '+sys.argv[0]+' <map_0 map_1 [| '+sys.argv[0]

            +' map_2]... >intersect_map')

    # Get map 1

    map_1 = {}

    stream = open(map_1_path, 'rb')

    reader = csv.reader(stream)

    map_1_cols = reader.next()

    for row in reader:

        if row[0] != '': map_1[row[0]] = row

    stream.close()

    # Open map 0

    reader = csv.reader(sys.stdin)

    map_0_cols = reader.next()

    if map_0_cols[0] != map_1_cols[0]: raise SystemExit('Map error: '

        'Map 1 column 0 name doesn\'t match map 0 column 0 name')

    # Add map 0 to map 1, overwriting existing entries

    writer = csv.writer(sys.stdout)

    writer.writerow(maps.merge_mappings(map_1_cols, map_0_cols))

    for row in reader:

        if row[0] != '':

            try: prev = map_1[row[0]]

            except KeyError: pass

            else: writer.writerow(maps.merge_mappings(prev, row))

main()