//
//  SettingsView.swift
//  Feels
//
//  Created by Trey Tartt on 1/8/22.
//

import SwiftUI
import CloudKitSyncMonitor

struct SettingsView: View {
    @Environment(\.dismiss) var dismiss
    
    let editedDataClosure: (() -> Void)
    let updateBoardingDataClosure: ((OnboardingData) -> Void)
    
    @State private var showOnboarding = false
    
    @State private var showSpecialThanks = false
    @State private var showWhyBGMode = false
    @ObservedObject var syncMonitor = SyncMonitor.shared
    
    @AppStorage(UserDefaultsStore.Keys.useCloudKit.rawValue, store: GroupUserDefaults.groupDefaults) private var useCloudKit = false
    @AppStorage(UserDefaultsStore.Keys.deleteEnable.rawValue, store: GroupUserDefaults.groupDefaults) private var deleteEnabled = true
    @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
    
    var body: some View {
        ZStack {
            Color(theme.secondaryBGColor)
            ScrollView {
                VStack {
                    Group {
                        closeButtonView
                            .padding()
                        
                        cloudKitEnable
                        canDelete
                        changeIcon
                        themePicker
                        showOnboardingButton
                        whyBackgroundMode
                        specialThanksCell
                    }
                    
                    Group {
                        addTestDataCell
                        clearDB
                        
                        if useCloudKit {
                            cloudKitStatus
                        }
                    }
                    Spacer()
                }
            }
            .padding()
            
        }.sheet(isPresented: $showOnboarding) {
            OnboardingMain(onboardingData: UserDefaultsStore.getOnboarding(),
                           updateBoardingDataClosure: { onboardingData in
                updateBoardingDataClosure(onboardingData)
                showOnboarding = false
            })
        }
        .ignoresSafeArea()
    }
    
    private var closeButtonView: some View {
        HStack{
            Spacer()
            Button(action: {
                dismiss()
            }, label: {
                Text(String(localized: "settings_view_exit"))
                    .font(.body)
                    .foregroundColor(Color(UIColor.systemBlue))
            })
        }
    }
    
    private var specialThanksCell: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Button(action: {
                    withAnimation{
                        showSpecialThanks.toggle()
                    }
                }, label: {
                    Text(String(localized: "settings_view_special_thanks_to_title"))
                })
                    .padding()
                
                if showSpecialThanks {
                    Text(String(localized: "settings_view_special_thanks_to_body"))
                        .padding()
                }
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var addTestDataCell: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Button(action: {
                PersistenceController.shared.populateTestData()
                editedDataClosure()
            }, label: {
                Text("Add test data")
            })
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var clearDB: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Button(action: {
                PersistenceController.shared.clearDB()
                editedDataClosure()
            }, label: {
                Text("Clear DB")
            })
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var whyBackgroundMode: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Button(action: {
                    withAnimation{
                        showWhyBGMode.toggle()
                    }
                }, label: {
                    Text(String(localized: "settings_view_why_bg_mode_title"))
                })
                    .padding()
                if showWhyBGMode {
                    Text(String(localized: "settings_view_why_bg_mode_body"))
                        .padding()
                }
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    let iconSets: [(String,String)] = [
        ("PurpleFeelsAppIcon", "PurpleAppIcon"),
        ("RedFeelsAppIcon", "RedAppIcon")
    ]
    
    private var changeIcon: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Text(String(localized: "settings_view_change_icon"))
                HStack {
                    
                    Button(action: {
                        UIApplication.shared.setAlternateIconName(nil)
                    }, label: {
                        Image("FeelsAppIcon", bundle: .main)
                            .resizable()
                            .frame(width: 50, height:50)
                            .cornerRadius(10)
                    })
                        .padding()
                    
                    ForEach(iconSets, id: \.self.0){ iconSet in
                        Button(action: {
                            UIApplication.shared.setAlternateIconName(iconSet.1) { (error) in
                                // FIXME: Handle error
                            }
                        }, label: {
                            Image(iconSet.0, bundle: .main)
                                .resizable()
                                .frame(width: 50, height:50)
                                .cornerRadius(10)
                        })
                            .padding()
                    }
                }
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var showOnboardingButton: some View {
        ZStack {
            Color(UIColor.systemBackground)
            Button(action: {
                showOnboarding.toggle()
            }, label: {
                Text(String(localized: "settings_view_show_onboarding"))
            })
                .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var cloudKitEnable: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Toggle(String(localized: "settings_use_cloudkit_title"),
                       isOn: $useCloudKit)
                    .onChange(of: useCloudKit) { value in
                        PersistenceController.shared.switchContainer()
                    }
                    .padding()
                Text(String(localized: "settings_use_cloudkit_body"))
            }
            .padding(.bottom)
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var cloudKitStatus: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Image(systemName: syncMonitor.syncStateSummary.symbolName)
                    .foregroundColor(syncMonitor.syncStateSummary.symbolColor)
                Text( syncMonitor.syncStateSummary.isBroken ? "cloudkit is broken" : "cloudkit is good")
            }
            .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var canDelete: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Toggle(String(localized: "settings_use_delete_enable"),
                       isOn: $deleteEnabled)
                    .padding()
            }
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
    
    private var themePicker: some View {
        ZStack {
            Color(UIColor.systemBackground)
            VStack {
                Text(String(localized: "settings_background_title"))
                HStack {
                    Spacer()
                    ForEach(Theme.allCases, id:\.rawValue) { aTheme in
                        Button(action: {
                            theme = aTheme
                        }, label: {
                            VStack {
                                aTheme.preview
                                Text(aTheme.title)
                            }
                        })
                        Spacer()
                    }
                }
                .padding(.top)
            }
            .padding()
        }
        .fixedSize(horizontal: false, vertical: true)
        .cornerRadius(10, corners: [.topLeft, .topRight, .bottomLeft, .bottomRight])
    }
}

struct SettingsView_Previews: PreviewProvider {
    static var previews: some View {
        SettingsView(editedDataClosure: {
            
        }, updateBoardingDataClosure: { _ in
            
        })
        
        SettingsView(editedDataClosure: {
            
        }, updateBoardingDataClosure: { _ in
            
        })
            .preferredColorScheme(.dark)
    }
}