using BepInEx;
using BepInEx.Configuration;
using System;
using UnityEngine;

namespace UniformAim
{
    [BepInPlugin("com.greg.tarkovuniformaim", "Uniform Aim for Tarkov", "1.0.0")]
    [BepInProcess("EscapeFromTarkov.exe")]

    public class Plugin : BaseUnityPlugin
    {
        //Bepinex.Configurator fields
        public static ConfigEntry<int> configFOV;
        public static ConfigEntry<int> configCoeff;
        public static ConfigEntry<int> configSens;
        public static ConfigEntry<bool> configUseHFOV;

        //TODO: figure out a way to read game settings to default the configFOV.Value to whatever the player has already set
        //TODO: figure out a way to read game settings to apply configSens.Value as a multiplier on top of Tarkov's stock sensitivity setting

        public static float mySens = 1f;
        public static float aimingSens;

        //sight data for hacky workarounds
        public static int SelectedScope = 0;
        public static int SelectedScopeMode = 0;
        public static bool isAiming = false;

        //human-friendly names for variables used later
        float FPSCameraFOV;
        float ScopeFOV;
        float currentFOV;

        //values to prevent unnecessary repetition
        float cachedFOV;
        string cachedDebugInfo;

        //aspect ratio for further calculations
        float GetAspectRatio()
        {
            return Camera.allCameras[0].aspect;
        }
        //calculate horizontal FOV based on vertical FOV, currently unused but could be useful in the future
        float CalculateHFOV(float FOV)
        {
            float vFOVRad = FOV / 2 * Mathf.Deg2Rad;
            float hFOVRad = (float)(2 * Math.Atan(GetAspectRatio() * Math.Tan(vFOVRad)));

            return (float)(hFOVRad * Mathf.Rad2Deg);
        }
        //calculate sensitivity based on FOV difference and the coefficient
        float CalculateSensitivity(float aimedFOV, float hipFOV)
        {
            //clamp to avoid invalid values
            aimedFOV = Mathf.Clamp(aimedFOV, 1f, 75f) * Mathf.Deg2Rad;
            hipFOV = Mathf.Clamp(hipFOV, 1f, 75f) * Mathf.Deg2Rad;

            //check if configUseHFOV is enabled, convert to horizontal degrees if true
            if (configUseHFOV.Value)
            {
                aimedFOV = CalculateHFOV(aimedFOV);
                hipFOV = CalculateHFOV(hipFOV);
            }

            float exponent = (float)(100f / configCoeff.Value);

            float tanRatio = (float)(Math.Tan(aimedFOV / 2) / Math.Tan(hipFOV / 2));

            float sensitivity = configSens.Value / 100f;

            float result = (float)Math.Pow(tanRatio, exponent) * sensitivity;

            return result;
        }

        //determine if the player is looking through the scope
        bool isScopeCameraActive()
        {
            if (Camera.allCamerasCount > 1) { return Camera.allCameras[1].GetComponent<Behaviour>().isActiveAndEnabled; }
            return false;
        }

        //determine the correct FOV for calculations
        void DetermineCurrentFOV()
        {
            if (SelectedScope == 0 && isScopeCameraActive()) { currentFOV = ScopeFOV; } else { currentFOV = FPSCameraFOV; }

            //dirty fix for the Ultima MP-155 shotgun
            if (FPSCameraFOV > 35 && isScopeCameraActive() && ScopeFOV == 15) { currentFOV = FPSCameraFOV; }
        }

        void Awake()
        {
            new UpdateSensitivityPatch().Enable();
            new get_AimingSensitivityPatch().Enable();
            new get_SelectedScopeIndexPatch().Enable();
            new get_SelectedScopeModePatch().Enable();
            new get_IsAimingPatch().Enable();

            //add configuration slider for field of view
            configFOV = Config.Bind("General", "FOV", 75, new ConfigDescription("In-game Field of View value", new AcceptableValueRange<int>(51, 75)));

            //add coefficient slider
            configCoeff = Config.Bind("General", "Coefficient", 133, new ConfigDescription("Coefficient - increases sensitivity at higher zoom levels", new AcceptableValueRange<int>(1, 300)));

            //add sensitivity slider
            configSens = Config.Bind("General", "Sensitivity", 25, new ConfigDescription("Sensitivity while aiming", new AcceptableValueRange<int>(1, 200)));

            //use HFOV instead of VFOV for sensitivity calculations
            configUseHFOV = Config.Bind("General", "Use Horizontal FOV?", true, new ConfigDescription("Toggles between using Horizontal FOV and Vertical FOV for sensitivity calculations."));
        }

        void FixedUpdate()
        {
            //FixedUpdate() at 50Hz (Unity default) tickrate appears to resolve the issue of this script breaking when AI spawns.
            Time.fixedDeltaTime = (1f / 50f);

            if (isAiming)
            {
                //Grab FOV values for calculation
                FPSCameraFOV = Camera.allCameras[0].fieldOfView; //Camera[0] tends to be FPS Camera
                if (Camera.allCamerasCount > 1) { ScopeFOV = Camera.allCameras[1].fieldOfView; } //Camera[1] tends to be BaseOpticCamera

                //Figure out if the FPSCamera is zoomed in, prevents the script from ticking while the player is healing
                if (FPSCameraFOV < configFOV.Value)
                {
                    DetermineCurrentFOV();
                    //do not update sensitivity if currentFOV hasn't changed
                    if (cachedFOV != currentFOV) { mySens = CalculateSensitivity(currentFOV, configFOV.Value); cachedFOV = currentFOV; }
                }
            }
        }
    }
}