#include "main.h"

#include <Core/Application/ApplicationManager.h>
#include <Core/Common/EnumUtils.h>
#include <Core/Common/String.h>
#include <Core/HAL/Display/Display.h>
#include <Core/HAL/Event/SystemEvent.h>
#include <Core/HAL/Filesystem/Filesystem.h>
#include <Core/JulietInit.h>
#include <Core/Logging/LogManager.h>
#include <Core/Logging/LogTypes.h>
#include <Core/Main.h>
#include <Core/Math/Matrix.h>
#include <Core/Memory/MemoryArena.h>
#include <Core/Memory/Utils.h>
#include <cstdlib>
#include <Engine/Debug/MemoryDebugger.h>
#include <Graphics/Camera.h>
#include <Graphics/DebugDisplay.h>
#include <Graphics/Graphics.h>
#include <Graphics/GraphicsConfig.h>
#include <Graphics/GraphicsPipeline.h>
#include <Graphics/Mesh.h>
#include <Graphics/MeshRenderer.h>
#include <Graphics/RenderPass.h>
#include <Graphics/VertexData.h>
#include <Juliet.h>

#ifdef JULIET_ENABLE_IMGUI
#include <imgui.h>
#endif

static bool ShowMemoryDebugger = false;

// TODO : Replace with message box from framework + call main and not winmain + subsystem
// TODO : Think how to do the draw pipeline.
// Ex: Expose a Draw method ?
// Store a graphics context ?
// For now. Put everything in Update down below.
// Should split update from draw, update should have a != timestep than graphics (60fps or more)

// TODO : Remove main.h. Useless
// May be remove that Application class, useless too.

using namespace Juliet;

extern "C" {
__declspec(dllexport) extern const unsigned int D3D12SDKVersion = 615;
}
extern "C" {
__declspec(dllexport) extern const char* D3D12SDKPath = ".\\";
}

namespace
{
    using GameInit_t     = void (*)(GameInitParams*);
    using GameShutdown_t = void (*)(void);
    using GameUpdate_t   = void (*)(float deltaTime);
    struct GameFunctionTable
    {
        GameInit_t     Init     = nullptr;
        GameShutdown_t Shutdown = nullptr;
        GameUpdate_t   Update   = nullptr;
    } Game;

    const char* GameFunctionTable[] = { "GameInit", "GameShutdown", "GameUpdate" };

    Arena* PlatformArena = nullptr;
} // namespace

void JulietApplication::Init()
{
    Log(LogLevel::Message, LogCategory::Tool, "Initializing Juliet Application...");

    Log(LogLevel::Message, LogCategory::Tool, "%s", CStr(GetBasePath()));

    PlatformArena = ArenaAllocate({ .AllowRealloc = true } JULIET_DEBUG_PARAM("Platform Arena"));

    GraphicsConfig config;
#if JULIET_DEBUG
    config.EnableDebug = true;
#endif
    GraphicsDevice = CreateGraphicsDevice(config);

    MainWindow = CreatePlatformWindow("Juliet Editor", 1280, 720);

    Running = MainWindow != nullptr && GraphicsDevice != nullptr;

    if (Running)
    {
        AttachToWindow(GraphicsDevice, MainWindow);
        {
            Running = InitializeMeshRenderer(PlatformArena, GraphicsDevice, MainWindow);

            // Create Depth Buffer
            TextureCreateInfo depthCI = {};
            depthCI.Type              = TextureType::Texture_2D;
            depthCI.Width             = 1280;
            depthCI.Height            = 720;
            depthCI.Format            = TextureFormat::D32_FLOAT;
            depthCI.Flags             = TextureUsageFlag::DepthStencilTarget;
            depthCI.LayerCount        = 1;
            depthCI.MipLevelCount     = 1;
            depthCI.SampleCount       = TextureSampleCount::One;
            DepthBuffer               = CreateTexture(GraphicsDevice, depthCI);
            if (DepthBuffer == nullptr)
            {
                LogError(LogCategory::Game, "Failed to create depth buffer!");
                Running = false;
            }

            constexpr int   kGridSize = 10;
            constexpr float kSpacing  = 2.5f;
            constexpr float kOffset   = (kGridSize - 1) * kSpacing * 0.5f;

            for (int row = 0; row < kGridSize; ++row)
            {
                for (int col = 0; col < kGridSize; ++col)
                {
                    MeshID cube = AddCube();
                    float  x    = static_cast<float>(col) * kSpacing - kOffset;
                    float  y    = static_cast<float>(row) * kSpacing - kOffset;

                    float seed = static_cast<float>(row * kGridSize + col);
                    Matrix rotation = MatrixRotation(seed * 0.73f, seed * 1.17f, seed * 0.53f);
                    SetMeshTransform(cube, MatrixTranslation(x, y, 0.0f) * rotation);
                }
            }

