using Godot;
using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

public partial class CommandHandler : Node
{
	private Settings Settings { get; set; }
	private game Game { get; set; }
	private readonly List<Task> TaskQueue = new();
	private System.Net.Http.HttpClient _Client = null;
	private System.Net.Http.HttpClient Client
	{ get
		{
			_Client ??= new();
			return _Client;
		}
	}
	// Called when the node enters the scene tree for the first time.
	public override void _Ready()
	{
		Settings = GetNode<Settings>("/root/Settings");
		Game = GetNode<game>("/root/Game");
	}

	// Called every frame. 'delta' is the elapsed time since the previous frame.
	public override void _Process(double delta)
	{
		//delete/cleanup one finished task per frame
		//currently just logs errors
		var t = TaskQueue.FirstOrDefault(t => t.IsCompleted, null);
		if (t is not null)
		{
			if (t.Exception is not null)
				GD.PrintErr(t.Exception);
			TaskQueue.Remove(t);
		}
	}

	private void IncomingCommand(Command command)
	{
		if (!Settings.IsUserAuthorized(command.User, command.IsStreamer,
			command.IsModerator))
			return;
		var baseArgs = command.GetArgs();
		var type = CommandTypeHelper.ParseCommand(baseArgs.Pop());
		var args = baseArgs.DuplicateAtState();
		switch (type)
		{
			case CommandType.MoveCard:
				MoveCard(args);
				break;
			case CommandType.MoveRow:
				MoveRow(args);
				break;
			case CommandType.DeleteCard:
				DeleteCards(args);
				break;
			case CommandType.DeleteRow:
				DeleteRow(args);
				break;
			case CommandType.CreateCard:
				TaskQueue.Add(Task.Run(() => CreateCard(args)));
				break;
			case CommandType.CreateRow:
				CreateRow(args);
				break;
			case CommandType.RenameCard:
				RenameCard(args);
				break;
			case CommandType.RenameRow:
				RenameRow(args);
				break;
			case CommandType.RecolorRow:
				RecolorRow(args);
				break;
			case CommandType.ChangeCardImage:
				TaskQueue.Add(Task.Run(() => ChangeCardImage(args)));
				break;
			default:
				throw new Exception();
		}
	}

    private void MoveCard(CommandArguments args)
	{
		var cardId = args.Pop();
		var rowId = args.Pop();
		var indexStr = args.Pop();
        if (int.TryParse(indexStr, out int index))
            Game.MoveCard(cardId, rowId, index);
		else
			Game.MoveCard(cardId, rowId, null);
    }
	private void MoveRow(CommandArguments args)
	{
		var rowId = args.Pop();
		var newIndexStr = args.Pop();
		var newIndex = int.Parse(newIndexStr);
		Game.MoveRow(rowId, newIndex);
	}
	private void DeleteCards(CommandArguments args)
	{
		var ids = args.Enumerate().ToArray();
		Game.DeleteCards(ids);
	}
	private void DeleteRow(CommandArguments args)
	{
		var rowId = args.Pop();
		var deleteCards = args.Pop();
		if (bool.TryParse(deleteCards, out bool del))
			Game.DeleteRow(rowId, del);
		else
			Game.DeleteRow(rowId);
	}
	private async Task CreateCard(CommandArguments args)
	{
		var title = args.Pop();
		var url = args.Pop();
		Image img = await ImageFromUrl(url);
		Game.CreateCard(title, img);
	}
    private void CreateRow(CommandArguments args)
	{
		var colorStr = args.Pop();
		var title = args.Remaining();
		var color = Color.FromString(colorStr, new Color(0, 0, 0, 0));
		if (color == new Color(0, 0, 0, 0))
			Game.CreateRow(null, title);
		else
			Game.CreateRow(color, title);
	}
    private void RenameCard(CommandArguments args)
	{
		var cardId = args.Pop();
		var title = args.Remaining();
		Game.RenameCard(cardId, title);
	}
    private void RenameRow(CommandArguments args)
	{
		var rowId = args.Pop();
		var title = args.Remaining();
		Game.RenameRow(rowId, title);
	}
    private void RecolorRow(CommandArguments args)
	{
		var rowId = args.Pop();
		var colorStr = args.Pop();
		var color = Color.FromString(colorStr, new Color(0, 0, 0, 0));
		if (color == new Color(0, 0, 0, 0))
			throw new Exception($"invalid color {colorStr}");
		Game.RecolorRow(rowId, color);
	}
	private async Task ChangeCardImage(CommandArguments args)
    {
        var cardId = args.Pop();
		var img = await ImageFromUrl(args.Pop());
		Game.ChangeCardImage(cardId, img);
    }
	private async Task<Image> ImageFromUrl(string url)
	{
		var uri = new Uri(url);
		var resp = await Client.GetAsync(uri);
		if (!resp.IsSuccessStatusCode)
			return null;
		Image img = new();
		var arr = await resp.Content.ReadAsByteArrayAsync();
		//TODO detect images by header rather than extension
		switch (Path.GetExtension(uri.AbsolutePath).ToLower())
		{
			case "png":
				img.LoadPngFromBuffer(arr);
				break;
			case "jpg":
			case "jpeg":
				img.LoadJpgFromBuffer(arr);
				break;
			case "svg":
				img.LoadSvgFromBuffer(arr);
				break;
			case "webp":
				img.LoadWebpFromBuffer(arr);
				break;
			default:
				throw new Exception("unrecognized filetype");
		}
		return img;
	}
	protected override void Dispose(bool disposing)
	{
		if (disposing)
		{
			_Client?.Dispose();
		}
		base.Dispose(disposing);
	}
}