namespace MazeGen
{
    /// <summary>
    /// Declares a fight with monsters in the current room if the threat level is acceptable.
    /// Uses a health-aware retreat threshold: lower health = more defensive.
    /// </summary>
    public class DeclareFightDecision : AgentDecision
    {
        private CombatDirector _director;
        private float _retreatThreshold;

        public override string DecisionName => "Declare Fight";

        public DeclareFightDecision(CombatDirector director, float retreatThreshold)
        {
            _director = director;
            _retreatThreshold = retreatThreshold;
        }

        public override bool CanExecute(MazeAgent agent)
        {
            if (agent == null || _director == null) return false;
            if (agent.IsEngaged) return false;

            Room room = agent.CurrentRoom;
            if (room == null || room.Encounter == null || !room.Encounter.HasLivingMonsters)
                return false;

            // Already failed here before
            if (agent.HasFledFrom(room.Id))
                return false;

            // Would we accept this threat level?
            float threat = room.Encounter.GetPerceivedChallengeRating(agent.CharacterSheet);
            float effectiveThreshold = GetEffectiveReteatThreshold(agent);
            return threat <= effectiveThreshold;
        }

        public override bool Execute(MazeAgent agent)
        {
            Room room = agent.CurrentRoom;
            float threat = room.Encounter.GetPerceivedChallengeRating(agent.CharacterSheet);
            int hostiles = room.Encounter.AliveMonsterCount;

            _director.DeclareFight(room, agent, $"sized up {hostiles} hostile(s) at threat {threat:0.00} and attacked");
            return true;
        }

        public override void Think(MazeAgent agent)
        {
            Room room = agent.CurrentRoom;
            float threat = room.Encounter.GetPerceivedChallengeRating(agent.CharacterSheet);
            float effectiveThreshold = GetEffectiveReteatThreshold(agent);
            int hostiles = room.Encounter.AliveMonsterCount;

            agent.Thoughts.Add(ThoughtKind.Fight,
                $"Peeked: {hostiles} hostile(s), threat {threat:0.00} vs my limit {effectiveThreshold:0.00} - engaging. Fight starts in {_director.JoinWindowSeconds:0.0}s, hopefully someone joins.");
        }

        private float GetEffectiveReteatThreshold(MazeAgent agent)
        {
            CharacterSheet sheet = agent.CharacterSheet;
            float maxHealth = sheet.Stats.MaxHealth;
            if (maxHealth <= 0) return _retreatThreshold;

            float healthPercent = sheet.Stats.CurrentHealth / maxHealth;

            if (healthPercent < 0.3f)
                return _retreatThreshold * 0.5f;
            else if (healthPercent < 0.5f)
            {
                float t = (healthPercent - 0.3f) / 0.2f;
                return UnityEngine.Mathf.Lerp(_retreatThreshold * 0.5f, _retreatThreshold, t);
            }

            return _retreatThreshold;
        }
    }
}