            CommandList* loadCmd = AcquireCommandList(GraphicsDevice);
            LoadMeshesOnGPU(loadCmd);
            SubmitCommandLists(loadCmd);

            if (Running == false)
            {
                return;
            }
        }

        GameCode.Functions     = reinterpret_cast<void**>(&Game);
        GameCode.FunctionCount = ArraySize(GameFunctionTable);
        GameCode.FunctionNames = GameFunctionTable;
        InitHotReloadCode(GameCode, ConstString("Game.dll"), ConstString("Game_Temp.dll"), ConstString("lock.tmp"));
        if ((Running = GameCode.IsValid))
        {
            GameInitParams params;
            params.GameArena = GameArena = ArenaAllocate({} JULIET_DEBUG_ONLY(, "Game Arena"));
            params.ScratchArena = GameScratchArena = ArenaAllocate({} JULIET_DEBUG_ONLY(, "Scratch Arena"));
            Game.Init(&params);
        }
    }
}

void JulietApplication::Shutdown()
{
    Log(LogLevel::Message, LogCategory::Tool, "Shutting down Juliet Application...");

    if (GameCode.IsValid)
    {
        Game.Shutdown();
        ShutdownHotReloadCode(GameCode);
    }

    if (GraphicsPipeline)
    {
        DestroyGraphicsPipeline(GraphicsDevice, GraphicsPipeline);
    }

    if (DepthBuffer)
    {
        DestroyTexture(GraphicsDevice, DepthBuffer);
    }

    ShutdownMeshRenderer();

    if (MainWindow && GraphicsDevice)
    {
        DetachFromWindow(GraphicsDevice, MainWindow);
    }

    if (MainWindow)
    {
        DestroyPlatformWindow(MainWindow);
    }

    if (GraphicsDevice)
    {
        DestroyGraphicsDevice(GraphicsDevice);
    }

    ArenaRelease(PlatformArena);

    Log(LogLevel::Message, LogCategory::Tool, "Juliet App shutdown Completed");
}

void JulietApplication::Update()
{
    static LARGE_INTEGER frequency = {};
    static LARGE_INTEGER lastTime  = {};
    if (frequency.QuadPart == 0)
    {
        QueryPerformanceFrequency(&frequency);
        QueryPerformanceCounter(&lastTime);
    }

    LARGE_INTEGER currentTime;
    QueryPerformanceCounter(&currentTime);
    float deltaTime = static_cast<float>(currentTime.QuadPart - lastTime.QuadPart) / static_cast<float>(frequency.QuadPart);
    lastTime = currentTime;

    CameraTime += deltaTime;

    static float fpsTimer  = 0.0f;
    static int   fpsFrames = 0;
    fpsTimer += deltaTime;
    fpsFrames++;
    if (fpsTimer >= 0.5f)
    {
        float fps = static_cast<float>(fpsFrames) / fpsTimer;
        float ms  = (fpsTimer / static_cast<float>(fpsFrames)) * 1000.0f;
        char title[64];
        snprintf(title, sizeof(title), "Juliet | %.1f FPS | %.2f ms", static_cast<double>(fps), static_cast<double>(ms));
        SetWindowTitle(MainWindow, WrapString(title));
        fpsTimer  = 0.0f;
        fpsFrames = 0;
    }

    bool        reloadShaders         = false;
    static bool reloadShadersDebounce = false;

    SystemEvent evt;
    while (GetEvent(evt))
    {
        if (evt.Type == EventType::Window_Close_Request)
        {
            if (evt.Data.Window.AssociatedWindowID == GetWindowID(MainWindow))
            {
                Running = false;
            }
        }

        // Shader hot reload using keyboard.
        if (!reloadShadersDebounce && ((GetKeyModState() & KeyMod::Alt) != KeyMod::None) && IsKeyDown(ScanCode::R))
        {
            reloadShaders         = true;
            reloadShadersDebounce = true;
        }

        if (reloadShadersDebounce && !IsKeyDown(ScanCode::R))
        {
            reloadShadersDebounce = false;
        }
    }

#ifdef JULIET_ENABLE_IMGUI
    // ImGui::ShowDemoWindow();
#endif

    DebugDisplay_DrawLine({ 0.0f, 0.0f, 0.0f }, { 1.0f, 0.0f, 0.0f }, { 1.0f, 0.0f, 0.0f, 1.0f }, false);
    DebugDisplay_DrawLine({ 0.0f, 0.0f, 0.0f }, { 0.0f, 1.0f, 0.0f }, { 0.0f, 1.0f, 0.0f, 1.0f }, true);
    DebugDisplay_DrawLine({ 0.0f, 0.0f, 0.0f }, { 0.0f, 0.0f, 1.0f }, { 0.0f, 0.0f, 1.0f, 1.0f }, true);
    DebugDisplay_DrawSphere({ 0.0f, 0.0f, 0.0f }, 0.5f, { 1.0f, 1.0f, 0.0f, 1.0f }, true);

