Conditionally prevent damaging and spell auto-targeting Golem

Source/missiles.cpp

@@ -206,7 +206,7 @@ bool MonsterMHit(const Player &player, int monsterId, int mindam, int maxdam, in
 {
 	auto &monster = Monsters[monsterId];
 
-	if (!monster.isPossibleToHit() || monster.isImmune(t, damageType))
+	if (!monster.isPossibleToHit() || monster.isImmune(t, damageType) || !monster.canBeDamagedByPlayer(player))
 		return false;
 
 	int hit = RandomIntLessThan(100);
@@ -3532,9 +3532,15 @@ void ProcessChainLightning(Missile &missile)
 	int rad = std::min<int>(missile._mispllvl + 3, MaxCrawlRadius);
 	Crawl(1, rad, [&](Displacement displacement) {
 		Point target = position + displacement;
-		if (InDungeonBounds(target) && dMonster[target.x][target.y] > 0) {
-			dir = GetDirection(position, target);
-			AddMissile(position, target, dir, MissileID::LightningControl, TARGET_MONSTERS, id, 1, missile._mispllvl);
+		const auto &monsterId = dMonster[target.x][target.y];
+		if (InDungeonBounds(target) && monsterId > 0) {
+			const auto &player = Players[id];
+			const auto &monster = Monsters[std::abs(monsterId - 1)];
+			// Should we also be checking isPossibleToHit() and isImmune()?
+			if (monster.canBeDamagedByPlayer(player)) {
+				dir = GetDirection(position, target);
+				AddMissile(position, target, dir, MissileID::LightningControl, TARGET_MONSTERS, id, 1, missile._mispllvl);
+			}
 		}
 		return false;
 	});
@@ -4029,13 +4035,19 @@ void ProcessElemental(Missile &missile)
 		if (missile.var3 == 1) {
 			missile.var3 = 2;
 			missile._mirange = 255;
+
+			auto *player = missile.sourcePlayer();
 			auto *nextMonster = FindClosest(missilePosition, 19);
-			if (nextMonster != nullptr) {
+
+			// Should we also be checking isPossibleToHit() and isImmune()?
+			if (nextMonster != nullptr && nextMonster->canBeDamagedByPlayer(*player)) {
 				Direction sd = GetDirection(missilePosition, nextMonster->position.tile);
+
 				SetMissDir(missile, sd);
 				UpdateMissileVelocity(missile, nextMonster->position.tile, 16);
 			} else {
 				Direction sd = Players[missile._misource]._pdir;
+
 				SetMissDir(missile, sd);
 				UpdateMissileVelocity(missile, missilePosition + sd, 16);
 			}
@@ -4074,13 +4086,17 @@ void ProcessBoneSpirit(Missile &missile)
 		if (missile.var3 == 1) {
 			missile.var3 = 2;
 			missile._mirange = 255;
+			auto *player = missile.sourcePlayer();
 			auto *monster = FindClosest(c, 19);
-			if (monster != nullptr) {
+
+			// Should we also be checking isPossibleToHit() and isImmune()?
+			if (monster != nullptr && monster->canBeDamagedByPlayer(*player)) {
 				missile._midam = monster->hitPoints >> 7;
 				SetMissDir(missile, GetDirection(c, monster->position.tile));
 				UpdateMissileVelocity(missile, monster->position.tile, 16);
 			} else {
 				Direction sd = Players[missile._misource]._pdir;
+
 				SetMissDir(missile, sd);
 				UpdateMissileVelocity(missile, c + sd, 16);
 			}

Source/monster.cpp

@@ -4829,6 +4829,12 @@ bool Monster::isPlayerMinion() const
 	return (flags & MFLAG_GOLEM) != 0 && (flags & MFLAG_BERSERK) == 0;
 }
 
+bool Monster::canBeDamagedByPlayer(const Player &player) const
+{
+	return !(player.getId() == getId()
+	    || (isPlayerMinion() && sgGameInitInfo.bFriendlyFire == 0 && player.friendlyMode));
+}
+
 bool Monster::isPossibleToHit() const
 {
 	return !(hitPoints >> 6 <= 0

Source/monster.h

@@ -438,6 +438,14 @@ struct Monster { // note: missing field _mAFNum
 	 */
 	[[nodiscard]] bool isPlayerMinion() const;
 
+	/**
+	 * @brief Can this monster be damaged by the player?
+	 *
+	 * Used for Golems to determine whether or not a player is able to damage it.
+	 * Conditions are set based on Friendly Fire, Player Attack/Friend, and ownership.
+	 */
+	[[nodiscard]] bool canBeDamagedByPlayer(const Player &player) const;
+
 	bool isPossibleToHit() const;
 	void tag(const Player &tagger);
 

Source/player.cpp

@@ -571,7 +571,7 @@ bool PlrHitMonst(Player &player, Monster &monster, bool adjacentDamage = false)
 {
 	int hper = 0;
 
-	if (!monster.isPossibleToHit())
+	if (!monster.isPossibleToHit() || !monster.canBeDamagedByPlayer(player))
 		return false;
 
 	if (adjacentDamage) {
@@ -2096,6 +2096,11 @@ bool Player::isLevelOwnedByLocalClient() const
 	return false;
 }
 
+Monster &Player::golem() const
+{
+	return Monsters[getId()];
+}
+
 Player *PlayerAtPosition(Point position, bool ignoreMovingPlayers /*= false*/)
 {
 	if (!InDungeonBounds(position))

Source/player.h

@@ -894,6 +894,9 @@ struct Player {
 
 	/** @brief Checks if the player level is owned by local client. */
 	bool isLevelOwnedByLocalClient() const;
+
+	/** @brief Returns a reference to the Golem owned by the player. */
+	Monster &golem() const;
 };
 
 extern DVL_API_FOR_TEST uint8_t MyPlayerId;

Source/spells.cpp

@@ -147,6 +147,12 @@ int GetManaAmount(const Player &player, SpellID sn)
 
 void ConsumeSpell(Player &player, SpellID sn)
 {
+	if (sn == SpellID::Golem && &player == MyPlayer) {
+		Monster &golem = player.golem();
+
+		if (golem.hitPoints <= 0)
+			return;
+	}
 	switch (player.executedSpell.spellType) {
 	case SpellType::Skill:
 	case SpellType::Invalid: