""" Core Damage & Defense Calculation Engine for FreeExile (PoE2 Spirit). Implements: 1. Deterministic Evasion Entropy to eliminate RNG streaks. 2. Non-linear Path of Exile Armour formula DR = Armour / (Armour + 5 * Dmg). 3. Elemental Resistance mitigation with hard caps and penetration. 4. Ward / Energy Shield pool absorption preceding Life depletion. 5. Boss Stagger / Poise accumulation and damage vulnerability window. """ from __future__ import annotations import math from typing import Dict, List, Optional, Tuple from combat.combat_types import ( AilmentApplication, AilmentType, BossPhase, BossStaggerState, CombatHitResult, CombatantType, DamageChannel, DamagePacket, DefenseSheet, ) class DamageCalculator: """Pure mathematical and server-authoritative combat resolution pipeline.""" @staticmethod def roll_accuracy_vs_evasion( accuracy: float, evasion: float, entropy_pool: int ) -> Tuple[bool, int]: """ Calculates hit chance using PoE deterministic entropy system. Formula: Hit Chance = Accuracy / (Accuracy + (Evasion / 4)^0.8) Clamped between 5% and 95% unless evasion is 0 (100% hit). """ if evasion <= 0.0: return True, entropy_pool acc = max(1.0, accuracy) denominator = acc + math.pow(max(0.0, evasion) / 4.0, 0.8) hit_chance = acc / denominator clamped_chance = min(0.95, max(0.05, hit_chance)) new_entropy = entropy_pool + int(round(clamped_chance * 100.0)) if new_entropy >= 100: return True, new_entropy - 100 return False, new_entropy @staticmethod def calculate_armour_mitigation(armour: float, incoming_phys: float) -> float: """ PoE Non-Linear Armour Damage Reduction (DR): DR = Armour / (Armour + 5.0 * IncomingPhysicalDamage) Capped at 90% (0.90). """ if incoming_phys <= 0.0 or armour <= 0.0: return 0.0 dr = armour / (armour + 5.0 * incoming_phys) return min(0.90, max(0.0, dr)) @staticmethod def calculate_resistance_damage( raw_damage: float, resistance: float, max_cap: float = 0.75, penetration: float = 0.0, ) -> float: """ Elemental & Chaos resistance damage resolution: Effective Res = min(Resistance, MaxCap) - Penetration Floor at -200% (-2.00). """ if raw_damage <= 0.0: return 0.0 effective_res = min(resistance, max_cap) - penetration effective_res = max(-2.00, effective_res) damage_multiplier = 1.0 - effective_res return max(0.0, raw_damage * damage_multiplier) def execute_hit( self, packet: DamagePacket, defense: DefenseSheet, entropy_pool: Optional[int] = None, boss_stagger: Optional[BossStaggerState] = None, force_crit: Optional[bool] = None, ) -> Tuple[CombatHitResult, int]: """Executes a single damage transaction through all defensive layers.""" current_entropy = entropy_pool if entropy_pool is not None else defense.entropy_pool # 1. Huyễn Ảnh Bộ i-Frame Check (Invulnerability Window) if defense.is_in_iframe: return ( CombatHitResult( is_hit=False, is_evaded=True, is_blocked=False, is_critical=False, raw_damage_total=packet.damage_vector.total_raw(), mitigated_damage_by_channel={}, absorbed_by_ward=0.0, damage_to_life=0.0, final_total_damage=0.0, defender_life_remaining=defense.current_life, defender_ward_remaining=defense.current_ward, ), current_entropy, ) # 2. Accuracy vs Evasion Entropy Check is_hit, next_entropy = self.roll_accuracy_vs_evasion( packet.accuracy, defense.evasion_rating, current_entropy ) defense.entropy_pool = next_entropy if not is_hit: return ( CombatHitResult( is_hit=False, is_evaded=True, is_blocked=False, is_critical=False, raw_damage_total=packet.damage_vector.total_raw(), mitigated_damage_by_channel={}, absorbed_by_ward=0.0, damage_to_life=0.0, final_total_damage=0.0, defender_life_remaining=defense.current_life, defender_ward_remaining=defense.current_ward, ), next_entropy, ) # 