#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <vector>
#include <stdint.h>

#include <windows.h>

#include "XCEngine/RHI/OpenGL/OpenGLDevice.h"
#include "XCEngine/RHI/OpenGL/OpenGLSwapChain.h"
#include "XCEngine/RHI/OpenGL/OpenGLCommandList.h"
#include "XCEngine/RHI/OpenGL/OpenGLBuffer.h"
#include "XCEngine/RHI/OpenGL/OpenGLVertexArray.h"
#include "XCEngine/RHI/OpenGL/OpenGLShader.h"
#include "XCEngine/RHI/OpenGL/OpenGLPipelineState.h"
#include "XCEngine/RHI/OpenGL/OpenGLTexture.h"
#include "XCEngine/RHI/OpenGL/OpenGLSampler.h"
#include "XCEngine/RHI/OpenGL/OpenGLScreenshot.h"
#include "XCEngine/Debug/Logger.h"
#include "XCEngine/Debug/ConsoleLogSink.h"
#include "XCEngine/Debug/RenderDocCapture.h"
#include "XCEngine/Core/Containers/String.h"

#pragma comment(lib, "opengl32.lib")

#include <GL/gl.h>

using namespace XCEngine::RHI;
using namespace XCEngine::Debug;
using namespace XCEngine::Containers;

static const int gWidth = 1280;
static const int gHeight = 720;

void Log(const char* format, ...) {
    char buffer[1024];
    va_list args;
    va_start(args, format);
    vsnprintf(buffer, sizeof(buffer), format, args);
    va_end(args);
    Logger::Get().Debug(LogCategory::Rendering, String(buffer));
}

LRESULT CALLBACK WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
    switch (msg) {
    case WM_CLOSE:
        PostQuitMessage(0);
        break;
    }
    return DefWindowProc(hwnd, msg, wParam, lParam);
}

void IdentityMatrix(float* m) {
    memset(m, 0, 16 * sizeof(float));
    m[0] = m[5] = m[10] = m[15] = 1.0f;
}

void TranslationMatrix(float* m, float x, float y, float z) {
    memset(m, 0, 16 * sizeof(float));
    m[0] = 1.0f; m[12] = x;
    m[5] = 1.0f; m[13] = y;
    m[10] = 1.0f; m[14] = z;
    m[15] = 1.0f;
}

void PerspectiveMatrix(float* m, float fov, float aspect, float nearZ, float farZ) {
    memset(m, 0, 16 * sizeof(float));
    float tanHalfFov = tanf(fov / 2.0f);
    m[0] = 1.0f / (aspect * tanHalfFov);  // m[0][0]
    m[5] = 1.0f / tanHalfFov;              // m[1][1]
    m[10] = -(farZ + nearZ) / (farZ - nearZ);  // m[2][2]
    m[14] = -(2.0f * farZ * nearZ) / (farZ - nearZ);  // m[2][3]
    m[15] = 0.0f;
    m[11] = -1.0f;  // m[3][2] = -1 for OpenGL clip space
}

struct Vertex {
    float pos[4];
    float texcoord[2];
};

void GenerateSphere(std::vector<Vertex>& vertices, std::vector<uint32_t>& indices, float radius, int segments) {
    vertices.clear();
    indices.clear();

    segments = (segments < 3) ? 3 : segments;

    for (int lat = 0; lat <= segments; ++lat) {
        float phi = static_cast<float>(3.14159265f) * lat / segments;
        float sinPhi = sinf(phi);
        float cosPhi = cosf(phi);

        for (int lon = 0; lon <= segments; ++lon) {
            float theta = static_cast<float>(2 * 3.14159265f) * lon / segments;
            float sinTheta = sinf(theta);
            float cosTheta = cosf(theta);

            Vertex v;
            v.pos[0] = radius * sinPhi * cosTheta;
            v.pos[1] = radius * cosPhi;
            v.pos[2] = radius * sinPhi * sinTheta;
            v.pos[3] = 1.0f;

            v.texcoord[0] = static_cast<float>(lon) / segments;
            v.texcoord[1] = static_cast<float>(lat) / segments;

            vertices.push_back(v);
        }
    }

    for (int lat = 0; lat < segments; ++lat) {
        for (int lon = 0; lon < segments; ++lon) {
            uint32_t topLeft = lat * (segments + 1) + lon;
            uint32_t topRight = topLeft + 1;
            uint32_t bottomLeft = (lat + 1) * (segments + 1) + lon;
            uint32_t bottomRight = bottomLeft + 1;

            indices.push_back(topLeft);
            indices.push_back(bottomLeft);
            indices.push_back(topRight);

            indices.push_back(topRight);
            indices.push_back(bottomLeft);
            indices.push_back(bottomRight);
        }
    }
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd) {
    Logger::Get().Initialize();
    Logger::Get().AddSink(std::make_unique<ConsoleLogSink>());
    Logger::Get().SetMinimumLevel(LogLevel::Debug);

    Log("[INFO] OpenGL Sphere Test Starting");

