using System.Collections.Generic;
using CounterDrone.Core.Algorithms;
using CounterDrone.Core.Models;
using Xunit;

namespace CounterDrone.Core.Tests
{
    /// <summary>验证三阶段扩散模型下推荐算法的参数合理性</summary>
    public class DispersionAdvisorRealityTests
    {
        private ThreatProfile CreatePistonThreat(float speed = 200, float length = 20000)
        {
            return new ThreatProfile
            {
                Environment = new CombatScene { WindSpeed = 3, WindDirection = (int)WindDirection.W },
                Targets = new List<TargetConfig>
                {
                    new TargetConfig { PowerType = (int)PowerType.Piston, Quantity = 1,
                        TypicalSpeed = speed, TypicalAltitude = 500 },
                },
                Route = new RoutePlan { FormationMode = (int)FormationMode.Single },
                Waypoints = new List<Waypoint>
                {
                    new Waypoint { PosX = 0, PosY = 500, PosZ = 0 },
                    new Waypoint { PosX = length, PosY = 500, PosZ = 0 },
                },
            };
        }

        [Fact]
        public void Piston_200kmh_20km_ProducesReasonableSalvo()
        {
            var advisor = new DefaultDefenseAdvisor(DefaultAmmunition.GetAll());
            var rec = advisor.Recommend(CreatePistonThreat());

            // 基本断言
            Assert.Equal(AerosolType.InertGas, rec.Best.RecommendedAerosolType);
            Assert.True(rec.Best.SalvoRounds >= 1, $"齐射数={rec.Best.SalvoRounds}，应≥1");
            Assert.True(rec.Best.SalvoSpacing > 0, $"间隔={rec.Best.SalvoSpacing}m，应>0");
            Assert.True(rec.Best.RecommendedCloud.RecommendedTiming > 0,
                $"推荐时机={rec.Best.RecommendedCloud.RecommendedTiming}s，应>0");

            // 检查膨胀时间
            var ammo = DefaultAmmunition.GetByType(AerosolType.InertGas);
            var r0 = 3.3f * System.Math.Pow(ammo.BurstChargeKg, 0.32);
            var k = ammo.TurbulentExpansionK;
            var halfTime = 20000f / (200f / 3.6f) / 2f;
            var effectiveR = r0 + k * System.Math.Sqrt(System.Math.Min(halfTime, 30));
            if (halfTime > 30) effectiveR += k * System.Math.Sqrt(halfTime - 30) * 0.3f;

            // 膨胀应在合理范围
            Assert.True(effectiveR > 10, $"有效半径={effectiveR:F1}m，应>10m（初始{r0:F1}m）");
            Assert.True(effectiveR < 200, $"有效半径={effectiveR:F1}m，应<200m");
        }

        [Fact]
        public void Timing_AccountsForExpansion()
        {
            var advisor = new DefaultDefenseAdvisor(DefaultAmmunition.GetAll());
            var rec = advisor.Recommend(CreatePistonThreat());

            var timing = rec.Best.RecommendedCloud.RecommendedTiming!.Value;
            var halfTime = 20000f / (200f / 3.6f) / 2f;

            // 推荐时机应明显早于无人机到达中点（因为有飞行时间和膨胀时间）
            Assert.True(timing < halfTime - 5,
                $"推荐时机={timing:F1}s 应早于中点={halfTime:F1}s（预留飞行+膨胀时间）");
        }
    }
}