split all the logic out of filter view into protocols and other shit

Shared/Models/FilterViewModel.swift

@@ -0,0 +1,35 @@
+//
+//  FilterViewModel.swift
+//  Feels
+//
+//  Created by Trey Tartt on 1/17/22.
+//
+
+import Foundation
+
+class FilterViewModel: ObservableObject {    
+    @Published public var entryStartDate: Date = Date()
+    @Published public var entryEndDate: Date = Date()
+    @Published var selectedDays = [Int]()
+    
+    // year, month, items
+    @Published public private(set) var data = [Int: [Int: [DayChartView]]]()
+    @Published public private(set) var numberOfRatings: Int = 0
+    public private(set) var uncategorizedData = [MoodEntry]() {
+        didSet {
+            self.numberOfRatings = uncategorizedData.count
+        }
+    }
+    
+    private let chartViewBuilder = DayChartViewChartBuilder()
+    
+    public func filterEntries(startDate: Date, endDate: Date) {
+        let filteredEntries = PersistenceController.shared.getData(startDate: startDate,
+                                                                   endDate: endDate,
+                                                                   includedDays: selectedDays)
+        data.removeAll()
+        let filledOutData = chartViewBuilder.buildGridData(withData: filteredEntries)
+        data = filledOutData
+        uncategorizedData = filteredEntries
+    }
+}