// D:\Dev\Mosis\MosisService\designer\main.cpp
// Mosis Designer - Desktop UI development tool with hot-reload

#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <RmlUi/Core.h>
#include <RmlUi/Lua.h>
#include <RmlUi/Debugger.h>
#include "RmlUi_Renderer_GL3.h"
#include "platform.h"
#include "desktop_platform.h"
#include "desktop_file_interface.h"
#include "hot_reload.h"
#include "testing/action_recorder.h"
#include "testing/action_player.h"
#include "testing/ui_inspector.h"
#include "testing/visual_capture.h"
#include <RmlUi/Lua/Interpreter.h>
#include <iostream>
#include <fstream>
#include <filesystem>
#include <memory>
#include <chrono>
#include <ctime>

namespace fs = std::filesystem;

// Global state
static GLFWwindow* g_window = nullptr;
static Rml::Context* g_context = nullptr;
static RenderInterface_GL3* g_render_interface = nullptr;
static mosis::DesktopPlatform* g_platform = nullptr;
static mosis::HotReload* g_hot_reload = nullptr;
static std::string g_current_document_path;
static std::string g_current_screen_url;  // For hierarchy dump - tracks current screen
static bool g_needs_reload = false;

// Resolution presets
static int g_width = 540;
static int g_height = 960;

// Test mode
enum class TestMode {
    Interactive,  // Normal interactive mode with hot-reload
    Record,       // Record user actions to JSON
    Playback,     // Playback actions from JSON
    Screenshot,   // Take a screenshot and exit
    DumpHierarchy // Dump UI hierarchy to JSON and exit
};

static TestMode g_test_mode = TestMode::Interactive;
static std::string g_test_input_path;   // Input file for playback
static std::string g_test_output_path;  // Output file for record/screenshot/hierarchy
static mosis::testing::ActionRecorder* g_action_recorder = nullptr;
static mosis::testing::ActionPlayer* g_action_player = nullptr;

// Logging and hierarchy dump for testing
static std::string g_log_file_path;       // Log file path (--log)
static std::string g_hierarchy_file_path; // Continuous hierarchy dump path (--hierarchy)
static std::ofstream g_log_file;

// Forward declarations
bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height);
void ShutdownRmlUi();
bool LoadDocument(const std::string& path);
void ReloadDocument();

// GLFW callbacks
static void ErrorCallback(int error, const char* description) {
    std::cerr << "GLFW Error " << error << ": " << description << std::endl;
}

static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods) {
    if (action != GLFW_PRESS) return;

    // F5 - Reload
    if (key == GLFW_KEY_F5) {
        g_needs_reload = true;
    }
    // F12 - Toggle debugger
    else if (key == GLFW_KEY_F12) {
        Rml::Debugger::SetVisible(!Rml::Debugger::IsVisible());
    }
    // Escape - Back navigation
    else if (key == GLFW_KEY_ESCAPE) {
        // Record back button action if recording
        if (g_action_recorder && g_action_recorder->IsRecording()) {
            g_action_recorder->RecordButton("back");
        }
        if (g_context) {
            g_context->ProcessKeyDown(Rml::Input::KI_ESCAPE, 0);
            g_context->ProcessKeyUp(Rml::Input::KI_ESCAPE, 0);
        }
    }
    // R - Toggle recording (in interactive mode)
    else if (key == GLFW_KEY_R && g_test_mode == TestMode::Interactive) {
        if (!g_action_recorder) {
            g_action_recorder = new mosis::testing::ActionRecorder(g_width, g_height);
        }

        if (g_action_recorder->IsRecording()) {
            g_action_recorder->StopRecording();
            // Generate filename with timestamp
            auto now = std::chrono::system_clock::now();
            auto time_t = std::chrono::system_clock::to_time_t(now);
            std::tm tm_buf;
            localtime_s(&tm_buf, &time_t);
            char buffer[64];
            std::strftime(buffer, sizeof(buffer), "recording_%Y%m%d_%H%M%S.json", &tm_buf);
            std::string filename = buffer;
            if (g_action_recorder->SaveToFile(filename)) {
                std::cout << "Recording saved to: " << filename << std::endl;
            } else {
                std::cerr << "Failed to save recording" << std::endl;
            }
        } else {
            g_action_recorder->StartRecording();
            std::cout << "Recording started. Press R again to stop." << std::endl;
        }
    }
}

static void MouseButtonCallback(GLFWwindow* window, int button, int action, int mods) {
    if (!g_context) return;

    double xpos, ypos;
    glfwGetCursorPos(window, &xpos, &ypos);

