Fix Form Changes with Secondary Fusion Component

Allows form changes when you have a Pokemon chosen as the second component of a fusion. i.e. Charizard/Snorlax can still be Dynamaxed with a Max Mushroom.

This also allows these items to spawn where they wouldn't previously.

src/battle-scene.ts

@@ -2134,8 +2134,14 @@ export default class BattleScene extends SceneBase {
 	}
 
 	triggerPokemonFormChange(pokemon: Pokemon, formChangeTriggerType: { new(...args: any[]): SpeciesFormChangeTrigger }, delayed: boolean = false, modal: boolean = false): boolean {
-		if (pokemonFormChanges.hasOwnProperty(pokemon.species.speciesId)) {
-			const matchingFormChange = pokemonFormChanges[pokemon.species.speciesId].find(fc => fc.findTrigger(formChangeTriggerType) && fc.canChange(pokemon));
+		const speciesIds = [pokemon.species.speciesId];		
+		if (pokemon.isFusion())
+			speciesIds.push(pokemon.fusionSpecies.speciesId)
+
+		speciesIds.forEach(speciesId => 
+		{
+			if (pokemonFormChanges.hasOwnProperty(speciesId)) {					
+				const matchingFormChange = pokemonFormChanges[speciesId].find(fc => fc.findTrigger(formChangeTriggerType) && fc.canChange(pokemon));				
 				if (matchingFormChange) {
 					let phase: Phase;
 					if (pokemon instanceof PlayerPokemon && !matchingFormChange.quiet)
@@ -2151,6 +2157,7 @@ export default class BattleScene extends SceneBase {
 					return true;
 				}
 			}
+		});
 
 		return false;
 	}

src/data/pokemon-forms.ts

@@ -7,6 +7,7 @@ import { Species } from "./enums/species";
 import { StatusEffect } from "./status-effect";
 import { MoveCategory, allMoves } from "./move";
 import { Abilities } from "./enums/abilities";
+import { PokemonSpecies } from "pokenode-ts";
 
 export enum FormChangeItem {
   NONE,
@@ -106,28 +107,42 @@ export class SpeciesFormChange {
   }
 
   canChange(pokemon: Pokemon): boolean {    
-    if (pokemon.species.speciesId !== this.speciesId)
-      return false;
+    const speciesArray = [pokemon.species];
+    const formIndexes = [pokemon.formIndex];
 
-    if (!pokemon.species.forms.length)
-      return false;
+		if (pokemon.isFusion()) {
+			speciesArray.push(pokemon.fusionSpecies);
+      formIndexes.push(pokemon.fusionFormIndex);
+    }   
 
-    const formKeys = pokemon.species.forms.map(f => f.formKey);
-    if (formKeys[pokemon.formIndex] !== this.preFormKey)
-      return false;
+    const formMatch = [true, true];
+    for (let i = 0; i < speciesArray.length; ++i) {
+      const species = speciesArray[i];
+      const formIndex = formIndexes[i];
       
-    if (formKeys[pokemon.formIndex] === this.formKey)
-      return false;
+      if (species.speciesId !== this.speciesId)
+        formMatch[i] = false;
+  
+      if (!species.forms.length)
+        formMatch[i] = false;
+  
+      const formKeys = species.forms.map(f => f.formKey);
+      if (formKeys[formIndex] !== this.preFormKey)
+        formMatch[i] = false;
+  
+      if (formKeys[formIndex] === this.formKey)
+        formMatch[i] = false;
   
       for (let condition of this.conditions) {
         if (!condition.predicate(pokemon))
-        return false;
+          formMatch[i] = false;
       }
   
       if (!this.trigger.canChange(pokemon))
-      return false;
+        formMatch[i] = false;
+    }
 
