//
//  AddView.swift
//  iExpense
//

import SwiftUI

struct AddView: View {
    @State private var name = ""
    @State private var type = "Personal"
    @State private var amount = ""
@Environment(\.presentationMode) var presentationMode
    static let types = ["Business", "Personal"]
    @ObservedObject var expenses: Expenses
    @State private var showAlert = false

    var body: some View {
        NavigationView {
            Form {
                TextField("Name", text: $name)
                Picker("Type", selection: $type) {
                    ForEach(Self.types, id: \.self) {
                        Text($0)
                    }
                }
                TextField("Amount", text: $amount)
                    .keyboardType(.numberPad)
            }
            .navigationBarTitle("Add new expense")
            .navigationBarItems(trailing: Button("Save") {
                if let actualAmount = Int(self.amount) {
                    let item = ExpenseItem(name: self.name, type: self.type, amount: actualAmount)
                    self.expenses.items.append(item)
                    self.presentationMode.wrappedValue.dismiss()
                }
                else {
                    self.showAlert = true
                }

            })
                .alert(isPresented: $showAlert){
                    Alert(title: Text("Warning!"), message: Text("Something went wrong"), dismissButton: .default(Text("OK")))
            }
        }
    }
}

struct AddView_Previews: PreviewProvider {
    static var previews: some View {
        AddView(expenses: Expenses())
    }
}

//
//  ContentView.swift
//  iExpense
//

import SwiftUI

struct ExpenseItem: Identifiable,Codable {
    let id = UUID()
    let name: String
    let type: String
    let amount: Int
}

class Expenses: ObservableObject {
    @Published var items: [ExpenseItem] {
        didSet {
            let encoder = JSONEncoder()
            if let encoded = try? encoder.encode(items) {
                UserDefaults.standard.set(encoded, forKey: "Items")
            }
        }
    }
    init() {
        if let items = UserDefaults.standard.data(forKey: "Items") {
            let decoder = JSONDecoder()
            if let decoded = try? decoder.decode([ExpenseItem].self, from: items) {
                self.items = decoded
                return
            }
        }

        self.items = []
    }
}

struct style: ViewModifier{
    var amount: Int

    func body(content: Content) -> some View {
        if amount < 10 {
            return content.foregroundColor(.red)
        }

        else if amount < 100 {
            return content.foregroundColor(.green)
        }

        else if amount > 100{
            return content.foregroundColor(.blue)
        }

        else {
            return content.foregroundColor(.black)
        }
    }
}

struct ContentView: View {
    @State private var showingAddExpense = false
    @ObservedObject var expenses = Expenses()

    var body: some View {
        NavigationView {
            List {
                ForEach(expenses.items) { item in
                    HStack {
                        VStack(alignment: .leading) {
                            Text(item.name)
                                .font(.headline)
                            Text(item.type)
                        }

                        Spacer()
                        Text("$\(item.amount)")
                            .modifier(style(amount: item.amount))
                    }
                }
                .onDelete(perform: removeItems)
            }
            .navigationBarItems(leading: EditButton(), trailing: Button(action: {
                self.showingAddExpense = true
            }) {
                Image(systemName: "plus")
            })
                .sheet(isPresented: $showingAddExpense) {
                    AddView(expenses: self.expenses)
            }
            .navigationBarTitle("iExpense")
        }
    }

    func removeItems(at offsets: IndexSet) {
        expenses.items.remove(atOffsets: offsets)
    }

}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

do you have a question about your code? btw I had a read on your code as I am doing the same project. Thanks for the code on ViewModifier, I was stuck in a challenge on changing $ color!

Text("$\(item.cost)")
                            .foregroundColor(item.cost <= 100 ? .green : item.cost > 100 && item.cost < 1000 ? .orange : .red)

Hey guys this replaces your multiple line code to only two :)

Thanks for posting some code everyone, seeing other approaches after a while of trying myself and not being sure how to approach it myself, is a great learning tool. Only after I bang my head against the wall a bit first :).

How would you remove Amount alltogether?