using Godot;
using System;
using System.Collections.Generic;
using System.Linq;

public partial class Enemy : StaticBody2D
{
    [Signal]
    public delegate void DeathEventHandler(Enemy THIS);
    public int _damage = 1, _health = 2, _speed, _visibilityRange = 10;
    public Vector2I _range = Vector2I.Up;
    public float _movement = 0;
    public GridMarker _gridMarker;
    public EnemyController _enemyController;

    public override void _Ready()
    {
        base._Ready();
    }
    public override void _PhysicsProcess(double delta)
    {
        base._PhysicsProcess(delta);
    }

    public void Attack(Commander COMMANDER)
    {
        COMMANDER.TakeDamage(_damage, this);
    }

    public void CounterAttack(Commander COMMANDER)
    {
        
    }

    public List<GridMarker> Pathfinding(GridMarker DESTINATION, bool INCLUDE_SELF = false)
    {
        PriorityQueue<GridMarker, float> queue = new();
        queue.Enqueue(_gridMarker, 0f);
        Dictionary<GridMarker, GridMarker> cameFrom = new();
        Dictionary<GridMarker, float> costSoFar = new();
        cameFrom[_gridMarker] = null;
        costSoFar[_gridMarker] = 0f;
        GridMarker current;
        float newCost, priority;
        while (queue.Count > 0)
        {
            current = queue.Dequeue();

            if (current == DESTINATION)
            {
                break;
            }

            List<GridMarker> neighbors = current.GetMarkersInRange(1.5f);
            for (int j = 0; j < neighbors.Count; j++)
            {
                GridMarker next = neighbors[j];
                if (next._occupant != null)
                {
                    continue;
                }

                newCost = costSoFar[current] + 1;
                if (!costSoFar.TryGetValue(next, out float value) || newCost < value)
                {
                    costSoFar[next] = newCost;
                    priority = newCost;
                    queue.Enqueue(next, priority);
                    cameFrom[next] = current;
                }
            }
            
        }
        
        List<GridMarker> path = new();
        GridMarker pathMarker = DESTINATION;
        if (cameFrom.ContainsKey(pathMarker))
        {
            while (pathMarker != null)
            {
                path.Add(pathMarker);
                pathMarker = cameFrom[pathMarker];
            }
            path.Reverse();
            if (!INCLUDE_SELF)
            {
                path.Remove(_gridMarker);
            }
        }
        return path;
    }

    public void TakeDamage(int DAMAGE, Commander ATTACKER)
    {
        _health -= DAMAGE;
        CounterAttack(ATTACKER);
        if (_health <= 0)
        {
            EmitSignal(SignalName.Death, this);
        }
    }
}