import random

import robots

from robots.algorithms import distance_relaxer
from robots.constants import City
from robots.utils import add_spawns

class CaptureSpawns(object):
    def __init__(self, variance=0.1):
        self.iterations = 10
        self.variance = variance

    def __call__(self, whoami, state):
        my_robots = state.robots_by_player[whoami]

        # Create a distance matrix.
        distances = []
        for y, row in enumerate(state.cities):
            output = []
            for x, city in enumerate(row):
                d = float('inf')
                if city == City.FACTORY:
                    if state.allegiances.get((x, y)) != whoami:
                        d = 0
                elif city == City.GHOST:
                    d = None
                output.append(d)
            distances.append(output)

        # Find the shortest path to a target from each cell.
        predecessors = distance_relaxer(distances)

        # Direct the robots to follow those paths.
        results = []
        for x, y, energy in my_robots:
            if random.random() < self.variance:
                result = random.choice('ULDR')
            elif predecessors[y][x]:
                result = random.choice(predecessors[y][x])
            elif state.allegiances.get((x, y)) != whoami:
                result = 'P'
            else:
                result = random.choice('UDLR')
            results.append(result)
        return results

if __name__ == '__main__':
    server = robots.Server()
    server.SERVER_NAME = 'Capturer Server'
    server.add_bot(CaptureSpawns, 'Capture')
    server.run()