//
//  MonthDetailView.swift
//  Feels (iOS)
//
//  Created by Trey Tartt on 2/18/22.
//

import SwiftUI

struct MonthDetailView: View {
    @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
    @AppStorage(UserDefaultsStore.Keys.deleteEnable.rawValue, store: GroupUserDefaults.groupDefaults) private var deleteEnabled = true
    @AppStorage(UserDefaultsStore.Keys.moodTint.rawValue, store: GroupUserDefaults.groupDefaults) private var moodTint: MoodTints = .Default

    @State private var showingSheet = false
    @State private var selectedEntry: MoodEntry?
    @State private var showingUpdateEntryAlert = false
    @State private var showUpdateEntryAlert = false
    
    let monthInt: Int
    let yearInt: Int
    @State var entries: [MoodEntry]
    var parentViewModel: HomeViewViewModel
    
    let columns = [
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50)),
        GridItem(.flexible(minimum: 5, maximum: 50))
    ]
    
    var body: some View {
        VStack {
            Text("\(Random.monthName(fromMonthInt: monthInt)) \(String(yearInt))")
                .font(.title)
                .foregroundColor(theme.currentTheme.labelColor)
                .frame(maxWidth: .infinity, alignment: .leading)
                .padding()
                .background(
                    theme.currentTheme.secondaryBGColor
                )
            
            createListView()
                .padding([.leading, .trailing])
            
            monthDetails
                .frame(maxWidth: .infinity, alignment: .leading)
                .background(
                    theme.currentTheme.secondaryBGColor
                )
        }
        .alert(HomeViewViewModel.updateTitleHeader(forEntry: selectedEntry),
               isPresented: $showUpdateEntryAlert) {
            ForEach(Mood.allValues) { mood in
                Button(mood.strValue, action: {
                    if let selectedEntry = selectedEntry {
                        PersistenceController.shared.update(entryDate: selectedEntry.forDate!, withModd: mood)
                    }
                    updateEntries()
                    showUpdateEntryAlert = false
                    selectedEntry = nil
                })
            }
            
            if let selectedEntry = selectedEntry,
               deleteEnabled,
               selectedEntry.mood != .missing {
                Button(String(localized: "content_view_delete_entry"), action: {
                    PersistenceController.shared.update(entryDate: selectedEntry.forDate!, withModd: .missing)
                    updateEntries()
                    showUpdateEntryAlert = false
                })
            }
            
            Button(String(localized: "content_view_fill_in_missing_entry_cancel"), role: .cancel,  action: {
                updateEntries()
                selectedEntry = nil
                showUpdateEntryAlert = false
            })
        }
               .background(
                   theme.currentTheme.bg
               )
    }
    
    private func createListView() -> some View {
        ScrollView {
            LazyVGrid(columns: columns, spacing: 25) {
                ForEach(entries, id: \.self) { entry in
                    listViewEntry(forEntry: entry)
                        .onTapGesture(perform: {
                            if entry.canEdit {
                                selectedEntry = entry
                                showUpdateEntryAlert = true
                            }
                        })
                }
            }
        }
    }
    
    private func listViewEntry(forEntry entry: MoodEntry) -> some View {
        VStack {
            if entry.mood == .placeholder {
                Text(" ")
                    .font(.title3)
                    .foregroundColor(Mood.placeholder.color)
            } else {
                Text(entry.forDate!,
                     format: Date.FormatStyle().day())
                    .font(.title3)
                    .foregroundColor(theme.currentTheme.labelColor)
            }
            
            if entry.mood == .placeholder {
                Circle()
                    .frame(minWidth: 5,
                           maxWidth: 50,
                           minHeight: 5,
                           maxHeight: 50,
                           alignment: .center)
                    .foregroundColor(moodTint.color(forMood: entry.mood))
            } else {
                entry.mood.icon
                    .resizable()
                    .aspectRatio(contentMode: .fit)
                    .frame(minWidth: 5,
                           maxWidth: 50,
                           minHeight: 5,
                           maxHeight: 50,
                           alignment: .center)
                    .foregroundColor(moodTint.color(forMood: entry.mood))
            }
        }
    }
    
    private func updateEntries() {
        parentViewModel.updateData()
        let (startDate, endDate) = Date.dateRange(monthInt: monthInt, yearInt: yearInt)
        let updatedEntries = PersistenceController.shared.getData(startDate: startDate, endDate: endDate, includedDays: [1,2,3,4,5,6,7])
        let padded = MoodEntryFunctions.padMoodEntriesMonth(monthEntries: updatedEntries)
        entries = padded
    }
    
    private var monthDetails: some View {
        VStack {
            SmallRollUpHeaderView(entries: entries,
                                  viewType: .constant(.total))
            
            SmallRollUpHeaderView(entries: entries,
                                  viewType: .constant(.percentageCircle))
                .padding(.top, -20)
        }
        .padding()
    }
}

struct MonthDetailView_Previews: PreviewProvider {
    static var previews: some View {
        MonthDetailView(monthInt: 5, yearInt: 2022, entries:
                            PersistenceController.shared.randomEntries(count: 30).sorted(by: {
            $0.forDate! < $1.forDate!
        }), parentViewModel: HomeViewViewModel(addMonthStartWeekdayPadding: true))
    }
}