using System.Threading.Tasks;
using Content.Server.Interaction;
using Content.Server.NPC.Systems;
using Content.Shared.MobState;
using Content.Shared.MobState.Components;
using Robust.Shared.Map;

namespace Content.Server.NPC.HTN.PrimitiveTasks.Operators;

public abstract class NPCCombatOperator : HTNOperator
{
    [Dependency] protected readonly IEntityManager EntManager = default!;
    private AiFactionTagSystem _tags = default!;
    protected InteractionSystem Interaction = default!;

    [ViewVariables, DataField("key")] public string Key = "CombatTarget";

    /// <summary>
    /// The EntityCoordinates of the specified target.
    /// </summary>
    [ViewVariables, DataField("keyCoordinates")]
    public string KeyCoordinates = "CombatTargetCoordinates";

    public override void Initialize(IEntitySystemManager sysManager)
    {
        base.Initialize(sysManager);
        _tags = sysManager.GetEntitySystem<AiFactionTagSystem>();
        Interaction = sysManager.GetEntitySystem<InteractionSystem>();
    }

    public override async Task<(bool Valid, Dictionary<string, object>? Effects)> Plan(NPCBlackboard blackboard)
    {
        var targets = GetTargets(blackboard);

        if (targets.Count == 0)
        {
            return (false, null);
        }

        // TODO: Need some level of rng in ratings (outside of continuing to attack the same target)
        var selectedTarget = targets[0].Entity;

        var effects = new Dictionary<string, object>()
        {
            {Key, selectedTarget},
            {KeyCoordinates, new EntityCoordinates(selectedTarget, Vector2.Zero)}
        };

        return (true, effects);
    }

    private List<(EntityUid Entity, float Rating)> GetTargets(NPCBlackboard blackboard)
    {
        var owner = blackboard.GetValue<EntityUid>(NPCBlackboard.Owner);
        var radius = blackboard.GetValueOrDefault<float>(NPCBlackboard.VisionRadius, EntManager);
        var targets = new List<(EntityUid Entity, float Rating)>();

        blackboard.TryGetValue<EntityUid>(Key, out var existingTarget);
        var xformQuery = EntManager.GetEntityQuery<TransformComponent>();
        var mobQuery = EntManager.GetEntityQuery<MobStateComponent>();
        var canMove = blackboard.GetValueOrDefault<bool>(NPCBlackboard.CanMove, EntManager);

        // TODO: Need a perception system instead
        foreach (var target in _tags
                     .GetNearbyHostiles(owner, radius))
        {
            if (mobQuery.TryGetComponent(target, out var mobState) &&
                mobState.CurrentState > DamageState.Alive)
            {
                continue;
            }

            targets.Add((target, GetRating(blackboard, target, existingTarget, canMove, xformQuery)));
        }

        targets.Sort((x, y) => y.Rating.CompareTo(x.Rating));
        return targets;
    }

    protected abstract float GetRating(NPCBlackboard blackboard, EntityUid uid, EntityUid existingTarget, bool canMove,
        EntityQuery<TransformComponent> xformQuery);
}