using System;
using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;
using UnityEngine;

namespace Omni
{
    public enum SecureAuthenticationProtocolState { SAPEnabled, SAPDisabled, SAPError };

    public class OmniConnectionComponent : MonoBehaviour
    {
        public delegate IntPtr WndProcDelegate(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam);

        private OmniManager omniManager;
        private OmniDataComponent omniDataComponent;

        private SecureAuthenticationProtocolState mySAPStatus = SecureAuthenticationProtocolState.SAPError;
        private int SAPErrorChecks = 0;

        //Has the Omni been found
        [HideInInspector]
        public bool omniFound = false;

        public void Connect(OmniDataComponent dataComponent)
        {
            omniDataComponent = dataComponent;
            Start_TryingtoReconnect();
        }

        #region reconnecting logic
        IntPtr hMainWindow;
        IntPtr oldWndProcPtr;
        IntPtr newWndProcPtr;
        WndProcDelegate newWndProc;
        bool isrunning = false;

        [DllImport("user32.dll", CharSet = CharSet.Auto, ExactSpelling = true)]
        public static extern System.IntPtr GetForegroundWindow();

        [DllImport("user32.dll")]
        static extern IntPtr SetWindowLongPtr(IntPtr hWnd, int nIndex, IntPtr dwNewLong);

        [DllImport("user32.dll")]
        static extern IntPtr CallWindowProc(IntPtr lpPrevWndFunc, IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

        IntPtr wndProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam)
        {
            if (msg == 0x0219)
            {
                //Debug.LogError("Event Triggered; " + wParam.ToInt32());// + "; " + lParam.ToInt32());
                switch (wParam.ToInt32())
                {
                    case 0x8000: // DBT_DEVICEARRIVAL
                                 //case 0x8004: // DBT_DEVICEREMOVECOMPLETE
                                 //case 0x0007: // DBT_DEVNODES_CHANGED:
                        AttemptToReconnectTheOmni();
                        break;
                }
            }
            return CallWindowProc(oldWndProcPtr, hWnd, msg, wParam, lParam);
        }
        #endregion

        void AttemptToReconnectTheOmni()
        {
            if (omniManager == null)
                omniManager = new OmniManager();

            if (!omniManager.omniDisconnected)
                return;

            if (omniManager.FindOmni())
            {
                Debug.Log(System.DateTime.Now.ToLongTimeString() + ": OmniConnectionComponent(AttemptToReconnectTheOmni) - Successfully found the Omni for reconnect.");
                omniFound = true;
            }
            else
            {
                Debug.LogError(System.DateTime.Now.ToLongTimeString() + ": OmniConnectionComponent(AttemptToReconnectTheOmni) - Attempted to Reconnect the Omni, but Omni not found.");
                omniFound = false;
                return;
            }
        }

        void Start_TryingtoReconnect()
        {
            if (isrunning) return;

            hMainWindow = GetForegroundWindow();
            newWndProc = new WndProcDelegate(wndProc);
            newWndProcPtr = Marshal.GetFunctionPointerForDelegate(newWndProc);
            oldWndProcPtr = SetWindowLongPtr(hMainWindow, -4, newWndProcPtr);
            isrunning = true;
        }

        public void StopReconnectAttempts()
        {
            // Disable the reconnect attempting
            Debug.Log(System.DateTime.Now.ToLongTimeString() + ": OmniConnectionComponent(OnDisable) - Uninstall Hook");
            if (!isrunning) return;
            SetWindowLongPtr(hMainWindow, -4, oldWndProcPtr);
            hMainWindow = IntPtr.Zero;
            oldWndProcPtr = IntPtr.Zero;
            newWndProcPtr = IntPtr.Zero;
            newWndProc = null;
            isrunning = false;
        }

        public IEnumerator ConfigureOmniConnect()
        {
            yield return new WaitForSeconds(3f);
            StartCoroutine(SetGameMode());
            SAPErrorChecks = 0;
            mySAPStatus = SecureAuthenticationProtocolState.SAPError;
            StartCoroutine(VerifySAP());
            yield return new WaitForSeconds(10f);
            string systemReadyCheckUrl = "http://localhost:8085/systemReady";
            string systemReadyWebResponse = "-1";
            yield return StartCoroutine(OmniConnectWebRequest.CoroutineGetRequest(systemReadyCheckUrl, value => systemReadyWebResponse = value));
            if (systemReadyWebResponse.Contains("OK;Secure;MotionDisabled"))
            {
                Debug.LogError("Authentication Protocol Failed. Your Omni is not registered and therefore cannot be enabled. Please contact your Omni provider to register your Omni.");
            }
        }

        private IEnumerator VerifySAP()
        {
            SecureAuthenticationProtocolState SAPGetResponse = SecureAuthenticationProtocolState.SAPError;
            yield return StartCoroutine(GetSecureAuthentication(value => SAPGetResponse = value));
            mySAPStatus = SAPGetResponse;

