fix issue with two votes on the same date

fix issue with header not showing correct vote date
split logic for Persistence into different files
create class that deals with voting time, existing votes, and what should be shown based on that

Shared/Persisence/PersistenceGET.swift

@@ -0,0 +1,92 @@
+//
+//  PersistenceGET.swift
+//  Feels
+//
+//  Created by Trey Tartt on 2/17/22.
+//
+
+import CoreData
+
+extension PersistenceController {
+    public func getEntry(byDate date: Date) -> MoodEntry? {
+        let startDate = Calendar.current.startOfDay(for: date)
+        let endDate = Calendar.current.date(byAdding: .day, value: 1, to: startDate)!
+        
+        let predicate = NSPredicate(format: "forDate >= %@ && forDate <= %@ ",
+                                    startDate as NSDate,
+                                    endDate as NSDate)
+        
+        let fetchRequest = NSFetchRequest<MoodEntry>(entityName: "MoodEntry")
+        fetchRequest.predicate = predicate
+        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "forDate", ascending: true)]
+        let data = try! viewContext.fetch(fetchRequest)
+        return data.first
+    }
+    
+    public func getData(startDate: Date, endDate: Date, includedDays: [Int]) -> [MoodEntry] {
+        try! viewContext.setQueryGenerationFrom(.current)
+        viewContext.refreshAllObjects()
+        
+        var includedDays16 = [Int16]()
+        
+        if includedDays.isEmpty {
+            includedDays16 = [Int16(1), Int16(2), Int16(3), Int16(4), Int16(5), Int16(6), Int16(7)]
+        } else {
+            includedDays16 = includedDays.map({
+                Int16($0)
+            })
+        }
+        let predicate = NSPredicate(format: "forDate >= %@ && forDate <= %@ && weekDay IN %@",
+                                    startDate as NSDate,
+                                    endDate as NSDate,
+                                    includedDays16)
+        
+        let fetchRequest = NSFetchRequest<MoodEntry>(entityName: "MoodEntry")
+        fetchRequest.predicate = predicate
+        fetchRequest.sortDescriptors = [NSSortDescriptor(key: "forDate", ascending: true)]
+        let data = try! viewContext.fetch(fetchRequest)
+        return data
+    }
+    
+    public func splitIntoYearMonth() ->  [Int: [Int: [MoodEntry]]] {
+        let data = PersistenceController.shared.getData(startDate: Date(timeIntervalSince1970: 0),
+                                                        endDate: Date(),
+                                                        includedDays: [1,2,3,4,5,6,7]).sorted(by: {
+            $0.forDate! < $1.forDate!
+        })
+        var returnData = [Int: [Int: [MoodEntry]]]()
+        
+        if let earliestEntry = data.first,
+           let lastEntry = data.last {
+            
+            let calendar = Calendar.current
+            let components = calendar.dateComponents([.year], from: earliestEntry.forDate!)
+            let earliestYear = components.year!
+            
+            let latestComponents = calendar.dateComponents([.year], from: lastEntry.forDate!)
+            let latestYear = latestComponents.year!
+            
+            for year in earliestYear...latestYear {
+                var allMonths = [Int: [MoodEntry]]()
+                
+                for month in (1...12) {
+                    var components = DateComponents()
+                    components.month = month
+                    components.year = year
+                    let startDateOfMonth = Calendar.current.date(from: components)!
+                    
+                    let items = data.filter({ entry in
+                        let components = calendar.dateComponents([.month, .year], from: startDateOfMonth)
+                        let entryComponents = calendar.dateComponents([.month, .year], from: entry.forDate!)
+                        return (components.month == entryComponents.month && components.year == entryComponents.year)
+                    })
+                    if !items.isEmpty {
+                        allMonths[month] = items
+                    }
+                }
+                returnData[year] = allMonths
+            }
+        }
+        return returnData
+    }
+}