# -*- coding: utf-8 -*-
#
#    Copyright © 2024 Simon Forman
#
#    This file is part of game
#
#    game is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    game is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with game.  If not see <http://www.gnu.org/licenses/>.
#
import data


def turn():
    conn = data.open_db()
    cursor = conn.cursor()
    life_grows(cursor)
    population_grows(cursor)
    industry_produces()
    vessels_move()
    conn.commit()
    data.close_db()


BIO_GROWTH = 0.03
POP_GROWTH = 0.0125


def life_grows(db_cursor):
    print('life_grows')
    db_cursor.execute(
        '''
        select id, bio, bio_capacity from planets
        where bio > 0 and bio < bio_capacity
        '''
    )
    planets = list(db_cursor.fetchall())
    # Get all the results before updating some in this loop.
    for planet_id, bio, bio_capacity in planets:

        # We add at least one unit of population per turn.
        new_bio = round(bio * BIO_GROWTH) or 1

        available_capacity = bio_capacity - bio

        if new_bio > available_capacity:
            excess_bio = new_bio - available_capacity
            new_bio = available_capacity

        else:
            excess_bio = 0

        bio += new_bio
        assert bio <= bio_capacity
        print(
            f'setting planet {planet_id} bio to {bio} increment of {new_bio}, excess_bio {excess_bio}'
        )
        db_cursor.execute('update planets set bio = ? where id = ?', (bio, planet_id))


def population_grows(db_cursor):
    print('population_grows')
    db_cursor.execute(
        '''
        select populations.id, populations.pop, planets.id, planets.bio
        from populations join planets
        on populations.planet = planets.id
        and populations.home_star = planets.star
        '''
    )
    # People are only legally allowed to reproduce in their home
    # stellar systems.
    pops = list(db_cursor.fetchall())
    for pop_id, pop, planet_id, bio in pops:
        if pop > bio:
            # famine and death!  Woe!
            print(f'WARNING population crash on planet {planet_id}!')
            pop = bio >> 1
            bio //= 10
        else:
            # Everyone eats.
            bio -= pop
            pop += round(pop * POP_GROWTH)
        print(f'population {pop_id} of planet {planet_id} is now {pop}, bio is {bio}')
        db_cursor.execute('update planets set bio = ? where id = ?', (bio, planet_id))
        db_cursor.execute('update populations set pop = ? where id = ?', (pop, pop_id))


def industry_produces():
    print('industry_produces')


def vessels_move():
    print('vessels_move')


if __name__ == '__main__':
    turn()