//
//  PushSubscriptionView.swift
//  Tusker
//
//  Created by Shadowfacts on 4/7/24.
//  Copyright © 2024 Shadowfacts. All rights reserved.
//

import SwiftUI
import UserAccounts
import PushNotifications
import TuskerComponents

struct PushSubscriptionView: View {
    let account: UserAccountInfo
    let subscription: PushSubscription?
    let updateSubscription: (PushSubscription.Alerts, PushSubscription.Policy) async -> Bool

    var body: some View {
        if let subscription {
            PushSubscriptionSettingsView(account: account, subscription: subscription, updateSubscription: updateSubscription)
        } else {
            Text("No notifications")
                .foregroundStyle(.secondary)
        }
    }
}

private struct PushSubscriptionSettingsView: View {
    let account: UserAccountInfo
    let subscription: PushSubscription
    let updateSubscription: (PushSubscription.Alerts, PushSubscription.Policy) async -> Bool
    @State private var isLoading: [PushSubscription.Alerts: Bool] = [:]
    
    init(account: UserAccountInfo, subscription: PushSubscription, updateSubscription: @escaping (PushSubscription.Alerts, PushSubscription.Policy) async -> Bool) {
        self.account = account
        self.subscription = subscription
        self.updateSubscription = updateSubscription
    }
    
    var body: some View {
        VStack(alignment: .prefsAvatar) {
            toggle("All", alert: [.mention, .favorite, .reblog, .follow, .followRequest, .poll, .update])
            toggle("Mentions", alert: .mention)
            toggle("Favorites", alert: .favorite)
            toggle("Reblogs", alert: .reblog)
            toggle("Follows", alert: [.follow, .followRequest])
            toggle("Polls", alert: .poll)
            toggle("Edits", alert: .update)
            // status notifications not supported until we can enable/disable them in the app
        }
        // this is the default value of the alignment guide, but this modifier is loading bearing
        .alignmentGuide(.prefsAvatar, computeValue: { dimension in
            dimension[.leading]
        })
        // otherwise the flexible view makes the containing stack extend under the edge of the list row
        .padding(.leading, 38)
    }
    
    private func toggle(_ titleKey: LocalizedStringKey, alert: PushSubscription.Alerts) -> some View {
        let binding: Binding<AsyncToggle.Mode> = Binding {
            isLoading[alert] == true ? .loading : subscription.alerts.contains(alert) ? .on : .off
        } set: { newValue in
            isLoading[alert] = newValue == .loading
        }
        return AsyncToggle(titleKey, mode: binding) {
            return await updateSubscription(alert: alert, isOn: $0)
        }
    }
    
    private func updateSubscription(alert: PushSubscription.Alerts, isOn: Bool) async -> Bool {
        var newAlerts = subscription.alerts
        if isOn {
            newAlerts.insert(alert)
        } else {
            newAlerts.remove(alert)
        }
        return await updateSubscription(newAlerts, subscription.policy)
    }
}

//#Preview {
//    PushSubscriptionView()
//}