using System.ComponentModel;
using SpdUp.Core;

namespace SpdUp.Tests;

/// <summary>
/// Tests for ObservableObject base class.
/// </summary>
public class ObservableObjectTests
{
    private sealed class TestObservable : ObservableObject
    {
        private string _name = string.Empty;
        public string Name
        {
            get => _name;
            set => SetProperty(ref _name, value);
        }

        private int _count;
        public int Count
        {
            get => _count;
            set => SetProperty(ref _count, value);
        }
    }

    [Fact]
    public void SetProperty_NewValue_RaisesPropertyChanged()
    {
        var obj = new TestObservable();
        string? changedProp = null;
        obj.PropertyChanged += (_, e) => changedProp = e.PropertyName;

        obj.Name = "hello";

        Assert.Equal("Name", changedProp);
        Assert.Equal("hello", obj.Name);
    }

    [Fact]
    public void SetProperty_SameValue_DoesNotRaisePropertyChanged()
    {
        var obj = new TestObservable { Name = "hello" };
        bool raised = false;
        obj.PropertyChanged += (_, _) => raised = true;

        obj.Name = "hello";

        Assert.False(raised);
    }

    [Fact]
    public void SetProperty_ReturnsTrue_WhenValueChanged()
    {
        var obj = new TestObservable();
        string? changedProp = null;
        obj.PropertyChanged += (_, e) => changedProp = e.PropertyName;

        obj.Count = 42;

        Assert.Equal("Count", changedProp);
        Assert.Equal(42, obj.Count);
    }

    [Fact]
    public void SetProperty_ReturnsFalse_WhenValueUnchanged()
    {
        var obj = new TestObservable { Count = 5 };
        bool raised = false;
        obj.PropertyChanged += (_, _) => raised = true;

        obj.Count = 5;

        Assert.False(raised);
    }

    [Fact]
    public void MultipleProperties_OnlyNotifyChanged()
    {
        var obj = new TestObservable();
        var notifications = new List<string>();
        obj.PropertyChanged += (_, e) => notifications.Add(e.PropertyName!);

        obj.Name = "a";
        obj.Count = 1;
        obj.Name = "a"; // same – no notification
        obj.Count = 2;

        Assert.Equal(3, notifications.Count);
        Assert.Equal(["Name", "Count", "Count"], notifications);
    }
}