import clr

clr.AddReference("System")

clr.AddReference("Kingdee.BOS")

clr.AddReference("Kingdee.BOS.Core")

clr.AddReference("Kingdee.BOS.DataEntity")

clr.AddReference("Kingdee.BOS.App")

clr.AddReference("Kingdee.BOS.Contracts")

clr.AddReference("Kingdee.BOS.ServiceHelper")

from Kingdee.BOS.App import *  

from Kingdee.BOS import *

from Kingdee.BOS.Contracts import *

from Kingdee.BOS.Contracts.Report import *

from Kingdee.BOS.Core import *

from Kingdee.BOS.Core.Metadata import *

from Kingdee.BOS.Core.Report import *

from Kingdee.BOS.Core.SqlBuilder import *

from Kingdee.BOS.Core.Enums import * 

from Kingdee.BOS.App.Data import *

from Kingdee.BOS.Orm.DataEntity import *

from System import *

from System.ComponentModel import *

from System.Collections.Generic import *

from System.Text import *

from System.Threading.Tasks import *

from Kingdee.BOS.ServiceHelper import *

def show_warning(message):

    this.View.ShowErrMessage(message)

def is_date_range_overlapping(start1, end1, start2, end2):  

    return not (end2 <= start2 or end2 <= start1)

def check_overlapping_periods(data_object, entry_property_name):  

    entries = getattr(data_object, entry_property_name, None)   

    if entries is None or not entries:  

        return False  

    for i in range(len(entries)):  

        entry1 = entries[i]  

        for j in range(i + 1, len(entries)):  

            entry2 = entries[j]  

            if entry1.FMaterialId == entry2.FMaterialId:  

                if is_date_range_overlapping(  

                    entry1.FEntryEffectiveDate, entry1.FEntryExpiryDate,

                    entry2.FEntryEffectiveDate, entry2.FEntryExpiryDate  

                ):  

                    return True  

    return False 

def BeforeDoOperation(e):

    opCode = e.Operation.FormOperation.Operation.ToUpperInvariant()

    if opCode == "SAVE":

        data_object = this.View.Model.DataObject

        if check_overlapping_periods(data_object, "FPriceListEntries"):

            e.Cancel = True