using System.Reflection;
using System.Runtime.Loader;
using System.Runtime.InteropServices;

using ImGuiNET;
using SharpPluginLoader.Core;
using SharpPluginLoader.Core.Memory;

namespace WorldTuningTool
{
    public unsafe class Plugin : IPlugin
    {
        public string Name => "World Tuning Tool";
        public string Author => "Akon City Software";

        // @TODO:
        //  - Port FXAA object.
        //  - Port some stuff as is.
        //  - OnAreaChange.
        //  - Shadow distance retuning.
        //  - Work out obvious simplifications.
        //  - sMhRenderer vs common parameter address.
        //  - Overrides system.
        //  - Pass on LODs.
        //  - Verbose descriptions.
        //  - Re-implement shadow res override for hoarfrost.
        //  - Exact float flag for hex input?

        private bool dofDisabled = false;
        private Patch jmpOverDof;

        public void SetDofForceOff(bool off)
        {
            if (off && !dofDisabled)
            {
                jmpOverDof.Enable();
            }
            else if (!off && dofDisabled)
            {
                jmpOverDof.Disable();
            }
            dofDisabled = off;
        }

        public bool GetDofDisabled()
        {
            return dofDisabled;
        }

        /*
        public PluginData Initialize()
        {
            PluginData data = new PluginData();
            data.ExportedFunctions.Add(("SetDofForceOff", SetDofForceOff));
            data.ExportedFunctions.Add(("GetDofDisabled", GetDofDisabled));
            return data;
        }
        */

        public void OnPreMain()
        {
            unchecked
            {
                jmpOverDof = new Patch((nint)0x1424233C6, [0xEB]); // je -> jmp.
            }
        }

        private static bool replaceShaderFromFile(ShaderInfo *info, string path)
        {
            if (!System.IO.File.Exists(path))
            {
                Log.Warn($"File not found: {path}.");
                return false;
            }
            byte[] shaderData;
            try
            {
                shaderData = System.IO.File.ReadAllBytes(path);
            }
            catch (Exception)
            {
                Log.Error($"Failed to read: {path}.");
                return false;
            }
            info->Replacement.Length = shaderData.Length;
            info->Replacement.Source = (byte *)Marshal.UnsafeAddrOfPinnedArrayElement<byte>(shaderData, 0);
            return true;
        }

        private string shaderPath = "nativePC/plugins/CSharp/Shaders";
        private bool shadersLoadedOnce = false;
        public unsafe void OnCreateShader(ShaderInfo *info)
        {
            string hash = new string(info->DxbcHash);
            if (!shadersLoadedOnce && hash == "2e4e18fd-6ea5eeae-2de3d65c-26ab36dd")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/volume_upsample.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("Volume upsample shader 1 replaced.");
                }
            }
            else if (!shadersLoadedOnce && hash == "e2c8c13e-45bc99b2-4c3d7699-3d66188e")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/volume_upsample2.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("Volume upsample shader 2 replaced.");
                }
                // This allows us to A/B using the volume rendering value 2 switch.
                shadersLoadedOnce = true;
            }
            else if (hash == "8cf2a107-ecde214b-9939b350-7b2af1a7")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/cube_only.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("Cube Only shader replaced.");
                }
            }
            else if (hash == "b21dd223-98ab56ae-918264e6-eb6e8ee4")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/sslr.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("SSLR shader replaced.");
                }
            }
            else if (hash == "9ff245fb-4fd555e0-04d0ef15-84609fe1")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/fxaa_max_quality.hlsl")) {
                    info->Replacement.Type = ShaderSourceType.HLSL;
                    Log.Info("FXAA shader replaced.");
                }
            }
            else if (hash == "2eed1f00-e24d1b19-9d521064-17b9a586")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/body_skin.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("Body skin shader replaced.");
                }
            }
            else if (hash == "8e5e3c09-ebe77ee4-ba1cb659-d25bc7bf")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/face.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("Face shader replaced.");
                }
            }
            /*
            else if (hash == "d7e47ffe-82572c64-795c4698-341e5b91")
            {
                if (replaceShaderFromFile(info, $"{shaderPath}/sslr_mips.shdr")) {
                    info->Replacement.Type = ShaderSourceType.BINARY;
                    Log.Info("SSLR mips shader replaced.");
                }
            }
            */
        }

        public void OnLoad()
        {
        }

        public void OnImGuiRender()
        {
            if (ImGui.Checkbox("Disable Depth of Field", ref dofDisabled))
            {
                if (dofDisabled)
                {
                    jmpOverDof.Enable();
                }
                else
                {
                    jmpOverDof.Disable();
                }
            }
        }
    }
}