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[Pokeclicker] Perky Pokerus Pandemic

This script makes it so that Pokérus will spread from any Pokémon (egg) that has it to all of the others inside of the Hatchery, instead of just your starter needing to be in the Hatchery for this to be done.

// ==UserScript==
// @name        [Pokeclicker] Perky Pokerus Pandemic
// @namespace   Pokeclicker Scripts
// @match       https://www.pokeclicker.com/
// @grant       none
// @version     1.0
// @author      Ephenia
// @description This script makes it so that Pokérus will spread from any Pokémon (egg) that has it to all of the others inside of the Hatchery, instead of just your starter needing to be in the Hatchery for this to be done.
// ==/UserScript==

function initPokerusPandemic() {
    App.game.breeding.progressEggs = function(amount) {
        amount *= this.getStepMultiplier();

        amount = Math.round(amount);
        let index =  this.eggList.length;
        while (index-- > 0) {
            const helper = this.hatcheryHelpers.hired()[index];
            if (helper) {
                continue;
            }
            const egg = this.eggList[index]();
            const partyPokemon = App.game.party.caughtPokemon.find(p => p.name == egg.pokemon);
            if (!egg.isNone() && partyPokemon && partyPokemon.canCatchPokerus() && !partyPokemon.pokerus) {
                partyPokemon.pokerus = calculatePokerus();
                function calculatePokerus() {
                    return App.game.breeding.eggList.some(e => {
                        const eggPkrs = App.game.party.caughtPokemon.find(p => p.name == e().pokemon).pokerus;
                        if (!e().canHatch() && !e().isNone() && eggPkrs) {
                            const pokemon = App.game.party.getPokemon(PokemonHelper.getPokemonByName(e().pokemon).id);
                            return pokemon.pokerus;
                        }
                    });
                }
            }
            egg.addSteps(amount, this.multiplier);
            if (this.queueList().length && egg.progress() >= 100) {
                this.hatchPokemonEgg(index);
            }
        }
        this.hatcheryHelpers.addSteps(amount, this.multiplier);
    }
}

function loadScript(){
    const oldInit = Preload.hideSplashScreen;

    Preload.hideSplashScreen = function(){
        const result = oldInit.apply(this, arguments);
        initPokerusPandemic();
        return result;
    }
}

const scriptName = 'perkypokeruspandemic'

if (document.getElementById('scriptHandler') != undefined){
    const scriptElement = document.createElement('div');
    scriptElement.id = scriptName;
    document.getElementById('scriptHandler').appendChild(scriptElement);
    if (localStorage.getItem(scriptName) != null){
        if (localStorage.getItem(scriptName) == 'true'){
            loadScript();
        }
    }
    else{
        localStorage.setItem(scriptName, 'true')
        loadScript();
    }
}
else{
    loadScript();
}