using NUnit.Framework;
using BaseGames.Enemies.Navigation;

namespace BaseGames.Tests.EditMode.Enemies
{
    /// <summary>GroundNavigator 的方向/到达判定纯函数（无场景依赖）。</summary>
    public class GroundNavigatorLogicTests
    {
        [Test]
        public void Arrived_WhenWithinStopDistance()
            => Assert.IsTrue(GroundNavigator.Arrived(1.0f, 1.1f, 0.2f));

        // 边界含等号。刻意选二进制可精确表示的值(1.25-1.0 恰为 0.25)，
        // 否则如 1.2f-1.0f=0.20000005 会因浮点误差略大于 0.2f，测的就不是边界语义而是浮点噪声。
        [Test]
        public void Arrived_ExactlyAtStopDistance_True()
            => Assert.IsTrue(GroundNavigator.Arrived(1.0f, 1.25f, 0.25f));

        [Test]
        public void NotArrived_WhenOutsideStopDistance()
            => Assert.IsFalse(GroundNavigator.Arrived(1.0f, 1.5f, 0.2f));

        [Test]
        public void Arrived_IgnoresDirection()
        {
            Assert.IsTrue(GroundNavigator.Arrived(1.0f, 0.9f, 0.2f));   // 目标在左侧
            Assert.IsFalse(GroundNavigator.Arrived(1.0f, 0.5f, 0.2f));
        }

        [Test]
        public void WanderX_PositiveSign_LandsWithinForwardRange()
        {
            Assert.AreEqual(11.5f, GroundNavigator.WanderX(10f, 1.5f, 5f, +1f, 0f), 1e-4f);  // t=0 → 最近端
            Assert.AreEqual(15f,   GroundNavigator.WanderX(10f, 1.5f, 5f, +1f, 1f), 1e-4f);  // t=1 → 最远端
        }

        [Test]
        public void WanderX_NegativeSign_LandsWithinBackwardRange()
        {
            Assert.AreEqual(8.5f, GroundNavigator.WanderX(10f, 1.5f, 5f, -1f, 0f), 1e-4f);
            Assert.AreEqual(5f,   GroundNavigator.WanderX(10f, 1.5f, 5f, -1f, 1f), 1e-4f);
        }

        [Test]
        public void WanderX_MidT_Interpolates()
            => Assert.AreEqual(13.25f, GroundNavigator.WanderX(10f, 1.5f, 5f, +1f, 0.5f), 1e-4f);
    }
}