Scripts/Item: Change Nitro -> Boosts <- to use the correct knockup effect for their backfire. Also, script that knockup effect to work properly ("usually" deploy a rescue parachute).

(cherry picked from commit 02b1d8bb484ed82be055438cd2bac1db5f18a101)

2 files changed, 54 insertions, 1 deletions

diff --git a/sql/updates/world/master/2020_08_19_01_world_2017_07_18_03_world.sql b/sql/updates/world/master/2020_08_19_01_world_2017_07_18_03_world.sql
new file mode 100644
index 00000000000..17bcc875f61
--- /dev/null
+++ b/sql/updates/world/master/2020_08_19_01_world_2017_07_18_03_world.sql
@@ -0,0 +1,3 @@
+--
+DELETE FROM `spell_script_names` WHERE `scriptname`='spell_item_nitro_boosts_backfire';
+INSERT INTO `spell_script_names` (`spell_id`,`scriptname`) VALUES (54621,'spell_item_nitro_boosts_backfire');
diff --git a/src/server/scripts/Spells/spell_item.cpp b/src/server/scripts/Spells/spell_item.cpp
index 8b05eec1082..df34e4f5af2 100644
--- a/src/server/scripts/Spells/spell_item.cpp
+++ b/src/server/scripts/Spells/spell_item.cpp
@@ -3306,7 +3306,8 @@ class spell_item_brewfest_mount_transformation : public SpellScriptLoader
 enum NitroBoosts
 {
     SPELL_NITRO_BOOSTS_SUCCESS       = 54861,
-    SPELL_NITRO_BOOSTS_BACKFIRE      = 46014,
+    SPELL_NITRO_BOOSTS_BACKFIRE      = 54621,
+    SPELL_NITRO_BOOSTS_PARACHUTE     = 54649,
 };
 
 class spell_item_nitro_boosts : public SpellScriptLoader
@@ -3352,6 +3353,54 @@ class spell_item_nitro_boosts : public SpellScriptLoader
         }
 };
 
+class spell_item_nitro_boosts_backfire : public SpellScriptLoader
+{
+    public:
+        spell_item_nitro_boosts_backfire() : SpellScriptLoader("spell_item_nitro_boosts_backfire") { }
+
+        class spell_item_nitro_boosts_backfire_AuraScript : public AuraScript
+        {
+            PrepareAuraScript(spell_item_nitro_boosts_backfire_AuraScript);
+
+            bool Validate(SpellInfo const* /*spell*/) override
+            {
+                return ValidateSpellInfo({ SPELL_NITRO_BOOSTS_PARACHUTE });
+            }
+
+            void HandleApply(AuraEffect const* /*effect*/, AuraEffectHandleModes /*mode*/)
+            {
+                lastZ = GetTarget()->GetPositionZ();
+            }
+
+            void HandlePeriodicDummy(AuraEffect const* effect)
+            {
+                PreventDefaultAction();
+                float curZ = GetTarget()->GetPositionZ();
+                if (curZ < lastZ)
+                {
+                    if (roll_chance_i(80)) // we don't have enough sniffs to verify this, guesstimate
+                        GetTarget()->CastSpell(GetTarget(), SPELL_NITRO_BOOSTS_PARACHUTE, true, nullptr, effect);
+                    GetAura()->Remove();
+                }
+                else
+                    lastZ = curZ;
+            }
+
+            void Register() override
+            {
+                OnEffectApply += AuraEffectApplyFn(spell_item_nitro_boosts_backfire_AuraScript::HandleApply, EFFECT_1, SPELL_AURA_PERIODIC_TRIGGER_SPELL, AURA_EFFECT_HANDLE_REAL);
+                OnEffectPeriodic += AuraEffectPeriodicFn(spell_item_nitro_boosts_backfire_AuraScript::HandlePeriodicDummy, EFFECT_1, SPELL_AURA_PERIODIC_TRIGGER_SPELL);
+            }
+
+            float lastZ = INVALID_HEIGHT;
+        };
+
+        AuraScript* GetAuraScript() const override
+        {
+            return new spell_item_nitro_boosts_backfire_AuraScript();
+        }
+};
+
 enum TeachLanguage
 {
     SPELL_LEARN_GNOMISH_BINARY      = 50242,
@@ -4928,6 +4977,7 @@ void AddSC_item_spell_scripts()
     new spell_item_impale_leviroth();
     new spell_item_brewfest_mount_transformation();
     new spell_item_nitro_boosts();
+    new spell_item_nitro_boosts_backfire();
     RegisterSpellScript(spell_item_teach_language);
     new spell_item_rocket_boots();
     new spell_item_pygmy_oil();