// Based on:
// https://github.com/UnknownShadow200/ClassicalSharp/wiki/Minecraft-Classic-map-generation-algorithm
// Thanks to Jerralish for originally reverse engineering classic's algorithm, then preparing a high level overview of the algorithm.
// I believe this process adheres to clean room reverse engineering.
using System;

namespace ClassicalSharp.Generator {
	
	// TODO: figure out how noise functions differ, probably based on rnd.
	public class NotchyGenerator {
		
		int width, height, length;
		int waterLevel;
		byte[] blocks;
		short[] heightmap;
		
		public byte[] GenerateMap( int width, int height, int length ) {
			this.width = width;
			this.height = height;
			this.length = length;
			waterLevel = height / 2;
			blocks = new byte[width * height * length];
			
			CreateHeightmap();
			CreateStrata();
			return null;
		}
		
		void CreateHeightmap() {
			Noise n1 = new CombinedNoise(
				new OctaveNoise( 8 ), new OctaveNoise( 8 ) );
			Noise n2 = new CombinedNoise(
				new OctaveNoise( 8 ), new OctaveNoise( 8 ) );
			Noise n3 = new OctaveNoise( 6 );
			int index = 0;
			short[] map = new short[width * length];
			
			for( int z = 0; z < length; z++ ) {
				for( int x = 0; x < width; x++ ) {
					double hLow = n1.Compute( x * 1.3f, z * 1.3f ) / 6 - 4;
					double hHigh = n2.Compute( x * 1.3f, z * 1.3f ) / 5 + 6;
					
					double height = n3.Compute( x, z ) > 0 ? hLow : Math.Max( hLow, hHigh );
					if( height < 0 ) height *= 0.8f;
					map[index++] = (short)(height + waterLevel);
				}
			}
			heightmap = map;
		}
		
		void CreateStrata() {
			Noise n = new OctaveNoise( 8 );
			
			int mapIndex = 0;
			for( int z = 0; z < length; z++ ) {
				for( int x = 0; x < width; x++ ) {
					int dirtThickness = (int)(n.Compute( x, z ) / 24 - 4);
					int dirtHeight = heightmap[mapIndex];
					int stoneHeight = dirtHeight + dirtThickness;
					
					for( int y = 0; y < height; y++ ) {
						
					}
					mapIndex++;
				}
			}
		}
	}
}