import Foundation

struct AppState {
    var session = SessionState()
    var profile = ProfileState()
    var cart = CartState()
    var address = AddressState()
    var favorites = FavoritesState()
    var activeModal: AppModal? = nil
}

enum AppModal: String, Identifiable {
    case addressPicker
    case filters

    var id: String { rawValue }
}

struct SessionState {
    var isAuthenticated: Bool = false
    var jwt: String? = nil
}

struct ProfileState {
    var id: String? = nil
    var name: String = ""
    var email: String = ""
    var phone: String = ""
}

struct AddressState {
    var selectedId: String? = nil
    var display: String = "Defina seu endereco"
    var latitude: Double? = nil
    var longitude: Double? = nil
    var onboardingMessage: String? = nil
}

struct FavoritesState {
    var storeIds: Set<String> = []
}

struct CartState {
    var storeId: String? = nil
    var storeName: String? = nil
    var items: [CartItemState] = []
    var total: Double = 0
}

struct CartItemState: Identifiable {
    let id: String
    var productId: String
    var storeId: String
    var name: String
    var imageURL: String? = nil
    var details: String? = nil
    var addons: [CartItemAddonState] = []
    var quantity: Int
    var unitPrice: Double
}

struct CartItemAddonState: Identifiable, Hashable {
    let id: String
    var name: String
    var quantity: Int
    var unitPrice: Double
}

extension CartState {
    var totalItems: Int {
        items.reduce(0) { $0 + $1.quantity }
    }

    mutating func recalculateTotal() {
        total = items.reduce(0) { $0 + (Double($1.quantity) * $1.unitPrice) }
    }

    mutating func clear() {
        storeId = nil
        storeName = nil
        items = []
        total = 0
        SessionStateStore.clearCart()
    }

    mutating func add(item: CartItemState) {
        if let index = items.firstIndex(where: { $0.id == item.id }) {
            items[index].quantity += item.quantity
        } else {
            items.append(item)
        }
        recalculateTotal()
        SessionStateStore.saveCart(self)
    }

    mutating func set(item: CartItemState) {
        if let index = items.firstIndex(where: { $0.id == item.id }) {
            if item.quantity <= 0 {
                items.remove(at: index)
            } else {
                items[index] = item
            }
        } else if item.quantity > 0 {
            items.append(item)
        }

        if items.isEmpty {
            storeId = nil
            storeName = nil
        }
        recalculateTotal()
        if items.isEmpty {
            SessionStateStore.clearCart()
        } else {
            SessionStateStore.saveCart(self)
        }
    }

    mutating func increment(itemId: String) {
        guard let index = items.firstIndex(where: { $0.id == itemId }) else { return }
        items[index].quantity += 1
        recalculateTotal()
        SessionStateStore.saveCart(self)
    }

    mutating func decrement(itemId: String) {
        guard let index = items.firstIndex(where: { $0.id == itemId }) else { return }
        items[index].quantity -= 1
        if items[index].quantity <= 0 {
            items.remove(at: index)
        }
        if items.isEmpty {
            storeId = nil
            storeName = nil
        }
        recalculateTotal()
        if items.isEmpty {
            SessionStateStore.clearCart()
        } else {
            SessionStateStore.saveCart(self)
        }
    }

    func toOrderItemsPayload() -> [CreateOrderItemPayload] {
        items.map { item in
            CreateOrderItemPayload(
                productId: item.productId,
                name: item.name,
                qty: item.quantity,
                price: item.unitPrice,
                addons: item.addons
                    .filter { $0.quantity > 0 }
                    .map {
                        CreateOrderAddonPayload(
                            addonId: $0.id,
                            name: $0.name,
                            qty: $0.quantity,
                            price: $0.unitPrice
                        )
                    }
            )
        }
    }
}