using UnityEngine;
using Unity.Networking.Transport;
using Unity.Collections;

using UdpCNetworkDriver = Unity.Networking.Transport.UdpNetworkDriver;

public class Server : MonoBehaviour {
    private UdpCNetworkDriver driver = default;
    private NativeList<NetworkConnection> connections = default;

    private uint turn = 0;
    private static int cellID = -1;
    private static Color cellColor = Color.white;

    private void Start() {
        driver = new UdpCNetworkDriver(new INetworkParameter[0]);
        if (driver.Bind(NetworkEndPoint.Parse("0.0.0.0", 9000)) != 0) {
            ServerLog.Log("Failed to bind to port ...");
        }
        else {
            driver.Listen();
        }

        connections = new NativeList<NetworkConnection>(16, Allocator.Persistent);
    }

    private void Update() {
        driver.ScheduleUpdate().Complete();

        for (int i = 0; i < connections.Length; i++) {
            if (!connections[i].IsCreated) {
                connections.RemoveAtSwapBack(i);
                --i;
            }
        }

        NetworkConnection c;
        while ((c = driver.Accept()) != default) {
            connections.Add(c);
            ServerLog.Log("Accepted a connection");
        }

        DataStreamReader stream;
        uint currentAmountOfConnections = 0;
        for (int i = 0; i < connections.Length; i++) {
            if (connections[i] == default) continue;
            currentAmountOfConnections++;
        }

        for (int i = 0; i < connections.Length; i++) {
            if (connections[i] == default) continue;
            uint id = (uint)i + 1;

            NetworkEvent.Type cmd;
            while ((cmd = driver.PopEventForConnection(connections[i], out stream)) != NetworkEvent.Type.Empty) {
                if (cmd == NetworkEvent.Type.Data) {
                    DataStreamReader.Context readerCtx = default;
                    bool leftMouse = stream.ReadUInt(ref readerCtx) == 1;
                    bool rightMouse = stream.ReadUInt(ref readerCtx) == 1;
                    float xO = stream.ReadFloat(ref readerCtx);
                    float yO = stream.ReadFloat(ref readerCtx);
                    float zO = stream.ReadFloat(ref readerCtx);
                    float xD = stream.ReadFloat(ref readerCtx);
                    float yD = stream.ReadFloat(ref readerCtx);
                    float zD = stream.ReadFloat(ref readerCtx);

                    uint pressedKey = 0;

                    if (i == turn % currentAmountOfConnections) {
                        Ray ray = new Ray(new Vector3(xO, yO, zO), new Vector3(xD, yD, zD));
                        if (Physics.Raycast(ray, out RaycastHit hit)) {
                            cellID = hit.collider.GetComponent<Cell>().ID;
                            if (leftMouse) {
                                pressedKey = 1;
                                turn++;
                            }
                            else if (rightMouse) {
                                switch (id) {
                                    case 1: cellColor = Color.blue; break;
                                    case 2: cellColor = Color.red; break;
                                    case 3: cellColor = Color.green; break;
                                    case 4: cellColor = Color.yellow; break;
                                    default: cellColor = Color.black; break;
                                }
                                pressedKey = 2;
                                turn++;
                            }
                        }
                        ServerLog.Log("Turn {1}: Client{0}'s turn", id, turn);
                    }

                    using (var writer = new DataStreamWriter(28, Allocator.Temp)) {
                        writer.Write(id);
                        writer.Write(cellID);
                        writer.Write(pressedKey);
                        writer.Write(cellColor.r);
                        writer.Write(cellColor.g);
                        writer.Write(cellColor.b);
                        writer.Write(cellColor.a);
                        connections[i].Send(driver, writer);
                    }
                }
                else if (cmd == NetworkEvent.Type.Disconnect) {
                    ServerLog.Log("Client{0} has disconnected", id);
                }
            }
        }
    }

    public void OnDestroy() {
        driver.Dispose();
        connections.Dispose();
    }
}