"""
Script to extract the total amount of MJ of the different fluids of BuildCraft 8+.
"""
import re
import argparse
import urllib.request


DEFAULT_URL = 'https://raw.githubusercontent.com/BuildCraft/BuildCraft/8.0.x/common/' \
              'buildcraft/energy/BCEnergyRecipes.java'


def _parse_total_power(code):
    # read the constants in the file
    constants = {}
    for x in re.findall(r'final int (.*?) = (\d*)', code):
        constant, value = x
        if constant == 'TIME_BASE':
            value = int(value) * 1000
        constants[constant] = int(value)

    # read the assigned values in the function
    amount_diffs = {}
    for x in re.findall(r'add(Dirty)?Fuel\((.*?), (.*?), (\d*?)\)', code):
        _, fluid, amountDiff, multiplier = x
        if amountDiff not in constants:
            raise ValueError('The source code can\'t be read. It should have changed')
        amount_diffs[fluid] = constants[amountDiff]

    # print the total power of each fluid:

    # total power = totalTime * powerPerCycle = multiplier * MjAPI.MJ * (TIME_BASE / multiplier / amountDiff) <=>
    # total power = MjAPI.MJ * TIME_BASE / amountDiff

    total_power = {}
    for fluid in amount_diffs:
        total_power[fluid] = constants['TIME_BASE'] // amount_diffs[fluid]

    return total_power


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--url",
                        help="The url of the file that contains the BC energy recipes, "
                             "BCEnergyRecipes.java. Something starting with https://raw.githubusercontent",
                        type=str)
    parser.add_argument("--file",
                        help="The location of the file that contains the BC energy recipes, "
                             "BCEnergyRecipes.java.",
                        type=argparse.FileType('r', encoding='UTF-8'))

    args = parser.parse_args()

    if args.file is None:
        # read the content of the relevant source
        if args.url is None:
            url = DEFAULT_URL
        else:
            url = args.url

        with urllib.request.urlopen(url) as f:
            code = f.read().decode('utf-8')
    else:
        code = args.file.read()

    total_power = _parse_total_power(code)
    print('Total power (MJ/B) of each of the BuildCraft fluids:')
    for fluid in total_power:
        print('%s = %d' % (fluid, total_power[fluid]))


if __name__ == '__main__':
    main()