#nullable enable

using System.Linq;
using Demo2.Domain;
using NightShiftProtocol;
using NUnit.Framework;

namespace Demo2.Tests
{
    public sealed class Demo2DomainTests
    {
        [Test]
        public void BuiltInContent_HasFiveCyclesEighteenRulesAndFiveCategories()
        {
            var content = Demo2BuiltInContent.Create();

            Assert.That(content.Rules.Count, Is.EqualTo(18));
            Assert.That(content.Rules.Values.Select(rule => rule.Category).Distinct().Count(), Is.EqualTo(5));
            Assert.That(content.Waves.Select(wave => wave.TotalHealth), Is.EqualTo(new long[] { 500, 900, 1620, 2916, 5248 }));
            Assert.That(content.ComputeContentHash(), Has.Length.EqualTo(64));
        }

        [Test]
        public void SaturatingMath_ClampsBothDirectionsAndFormatsLargeValues()
        {
            Assert.That(SaturatingMath.Add(long.MaxValue, 1), Is.EqualTo(long.MaxValue));
            Assert.That(SaturatingMath.Add(long.MinValue, -1), Is.EqualTo(long.MinValue));
            Assert.That(SaturatingMath.Multiply(long.MaxValue, 2), Is.EqualTo(long.MaxValue));
            Assert.That(SaturatingMath.MultiplyScaled(200, 1500), Is.EqualTo(300));
            Assert.That(SaturatingMath.Format(1_250_000_000), Is.EqualTo("1.25e9"));
        }

        [Test]
        public void RuleOrder_IsStrictlyLeftToRight()
        {
            var rules = Demo2BuiltInContent.BuildRules().ToDictionary(rule => rule.Id);
            var initial = new Demo2RuleContext { Payload = 100, MultiplierMilli = 1000 };

            var addThenMultiply = Demo2RuleEngine.Evaluate(initial, new[] { rules["production.dense-ammo"], rules["machine.overclock"] });
            var multiplyThenAdd = Demo2RuleEngine.Evaluate(initial, new[] { rules["machine.overclock"], rules["production.dense-ammo"] });

            Assert.That(addThenMultiply.Payload, Is.EqualTo(420));
            Assert.That(multiplyThenAdd.Payload, Is.EqualTo(330));
            Assert.That(addThenMultiply.Faults, Is.EqualTo(1));
        }

        [Test]
        public void ConditionalRule_OnlyRunsWhenEveryFlagMatches()
        {
            var content = Demo2BuiltInContent.Create();
            var rule = content.Rules["logistics.long-haul"];
            var missesFaultCondition = new Demo2RuleContext { Payload = 100, MultiplierMilli = 1000, BeltBelowEightyPercent = true, Faults = 1 };
            var matches = missesFaultCondition;
            matches.Faults = 0;

            Assert.That(Demo2RuleEngine.Evaluate(missesFaultCondition, new[] { rule }).MultiplierMilli, Is.EqualTo(1000));
            Assert.That(Demo2RuleEngine.Evaluate(matches, new[] { rule }).MultiplierMilli, Is.EqualTo(1200));
        }

        [Test]
        public void NightShiftMod_AddsMachineRecipeAndConditionalRule()
        {
            var content = Demo2BuiltInContent.Create();
            var before = content.ComputeContentHash();

            new NightShiftContent().Register(content);

            Assert.That(content.Machines.ContainsKey(Demo2MachineKind.NightShiftSmelter), Is.True);
            Assert.That(content.Recipes.ContainsKey(100), Is.True);
            Assert.That(content.Rules.ContainsKey("night-shift.continuous-production"), Is.True);
            Assert.That(content.ComputeContentHash(), Is.Not.EqualTo(before));
        }
    }
}