            if (mySAPStatus == SecureAuthenticationProtocolState.SAPEnabled)
            {
                Debug.Log("SAP Enabled. Initializing SDK.");
                /* For Initialization to work, you must create a developer account, and register your game with Virtuix by
                 * emailing your Omni provider. Please provide the serial number for any Omnis that you wish to use for development.*/
                OVSDK.Init(1000, "01ec17dac7140c0fbe936ee128310000", "omni=1");
                omniDataComponent.ResetHasSetCouplingPercentage();
            }
            else if (mySAPStatus == SecureAuthenticationProtocolState.SAPDisabled)
            {
                Debug.Log("SAP Disabled.");
                omniDataComponent.ResetHasSetCouplingPercentage();
            }
            else
            {
                if (SAPErrorChecks < 3)
                {
                    SAPErrorChecks++;
                    yield return new WaitForSeconds(2f);
                    StartCoroutine(VerifySAP());
                }
                else
                {
                    Debug.LogError("There is an error with your configuration in Omni Connect. Ensure that Omni Connect is installed and running on your system. " +
                    "Verify that it is updated to the latest version and that the PODs are connected and on.");
                }
            }
        }

        private IEnumerator SetGameMode()
        {
            //Check the Game Mode to see if it is already set to "Gamepad"
            string coroutineUrl = "http://localhost:8085/gamemode";
            string GameModeGetResponse = "-1";
            yield return StartCoroutine(OmniConnectWebRequest.CoroutineGetRequest(coroutineUrl, value => GameModeGetResponse = value));

            //Set Game mode to "Gamepad" if it is not already.
            if (!GameModeGetResponse.Contains("Gamepad") && GameModeGetResponse != "Error")
            {
                OmniConnectMode omniConnectMode = new OmniConnectMode
                {
                    Data = "Gamepad"
                };
                string json = JsonUtility.ToJson(omniConnectMode);
                byte[] pData = Encoding.ASCII.GetBytes(json.ToCharArray());
                string webPostResponse = "-1";
                yield return StartCoroutine(OmniConnectWebRequest.CoroutinePostRequest(coroutineUrl, pData, value => webPostResponse = value));
            }
        }

        public SecureAuthenticationProtocolState GetSAPStatus()
        {
            return mySAPStatus;
        }

        /// <summary>
        ///     Gets the Authentication depending on version needed.
        /// </summary>
        /// <param name="result"></param>
        /// <returns></returns>
        private IEnumerator GetSecureAuthentication(Action<SecureAuthenticationProtocolState> result)
        {
            string versionCheckUrl = "http://localhost:8085/version";
            string versionWebResponse = "-1";
            yield return StartCoroutine(OmniConnectWebRequest.CoroutineGetRequest(versionCheckUrl, value => versionWebResponse = value));

            string v1 = versionWebResponse[23].ToString() + versionWebResponse[24].ToString() + versionWebResponse[25].ToString() + versionWebResponse[26].ToString() + versionWebResponse[27].ToString() + versionWebResponse[28].ToString() + versionWebResponse[29].ToString();
            string v2 = "1.3.4.0";
            var version1 = new Version(v1);
            var version2 = new Version(v2);
            int versionComparisonResult = version1.CompareTo(version2);

            if (versionComparisonResult >= 0)
            {
                //If 1.3.4.0 or newer, use the new healthcheck endpoint.
                string healthCheckUrl = "http://localhost:8085/healthcheck";
                string SACWebResponse = "-1";
                yield return StartCoroutine(OmniConnectWebRequest.CoroutineGetRequest(healthCheckUrl, value => SACWebResponse = value));

                if (SACWebResponse != "Error")
                {
                    switch (SACWebResponse[10])
                    {
                        case 'B':
                            Debug.Log("Secure Authentication Protocol Enabled");
                            result(SecureAuthenticationProtocolState.SAPEnabled);
                            break;
                        case 'U':
                            Debug.Log("Secure Authentication Protocol Disabled");
                            result(SecureAuthenticationProtocolState.SAPDisabled);
                            break;
                        case '-':
                            Debug.Log("Omni Not Connected: Please Connect Omni");
                            result(SecureAuthenticationProtocolState.SAPError);
                            break;
                        default:
                            Debug.Log("Secure Authentication Protocol check failed. Returned Default.");
                            result(SecureAuthenticationProtocolState.SAPError);
                            break;
                    }
                }
            }

            else if (versionComparisonResult < 0)
            {
                //If older than 1.3.4.0, use the old methods.
                string systemReadyCheckUrl = "http://localhost:8085/systemReady";
                string systemReadyWebResponse = "-1";
                yield return StartCoroutine(OmniConnectWebRequest.CoroutineGetRequest(systemReadyCheckUrl, value => systemReadyWebResponse = value));

                if (systemReadyWebResponse.Contains("OK;Unsecure"))
                {
                    result(SecureAuthenticationProtocolState.SAPDisabled);
                }
                else if (systemReadyWebResponse.Contains("OK;Secure"))
                {
                    result(SecureAuthenticationProtocolState.SAPEnabled);
                }
                else
                {
                    result(SecureAuthenticationProtocolState.SAPError);
                }
            }
        }
    }
}