Unit/Spell: Resolve weapon skill usage bugs

cmangos/issues#3525

src/game/Entities/Unit.cpp

@@ -3321,7 +3321,7 @@ float Unit::CalculateEffectiveDodgeChance(const Unit* attacker, WeaponAttackType
     // Own chance appears to be zero / below zero / unmeaningful for some reason (debuffs?): skip calculation, unit is incapable
     if (chance < 0.005f)
         return 0.0f;
-    const bool weapon = (!ability || ability->EquippedItemClass == ITEM_CLASS_WEAPON);
+    const bool weapon = (!ability || IsSpellUseWeaponSkill(ability));
     // Skill difference can be negative (and reduce our chance to mitigate an attack), which means:
     // a) Attacker's level is higher
     // b) Attacker has +skill bonuses
@@ -3352,7 +3352,7 @@ float Unit::CalculateEffectiveParryChance(const Unit* attacker, WeaponAttackType
     // Own chance appears to be zero / below zero / unmeaningful for some reason (debuffs?): skip calculation, unit is incapable
     if (chance < 0.005f)
         return 0.0f;
-    const bool weapon = (!ability || ability->EquippedItemClass == ITEM_CLASS_WEAPON);
+    const bool weapon = (!ability || IsSpellUseWeaponSkill(ability));
     // Skill difference can be negative (and reduce our chance to mitigate an attack), which means:
     // a) Attacker's level is higher
     // b) Attacker has +skill bonuses
@@ -3385,7 +3385,7 @@ float Unit::CalculateEffectiveBlockChance(const Unit* attacker, WeaponAttackType
     // Own chance appears to be zero / below zero / unmeaningful for some reason (debuffs?): skip calculation, unit is incapable
     if (chance < 0.005f)
         return 0.0f;
-    const bool weapon = (!ability || ability->EquippedItemClass == ITEM_CLASS_WEAPON);
+    const bool weapon = (!ability || IsSpellUseWeaponSkill(ability));
     // Skill difference can be negative (and reduce our chance to mitigate an attack), which means:
     // a) Attacker's level is higher
     // b) Attacker has +skill bonuses
@@ -3884,7 +3884,7 @@ float Unit::CalculateEffectiveCritChance(const Unit* victim, WeaponAttackType at
     // Skip victim calculation if positive ability
     if (ability && IsPositiveSpell(ability, this, victim))
         return std::max(0.0f, std::min(chance, 100.0f));
-    const bool weapon = (!ability || ability->EquippedItemClass == ITEM_CLASS_WEAPON);
+    const bool weapon = (!ability || IsSpellUseWeaponSkill(ability));
     // Skill difference can be both negative and positive.
     // a) Positive means that attacker's level is higher or additional weapon +skill bonuses
     // b) Negative means that victim's level is higher or additional +defense bonuses
@@ -3914,7 +3914,7 @@ float Unit::CalculateEffectiveMissChance(const Unit *victim, WeaponAttackType at
     if (chance < 0.005f)
         return 0.0f;
     const bool ranged = (attType == RANGED_ATTACK);
-    const bool weapon = (!ability || ability->EquippedItemClass == ITEM_CLASS_WEAPON);
+    const bool weapon = (!ability || IsSpellUseWeaponSkill(ability));
     // Check if dual wielding, add additional miss penalty - when mainhand has on next swing spell, offhand doesnt suffer penalty
     if (!ability && !ranged && hasOffhandWeaponForAttack() && (!m_currentSpells[CURRENT_MELEE_SPELL] || !IsNextMeleeSwingSpell(m_currentSpells[CURRENT_MELEE_SPELL]->m_spellInfo)))
         chance += 19.0f;

src/game/Spells/SpellMgr.h

@@ -1853,6 +1853,12 @@ inline bool IsIgnoreRootSpell(SpellEntry const* spellInfo)
     return false;
 }
 
+inline bool IsSpellUseWeaponSkill(SpellEntry const* spellInfo)
+{
+    // note: this is not a mirror of client function - that function does not work for Bloodthirst edgecase
+    return spellInfo->EquippedItemClass == ITEM_CLASS_WEAPON || spellInfo->DmgClass == SPELL_DAMAGE_CLASS_MELEE || spellInfo->DmgClass == SPELL_DAMAGE_CLASS_RANGED && spellInfo->HasAttribute(SPELL_ATTR_USES_RANGED_SLOT);
+}
+
 inline uint32 GetDispellMask(DispelType dispel)
 {
     // If dispell all