using OpenMetaverse;
using OpenSim.Region.Framework.Scenes;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace OpenSim.Modules.PathFinding
{
    class PathFinder
    {
        private UUID m_requestID = UUID.Zero;

        private Scene m_scene = null;
        private Bitmap m_bitmap = null;

        public PathFinder(UUID requestID, Scene localScene)
        {
            m_requestID = requestID;

            m_scene = localScene;

            m_bitmap = new Bitmap((int)m_scene.RegionInfo.RegionSizeX, (int)m_scene.RegionInfo.RegionSizeY);
        }

        public void preparePathFindingScene(bool terrain)
        {
            convertRegionToBitmap(terrain);
        }

        public void setPositions(Vector2 start, Vector2 target)
        {
            m_bitmap.SetPixel(m_bitmap.Size.Width - (int)start.Y, m_bitmap.Size.Height - (int)start.X, Color.Green);
            m_bitmap.SetPixel(m_bitmap.Size.Width - (int)target.Y, m_bitmap.Size.Height - (int)target.X, Color.Red);
            saveDebugImageToDisc();
        }

        private void convertRegionToBitmap(bool terrain)
        {
            if (terrain == true)
            {
                for (int X = 0; X < m_scene.RegionInfo.RegionSizeX; X++)
                {
                    for (int Y = 0; Y < m_scene.RegionInfo.RegionSizeY; Y++)
                    {
                        float baseheight = (float)m_scene.Heightmap[(int)m_scene.RegionInfo.RegionSizeX - X, (int)m_scene.RegionInfo.RegionSizeY - Y];

                        //Block the position then water is on this place.
                        if (baseheight <= m_scene.RegionInfo.RegionSettings.WaterHeight)
                            m_bitmap.SetPixel(X, Y, Color.Black);

                        //Allow all positions they have terrain over the water height.
                        if (baseheight > m_scene.RegionInfo.RegionSettings.WaterHeight)
                            m_bitmap.SetPixel(X, Y, Color.White);
                    }
                }
            }
            else
            {
                for (int X = 0; X < m_scene.RegionInfo.RegionSizeX; X++)
                {
                    for (int Y = 0; Y < m_scene.RegionInfo.RegionSizeY; Y++)
                    {
                        m_bitmap.SetPixel(X, Y, Color.Black);
                    }
                }
            }

            PathFindingSceneGenerator.DrawObjectVolume(m_scene, ref m_bitmap);
        }


        private void saveDebugImageToDisc()
        {
            m_bitmap.Save(m_requestID + ".png", ImageFormat.Png);
        }
    }
}