-    return true;
+    return formMatch.some(x => x);
   }
 
   findTrigger(triggerType: { new(...args: any[]): SpeciesFormChangeTrigger }): SpeciesFormChangeTrigger {
@@ -304,7 +319,7 @@ export function getSpeciesFormChangeMessage(pokemon: Pokemon, formChange: Specie
   const isMega = formChange.formKey.indexOf(SpeciesFormKey.MEGA) > -1;
   const isGmax = formChange.formKey.indexOf(SpeciesFormKey.GIGANTAMAX) > -1;
   const isEmax = formChange.formKey.indexOf('eternamax') > -1;
-  const isRevert = !isMega && formChange.formKey === pokemon.species.forms[0].formKey;
+  const isRevert = !isMega && ((!!pokemon.species.forms.length && formChange.formKey === pokemon.species.forms[0].formKey) || (pokemon.isFusion() && pokemon.fusionSpecies.forms[0].formKey));
   const prefix = !pokemon.isPlayer() ? pokemon.hasTrainer() ? 'Foe ' : 'Wild ' : 'Your ';
   if (isMega)
     return `${prefix}${preName} mega-evolved\ninto ${pokemon.name}!`;

src/field/pokemon.ts

@@ -2507,8 +2507,15 @@ export class PlayerPokemon extends Pokemon {
   }
 
   changeForm(formChange: SpeciesFormChange): Promise<void> {
+    const matchesBase = this.species.speciesId == formChange.speciesId;
+    
     return new Promise(resolve => {
-      this.formIndex = Math.max(this.species.forms.findIndex(f => f.formKey === formChange.formKey), 0);
+      const newFormIndex = Math.max((matchesBase ? this.species : this.fusionSpecies).forms.findIndex(f => f.formKey === formChange.formKey), 0);
+      if (matchesBase)
+        this.formIndex = newFormIndex;
+      else
+        this.fusionFormIndex = newFormIndex;
+
       this.generateName();
       const abilityCount = this.getSpeciesForm().getAbilityCount();
       if (this.abilityIndex >= abilityCount) // Shouldn't happen

src/modifier/modifier-type.ts

@@ -574,6 +574,10 @@ export class FormChangeItemModifierType extends PokemonModifierType implements G
         && (fc.trigger as SpeciesFormChangeItemTrigger).item === this.formChangeItem))
         return null;
 
+      if (pokemon.isFusion() && pokemonFormChanges.hasOwnProperty(pokemon.fusionSpecies.speciesId) && !!pokemonFormChanges[pokemon.fusionSpecies.speciesId].find(fc => fc.trigger.hasTriggerType(SpeciesFormChangeItemTrigger)
+        && (fc.trigger as SpeciesFormChangeItemTrigger).item === this.formChangeItem))
+        return null;
+
       return PartyUiHandler.NoEffectMessage;
     }, FormChangeItem[formChangeItem].toLowerCase());
 
@@ -686,7 +690,10 @@ class FormChangeItemModifierTypeGenerator extends ModifierTypeGenerator {
         return new FormChangeItemModifierType(pregenArgs[0] as FormChangeItem);
 
       const formChangeItemPool = party.filter(p => pokemonFormChanges.hasOwnProperty(p.species.speciesId)).map(p => {
-        const formChanges = pokemonFormChanges[p.species.speciesId];
+        let formChanges = pokemonFormChanges[p.species.speciesId];
+        if(p.isFusion())
+          formChanges = formChanges.concat(pokemonFormChanges[p.fusionSpecies.speciesId]);
+
         return formChanges.filter(fc => ((fc.formKey.indexOf(SpeciesFormKey.MEGA) === -1 && fc.formKey.indexOf(SpeciesFormKey.PRIMAL) === -1) || party[0].scene.getModifiers(Modifiers.MegaEvolutionAccessModifier).length)
           && ((fc.formKey.indexOf(SpeciesFormKey.GIGANTAMAX) === -1 && fc.formKey.indexOf(SpeciesFormKey.ETERNAMAX) === -1) || party[0].scene.getModifiers(Modifiers.GigantamaxAccessModifier).length))
           .map(fc => fc.findTrigger(SpeciesFormChangeItemTrigger) as SpeciesFormChangeItemTrigger)