/*
 * Copyright (C) 2012-2020 CypherCore <http://github.com/CypherCore>
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

using Framework.Constants;
using Game.Entities;
using Game.Scripting;
using Game.Spells;
using System;

namespace Scripts.Spells.Monk
{
    struct SpellIds
    {
        public const uint CracklingJadeLightningChannel = 117952;
        public const uint CracklingJadeLightningChiProc = 123333;
        public const uint CracklingJadeLightningKnockback = 117962;
        public const uint CracklingJadeLightningKnockbackCd = 117953;
        public const uint ProvokeSingleTarget = 116189;
        public const uint ProvokeAoe = 118635;
        public const uint SoothingMist = 115175;
        public const uint StanceOfTheSpiritedCrane = 154436;
        public const uint StaggerDamageAura = 124255;
        public const uint StaggerHeavy = 124273;
        public const uint StaggerLight = 124275;
        public const uint StaggerModerate = 124274;
        public const uint SurgingMistHeal = 116995;
    }

    [Script] // 117952 - Crackling Jade Lightning
    class spell_monk_crackling_jade_lightning : AuraScript
    {
        public override bool Validate(SpellInfo spellInfo)
        {
            return ValidateSpellInfo(SpellIds.StanceOfTheSpiritedCrane, SpellIds.CracklingJadeLightningChiProc);
        }

        void OnTick(AuraEffect aurEff)
        {
            Unit caster = GetCaster();
            if (caster)
                if (caster.HasAura(SpellIds.StanceOfTheSpiritedCrane))
                    caster.CastSpell(caster, SpellIds.CracklingJadeLightningChiProc, new CastSpellExtraArgs(TriggerCastFlags.FullMask));
        }

        public override void Register()
        {
            OnEffectPeriodic.Add(new EffectPeriodicHandler(OnTick, 0, AuraType.PeriodicDamage));
        }
    }

    [Script] // 117959 - Crackling Jade Lightning
    class spell_monk_crackling_jade_lightning_knockback_proc_aura : AuraScript
    {
        public override bool Validate(SpellInfo spellInfo)
        {
            return ValidateSpellInfo(SpellIds.CracklingJadeLightningKnockback, SpellIds.CracklingJadeLightningKnockbackCd);
        }

        bool CheckProc(ProcEventInfo eventInfo)
        {
            if (GetTarget().HasAura(SpellIds.CracklingJadeLightningKnockbackCd))
                return false;

            if (eventInfo.GetActor().HasAura(SpellIds.CracklingJadeLightningChannel, GetTarget().GetGUID()))
                return false;

            Spell currentChanneledSpell = GetTarget().GetCurrentSpell(CurrentSpellTypes.Channeled);
            if (!currentChanneledSpell || currentChanneledSpell.GetSpellInfo().Id != SpellIds.CracklingJadeLightningChannel)
                return false;

            return true;
        }

        void HandleProc(AuraEffect aurEff, ProcEventInfo eventInfo)
        {
            GetTarget().CastSpell(eventInfo.GetActor(), SpellIds.CracklingJadeLightningKnockback, new CastSpellExtraArgs(TriggerCastFlags.FullMask));
            GetTarget().CastSpell(GetTarget(), SpellIds.CracklingJadeLightningKnockbackCd, new CastSpellExtraArgs(TriggerCastFlags.FullMask));
        }

        public override void Register()
        {
            DoCheckProc.Add(new CheckProcHandler(CheckProc));
            OnEffectProc.Add(new EffectProcHandler(HandleProc, 0, AuraType.Dummy));
        }
    }

    [Script] // 115546 - Provoke
    class spell_monk_provoke : SpellScript
    {
        const uint BlackOxStatusEntry = 61146;

        public override bool Validate(SpellInfo spellInfo)
        {
            if (!spellInfo.GetExplicitTargetMask().HasAnyFlag(SpellCastTargetFlags.UnitMask)) // ensure GetExplTargetUnit() will return something meaningful during CheckCast
                return false;
            return ValidateSpellInfo(SpellIds.ProvokeSingleTarget, SpellIds.ProvokeAoe);
        }