    // Convert from physical (GLFW) to logical (RmlUi) coordinates
    // GLFW reports physical pixels, but RmlUi context uses logical pixels
    float scaleX, scaleY;
    glfwGetWindowContentScale(window, &scaleX, &scaleY);
    int logicalX = static_cast<int>(xpos / scaleX);
    int logicalY = static_cast<int>(ypos / scaleY);

    // Debug log for click detection
    Rml::Log::Message(Rml::Log::LT_INFO, "Mouse %s at physical(%.0f, %.0f) logical(%d, %d) button=%d",
        action == GLFW_PRESS ? "down" : "up", xpos, ypos, logicalX, logicalY, button);

    int key_modifier = 0;
    if (mods & GLFW_MOD_CONTROL) key_modifier |= Rml::Input::KM_CTRL;
    if (mods & GLFW_MOD_SHIFT) key_modifier |= Rml::Input::KM_SHIFT;
    if (mods & GLFW_MOD_ALT) key_modifier |= Rml::Input::KM_ALT;

    // Update mouse position before processing button event (using logical coords)
    g_context->ProcessMouseMove(logicalX, logicalY, key_modifier);

    if (button == GLFW_MOUSE_BUTTON_LEFT) {
        if (action == GLFW_PRESS) {
            // Record mouse down in record mode (use logical coords)
            if (g_action_recorder && g_action_recorder->IsRecording()) {
                g_action_recorder->RecordMouseDown(logicalX, logicalY);
            }
            g_context->ProcessMouseButtonDown(0, key_modifier);
        } else if (action == GLFW_RELEASE) {
            // Record mouse up in record mode
            if (g_action_recorder && g_action_recorder->IsRecording()) {
                g_action_recorder->RecordMouseUp(logicalX, logicalY);
            }
            g_context->ProcessMouseButtonUp(0, key_modifier);
        }
    }
}

static void CursorPosCallback(GLFWwindow* window, double xpos, double ypos) {
    if (!g_context) return;

    // Convert from physical to logical coordinates
    float scaleX, scaleY;
    glfwGetWindowContentScale(window, &scaleX, &scaleY);
    int logicalX = static_cast<int>(xpos / scaleX);
    int logicalY = static_cast<int>(ypos / scaleY);

    g_context->ProcessMouseMove(logicalX, logicalY, 0);
}

static void ScrollCallback(GLFWwindow* window, double xoffset, double yoffset) {
    if (!g_context) return;
    g_context->ProcessMouseWheel(static_cast<float>(-yoffset), 0);
}

static void FramebufferSizeCallback(GLFWwindow* window, int width, int height) {
    // Update render interface viewport when framebuffer size changes (DPI scaling)
    if (g_render_interface) {
        g_render_interface->SetViewport(width, height);
        std::cout << "Framebuffer resized to: " << width << "x" << height << std::endl;
    }
}

// System interface for RmlUi
class DesktopSystemInterface : public Rml::SystemInterface {
public:
    double GetElapsedTime() override {
        return glfwGetTime();
    }

    bool LogMessage(Rml::Log::Type type, const Rml::String& message) override {
        const char* type_str = "";
        switch (type) {
            case Rml::Log::LT_ERROR:   type_str = "[ERROR]"; break;
            case Rml::Log::LT_WARNING: type_str = "[WARN]"; break;
            case Rml::Log::LT_INFO:    type_str = "[INFO]"; break;
            default: type_str = "[DEBUG]"; break;
        }
        std::cout << type_str << " " << message << std::endl;

