//
//  PurchaseButtonView.swift
//  Feels
//
//  Created by Trey Tartt on 7/7/22.
//

import SwiftUI
import StoreKit

struct PurchaseButtonView: View {
    @AppStorage(UserDefaultsStore.Keys.theme.rawValue, store: GroupUserDefaults.groupDefaults) private var theme: Theme = .system
    @AppStorage(UserDefaultsStore.Keys.textColor.rawValue, store: GroupUserDefaults.groupDefaults) private var textColor: Color = DefaultTextColor.textColor
    @AppStorage(UserDefaultsStore.Keys.firstLaunchDate.rawValue, store: GroupUserDefaults.groupDefaults) private var firstLaunchDate = Date()
    
    var iapManager: IAPManager
    
    private let showCountdownTimer: Bool
    private let showManageSubClosure: (() -> Void)?
 
    public init(iapManager: IAPManager, showManageSubClosure: (() -> Void)? = nil, showCountdownTimer: Bool = false) {
        self.showManageSubClosure = showManageSubClosure
        self.iapManager = iapManager
        self.showCountdownTimer = showCountdownTimer
    }
    
    var body: some View {
        ZStack {
            // if we should show the iap warning that means no purchase which means
            // we should show buy options
            switch iapManager.showIAPWarning {
            case true:
                VStack {
                    buyOptionsView
                        .background(theme.currentTheme.secondaryBGColor)
                }
            case false:
                subscribedView
                    .background(theme.currentTheme.secondaryBGColor)
            }
        }
    }
    
    private var buyOptionsSetingsView: some View {
        GeometryReader { metrics in
            VStack(spacing: 20) {
                Text(String(localized: "purchase_view_title"))
                    .foregroundColor(textColor)
                    .frame(minWidth: 0, maxWidth: .infinity, alignment: .leading)
                    .padding([.leading, .trailing])
                VStack(alignment: .leading) {
                    ForEach(iapManager.sortedSubscriptionKeysByPriceOptions, id: \.self) { product in
                        HStack {
                            Button(action: {
                                purchase(product: product)
                            }, label: {
                                Text("\(product.displayPrice)\n\(product.displayName)")
                                    .foregroundColor(.white)
                                    .bold()
                                    .frame(maxWidth: .infinity)
                                    .contentShape(Rectangle())
                            })
                            .frame(maxWidth: .infinity)
                            .frame(height: 50)
                            .padding()
                            .background(RoundedRectangle(cornerRadius: 10).fill(iapManager.colorForIAPButton(iapIdentifier: product.id)))
                        }
                    }
                }
                .padding([.leading, .leading])
            }
        }
    }
    
    private var buyOptionsView: some View {
        VStack {
            ZStack {
                theme.currentTheme.secondaryBGColor
                
                if iapManager.isLoadingSubscriptions {
                    VStack(spacing: 20) {
                        Text(String(localized: "purchase_view_loading"))
                            .font(.body)
                            .bold()
                            .frame(minWidth: 0, maxWidth: .infinity, alignment: .center)
                        ProgressView()
                    }
                } else {
                    
                    VStack(spacing: 20) {
                        Text(String(localized: "purchase_view_title"))
                            .font(.body)
                            .bold()
                            .foregroundColor(textColor)
                            .frame(minWidth: 0, maxWidth: .infinity, alignment: .leading)
                            .padding(.top)
                        
                        if showCountdownTimer {
                            if let date = Calendar.current.date(byAdding: .day, value: 30, to: firstLaunchDate) {
                                HStack {
                                    if iapManager.daysLeftBeforeIAP > 0 {
                                        Text(String(localized: "purchase_view_current_subscription_expires_in"))
                                            .font(.body)
                                            .bold()
                                            .foregroundColor(textColor)
                                        
                                        Text(date, style: .relative)
                                            .font(.body)
                                            .bold()
                                            .foregroundColor(textColor)
                                    } else {
                                        Text(String(localized: "purchase_view_current_subscription_expired_on"))
                                            .font(.body)
                                            .bold()
                                            .foregroundColor(textColor)
                                        
                                        Text(date, style: .date)
                                            .font(.body)
                                            .bold()
                                            .foregroundColor(textColor)
                                    }
                                }
                                .frame(minWidth: 0, maxWidth: .infinity, alignment: .leading)
                            }
                            
                            Text(String(localized: "purchase_view_current_why_subscribe"))
                                .font(.body)
                                .bold()
                                .foregroundColor(textColor)
                        }
                        HStack {
                            ForEach(iapManager.sortedSubscriptionKeysByPriceOptions) { product in
                                Button(action: {
                                    purchase(product: product)
                                }, label: {
                                    Text("\(product.displayPrice)\n\(product.displayName)")
                                        .foregroundColor(.white)
                                        .bold()
                                        .frame(maxWidth: .infinity)
                                        .contentShape(Rectangle())
                                        .frame(height: 65)
                                })
                                .padding()
                                .frame(maxWidth: .infinity)
                                .background(RoundedRectangle(cornerRadius: 10).fill(iapManager.colorForIAPButton(iapIdentifier: product.id)))
                            }
                        }
                    }
                    .padding([.leading, .trailing])
                    .frame(minWidth: 0, maxWidth: .infinity)
                    
                }
            }
        }
        .background(.ultraThinMaterial)
        .frame(minWidth: 0, maxWidth: .infinity)
        .background(.clear)
    }

    private var subscribedView: some View {
        VStack(alignment: .leading) {
            Text(String(localized: "purchase_view_current_subscription"))
                .font(.title3)
                .padding([.leading, .top])
            
            Divider()
            
            if let currentProduct = iapManager.currentSubscription,
               let value = iapManager.subscriptions[currentProduct] {
                HStack {
                    VStack (alignment: .leading, spacing: 10) {
                        Text(currentProduct.displayName)
                            .font(.title3)
                        Text(currentProduct.displayPrice)
                            .font(.title3)
                    }.padding([.leading, .trailing])
                    
                    ForEach(value!.status, id: \.self) { singleStatus in
                        StatusInfoView(product: currentProduct, status: singleStatus)
                            .padding([.leading])
                            .font(.body)
                    }
                }
            }
            
            Button(action: {
                showManageSubClosure?()
            }, label: {
                Text(String(localized: "purchase_view_cancel"))
                    .foregroundColor(.red)
            })
            .frame(maxWidth: .infinity)
            .padding([.bottom])
            .multilineTextAlignment(.center)
            
            Divider()
            
           showOtherSubOptions
        }
    }
    
    private var showOtherSubOptions: some View {
        VStack (spacing: 10) {
            HStack {
                ForEach(iapManager.sortedSubscriptionKeysByPriceOptions, id: \.self) { product in
                    if product.id != iapManager.nextRenewllOption?.id {
                        Button(action: {
                            purchase(product: product)
                        }, label: {
                            Text("\(product.displayPrice)\n\(product.displayName)")
                                .foregroundColor(.white)
                                .font(.headline)
                        })
                        .contentShape(Rectangle())
                        .padding()
                        .frame(maxWidth: .infinity)
                        .background(RoundedRectangle(cornerRadius: 10).fill(iapManager.colorForIAPButton(iapIdentifier: product.id)))
                    }
                }
            }
        }
        .padding([.leading, .trailing])
    }
    
    private func purchase(product: Product) {
        Task {
            try await iapManager.purchase(product)
        }
    }
}

struct PurchaseButtonView_Previews: PreviewProvider {
    static var previews: some View {
        PurchaseButtonView(iapManager: IAPManager())
    }
}