        SpellCastResult CheckExplicitTarget()
        {
            if (GetExplTargetUnit().GetEntry() != BlackOxStatusEntry)
            {
                SpellInfo singleTarget = Global.SpellMgr.GetSpellInfo(SpellIds.ProvokeSingleTarget, GetCastDifficulty());
                SpellCastResult singleTargetExplicitResult = singleTarget.CheckExplicitTarget(GetCaster(), GetExplTargetUnit());
                if (singleTargetExplicitResult != SpellCastResult.SpellCastOk)
                    return singleTargetExplicitResult;
            }
            else if (GetExplTargetUnit().GetOwnerGUID() != GetCaster().GetGUID())
                return SpellCastResult.BadTargets;

            return SpellCastResult.SpellCastOk;
        }

        void HandleDummy(uint effIndex)
        {
            PreventHitDefaultEffect(effIndex);
            if (GetHitUnit().GetEntry() != BlackOxStatusEntry)
                GetCaster().CastSpell(GetHitUnit(), SpellIds.ProvokeSingleTarget, true);
            else
                GetCaster().CastSpell(GetHitUnit(), SpellIds.ProvokeAoe, true);
        }

        public override void Register()
        {
            OnCheckCast.Add(new CheckCastHandler(CheckExplicitTarget));
            OnEffectHitTarget.Add(new EffectHandler(HandleDummy, 0, SpellEffectName.Dummy));
        }
    }

    //static constexpr SpellEffIndex AuraStaggerEffectTick = EFFECT_0;
    //static constexpr SpellEffIndex AuraStaggerEffectTotal = EFFECT_1;

    [Script] // 115069 - Stagger
    class spell_monk_stagger : AuraScript
    {
        public override bool Validate(SpellInfo spellInfo)
        {
            return ValidateSpellInfo(SpellIds.StaggerLight, SpellIds.StaggerModerate, SpellIds.StaggerHeavy);
        }

        void AbsorbNormal(AuraEffect aurEff, DamageInfo dmgInfo, ref uint absorbAmount)
        {
            Absorb(dmgInfo, 1.0f);
        }

        void AbsorbMagic(AuraEffect aurEff, DamageInfo dmgInfo, ref uint absorbAmount)
        {
            AuraEffect effect = GetEffect(4);
            if (effect == null)
                return;

            Absorb(dmgInfo, effect.GetAmount() / 100.0f);
        }

        void Absorb(DamageInfo dmgInfo, float multiplier)
        {
            // Prevent default action (which would remove the aura)
            PreventDefaultAction();

            // make sure damage doesn't come from stagger damage spell SPELL_MONK_STAGGER_DAMAGE_AURA
            SpellInfo dmgSpellInfo = dmgInfo.GetSpellInfo();
            if (dmgSpellInfo != null)
                if (dmgSpellInfo.Id == SpellIds.StaggerDamageAura)
                    return;

            AuraEffect effect = GetEffect(0);
            if (effect == null)
                return;

            Unit target = GetTarget();
            float agility = target.GetStat(Stats.Agility);
            float baseAmount = MathFunctions.CalculatePct(agility, effect.GetAmount());
            float K = Global.DB2Mgr.EvaluateExpectedStat(ExpectedStatType.ArmorConstant, target.GetLevel(), -2, 0, target.GetClass());

            float newAmount = (baseAmount / (baseAmount + K));
            newAmount *= multiplier;

            // Absorb X percentage of the damage
            float absorbAmount = dmgInfo.GetDamage() * newAmount;
            if (absorbAmount > 0)
            {
                dmgInfo.AbsorbDamage((uint)absorbAmount);

                // Cast stagger and make it tick on each tick
                AddAndRefreshStagger(absorbAmount);
            }
        }

        public override void Register()
        {
            OnEffectAbsorb.Add(new EffectAbsorbHandler(AbsorbNormal, 1));
            OnEffectAbsorb.Add(new EffectAbsorbHandler(AbsorbMagic, 2));
        }

        void AddAndRefreshStagger(float amount)
        {
            Unit target = GetTarget();
            Aura auraStagger = FindExistingStaggerEffect(target);
            if (auraStagger != null)
            {
                AuraEffect effStaggerRemaining = auraStagger.GetEffect(1);
                if (effStaggerRemaining == null)
                    return;

                float newAmount = effStaggerRemaining.GetAmount() + amount;
                uint spellId = GetStaggerSpellId(target, newAmount);
                if (spellId == effStaggerRemaining.GetSpellInfo().Id)
                {
                    auraStagger.RefreshDuration();
                    effStaggerRemaining.ChangeAmount((int)newAmount, false, true /* reapply */);
                }
                else
                {
                    // amount changed the stagger type so we need to change the stagger amount (e.g. from medium to light)
                    GetTarget().RemoveAura(auraStagger);
                    AddNewStagger(target, spellId, newAmount);
                }
            }
            else
                AddNewStagger(target, GetStaggerSpellId(target, amount), amount);
        }

        uint GetStaggerSpellId(Unit unit, float amount)
        {
            const float StaggerHeavy = 0.6f;
            const float StaggerModerate = 0.3f;

