using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Graphics;
using Newtonsoft.Json;
using RecrownedAthenaeum.Pipeline;
using RecrownedAthenaeum.Data;
using RecrownedAthenaeum.SpecialTypes;
using RecrownedAthenaeum.UI.Skin.Definitions;
using System;
using System.Collections.Generic;
using System.IO;

namespace RecrownedAthenaeum.UI.Skin
{
    /// <summary>
    /// Manages reference to default and loading of custom skins.
    /// </summary>
    public class SkinManager
    {
        private const string EXTENSION = ".rbskin";

        private readonly MergedSkin mergedSkin = new MergedSkin();

        /// <summary>
        /// the skin that favors the selected skin, but still has a fallback to the default skin in case anything is missing.
        /// </summary>
        public ISkin Skin { get { return mergedSkin; } }

        /// <summary>
        /// The user selected skin.
        /// </summary>
        public ISkin SelectedSkin { get { return mergedSkin.mainSkin; } set { mergedSkin.mainSkin = value; } }

        /// <summary>
        /// The fallback skin in case the selected skin doesn't cover a specific definition or color.
        /// </summary>
        public ISkin BaseSkin { get { return mergedSkin.alternateSkin; } set { mergedSkin.alternateSkin = value; } }

        /// <summary>
        /// The directory that contains the skins.
        /// </summary>
        public string skinsDirectory;

        List<string> skinPaths = new List<string>();

        /// <summary>
        /// Updates list of skins by searching recursively in the set <see cref="skinsDirectory"/>.
        /// </summary>
        public void SearchForSkins()
        {
            skinPaths.Clear();
            skinPaths = RecursiveSkinSearch(skinsDirectory);
        }

        /// <summary>
        /// Loads skin data if extension is valid.
        /// </summary>
        /// <param name="path">the path to load from.</param>
        /// <returns>A <see cref="SkinData"/> that holds all the information and some metadata for the loaded skin.</returns>
        public SkinData LoadSkinData(string path)
        {
            if (path.ToLower().EndsWith(EXTENSION))
            {
                return JsonConvert.DeserializeObject<SkinData>(File.ReadAllText(path));
            }
            throw new ArgumentException("The path given does not point to a file with the required extension \"" + EXTENSION + "\" rather, has \"" + Path.GetExtension(path) + "\".");
        }

        /// <summary>
        /// Generate skin from skin data.
        /// </summary>
        /// <param name="skinData">The skin data to generate skin from.</param>
        /// <param name="path">The path pointing to the file with the extension "<see cref="EXTENSION"/>".</param>
        /// <param name="graphicsDevice">The graphics device to generate the texture.</param>
        /// <returns>The skin generated from the skin data.</returns>
        public Skin GenerateSkinFromData(SkinData skinData, string path, GraphicsDevice graphicsDevice)
        {
            TextureAtlasDataReader textureAtlasDataReader = new TextureAtlasDataReader();
            FileInfo[] skinFiles = Directory.GetParent(path).GetFiles();
            Dictionary<string, string> fileNameWithPath = new Dictionary<string, string>();
            for (int i = 0; i < skinFiles.Length; i++)
            {
                fileNameWithPath.Add(skinFiles[i].Name, skinFiles[i].FullName);
            }
            TextureAtlasData atlasData = JsonConvert.DeserializeObject<TextureAtlasData>(fileNameWithPath[skinData.nameOfTextureAtlas]);
            Texture2D atlasTexture;
            using (FileStream stream = new FileStream(fileNameWithPath[atlasData.textureName], FileMode.Open))
            {
                atlasTexture = Texture2D.FromStream(graphicsDevice, stream);
            }
            TextureAtlas.Region[] regions = textureAtlasDataReader.GenerateAtlasRegionsFromData(atlasData, atlasTexture);
            TextureAtlas textureAtlas = new TextureAtlas(atlasTexture, regions);
            Texture2D cursorTexture;
            if (Path.HasExtension(skinData.cursorTextureName) && fileNameWithPath.ContainsKey(skinData.cursorTextureName))
            {
                using (FileStream stream = new FileStream(fileNameWithPath[skinData.cursorTextureName], FileMode.Open))
                {
                    cursorTexture = Texture2D.FromStream(graphicsDevice, stream);
                }
            } else
            {
                cursorTexture = textureAtlas[skinData.cursorTextureName].AsTexture2D(graphicsDevice);
            }
            Skin skin = new Skin(new TextureAtlas(atlasTexture, regions), cursorTexture);

            for (int i = 0; i < skinData.colors.Length; i++)
            {
                SkinData.ColorData colorData = skinData.colors[i];
                skin.AddColor(colorData.name, new Color(colorData.r, colorData.g, colorData.b, colorData.a));
            }

            for (int i = 0; i < skinData.definitions.Length; i++)
            {
                SkinData.DefinitionData definitionData = skinData.definitions[i];
                skin.AddDefinition(definitionData.name, definitionData.skin);
            }

            return skin;
        }

        private List<string> RecursiveSkinSearch(string path)
        {
            string[] files = Directory.GetFiles(path);
            string[] folders = Directory.GetDirectories(path);
            List<string> skins = new List<string>();
            for (int i = 0; i < files.Length; i++)
            {
                if (files[i].ToLower().EndsWith(EXTENSION))
                {
                    skins.Add(files[i]);
                }
            }
            for (int i = 0; i < folders.Length; i++)
            {
                skins.AddRange(RecursiveSkinSearch(folders[i]));
            }

            return skins;
        }

    }
}