    Game.Update(0.0f);

    if (ShouldReloadCode(GameCode))
    {
        ReloadCode(GameCode);
    }

    if (reloadShaders)
    {
        WaitUntilGPUIsIdle(GraphicsDevice);

#if ALLOW_SHADER_HOT_RELOAD
        ReloadMeshRendererShaders();
#endif
    }

    // Memory debugger toggle
    static bool toggleDebounce = false;
    if (IsKeyDown(Juliet::ScanCode::Home))
    {
        if (!toggleDebounce)
        {
            ShowMemoryDebugger = !ShowMemoryDebugger;
            toggleDebounce     = true;
        }
    }
    else
    {
        toggleDebounce = false;
    }

    // Auto-close logic
    if (AutoCloseFrameCount > 0)
    {
        AutoCloseFrameCount--;
        if (AutoCloseFrameCount == 0)
        {
            Log(LogLevel::Message, LogCategory::Tool, "Auto-closing application as requested.");
            Running = false;
        }
    }

    if (ShowMemoryDebugger)
    {
#if JULIET_DEBUG
        Debug::DebugDrawMemoryArena();
#endif
    }

    ArenaClear(GameScratchArena);
}

void JulietApplication::OnPreRender(CommandList* /*cmd*/) {}

void JulietApplication::OnRender(RenderPass* pass, CommandList* cmd)
{
    PushData pushData       = {};
    pushData.ViewProjection = Camera_GetViewProjectionMatrix(GetDebugCamera());

    RenderMeshes(pass, cmd, pushData);
}

ColorTargetInfo JulietApplication::GetColorTargetInfo(Texture* swapchainTexture)
{
    ColorTargetInfo info = {};
    info.TargetTexture   = swapchainTexture;
    info.ClearColor      = { .R = 0.0f, .G = 0.0f, .B = 0.0f, .A = 1.0f };
    info.LoadOperation   = LoadOperation::Clear;
    info.StoreOperation  = StoreOperation::Store;
    return info;
}

DepthStencilTargetInfo* JulietApplication::GetDepthTargetInfo()
{
    static DepthStencilTargetInfo info = {};
    info.TargetTexture                 = DepthBuffer;
    info.ClearDepth                    = 1.0f;
    info.LoadOperation                 = LoadOperation::Clear;
    info.StoreOperation                = StoreOperation::Store;
    return &info;
}

Camera JulietApplication::GetDebugCamera()
{
    float time = CameraTime;

    float orbitSpeed       = 0.5f;
    float currentOrbitTime = time * orbitSpeed;

    // --- Adjusted for 1-Meter Scale ---
    float baseRadius = 25.0f; // Increased to see 10x10 cube grid

    float radius = baseRadius;
    //* Uncomment for active zoom
    float zoomAmplitude = 15.0f;
    float zoomSpeed     = 0.5f;
    radius              = baseRadius + (sinf(time * zoomSpeed) * zoomAmplitude);
    //*/
    float zHeight = radius * 0.5f; // Keep a nice downward viewing angle

    Camera cam      = {};
    cam.Position    = { cosf(currentOrbitTime) * radius, sinf(currentOrbitTime) * radius, zHeight };
    cam.Target      = { 0.0f, 0.0f, 0.0f };
    cam.Up          = { 0.0f, 0.0f, 1.0f };
    cam.FOV         = 1.047f;
    cam.AspectRatio = 1200.0f / 800.0f;
    cam.NearPlane   = 0.1f;
    cam.FarPlane    = 1000.0f;

    return cam;
}

bool JulietApplication::IsRunning()
{
    return Running;
}
namespace
{
    JulietApplication EditorApplication;
}

JulietApplication& GetEditorApplication()
{
    return EditorApplication;
}

int JulietMain(int argc, wchar_t** argv)
{
    if (argc > 1)
    {
        for (int i = 1; i < argc; ++i)
        {
            if (wcscmp(argv[i], L"-autoclose") == 0 && (i + 1 < argc))
            {
                int frames = _wtoi(argv[i + 1]);
                EditorApplication.SetAutoCloseFrameCount(frames);
            }
        }
    }

    StartApplication(EditorApplication, JulietInit_Flags::Display);

    // Pause here to not close the console window immediatly on stop
    // Only pause if not in auto-close mode
    if (EditorApplication.GetAutoCloseFrameCount() == -1 && !Debug::IsDebuggerPresent())
    {
        system("PAUSE");
    }

    return EXIT_SUCCESS;
}
