using PkmnLib.Dynamic.Models;
using PkmnLib.Plugin.Gen7.Scripts.Moves;

namespace PkmnLib.Plugin.Gen7.Tests.Scripts.Moves;

/// <summary>
/// Tests for the <see cref="HeatCrash"/> move script.
/// Gen VII Bulbapedia behavior: "Heat Crash deals damage. Its power depends on the weight of both the user
/// and the target; the greater the difference between the user's weight and the target's weight, the
/// greater the power." The power table by the target's weight relative to the user is: more than 50% → 40,
/// 33.35%–50% → 60, 25.01%–33.34% → 80, 20.01%–25% → 100, 20% or less → 120.
/// </summary>
public class HeatCrashTests
{
    private static (HeatCrash script, IExecutingMove move, IPokemon target) CreateTestSetup(float userWeightInKg,
        float targetWeightInKg)
    {
        var script = new HeatCrash();
        var move = Substitute.For<IExecutingMove>();
        var user = Substitute.For<IPokemon>();
        user.WeightInKg.Returns(userWeightInKg);
        move.User.Returns(user);
        var target = Substitute.For<IPokemon>();
        target.WeightInKg.Returns(targetWeightInKg);
        return (script, move, target);
    }

    /// <summary>
    /// Bulbapedia weight/power table: target more than 50% of the user's weight → 40,
    /// 33.35%–50% → 60, 25.01%–33.34% → 80, 20.01%–25% → 100, 20% or less → 120.
    /// Each bracket is tested with values inside the bracket on both sides.
    /// </summary>
    [Test, Arguments(50f, 100f, (ushort)40), Arguments(100f, 100f, (ushort)40), Arguments(190f, 100f, (ushort)40),
     Arguments(210f, 100f, (ushort)60), Arguments(290f, 100f, (ushort)60), Arguments(310f, 100f, (ushort)80),
     Arguments(390f, 100f, (ushort)80), Arguments(410f, 100f, (ushort)100), Arguments(490f, 100f, (ushort)100),
     Arguments(510f, 100f, (ushort)120), Arguments(1000f, 100f, (ushort)120)]
    // target heavier than the user
    // equal weight (100%)
    // target at ~52.6%
    // target at ~47.6%
    // target at ~34.5%
    // target at ~32.3%
    // target at ~25.6%
    // target at ~24.4%
    // target at ~20.4%
    // target at ~19.6%
    // target at 10%
    public async Task ChangeBasePower_WeightRatio_SetsBasePowerFromWeightTable(float userWeightInKg,
        float targetWeightInKg, ushort expectedPower)
    {
        // Arrange
        var (script, move, target) = CreateTestSetup(userWeightInKg, targetWeightInKg);
        ushort basePower = 1;

        // Act
        script.ChangeBasePower(move, target, 0, ref basePower);

        // Assert
        await Assert.That(basePower).IsEqualTo(expectedPower);
    }

    /// <summary>
    /// Bulbapedia weight/power table boundaries: the brackets are "33.35% - 50%" → 60,
    /// "25.01% - 33.34%" → 80, "20.01% - 25%" → 100 and "20% or less" → 120, so a target weighing
    /// exactly 50%, one third, 25% or 20% of the user belongs to the higher-power bracket.
    /// </summary>
    [Test, Arguments(200f, 100f, (ushort)60), Arguments(300f, 100f, (ushort)80), Arguments(400f, 100f, (ushort)100),
     Arguments(500f, 100f, (ushort)120)]
    // target at exactly 50%
    // target at exactly one third (33.33% ≤ 33.34%)
    // target at exactly 25%
    // target at exactly 20%
    public async Task ChangeBasePower_ExactBracketBoundary_UsesHigherPowerBracket(float userWeightInKg,
        float targetWeightInKg, ushort expectedPower)
    {
        // Arrange
        var (script, move, target) = CreateTestSetup(userWeightInKg, targetWeightInKg);
        ushort basePower = 1;

        // Act
        script.ChangeBasePower(move, target, 0, ref basePower);

        // Assert
        await Assert.That(basePower).IsEqualTo(expectedPower);
    }

    /// <summary>
    /// Bulbapedia: "Its power depends on the weight of both the user and the target" — the base power is
    /// derived from the weight ratio alone, fully replacing the incoming base power value.
    /// </summary>
    [Test]
    public async Task ChangeBasePower_HighIncomingBasePower_IsReplacedByWeightTableValue()
    {
        // Arrange
        var (script, move, target) = CreateTestSetup(100f, 100f);
        ushort basePower = 250;

        // Act
        script.ChangeBasePower(move, target, 0, ref basePower);

        // Assert
        await Assert.That(basePower).IsEqualTo((ushort)40);
    }
}