package bot;

import java.util.*;

public class EscapeBot extends Bot {
    private boolean rocketFound;
    private int roverX;
    private int roverY;

    public EscapeBot(String[] args) {
        super(args);
        this.rocketFound = false;
        this.roverX = -1; // Startposition des Rovers ist unbekannt
        this.roverY = -1;
    }

    @Override
    protected char nextMove(View view) throws Exception {
        if (rocketFound) {
            System.out.println("Rakete gefunden! Rover kehrt zurück.");
            return 'V'; // Rückwärts bewegen
        }

        if (roverX == -1 || roverY == -1) {
            for (int y = 0; y < view.width; y++) {
                for (int x = 0; x < view.width; x++) {
                    char cell = view.data.charAt(y * view.width + x);
                    if (cell == 'A') {
                        roverX = x;
                        roverY = y;
                    }
                }
            }
        }

        char[][] grid = new char[view.width][view.width];
        for (int y = 0; y < view.width; y++) {
            for (int x = 0; x < view.width; x++) {
                grid[y][x] = view.data.charAt(y * view.width + x);
            }
        }

        List<Node> path = aStarSearch(grid, roverX, roverY);

        if (path != null && !path.isEmpty()) {
            Node nextNode = path.get(0);
            if (nextNode.x > roverX) {
                roverX++;
                return 'd'; // Nach rechts bewegen
            } else if (nextNode.x < roverX) {
                roverX--;
                return 'a'; // Nach links bewegen
            } else if (nextNode.y > roverY) {
                roverY++;
                return '^'; // Vorwärts bewegen
            } else if (nextNode.y < roverY) {
                roverY--;
                return 'V'; // Rückwärts bewegen
            }
        }

        return '^'; // Standardbewegung, wenn keine Richtung gefunden wurde
    }

    private List<Node> aStarSearch(char[][] grid, int startX, int startY) {
        PriorityQueue<Node> openList = new PriorityQueue<>(Comparator.comparingInt(a -> a.f));
        Set<Node> closedSet = new HashSet<>();
        Map<Node, Node> cameFrom = new HashMap<>();
        Map<Node, Integer> gScore = new HashMap<>();
        Map<Node, Integer> fScore = new HashMap<>();

        Node startNode = new Node(startX, startY);
        openList.add(startNode);
        gScore.put(startNode, 0);
        fScore.put(startNode, heuristic(startNode));

        while (!openList.isEmpty()) {
            Node current = openList.poll();

            if (grid[current.y][current.x] == 'o') {
                return reconstructPath(cameFrom, current);
            }

            closedSet.add(current);

            for (Node neighbor : getNeighbors(current, grid)) {
                if (closedSet.contains(neighbor)) {
                    continue;
                }

                int tentativeGScore = gScore.getOrDefault(current, Integer.MAX_VALUE) + 1;

                if (!openList.contains(neighbor) || tentativeGScore < gScore.getOrDefault(neighbor, Integer.MAX_VALUE)) {
                    cameFrom.put(neighbor, current);
                    gScore.put(neighbor, tentativeGScore);
                    fScore.put(neighbor, tentativeGScore + heuristic(neighbor));

                    if (!openList.contains(neighbor)) {
                        openList.add(neighbor);
                    }
                }
            }
        }

        return null; // Kein Weg gefunden
    }

    private List<Node> getNeighbors(Node node, char[][] grid) {
        List<Node> neighbors = new ArrayList<>();

        int[][] directions = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}}; // Rechts, Links, Unten, Oben

        for (int[] dir : directions) {
            int newX = node.x + dir[0];
            int newY = node.y + dir[1];

            if (newX >= 0 && newX < grid.length && newY >= 0 && newY < grid.length &&
                    grid[newY][newX] != '#') {
                neighbors.add(new Node(newX, newY));
            }
        }

        return neighbors;
    }

    private List<Node> reconstructPath(Map<Node, Node> cameFrom, Node current) {
        List<Node> path = new ArrayList<>();
        path.add(current);
        while (cameFrom.containsKey(current)) {
            current = cameFrom.get(current);
            path.add(current);
        }
        Collections.reverse(path);
        return path;
    }

    private int heuristic(Node node) {
        // Verwenden Sie die Manhattan-Distanz als Heuristik, um die tatsächliche Entfernung zum Ziel zu schätzen
        return Math.abs(node.x - roverX) + Math.abs(node.y - roverY);
    }

    private static class Node {
        int x;
        int y;
        int f;

        Node(int x, int y) {
            this.x = x;
            this.y = y;
            this.f = 0;
        }

        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Node node = (Node) o;
            return x == node.x && y == node.y;
        }

        @Override
        public int hashCode() {
            return Objects.hash(x, y);
        }
    }

    public static void main(String[] args) {
        EscapeBot escapeBot = new EscapeBot(args);
        escapeBot.run();
    }
}