3. Block / Parry Check if defense.block_chance > 0.0 and defense.block_chance >= 1.0: return ( CombatHitResult( is_hit=False, is_evaded=False, is_blocked=True, is_critical=False, raw_damage_total=packet.damage_vector.total_raw(), mitigated_damage_by_channel={}, absorbed_by_ward=0.0, damage_to_life=0.0, final_total_damage=0.0, defender_life_remaining=defense.current_life, defender_ward_remaining=defense.current_ward, ), next_entropy, ) # 4. Global Damage Scaling & Multipliers global_multiplier = 1.0 + max(-0.90, packet.increased_damage_pct / 100.0) for more_mult in packet.more_damage_multipliers: global_multiplier *= more_mult is_crit = force_crit if force_crit is not None else (packet.crit_chance >= 1.0) if is_crit: global_multiplier *= packet.crit_multiplier if packet.is_aoe and defense.aoe_damage_reduction_pct > 0.0: global_multiplier *= (1.0 - min(0.90, defense.aoe_damage_reduction_pct)) # 5. Channel Mitigation Evaluation mitigated_channels: Dict[DamageChannel, float] = {} # 5a. Physical Armour Mitigation raw_phys = packet.damage_vector.physical * global_multiplier if raw_phys > 0.0: phys_dr = self.calculate_armour_mitigation(defense.armour, raw_phys) mitigated_channels[DamageChannel.PHYSICAL] = raw_phys * (1.0 - phys_dr) # 5b. Elemental & Chaos Resistance Mitigation for ch in [DamageChannel.FIRE, DamageChannel.COLD, DamageChannel.LIGHTNING, DamageChannel.CHAOS]: raw_val = packet.damage_vector.get_channel(ch) * global_multiplier if raw_val > 0.0: res = defense.resistances.get(ch, 0.0) cap = defense.max_resistance_caps.get(ch, 0.75) pen = packet.elemental_penetration.get(ch, 0.0) mitigated_channels[ch] = self.calculate_resistance_damage(raw_val, res, cap, pen) # 6. Global Damage Taken Modifiers (Shock / Stagger / Fortify) total_mitigated = sum(mitigated_channels.values()) taken_mult = defense.damage_taken_multiplier if boss_stagger and boss_stagger.is_staggered: taken_mult *= boss_stagger.stagger_damage_amplification final_damage = total_mitigated * taken_mult # 7. Absorption Order: Ward (Energy Shield) -> Life absorbed_ward = 0.0 damage_to_life = final_damage if defense.current_ward > 0.0: if defense.current_ward >= final_damage: absorbed_ward = final_damage defense.current_ward -= final_damage damage_to_life = 0.0 else: absorbed_ward = defense.current_ward damage_to_life = final_damage - defense.current_ward defense.current_ward = 0.0 defense.current_life = max(0.0, defense.current_life - damage_to_life) # 8. Boss Stagger / Poise Evaluation (PoE2 Spirit) stagger_triggered = False stagger_applied = 0.0 if boss_stagger and not boss_stagger.is_staggered: stagger_applied = packet.stagger_impact if stagger_applied <= 0.0 and DamageChannel.PHYSICAL in mitigated_channels: stagger_applied = mitigated_channels[DamageChannel.PHYSICAL] * 0.10 boss_stagger.current_stagger += stagger_applied if boss_stagger.current_stagger >= boss_stagger.max_stagger_poise: boss_stagger.is_staggered = True boss_stagger.stagger_duration_remaining_sec = 4.0 stagger_triggered = True return ( CombatHitResult( is_hit=True, is_evaded=False, is_blocked=False, is_critical=is_crit, raw_damage_total=packet.damage_vector.total_raw() * global_multiplier, mitigated_damage_by_channel=mitigated_channels, absorbed_by_ward=round(absorbed_ward, 2), damage_to_life=round(damage_to_life, 2), final_total_damage=round(final_damage, 2), defender_life_remaining=round(defense.current_life, 2), defender_ward_remaining=round(defense.current_ward, 2), stagger_inflicted=round(stagger_applied, 2), boss_staggered_triggered=stagger_triggered, ), next_entropy, )