    WNDCLASSEXW wc = {};
    wc.cbSize = sizeof(WNDCLASSEXW);
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = WindowProc;
    wc.hInstance = hInstance;
    wc.lpszClassName = L"XCEngine_OpenGL_Sphere";

    if (!RegisterClassExW(&wc)) {
        Log("[ERROR] Failed to register window class");
        return -1;
    }

    RECT rect = { 0, 0, gWidth, gHeight };
    AdjustWindowRect(&rect, WS_OVERLAPPEDWINDOW, FALSE);

    HWND hwnd = CreateWindowExW(
        0,
        L"XCEngine_OpenGL_Sphere",
        L"OpenGL Sphere Test",
        WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, CW_USEDEFAULT,
        rect.right - rect.left, rect.bottom - rect.top,
        NULL, NULL, hInstance, NULL
    );

    if (!hwnd) {
        Log("[ERROR] Failed to create window");
        return -1;
    }

    RenderDocCapture::Get().Initialize(nullptr, hwnd);
    RenderDocCapture::Get().SetCaptureFilePath(".\\sphere_frame30");

    OpenGLDevice device;
    if (!device.InitializeWithExistingWindow(hwnd)) {
        Log("[ERROR] Failed to initialize OpenGL device");
        return -1;
    }

    RenderDocCapture::Get().SetDevice(device.GetNativeContext());

    ShowWindow(hwnd, nShowCmd);
    UpdateWindow(hwnd);

    Log("[INFO] OpenGL Device: %S", device.GetDeviceInfo().renderer.c_str());
    Log("[INFO] OpenGL Version: %S", device.GetDeviceInfo().version.c_str());

    OpenGLSwapChain swapChain;
    swapChain.Initialize(&device, hwnd, gWidth, gHeight);

    OpenGLCommandList commandList;

    std::vector<Vertex> vertices;
    std::vector<uint32_t> indices;
    GenerateSphere(vertices, indices, 1.0f, 32);
    Log("[INFO] Generated %d vertices, %d indices", (int)vertices.size(), (int)indices.size());

    OpenGLBuffer vertexBuffer;
    if (!vertexBuffer.InitializeVertexBuffer(vertices.data(), (uint32_t)(sizeof(Vertex) * vertices.size()))) {
        Log("[ERROR] Failed to initialize vertex buffer");
        return -1;
    }
    vertexBuffer.SetStride(sizeof(Vertex));

    OpenGLBuffer indexBuffer;
    if (!indexBuffer.InitializeIndexBuffer(indices.data(), (uint32_t)(sizeof(uint32_t) * indices.size()))) {
        Log("[ERROR] Failed to initialize index buffer");
        return -1;
    }

    OpenGLVertexArray vertexArray;
    vertexArray.Initialize();

    VertexAttribute posAttr = {};
    posAttr.index = 0;
    posAttr.count = 4;
    posAttr.type = VertexAttributeType::Float;
    posAttr.normalized = VertexAttributeNormalized::False;
    posAttr.stride = sizeof(Vertex);
    posAttr.offset = 0;
    vertexArray.AddVertexBuffer(vertexBuffer.GetID(), posAttr);

    VertexAttribute texAttr = {};
    texAttr.index = 1;
    texAttr.count = 2;
    texAttr.type = VertexAttributeType::Float;
    texAttr.normalized = VertexAttributeNormalized::False;
    texAttr.stride = sizeof(Vertex);
    texAttr.offset = sizeof(float) * 4;
    vertexArray.AddVertexBuffer(vertexBuffer.GetID(), texAttr);

    vertexArray.SetIndexBuffer(indexBuffer.GetID(), 0);

    OpenGLShader shader;
    if (!shader.CompileFromFile("Res/Shader/sphere.vert", "Res/Shader/sphere.frag")) {
        Log("[ERROR] Failed to compile shaders");
        return -1;
    }
    Log("[INFO] Shaders compiled successfully");

    float modelMatrix[16];
    float viewMatrix[16];
    float projectionMatrix[16];

    IdentityMatrix(viewMatrix);
    TranslationMatrix(modelMatrix, 0.0f, 0.0f, -5.0f);
    float aspect = 1280.0f / 720.0f;
    PerspectiveMatrix(projectionMatrix, 45.0f * 3.14159265f / 180.0f, aspect, 0.1f, 1000.0f);

    Log("[DEBUG] ProjectionMatrix:");
    for (int i = 0; i < 4; i++) {
        Log("[DEBUG]   row%d: %.4f %.4f %.4f %.4f", i, 
            projectionMatrix[i*4], projectionMatrix[i*4+1], projectionMatrix[i*4+2], projectionMatrix[i*4+3]);
    }
    Log("[DEBUG] ModelMatrix:");
    for (int i = 0; i < 4; i++) {
        Log("[DEBUG]   row%d: %.4f %.4f %.4f %.4f", i,
            modelMatrix[i*4], modelMatrix[i*4+1], modelMatrix[i*4+2], modelMatrix[i*4+3]);
    }

    OpenGLPipelineState pipelineState;
    OpenGLRasterizerState rasterizerState;
    rasterizerState.cullFaceEnable = false;
    pipelineState.SetRasterizerState(rasterizerState);