        // Also log to file if configured
        if (g_log_file.is_open()) {
            g_log_file << type_str << " " << message << std::endl;
            g_log_file.flush();
        }
        return true;
    }
};

static DesktopSystemInterface g_system_interface;


static void PrintUsage() {
    std::cout << "Usage: mosis-designer [options] [document.rml]\n"
              << "\nOptions:\n"
              << "  --resolution WxH    Set window resolution (default: 540x960)\n"
              << "  --assets PATH       Set assets directory (default: derived from document)\n"
              << "  --log FILE          Write all log messages to file\n"
              << "  --hierarchy FILE    Continuously dump UI hierarchy to JSON\n"
              << "\nTest modes:\n"
              << "  --record FILE       Record user actions to JSON file\n"
              << "  --playback FILE     Playback actions from JSON file\n"
              << "  --screenshot FILE   Take screenshot and exit\n"
              << "  --dump-hierarchy FILE  Dump UI hierarchy to JSON and exit\n"
              << "\nKeys:\n"
              << "  F5    Reload document\n"
              << "  F12   Toggle RmlUi debugger\n"
              << "  ESC   Back navigation\n"
              << "  R     Start/Stop recording (in interactive mode)\n"
              << std::endl;
}

int main(int argc, char* argv[]) {
    std::cout << "Mosis Designer v0.1.0" << std::endl;

    // Parse arguments
    std::string document_path;
    std::string assets_path;  // Will be derived from document path if not specified
    bool assets_path_specified = false;

    for (int i = 1; i < argc; ++i) {
        std::string arg = argv[i];
        if (arg == "--help" || arg == "-h") {
            PrintUsage();
            return 0;
        } else if (arg == "--resolution" && i + 1 < argc) {
            std::string res = argv[++i];
            size_t x = res.find('x');
            if (x != std::string::npos) {
                g_width = std::stoi(res.substr(0, x));
                g_height = std::stoi(res.substr(x + 1));
            }
        } else if (arg == "--assets" && i + 1 < argc) {
            assets_path = argv[++i];
            assets_path_specified = true;
        } else if (arg == "--log" && i + 1 < argc) {
            g_log_file_path = argv[++i];
        } else if (arg == "--hierarchy" && i + 1 < argc) {
            g_hierarchy_file_path = argv[++i];
        } else if (arg == "--record" && i + 1 < argc) {
            g_test_mode = TestMode::Record;
            g_test_output_path = argv[++i];
        } else if (arg == "--playback" && i + 1 < argc) {
            g_test_mode = TestMode::Playback;
            g_test_input_path = argv[++i];
        } else if (arg == "--screenshot" && i + 1 < argc) {
            g_test_mode = TestMode::Screenshot;
            g_test_output_path = argv[++i];
        } else if (arg == "--dump-hierarchy" && i + 1 < argc) {
            g_test_mode = TestMode::DumpHierarchy;
            g_test_output_path = argv[++i];
        } else if (arg[0] != '-') {
            document_path = arg;
        }
    }

    // Default document
    if (document_path.empty()) {
        document_path = "apps/home/home.rml";
    }

    // Derive assets path from document path if not specified
    // The document path should be something like .../assets/apps/home/home.rml
    // We want to find the "assets" directory in the path
    if (!assets_path_specified) {
        fs::path doc_path = fs::absolute(document_path);
        fs::path current = doc_path.parent_path();

        // Walk up the directory tree looking for a folder that ends with "assets"
        // or contains typical asset folders like "apps", "ui", "fonts"
        while (!current.empty() && current.has_parent_path()) {
            std::string folder_name = current.filename().string();
            if (folder_name == "assets") {
                assets_path = current.string();
                break;
            }
            // Check if this folder contains typical asset subfolders
            if (fs::exists(current / "apps") && fs::exists(current / "ui")) {
                assets_path = current.string();
                break;
            }
            current = current.parent_path();
        }

        // Fall back to "assets" relative to executable if not found
        if (assets_path.empty()) {
            assets_path = "assets";
        }
    }

    // Make assets_path absolute
    assets_path = fs::absolute(assets_path).string();
    std::cout << "Assets path: " << assets_path << std::endl;
    std::cout << "Resolution: " << g_width << "x" << g_height << std::endl;

