using NUnit.Framework;
using BaseGames.Enemies;

namespace BaseGames.Tests.EditMode.Enemies
{
    /// <summary>
    /// EnemyBody 方向相关纯函数测试（无场景依赖）。
    /// 这三个函数的左右符号最易写反，故对两个方向与边界相等情形都做断言。
    /// </summary>
    public class EnemyBodyTests
    {
        // 身体占据 [2, 4]，中心 3，半宽 1
        const float MinX = 2f, MaxX = 4f;

        [Test]
        public void FrontEdge_Right_IsMaxX()
            => Assert.AreEqual(MaxX, EnemyBody.FrontEdge(MinX, MaxX, 1f));

        [Test]
        public void FrontEdge_Left_IsMinX()
            => Assert.AreEqual(MinX, EnemyBody.FrontEdge(MinX, MaxX, -1f));

        [Test]
        public void FrontEdge_ZeroDir_TreatedAsRight()
            => Assert.AreEqual(MaxX, EnemyBody.FrontEdge(MinX, MaxX, 0f));

        [Test]
        public void RearEdge_Right_IsMinX()
            => Assert.AreEqual(MinX, EnemyBody.RearEdge(MinX, MaxX, 1f));

        [Test]
        public void RearEdge_Left_IsMaxX()
            => Assert.AreEqual(MaxX, EnemyBody.RearEdge(MinX, MaxX, -1f));

        [Test]
        public void RearEdge_ZeroDir_TreatedAsRight()
            => Assert.AreEqual(MinX, EnemyBody.RearEdge(MinX, MaxX, 0f));

        // ── BodyPassed：向右 ─────────────────────────────────────────────
        [Test]
        public void BodyPassed_Right_NotReached_False()
            => Assert.IsFalse(EnemyBody.BodyPassed(MinX, MaxX, 5f, 1f));   // 目标在身体右侧外

        [Test]
        public void BodyPassed_Right_OverlappingTarget_False()
            => Assert.IsFalse(EnemyBody.BodyPassed(MinX, MaxX, 3f, 1f));   // 目标仍在身体内，未整体越过

        [Test]
        public void BodyPassed_Right_ExactlyAtRearEdge_True()
            => Assert.IsTrue(EnemyBody.BodyPassed(MinX, MaxX, 2f, 1f));    // 后缘恰好等于目标 = 已越过

        [Test]
        public void BodyPassed_Right_FullyPassed_True()
            => Assert.IsTrue(EnemyBody.BodyPassed(MinX, MaxX, 1f, 1f));

        // ── BodyPassed：向左 ─────────────────────────────────────────────
        [Test]
        public void BodyPassed_Left_NotReached_False()
            => Assert.IsFalse(EnemyBody.BodyPassed(MinX, MaxX, 1f, -1f));  // 目标在身体左侧外

        [Test]
        public void BodyPassed_Left_OverlappingTarget_False()
            => Assert.IsFalse(EnemyBody.BodyPassed(MinX, MaxX, 3f, -1f));

        [Test]
        public void BodyPassed_Left_ExactlyAtRearEdge_True()
            => Assert.IsTrue(EnemyBody.BodyPassed(MinX, MaxX, 4f, -1f));   // 后缘(max)恰好等于目标

        [Test]
        public void BodyPassed_Left_FullyPassed_True()
            => Assert.IsTrue(EnemyBody.BodyPassed(MinX, MaxX, 5f, -1f));
    }
}