//
// Klak - Utilities for creative coding with Unity
//
// Copyright (C) 2016 Keijiro Takahashi
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
using UnityEngine;

namespace Klak.Math
{
    /// Noise generator that provides Vector3/Quaternion values
    struct NoiseGenerator
    {
        #region Private variables

        const float _fbmNorm = 1 / 0.75f;

        XXHash _hash1;
        XXHash _hash2;
        XXHash _hash3;

        int _fractal;
        float _frequency;
        float _time;

        #endregion

        #region Constructors

        public NoiseGenerator(float frequency)
        {
            _hash1 = XXHash.RandomHash;
            _hash2 = XXHash.RandomHash;
            _hash3 = XXHash.RandomHash;
            _fractal = 2;
            _frequency = frequency;
            _time = 0;
        }

        public NoiseGenerator(int seed, float frequency)
        {
            _hash1 = new XXHash(seed);
            _hash2 = new XXHash(seed ^ 0x1327495a);
            _hash3 = new XXHash(seed ^ 0x3cbe84f2);
            _fractal = 2;
            _frequency = frequency;
            _time = 0;
        }

        #endregion

        #region Public Properties And Methods

        public int FractalLevel {
            get { return _fractal; }
            set { _fractal = value; }
        }

        public float Frequency {
            get { return _frequency; }
            set { _frequency = value; }
        }

        public void Step()
        {
            _time += _frequency * Time.deltaTime;
        }

        #endregion

        #region Noise Functions

        public float Value01(int seed2)
        {
            var i1 = _hash1.Range(-100.0f, 100.0f, seed2);
            return Perlin.Fbm(_time + i1, _fractal) * _fbmNorm * 0.5f + 0.5f;
        }

        public float Value(int seed2)
        {
            var i1 = _hash1.Range(-100.0f, 100.0f, seed2);
            return Perlin.Fbm(_time + i1, _fractal) * _fbmNorm;
        }

        public Vector3 Vector(int seed2)
        {
            var i1 = _hash1.Range(-100.0f, 100.0f, seed2);
            var i2 = _hash2.Range(-100.0f, 100.0f, seed2);
            var i3 = _hash3.Range(-100.0f, 100.0f, seed2);
            return new Vector3(
                Perlin.Fbm(_time + i1, _fractal) * _fbmNorm,
                Perlin.Fbm(_time + i2, _fractal) * _fbmNorm,
                Perlin.Fbm(_time + i3, _fractal) * _fbmNorm);
        }

        public Quaternion Rotation(int seed2, float angle)
        {
            var i1 = _hash1.Range(-100.0f, 100.0f, seed2);
            var i2 = _hash2.Range(-100.0f, 100.0f, seed2);
            var i3 = _hash3.Range(-100.0f, 100.0f, seed2);
            return Quaternion.Euler(
                Perlin.Fbm(_time + i1, _fractal) * _fbmNorm * angle,
                Perlin.Fbm(_time + i2, _fractal) * _fbmNorm * angle,
                Perlin.Fbm(_time + i3, _fractal) * _fbmNorm * angle);
        }

        public Quaternion Rotation(int seed2, float rx, float ry, float rz)
        {
            var i1 = _hash1.Range(-100.0f, 100.0f, seed2);
            var i2 = _hash2.Range(-100.0f, 100.0f, seed2);
            var i3 = _hash3.Range(-100.0f, 100.0f, seed2);
            return Quaternion.Euler(
                Perlin.Fbm(_time + i1, _fractal) * _fbmNorm * rx,
                Perlin.Fbm(_time + i2, _fractal) * _fbmNorm * ry,
                Perlin.Fbm(_time + i3, _fractal) * _fbmNorm * rz);
        }

        #endregion
    }
}