using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Net.Sockets;
using System.Text;

namespace IdleMafiaBot
{

    static class Bridge
    {
#if LINUX
        public static readonly bool On = true;
#elif OCRBRIDGE
        public static readonly bool On = !string.IsNullOrEmpty(Environment.GetEnvironmentVariable("OCR_BRIDGE"));
#else
        public const bool On = false;
#endif
        static TcpClient client;
        static NetworkStream net;
        static StreamReader reader;
        static readonly object gate = new object();

        public struct Item { public string Text; public double X, Y, W, H; }

        static int Port
        {
            get
            {
                int p;
                return int.TryParse(Environment.GetEnvironmentVariable("OCR_BRIDGE"), out p) ? p : 8765;
            }
        }

        static void Connect()
        {
            client = new TcpClient("127.0.0.1", Port) { NoDelay = true };
            client.ReceiveTimeout = 120000;
            net = client.GetStream();
            reader = new StreamReader(net, new UTF8Encoding(false));
        }

        static void Close()
        {
            try { if (client != null) client.Close(); } catch (Exception) { }
            client = null;
            net = null;
            reader = null;
        }

        public static List<Item> Ask(byte[] bgra, int w, int h)
        {
            lock (gate)
            {
                try { return Once(bgra, w, h); }
                catch (Exception) { Close(); }
                try { return Once(bgra, w, h); }
                catch (Exception) { Close(); throw; }
            }
        }

        static string Line()
        {
            var line = reader.ReadLine();
            if (line == null) throw new IOException("the reader closed the connection");
            return line;
        }

        static List<Item> Once(byte[] bgra, int w, int h)
        {
            if (client == null) Connect();
            var head = new byte[8];
            BitConverter.GetBytes(w).CopyTo(head, 0);
            BitConverter.GetBytes(h).CopyTo(head, 4);
            net.Write(head, 0, 8);
            net.Write(bgra, 0, w * 4 * h);
            net.Flush();
            int n = int.Parse(Line(), CultureInfo.InvariantCulture);
            var list = new List<Item>();
            for (int i = 0; i < n; i++)
            {
                var line = Line();
                int tab = line.IndexOf('\t');
                var p = line.Substring(0, tab).Split(' ');
                list.Add(new Item
                {
                    X = double.Parse(p[0], CultureInfo.InvariantCulture), Y = double.Parse(p[1], CultureInfo.InvariantCulture),
                    W = double.Parse(p[2], CultureInfo.InvariantCulture), H = double.Parse(p[3], CultureInfo.InvariantCulture),
                    Text = line.Substring(tab + 1),
                });
            }
            return list;
        }

        public static string Check()
        {
            try { Ask(new byte[16 * 16 * 4], 16, 16); return null; }
            catch (Exception e) { return "The text reader doesn't answer on port " + Port + " (" + e.Message + "), so the bot can't read the game."; }
        }
    }
}