    // Print mode info
    if (g_test_mode == TestMode::Interactive) {
        std::cout << "Press F5 to reload, F12 for debugger, ESC for back, R to record" << std::endl;
    } else if (g_test_mode == TestMode::Record) {
        std::cout << "Recording mode: actions will be saved to " << g_test_output_path << std::endl;
    } else if (g_test_mode == TestMode::Playback) {
        std::cout << "Playback mode: playing " << g_test_input_path << std::endl;
    } else if (g_test_mode == TestMode::Screenshot) {
        std::cout << "Screenshot mode: will save to " << g_test_output_path << std::endl;
    } else if (g_test_mode == TestMode::DumpHierarchy) {
        std::cout << "Hierarchy dump mode: will save to " << g_test_output_path << std::endl;
    }

    // Open log file if specified
    if (!g_log_file_path.empty()) {
        g_log_file.open(g_log_file_path, std::ios::out | std::ios::trunc);
        if (g_log_file.is_open()) {
            std::cout << "Logging to: " << g_log_file_path << std::endl;
        } else {
            std::cerr << "Warning: Failed to open log file: " << g_log_file_path << std::endl;
        }
    }

    // Log hierarchy file path if specified
    if (!g_hierarchy_file_path.empty()) {
        std::cout << "Hierarchy dump to: " << g_hierarchy_file_path << std::endl;
    }

    // Initialize GLFW
    glfwSetErrorCallback(ErrorCallback);
    if (!glfwInit()) {
        std::cerr << "Failed to initialize GLFW" << std::endl;
        return 1;
    }
    
    // Create window with OpenGL 3.3 core context
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
    glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE);
    
    // Create window with document name in title
    std::string window_title = "Mosis Designer - " + fs::path(document_path).filename().string();
    g_window = glfwCreateWindow(g_width, g_height, window_title.c_str(), nullptr, nullptr);
    if (!g_window) {
        std::cerr << "Failed to create GLFW window" << std::endl;
        glfwTerminate();
        return 1;
    }
    
    glfwMakeContextCurrent(g_window);
    glfwSwapInterval(1); // VSync
    
    // Set callbacks
    glfwSetKeyCallback(g_window, KeyCallback);
    glfwSetMouseButtonCallback(g_window, MouseButtonCallback);
    glfwSetCursorPosCallback(g_window, CursorPosCallback);
    glfwSetScrollCallback(g_window, ScrollCallback);
    glfwSetFramebufferSizeCallback(g_window, FramebufferSizeCallback);
    
    // Load OpenGL functions with GLAD
    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
        std::cerr << "Failed to initialize GLAD" << std::endl;
        glfwDestroyWindow(g_window);
        glfwTerminate();
        return 1;
    }
    
    std::cout << "OpenGL " << glGetString(GL_VERSION) << std::endl;

    // Get actual framebuffer size (may differ from window size on HiDPI displays)
    int fb_width, fb_height;
    glfwGetFramebufferSize(g_window, &fb_width, &fb_height);
    std::cout << "Framebuffer size: " << fb_width << "x" << fb_height << std::endl;

    // Create platform abstraction and set as global singleton
    auto platform = std::make_unique<mosis::DesktopPlatform>(g_window, g_width, g_height);
    platform->SetAssetsPath(assets_path);
    g_platform = platform.get();
    mosis::SetPlatform(std::move(platform));

    // Initialize RmlUi (use framebuffer size for rendering, logical size for context)
    if (!InitializeRmlUi(assets_path, fb_width, fb_height)) {
        std::cerr << "Failed to initialize RmlUi" << std::endl;
        glfwDestroyWindow(g_window);
        glfwTerminate();
        return 1;
    }
    
    // Load initial document
    if (!LoadDocument(document_path)) {
        std::cerr << "Failed to load document: " << document_path << std::endl;
    }

    // Initialize test mode components
    if (g_test_mode == TestMode::Record) {
        g_action_recorder = new mosis::testing::ActionRecorder(g_width, g_height);
        g_action_recorder->StartRecording();
        std::cout << "Recording started. Close window to save." << std::endl;
    } else if (g_test_mode == TestMode::Playback) {
        g_action_player = new mosis::testing::ActionPlayer(g_context);
        if (!g_action_player->LoadFromFile(g_test_input_path)) {
            std::cerr << "Failed to load actions from: " << g_test_input_path << std::endl;
            delete g_action_player;
            g_action_player = nullptr;
        } else {
            g_action_player->Start();
            std::cout << "Playback started..." << std::endl;
        }
    }

