using System;
using Godot;

namespace AceField.Scripts.Effects;

public partial class CameraShake : Camera2D
{
    [Export] public float Decay = 0.8f;
    [Export] public Vector2 MaxOffset = new(100, 75);
    [Export] public float MaxRoll = 0.0f;
    [Export] public FastNoiseLite Noise;

    private float _noiseY = 0.0f;
    private float _trauma = 0.0f;
    private int _traumaExponent = 3;

    public override void _Ready()
    {
        GD.Randomize();
        Noise.Seed = (int)GD.Randi();
    }

    public override void _Process(double delta)
    {
        if (_trauma > 0)
        {
            _trauma = Mathf.Max(_trauma - Decay * (float)delta, 0);
            Shake();
        }
        else if (Offset.X != 0 || Offset.Y != 0 || Rotation != 0)
        {
            Mathf.Lerp(Offset.X, 0.0f, 1);
            Mathf.Lerp(Offset.Y, 0.0f, 1);
            Mathf.Lerp(Rotation, 0.0f, 1);
        }
    }

    private void Shake()
    {
        var amount = Mathf.Pow(_trauma, _traumaExponent);
        _noiseY++;
        Rotation = MaxRoll * amount * Noise.GetNoise2D(0, _noiseY);
        Offset = new Vector2(
            MaxOffset.X * amount * Noise.GetNoise2D(2000, _noiseY),
            MaxOffset.Y * amount * Noise.GetNoise2D(3000, _noiseY)
        );
    }

    public void AddTrauma(float amount)
    {
        _trauma = Mathf.Min(_trauma + amount, 1.0f);
    }
}