using System.Reflection;
using Godot;
using GdUnit4;
using static GdUnit4.Assertions;
using Movementtests.interfaces;
using Movementtests.systems.damage;

namespace Movementtests.tests;

[TestSuite, RequireGodotRuntime]
public class PlayerControllerUnitTest
{
    private PlayerController _player;

    [BeforeTest]
    public void SetupTest()
    {
        _player = new PlayerController();
        // We don't call _Ready() to avoid node dependency issues, 
        // but we need to initialize some private fields for unit testing.
        SetPrivateField(_player, "_targetSpeed", 7.0f);
        SetPrivateField(_player, "_gravity", 9.8f);
        
        // Setup Combat/Health dependencies
        var rHealth = new RHealth(100.0f);
        _player.RHealth = rHealth;
        _player.CHealth = new CHealth { RHealth = rHealth, CurrentHealth = 100.0f };
    }

    [AfterTest]
    public void CleanupTest()
    {
        _player?.Free();
    }

    private void SetPrivateField(object obj, string fieldName, object value)
    {
        var field = typeof(PlayerController).GetField(fieldName, BindingFlags.NonPublic | BindingFlags.Instance);
        field?.SetValue(obj, value);
    }

    [TestCase]
    public void TestCalculateGravityForce()
    {
        _player.Weight = 3.0f;
        // _gravity is 9.8f
        AssertFloat(_player.CalculateGravityForce()).IsEqualApprox(29.4f, 0.001f);
    }

    [TestCase]
    public void TestIsPlayerInputtingForward()
    {
        // Test Keyboard Input
        _player.InputDeviceChanged(false); // isUsingGamepad = false
        _player.OnInputMoveKeyboard(new Vector3(0, 0, -1)); // Forward is -Z in Godot
        AssertBool(_player.IsPlayerInputtingForward()).IsTrue();

        _player.OnInputMoveKeyboard(new Vector3(0, 0, 1)); // Backward
        AssertBool(_player.IsPlayerInputtingForward()).IsFalse();

        // Test Gamepad Input
        _player.InputDeviceChanged(true); // isUsingGamepad = true
        _player.OnInputMove(new Vector3(0, 0, -1));
        AssertBool(_player.IsPlayerInputtingForward()).IsTrue();
    }

    [TestCase]
    public void TestSetVerticalVelocity()
    {
        _player.Velocity = new Vector3(1, 0, 2);
        _player.SetVerticalVelocity(5.0f);
        AssertVector(_player.Velocity).IsEqual(new Vector3(1, 5, 2));
    }

    [TestCase]
    public void TestComputeHVelocityGround()
    {
        _player.Velocity = Vector3.Zero;
        _player.AccelerationFloor = 10.0f;
        
        // Moving forward
        Vector3 direction = Vector3.Forward; // (0, 0, -1)
        float delta = 0.1f;
        
        // _targetSpeed is 7.0f
        // Expected velocity change: Lerp(0, -7.0, 0.1 * 10.0) -> Lerp(0, -7.0, 1.0) -> -7.0
        Vector3 newVelocity = _player.ComputeHVelocity(delta, _player.AccelerationFloor, _player.DecelerationFloor, direction);
        
        AssertVector(newVelocity).IsEqual(new Vector3(0, 0, -7.0f));
    }

    [TestCase]
    public void TestComputeHVelocityAir()
    {
        _player.Velocity = new Vector3(5, 0, 0);
        _player.AccelerationAir = 2.0f;
        _player.DecelerationAir = 2.0f;
        
        // No input direction (deceleration)
        Vector3 direction = Vector3.Zero;
        float delta = 0.5f;
        
        // Expected velocity change: Lerp(5, 0, 0.5 * 2.0) -> Lerp(5, 0, 1.0) -> 0
        Vector3 newVelocity = _player.ComputeHVelocity(delta, _player.AccelerationAir, _player.DecelerationAir, direction);
        
        AssertVector(newVelocity).IsEqual(Vector3.Zero);
    }

    [TestCase]
    public void TestReduceHealth()
    {
        // Initial health is 100
        var damageRecord = new DamageRecord(Vector3.Zero, new RDamage(25.0f, EDamageTypes.Normal));
        _player.ReduceHealth(_player, damageRecord);
        
        AssertFloat(_player.CHealth.CurrentHealth).IsEqual(75.0f);
    }

    [TestCase]
    public void TestEmpoweredActionsLeft()
    {
        // EmpoweredActionsLeft setter calls PlayerUi.SetNumberOfDashesLeft
        // PlayerUi.SetNumberOfDashesLeft accesses _dashIcons array, which is null if _Ready() isn't called.
        // We can initialize _dashIcons via reflection to allow the setter to work.
        var mockUi = new PlayerUi();
        var dashIcons = new TextureRect[3] { new TextureRect(), new TextureRect(), new TextureRect() };
        var field = typeof(PlayerUi).GetField("_dashIcons", BindingFlags.NonPublic | BindingFlags.Instance);
        field?.SetValue(mockUi, dashIcons);
        
        _player.PlayerUi = mockUi;
        
        _player.EmpoweredActionsLeft = 2;
        AssertInt(_player.EmpoweredActionsLeft).IsEqual(2);
        AssertBool(dashIcons[0].Visible).IsTrue();
        AssertBool(dashIcons[1].Visible).IsTrue();
        AssertBool(dashIcons[2].Visible).IsFalse();
    }

    [TestCase]
    public void TestDashCooldownTimeout()
    {
        SetPrivateField(_player, "_canDash", false);
        _player.DashCooldownTimeout();
        bool canDash = (bool)GetPrivateField(_player, "_canDash");
        AssertBool(canDash).IsTrue();
    }

    private object GetPrivateField(object obj, string fieldName)
    {
        var field = typeof(PlayerController).GetField(fieldName, BindingFlags.NonPublic | BindingFlags.Instance);
        return field?.GetValue(obj);
    }

    [TestCase]
    public void TestGetInputLocalHDirection()
    {
        _player.InputDeviceChanged(false); // Keyboard
        _player.OnInputMoveKeyboard(new Vector3(1, 0, 1)); // Diagonal
        
        Vector3 expected = new Vector3(1, 0, 1).Normalized();
        AssertVector(_player.GetInputLocalHDirection()).IsEqualApprox(expected, new Vector3(0.001f, 0.001f, 0.001f));
    }

    [TestCase]
    public void TestComputeKnockback()
    {
        var cKnockback = new CKnockback();
        cKnockback.RKnockback = new RKnockback(10.0f);
        _player.CKnockback = cKnockback;
        
        // Setup knockback record
        var damageRecord = new DamageRecord(new Vector3(10, 0, 0), new RDamage(0, EDamageTypes.Normal));
        var knockbackRecord = new KnockbackRecord(damageRecord, 1.0f);
        
        _player.GlobalPosition = Vector3.Zero;
        cKnockback.GlobalPosition = Vector3.Zero;
        
        _player.RegisterKnockback(knockbackRecord);
        
        // Expected direction: GlobalPosition (0,0,0) - SourceLocation (10,0,0) = (-10,0,0)
        // Normalized: (-1, 0, 0)
        // finalKnockback: (-1, 0, 0) * 10.0 (Modifier) * 1.0 (ForceMultiplier) = (-10, 0, 0)
        
        Vector3 knockback = cKnockback.ComputeKnockback();
        AssertVector(knockback).IsEqual(new Vector3(-10, 0, 0));
    }
}