using UnityEngine;

namespace TT_TerrainTools
{
	public static class TT_TerrainHelpers
	{
		public enum EDirection
		{
			TOP = 0,
			BOTTOM = 1,
			LEFT = 2,
			RIGHT = 3
		}

		public static void FixBorders(Terrain p_terrainA, Terrain p_terrainB, EDirection p_borderA, EDirection p_borderB, float p_fade)
		{
			int heightmapResolution = p_terrainA.terrainData.heightmapResolution;
			if (p_terrainA.terrainData.heightmapResolution != heightmapResolution || p_terrainB.terrainData.heightmapResolution != heightmapResolution)
			{
				Debug.LogError("TT_Terrain9Patch: both TerrainData assets must have the same 'heightmapResolution'!");
				return;
			}
			p_fade = Mathf.Clamp01(p_fade);
			bool flag = false;
			bool flag2 = false;
			float y = p_terrainA.transform.position.y;
			float y2 = p_terrainA.terrainData.size.y;
			float y3 = p_terrainB.transform.position.y;
			float y4 = p_terrainB.terrainData.size.y;
			float[,] directedHeights = GetDirectedHeights(p_terrainA.terrainData, p_borderA);
			float[,] directedHeights2 = GetDirectedHeights(p_terrainB.terrainData, p_borderB);
			for (int i = 0; i < heightmapResolution; i++)
			{
				float directedWorldHeight = GetDirectedWorldHeight(i, p_borderA, directedHeights, p_terrainA);
				float directedWorldHeight2 = GetDirectedWorldHeight(i, p_borderB, directedHeights2, p_terrainB);
				float num = directedWorldHeight * (1f - p_fade) + directedWorldHeight2 * p_fade;
				SetDirectedWorldHeight(num, i, p_borderA, directedHeights, y, y2);
				SetDirectedWorldHeight(num, i, p_borderB, directedHeights2, y3, y4);
				flag = flag || num != directedWorldHeight;
				flag2 = flag2 || num != directedWorldHeight2;
			}
			if (flag)
			{
				SetDirectedHeights(directedHeights, p_terrainA.terrainData, p_borderA);
			}
			if (flag2)
			{
				SetDirectedHeights(directedHeights2, p_terrainB.terrainData, p_borderB);
			}
		}

		private static float GetDirectedWorldHeight(int p_index, EDirection p_border, float[,] p_heights, Terrain p_terrain)
		{
			return p_terrain.transform.position.y + p_terrain.terrainData.size.y * GetDirectedLocalHeight(p_index, p_border, p_heights);
		}

		private static float GetDirectedLocalHeight(int p_index, EDirection p_border, float[,] p_heights)
		{
			switch (p_border)
			{
			case EDirection.LEFT:
			case EDirection.RIGHT:
				return p_heights[p_index, 0];
			default:
				return p_heights[0, p_index];
			}
		}

		private static void SetDirectedWorldHeight(float p_value, int p_index, EDirection p_border, float[,] p_heights, float p_terrainPosY, float p_terrainSizeY)
		{
			float p_value2 = (p_value - p_terrainPosY) / p_terrainSizeY;
			SetDirectedLocalHeight(p_value2, p_index, p_border, p_heights);
		}

		private static void SetDirectedLocalHeight(float p_value, int p_index, EDirection p_border, float[,] p_heights)
		{
			switch (p_border)
			{
			case EDirection.LEFT:
			case EDirection.RIGHT:
				p_heights[p_index, 0] = p_value;
				break;
			default:
				p_heights[0, p_index] = p_value;
				break;
			}
		}

		private static float[,] GetDirectedHeights(TerrainData p_terrainData, EDirection p_border)
		{
			int heightmapResolution = p_terrainData.heightmapResolution;
			switch (p_border)
			{
			case EDirection.RIGHT:
				return p_terrainData.GetHeights(heightmapResolution - 1, 0, 1, heightmapResolution);
			case EDirection.LEFT:
				return p_terrainData.GetHeights(0, 0, 1, heightmapResolution);
			case EDirection.BOTTOM:
				return p_terrainData.GetHeights(0, 0, heightmapResolution, 1);
			default:
				return p_terrainData.GetHeights(0, heightmapResolution - 1, heightmapResolution, 1);
			}
		}

		private static void SetDirectedHeights(float[,] p_heights, TerrainData p_terrainData, EDirection p_border)
		{
			int heightmapResolution = p_terrainData.heightmapResolution;
			switch (p_border)
			{
			case EDirection.RIGHT:
				p_terrainData.SetHeights(heightmapResolution - 1, 0, p_heights);
				break;
			case EDirection.LEFT:
				p_terrainData.SetHeights(0, 0, p_heights);
				break;
			case EDirection.BOTTOM:
				p_terrainData.SetHeights(0, 0, p_heights);
				break;
			default:
				p_terrainData.SetHeights(0, heightmapResolution - 1, p_heights);
				break;
			}
		}
	}
}