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<!-- language: lang-java -->
    package player;

    import java.lang.Math.*;
    import java.util.Set;
    import java.util.HashSet;
    import zombie.*;
    import static zombie.Constants.*;

    public class Coward implements Player {

        private static final Set<PlayerId> killed = new HashSet<>();
        private static final Set<PlayerId> looted = new HashSet<>();

        @Override
        public Action doTurn(PlayerContext context) {

            PlayerId[][] field = context.getPlayField();

            // Panic and shoot
            if (context.getBullets() > 0) {
                int distEnemy = VISION_WIDTH;
                int distZombie = VISION_WIDTH;
                PlayerId targetEnemy = null;
                PlayerId targetZombie = null;
                for (int x = CENTRE_OF_VISION - SHOOT_RANGE; x <= CENTRE_OF_VISION + SHOOT_RANGE; x++) {
                    for (int y = CENTRE_OF_VISION - SHOOT_RANGE; y <= CENTRE_OF_VISION + SHOOT_RANGE; y++) {
                        PlayerId player = field[x][y];
                        if (player != null && !killed.contains(player)) {
                            int dist = getDistance(x, y);
                            if (player.getName().equals("Zombie")) {
                                if( dist < distZombie ) {
                                    distZombie = dist;
                                    targetZombie = player;
                                }
                            } else if (isEnemy(player.getName()) && dist <= distEnemy ) {
                                distEnemy = dist;
                                targetEnemy = field[x][y];
                            }
                        }
                    }
                }

                if (targetZombie != null && distZombie <= 3) {
                    killed.add(targetZombie);
                    return new Shoot( targetZombie );
                } else if (targetEnemy != null && distEnemy <= 5 ) {
                    killed.add(targetEnemy);
                    return new Shoot( targetEnemy );
                }
            }

            // Run away
            int bestScore = -10000000;
            Move bestMove = Move.randomMove();

            for( int x = -1; x <= 1; x++ ) {
                for( int y = -1; y <= 1; y++ ) {
                    PlayerId center = field[CENTRE_OF_VISION+x][CENTRE_OF_VISION+y];
                    if( center != null && !looted.contains(center) && center.getName().equals("DeadBody")) {
                        looted.add(center);
                    }
                    if( center == null ) {
                        int thisScore = 0;
                        for( int xx = CENTRE_OF_VISION+x-VISION_RANGE+1; xx < CENTRE_OF_VISION+x+VISION_RANGE; xx++ ) {
                            for( int yy = CENTRE_OF_VISION+y-VISION_RANGE+1; yy < CENTRE_OF_VISION+y+VISION_RANGE; yy++ ) {
                                PlayerId player = field[xx][yy];
                                if( player != null) {
                                    int dist = getDistance(xx-x,yy-y);

                                    if( player.getName().equals("Coward")) { // Prefer lose groups
                                        if( dist >= 3 && dist <= 6 ) {
                                            thisScore += 32;
                                        } else if( dist > 3 ) {
                                            thisScore += 16;
                                        }
                                    } else if( player.getName().equals("DeadBody")) { // Visit dead bodies on the route
                                        if( !looted.contains(player)) {
                                            thisScore += 32*(VISION_RANGE-dist);
                                        }
                                    } else if( player.getName().equals("Zombie")) { // Avoid zombies
                                        if( dist <= 2 ) {
                                            thisScore -= 10000;
                                        } else if( dist <= 3 ) {
                                            thisScore -= 1000;
                                        } else if( dist <= 4 ) {
                                            thisScore -= 100;
                                        }
                                    } else if( isEnemy(player.getName())) { // Avoid strangers
                                        if( dist == 7 ) {
                                            thisScore -= 100;
                                        } else if( dist <= 6 ) {
                                            thisScore -= 1000;
                                        }
                                    }
                                }
                            }
                        }
                        if( thisScore > bestScore ) {
                            bestScore = thisScore;
                            bestMove = Move.inDirection( x, y );
                        }
                    }
                }
            }

            return bestMove;
        }

        private boolean isEnemy(String name) {
            switch (name) {
                case "Coward":
                case "DeadBody":
                case "GordonFreeman":
                case "EmoWolfWithAGun":
                case "HuddleWolf":
                case "ThePriest":
                case "Shotguneer":
                    return false;
                default:
                    return true;
            }
        }

        private int getDistance(int x, int y) {
            return Math.max(Math.abs(CENTRE_OF_VISION - x), Math.abs(CENTRE_OF_VISION - y));
        }
    }