    OpenGLDepthStencilState depthStencilState;
    depthStencilState.depthTestEnable = true;
    depthStencilState.depthWriteEnable = true;
    depthStencilState.depthFunc = ComparisonFunc::Less;
    pipelineState.SetDepthStencilState(depthStencilState);

    ViewportState viewportState = { 0.0f, 0.0f, (float)gWidth, (float)gHeight, 0.0f, 1.0f };
    pipelineState.SetViewport(viewportState);

    pipelineState.AttachShader(shader.GetID());
    pipelineState.Apply();

    Log("[DEBUG] Shader program ID: %u", shader.GetID());
    int modelLoc = shader.GetUniformLocation("gModelMatrix");
    int viewLoc = shader.GetUniformLocation("gViewMatrix");
    int projLoc = shader.GetUniformLocation("gProjectionMatrix");
    Log("[DEBUG] Uniform locations - gModelMatrix: %d, gViewMatrix: %d, gProjectionMatrix: %d", modelLoc, viewLoc, projLoc);
    commandList.SetShader(&shader);
    commandList.SetUniformMat4("gModelMatrix", modelMatrix);
    commandList.SetUniformMat4("gViewMatrix", viewMatrix);
    commandList.SetUniformMat4("gProjectionMatrix", projectionMatrix);
    commandList.SetUniformInt("uTexture", 0);

    OpenGLTexture texture;
    if (!texture.LoadFromFile("Res/Image/earth.png", true)) {
        Log("[ERROR] Failed to load texture");
        return -1;
    }
    Log("[INFO] Texture loaded successfully");

    OpenGLSampler sampler;
    OpenGLSamplerDesc samplerDesc = {};
    samplerDesc.minFilter = SamplerFilter::Linear;
    samplerDesc.magFilter = SamplerFilter::Linear;
    samplerDesc.wrapS = SamplerWrapMode::ClampToEdge;
    samplerDesc.wrapT = SamplerWrapMode::ClampToEdge;
    sampler.Initialize(samplerDesc);

    MSG msg = {};
    int frameCount = 0;
    const int captureStartFrame = 29;
    const int captureEndFrame = 30;

    int renderCount = 0;
    while (true) {
        if (PeekMessageW(&msg, NULL, 0, 0, PM_REMOVE)) {
            if (msg.message == WM_QUIT) {
                break;
            }
            TranslateMessage(&msg);
            DispatchMessageW(&msg);
        } else {
            device.MakeContextCurrent();

            renderCount++;
            GLenum err = glGetError();
            if (err != GL_NO_ERROR) Log("[DEBUG] GL error before clear: 0x%x", err);

            commandList.SetViewport(0, 0, gWidth, gHeight);
            commandList.Clear(0.0f, 0.0f, 1.0f, 1.0f, 1 | 2);  // COLOR_BUFFER | DEPTH_BUFFER

            err = glGetError();
            if (err != GL_NO_ERROR) Log("[DEBUG] GL error after clear: 0x%x", err);

            pipelineState.Bind();

            err = glGetError();
            if (err != GL_NO_ERROR) Log("[DEBUG] GL error after pipeline bind: 0x%x", err);

            indexBuffer.Bind();
            vertexArray.Bind();

            texture.Bind(0);
            sampler.Bind(0);

            err = glGetError();
            if (err != GL_NO_ERROR) Log("[DEBUG] GL error before draw: 0x%x", err);

            commandList.DrawIndexed(PrimitiveType::Triangles, (uint32_t)indices.size(), 0, 0);

            swapChain.Present(0, 0);
            frameCount++;

            if (frameCount >= captureEndFrame) {
                RenderDocCapture::Get().EndCapture();
                Log("[INFO] RenderDoc capture ended at frame %d", frameCount);
                break;
            }

            if (frameCount == captureStartFrame) {
                RenderDocCapture::Get().BeginCapture("OpenGL_Sphere_Test");
                Log("[INFO] RenderDoc capture started at frame %d", frameCount);
            }
        }
    }

    Log("[INFO] Rendered %d frames (capture was %d-%d)", renderCount, captureStartFrame, captureEndFrame);
    Log("[INFO] Capture complete - taking screenshot!");

    char exePath[MAX_PATH];
    GetModuleFileNameA(NULL, exePath, MAX_PATH);
    char* lastSlash = strrchr(exePath, '\\');
    if (lastSlash) *lastSlash = '\0';
    strcat_s(exePath, "\\sphere.ppm");
    OpenGLScreenshot::Capture(device, swapChain, exePath);

    sampler.Shutdown();
    texture.Shutdown();
    indexBuffer.Shutdown();
    vertexArray.Shutdown();
    vertexBuffer.Shutdown();
    shader.Shutdown();
    pipelineState.Shutdown();

    swapChain.Shutdown();
    device.Shutdown();

    RenderDocCapture::Get().Shutdown();
    Logger::Get().Shutdown();

    Log("[INFO] OpenGL Sphere Test Finished");
    return 0;
}