mu3-mods/Unlockers/UnlockGameEvents/MU3.Client/patch_PacketGetGameEvent.cs

using MU3.Data;
using MU3.Operation;
using MU3.Util;
using System;
using System.Linq;

namespace MU3.Client;

class patch_PacketGetGameEvent: Packet {
    private Operation.GameEvent _gameEvent;

    public extern State orig_proc();
    public override State proc() {
        State state = orig_proc();
        if(state == State.Done) {
            DateTime endDate = DateTime.Parse("2099-01-01 05:00:00.0");
            _gameEvent ??= new Operation.GameEvent();

            bool skipMissions = checkMissionEvents();

            foreach(EventData eventData in SingletonStateMachine<DataManager, DataManager.EState>.instance.allEventData) {
                IdPeriod idPeriod = Enumerable.FirstOrDefault(_gameEvent.list, (IdPeriod e) => e.id == eventData.id);
                if(skipMissions && eventData.itemType == DataStudio.EventType.MissionEvent) {
                    continue;
                }
                if(idPeriod != null) {
                    if(idPeriod.period.endDate < CustomDateTime.Now) {
                        idPeriod.period.endDate = endDate;
                    }
                } else {
                    idPeriod = new() {
                        id = eventData.id,
                        period = new Period(DateTime.MinValue.Date, endDate)
                    };
                    _gameEvent.list.Add(idPeriod);
                    _gameEvent.lastUpdate = CustomDateTime.Now;
                }
            }
        }
        return state;
    }

    // Check whether there is only one active mission event
    private bool checkMissionEvents() {
        bool found = false;
        foreach(EventData eventData in SingletonStateMachine<DataManager, DataManager.EState>.instance.allEventData) {
            if(eventData.itemType == DataStudio.EventType.MissionEvent) {
                IdPeriod idPeriod = Enumerable.FirstOrDefault(_gameEvent.list, (IdPeriod e) => e.id == eventData.id);
                if(idPeriod?.period.startDate < CustomDateTime.Now && idPeriod?.period.endDate > CustomDateTime.Now) {
                    if(!found) {
                        found = true;
                    } else {
                        return false;
                    }
                }
            }
        }
        return found;
    }
}