            float staggerPct = amount / unit.GetMaxHealth();
            return (staggerPct >= StaggerHeavy) ? SpellIds.StaggerHeavy :
                (staggerPct >= StaggerModerate) ? SpellIds.StaggerModerate :
                SpellIds.StaggerLight;
        }

        void AddNewStagger(Unit unit, uint staggerSpellId, float staggerAmount)
        {
            // We only set the total stagger amount. The amount per tick will be set by the stagger spell script
            unit.CastSpell(unit, staggerSpellId, new CastSpellExtraArgs(SpellValueMod.BasePoint1, (int)staggerAmount).SetTriggerFlags(TriggerCastFlags.FullMask));
        }

        public static Aura FindExistingStaggerEffect(Unit unit)
        {
            Aura auraLight = unit.GetAura(SpellIds.StaggerLight);
            if (auraLight != null)
                return auraLight;

            Aura auraModerate = unit.GetAura(SpellIds.StaggerModerate);
            if (auraModerate != null)
                return auraModerate;

            Aura auraHeavy = unit.GetAura(SpellIds.StaggerHeavy);
            if (auraHeavy != null)
                return auraHeavy;

            return null;
        }
    }

    [Script] // 124255 - Stagger - SPELL_MONK_STAGGER_DAMAGE_AURA
    class spell_monk_stagger_damage_aura : AuraScript
    {
        public override bool Validate(SpellInfo spellInfo)
        {
            return ValidateSpellInfo(SpellIds.StaggerLight, SpellIds.StaggerModerate, SpellIds.StaggerHeavy);
        }

        void OnPeriodicDamage(AuraEffect aurEff)
        {
            // Update our light/medium/heavy stagger with the correct stagger amount left
            Aura auraStagger = spell_monk_stagger.FindExistingStaggerEffect(GetTarget());
            if (auraStagger != null)
            {
                AuraEffect auraEff = auraStagger.GetEffect(1);
                if (auraEff != null)
                {
                    float total = auraEff.GetAmount();
                    float tickDamage = aurEff.GetDamage();
                    auraEff.ChangeAmount((int)(total - tickDamage));
                }
            }
        }

        public override void Register()
        {
            OnEffectPeriodic.Add(new EffectPeriodicHandler(OnPeriodicDamage, 0, AuraType.PeriodicDamage));
        }
    }

    [Script] // 124273, 124274, 124275 - Light/Moderate/Heavy Stagger - SPELL_MONK_STAGGER_LIGHT / SPELL_MONK_STAGGER_MODERATE / SPELL_MONK_STAGGER_HEAVY
    class spell_monk_stagger_debuff_aura : AuraScript
    {
        float _period;

        public override bool Load()
        {
            SpellInfo spellInfo = Global.SpellMgr.GetSpellInfo(SpellIds.StaggerDamageAura, GetCastDifficulty());
            SpellEffectInfo effInfo = spellInfo?.GetEffect(0);
            if (effInfo == null)
                return false;

            _period = (float)effInfo.ApplyAuraPeriod;
            return true;
        }

        void OnReapply(AuraEffect aurEff, AuraEffectHandleModes mode)
        {
            // Calculate damage per tick
            float total = aurEff.GetAmount();
            float perTick = total * _period / (float)GetDuration(); // should be same as GetMaxDuration() TODO: verify

            // Set amount on effect for tooltip
            AuraEffect effInfo = GetAura().GetEffect(0);
            if (effInfo != null)
                effInfo.ChangeAmount((int)perTick);

            // Set amount on damage aura (or cast it if needed)
            CastOrChangeTickDamage(perTick);
        }

        void OnRemove(AuraEffect aurEff, AuraEffectHandleModes mode)
        {
            if (mode != AuraEffectHandleModes.Real)
                return;

            // Remove damage aura
            GetTarget().RemoveAura(SpellIds.StaggerDamageAura);
        }

        public override void Register()
        {
            AfterEffectApply.Add(new EffectApplyHandler(OnReapply, 1, AuraType.Dummy, AuraEffectHandleModes.RealOrReapplyMask));
            AfterEffectRemove.Add(new EffectApplyHandler(OnRemove, 1, AuraType.Dummy, AuraEffectHandleModes.Real));
        }

        void CastOrChangeTickDamage(float tickDamage)
        {
            Unit unit = GetTarget();
            Aura auraDamage = unit.GetAura(SpellIds.StaggerDamageAura);
            if (auraDamage == null)
            {
                unit.CastSpell(unit, SpellIds.StaggerDamageAura, true);
                auraDamage = unit.GetAura(SpellIds.StaggerDamageAura);
            }

            if (auraDamage != null)
            {
                AuraEffect eff = auraDamage.GetEffect(0);
                if (eff != null)
                    eff.SetDamage((int)tickDamage);
            }
        }
    }
}