namespace LivingVillage.Desktop.Tests

open Microsoft.VisualStudio.TestTools.UnitTesting
open Microsoft.Xna.Framework
open LivingVillage.Desktop

/// P79 夜帧整改回归（纯函数层）：
///  * 去叠光晕：单光源 ≤2 层视觉层（内芯 + 外环），芯/环之间确定暗隙，半径收紧到 3 tile；
///  * 夜帧炊烟增强：烟柱分段 + 外发光，夜帧 alpha 明显高于白天，白天零回归。
[<TestClass>]
type P79NightPolishTests () =

    let map = MapGen.generate (MapGen.defaultParams 42UL)

    [<TestMethod>]
    member _.HaloRingHasTwoVisualLayersAndADarkGap () =
        let cx, cy, radius, peak = 100, 100, 96, 118
        let layers = VillageArt.haloRingLayers cx cy radius peak
        Assert.IsTrue(not (List.isEmpty layers), "光晕须发出图元")
        Assert.IsTrue(
            (layers = VillageArt.haloRingLayers cx cy radius peak),
            "光晕须确定性")
        Assert.IsTrue((SceneDetail.nightHaloVisualLayers = 2), "每光源最多 2 层视觉层")
        let covers px py =
            layers
            |> List.exists (fun (rect, _) -> rect.X <= px && px < rect.X + rect.Width && rect.Y <= py && py < rect.Y + rect.Height)
        // 内芯亮、外环亮，芯环之间留一圈暗隙（同排 dy=0）。
        Assert.IsTrue(covers cx cy, "内芯须被点亮")
        Assert.IsTrue(covers (cx + 10) cy, "内芯直径内须被点亮")
        let innerRadius = radius * 2 / 5
        let gapRadius = max (innerRadius + 2) (radius * 3 / 5)
        let gapMid = cx + (innerRadius + gapRadius) / 2
        Assert.IsFalse(covers gapMid cy, "芯环之间须留暗隙")
        Assert.IsFalse(covers (cx - (gapMid - cx)) cy, "暗隙须左右对称")
        Assert.IsTrue(covers (cx + (gapRadius + radius) / 2) cy, "外环须被点亮")
        // 外环不得越过半径、不得出现方角。
        for (rect, _) in layers do
            Assert.IsTrue(abs (rect.X + rect.Width / 2 - cx) <= radius + 1, "图元须在半径内")
        Assert.IsFalse(covers (cx + radius) (cy + radius), "四角须保持为空：圆形非方斑")

    [<TestMethod>]
    member _.NightHaloIsTighterAndCapped () =
        Assert.IsTrue((SceneDetail.nightHaloRadiusTiles = 3), "去叠后半径须收紧到 3 tile")
        Assert.IsTrue((SceneDetail.nightHaloRadiusTiles < 4), "须比旧半径 4 tile 更紧")
        Assert.IsTrue((SceneDetail.nightHaloPeakAlphaAt 0.0f) = 0, "白天光晕须为 0（零回归）")
        Assert.IsTrue((SceneDetail.nightHaloPeakAlphaAt 1.0f) > 0, "夜帧光晕须可见")

    [<TestMethod>]
    member _.NightSmokeColumnAndGlowAreStrongerThanDay () =
        Assert.IsTrue((SceneDetail.nightSmokeSegments >= 2), "夜帧烟柱须分段堆叠")
        Assert.IsTrue((SceneDetail.nightSmokeSegmentLift > 0), "每段须向上抬升")
        Assert.IsTrue(
            (SceneDetail.nightSmokeAlphaAt 1.0f) > (SceneDetail.smokeAlphaAt 1.0f),
            "夜帧烟柱 alpha 须高于白天 underlay")
        Assert.IsTrue((SceneDetail.nightSmokeGlowPeakAt 1.0f) > (SceneDetail.nightSmokeGlowPeakAt 0.0f), "夜帧外发光须更强")
        Assert.IsTrue(SceneDetail.nightSmokeGlowRadius > 0, "外发光半径须为正")
        let sources = SceneDetail.smokeSourceTiles map
        Assert.IsTrue(not (List.isEmpty sources), "须仍能取到炊烟源")