using System.Linq;
using Content.Shared.Mobs.Systems;
using Content.Shared.Mobs;

namespace Content.Shared._Offbrand.Wounds;

public sealed partial class HealthRankingSystem : EntitySystem
{
    [Dependency] private readonly BrainDamageSystem _brainDamage = default!;
    [Dependency] private readonly HeartSystem _heart = default!;
    [Dependency] private readonly MobStateSystem _mobState = default!;
    [Dependency] private readonly PainSystem _pain = default!;
    [Dependency] private readonly ShockThresholdsSystem _shockThresholds = default!;

    private const float PainDeathRatio = 0.5f;
    private const float BrainDeathRatio = 0.3f;
    private const float HeartDeathRatio = 0.2f;

    public float? RankHealth(EntityUid entity, MobState targetMobState)
    {
        if (!HasComp<WoundableComponent>(entity))
            return null;

        if (targetMobState == MobState.Invalid)
            targetMobState = MobState.Critical;

        if (targetMobState == MobState.Alive)
            return 1f;

        if (targetMobState == MobState.Critical)
        {
            if (_heart.IsCritical(entity) || _brainDamage.IsCritical(entity) || _shockThresholds.IsCritical(entity))
                return 0f;

            if (!TryComp<ShockThresholdsComponent>(entity, out var shockThresholds))
                return 1f;

            var dict = shockThresholds.Thresholds;
            var percentageToPainCrit = _pain.GetShock(entity).Float() / dict.Keys.Last().Float();
            return 1f - (Math.Clamp(percentageToPainCrit, 0f, 1f));
        }
        else if (targetMobState == MobState.Dead)
        {
            if (!TryComp<BrainDamageComponent>(entity, out var brainDamage))
                return 1f;

            if (brainDamage.Damage == brainDamage.MaxDamage)
                return 0f;

            if (!TryComp<ShockThresholdsComponent>(entity, out var shockThresholds))
                return 1f;

            if (!TryComp<HeartrateComponent>(entity, out var heartrate))
                return 1f;

            var dict = shockThresholds.Thresholds;
            var percentageToPainCrit = _pain.GetShock(entity).Float() / dict.Keys.Last().Float();
            var painCrit = 1f - (Math.Clamp(percentageToPainCrit, 0f, 1f));

            var heartCrit = heartrate.Running ? 0f : 1f;

            var brainDamageAmt = brainDamage.Damage;
            var maxBrainDamageAmt = brainDamage.MaxDamage;
            var brainDeath = 1f - (Math.Clamp(brainDamageAmt.Float() / maxBrainDamageAmt.Float(), 0f, 1f));

            return Math.Clamp(painCrit * PainDeathRatio + heartCrit * HeartDeathRatio + brainDeath * BrainDeathRatio, 0f, 1f);
        }

        return 1f;
    }

    public bool IsCritical(EntityUid uid)
    {
        return _mobState.IsCritical(uid) || _shockThresholds.IsCritical(uid) || _brainDamage.IsCritical(uid) || _heart.IsCritical(uid);
    }
}