using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using TransportGame.Model;
using TransportGame.Utils;
using UnityEngine;

namespace TransportGame.Generators
{
    public static class MapImageRenderer
    {
        [Flags]
        public enum Layers
        {
            None = 0,
            Elevation = 1,
            Grid = 2,
            Centers = 4,
            All = Elevation | Grid | Centers
        };

        private const int Scale = 20;

        /// <summary>
        /// Renders a map to a file
        /// </summary>
        /// <param name="file"></param>
        /// <param name="map"></param>
        /// <param name="layers"></param>
        //public static void Render(this Map map, string file, Layers layers = Layers.All)
        //{
        //    // Create texture on which to draw
        //    Texture2D texture = new Texture2D(
        //        map.Width * Scale,
        //        map.Height * Scale,
        //        TextureFormat.RGB24,
        //        false);

        //    // First layer - cells
        //    DrawCells(texture, map, (layers & Layers.Elevation) > 0, (layers & Layers.Centers) > 0);
            
        //    // Second layer - grid
        //    if ((layers & Layers.Grid) > 0)
        //        DrawGrid(texture, map);

        //    // Write to file
        //    File.WriteAllBytes(file + ".png", texture.EncodeToPNG());
        //}

        //private static void DrawCells(Texture2D texture, Map map, bool elevation, bool centers)
        //{
        //    for (int x = 0; x < map.Width; x++)
        //        for (int y = 0; y < map.Height; y++)
        //        {
        //            // Calculate scaled corners
        //            Vector2 c00 = new Vector2(
        //                map[x, y].Corner00.Pos.x * Scale,
        //                map[x, y].Corner00.Pos.y * Scale);
        //            Vector2 c01 = new Vector2(
        //                map[x, y].Corner01.Pos.x * Scale,
        //                map[x, y].Corner01.Pos.y * Scale);
        //            Vector2 c10 = new Vector2(
        //                map[x, y].Corner10.Pos.x * Scale,
        //                map[x, y].Corner10.Pos.y * Scale);
        //            Vector2 c11 = new Vector2(
        //                map[x, y].Corner11.Pos.x * Scale,
        //                map[x, y].Corner11.Pos.y * Scale);

        //            // Calculate color
        //            Color c = ColorHelper.FromArgb(0x555500);

        //            // Water - always blue
        //            if (map.IsWater(x, y))
        //                c = Color.blue;

        //            // Map type is elevation map - get elevation color
        //            else if (elevation)
        //                c = GetCollorOfTerrain(map[x, y].Elevation);

        //            // Draw polygon
        //            texture.FillPolygon(c, c00, c01, c11, c10);

        //            // Draw center
        //            if (centers)
        //                texture.DrawPoint(Color.red,
        //                    Convert.ToInt32(map[x, y].Center.x * Scale),
        //                    Convert.ToInt32(map[x, y].Center.y * Scale),
        //                    2);
        //        }
        //}

        //private static void DrawGrid(Texture2D texture, Map map)
        //{
        //    for (int x = 0; x < map.Width + 1; x++)
        //        for (int y = 0; y < map.Height + 1; y++)
        //        {
        //            Corner c0 = map.Corner(x, y);
        //            Vector2 c0pos = new Vector2(c0.Pos.x * Scale, c0.Pos.y * Scale);

        //            // Draw edges
        //            if (x > 0)
        //            {
        //                Corner c1 = map.Corner(x - 1, y);
        //                Vector2 c1pos = new Vector2(c1.Pos.x * Scale, c1.Pos.y * Scale);
        //                texture.DrawLine(Color.white, c0pos, c1pos);
        //            }
        //            if (y > 0)
        //            {
        //                Corner c1 = map.Corner(x, y - 1);
        //                Vector2 c1pos = new Vector2(c1.Pos.x * Scale, c1.Pos.y * Scale);
        //                texture.DrawLine(Color.white, c0pos, c1pos);
        //            }

        //            // Draw corner
        //            texture.DrawPoint(Color.white, c0pos, 2);
        //        }
        //}

        private static Color GetCollorOfTerrain(float height)
        {
            Color color1, color2;
            float alpha;

            if (height < 10f)
            {
                color1 = ColorHelper.FromArgb(0x00ffa2);
                color2 = ColorHelper.FromArgb(0xFCD628);
                alpha = height / 10f;
            }

            else if (height < 25f)
            {
                color1 = ColorHelper.FromArgb(0xFCD628);
                color2 = ColorHelper.FromArgb(0x9C6713);
                alpha = (height - 10f) / 15f;
            }

            else if (height < 50f)
            {
                color1 = ColorHelper.FromArgb(0xaaaaaa);
                color2 = ColorHelper.FromArgb(0xffffff);
                alpha = (height - 25f) / 25f;
            }
            else
            {
                color1 = color2 = Color.white;
                alpha = 1;
            }

            return Color.Lerp(color1, color2, alpha);
        }
    }
}