    // Set up hot-reload (only in interactive mode)
    if (g_test_mode == TestMode::Interactive) {
        g_hot_reload = new mosis::HotReload(assets_path, []() {
            g_needs_reload = true;
        });
        g_hot_reload->Start();
        std::cout << "Hot-reload enabled for: " << assets_path << std::endl;
    }

    // For screenshot/hierarchy modes, render one frame then capture
    if (g_test_mode == TestMode::Screenshot || g_test_mode == TestMode::DumpHierarchy) {
        // Render one frame
        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);

        if (g_context) {
            g_context->Update();
            g_render_interface->BeginFrame();
            g_context->Render();
            g_render_interface->EndFrame(0);
        }

        glfwSwapBuffers(g_window);

        if (g_test_mode == TestMode::Screenshot) {
            mosis::testing::VisualCapture capture(fb_width, fb_height);
            if (capture.CaptureScreenshot(g_test_output_path)) {
                std::cout << "Screenshot saved to: " << g_test_output_path << std::endl;
            } else {
                std::cerr << "Failed to save screenshot" << std::endl;
            }
        } else {
            mosis::testing::UIInspector inspector(g_context);
            if (inspector.SaveHierarchy(g_test_output_path)) {
                std::cout << "UI hierarchy saved to: " << g_test_output_path << std::endl;
            } else {
                std::cerr << "Failed to save hierarchy" << std::endl;
            }
        }

        // Cleanup and exit
        ShutdownRmlUi();
        glfwDestroyWindow(g_window);
        glfwTerminate();
        return 0;
    }

    // Main loop
    while (!glfwWindowShouldClose(g_window)) {
        glfwPollEvents();

        // Handle hot-reload
        if (g_needs_reload) {
            g_needs_reload = false;
            ReloadDocument();
        }

        // Update action playback
        if (g_action_player && g_action_player->IsPlaying()) {
            g_action_player->Update();

            // Check if playback finished
            if (g_action_player->IsFinished()) {
                std::cout << "Playback complete" << std::endl;
                // Optionally exit after playback
                glfwSetWindowShouldClose(g_window, GLFW_TRUE);
            }
        }

        // Clear
        glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);

        // Update and render
        if (g_context) {
            g_context->Update();
            g_render_interface->BeginFrame();
            g_context->Render();
            g_render_interface->EndFrame(0);
        }

        // Dump UI hierarchy each frame if configured
        if (!g_hierarchy_file_path.empty() && g_context) {
            mosis::testing::UIInspector inspector(g_context);
            inspector.SetCurrentScreen(g_current_screen_url);
            inspector.SaveHierarchy(g_hierarchy_file_path);
        }

        glfwSwapBuffers(g_window);
    }

    // Save recording if in record mode
    if (g_action_recorder && g_action_recorder->IsRecording()) {
        g_action_recorder->StopRecording();
        if (g_action_recorder->SaveToFile(g_test_output_path)) {
            std::cout << "Recording saved to: " << g_test_output_path << std::endl;
        } else {
            std::cerr << "Failed to save recording" << std::endl;
        }
    }

    // Cleanup
    delete g_action_recorder;
    delete g_action_player;
    if (g_hot_reload) {
        g_hot_reload->Stop();
        delete g_hot_reload;
    }
    if (g_log_file.is_open()) {
        g_log_file.close();
    }
    ShutdownRmlUi();
    glfwDestroyWindow(g_window);
    glfwTerminate();

    return 0;
}


bool InitializeRmlUi(const std::string& assets_path, int fb_width, int fb_height) {
    // Create render interface
    g_render_interface = new RenderInterface_GL3();
    if (!*g_render_interface) {
        std::cerr << "Failed to create GL3 render interface" << std::endl;
        return false;
    }
    // Use framebuffer size (physical pixels) for the render interface viewport
    g_render_interface->SetViewport(fb_width, fb_height);

    // Initialize RmlUi
    Rml::SetSystemInterface(&g_system_interface);
    Rml::SetFileInterface(&g_platform->GetFileInterface());
    Rml::SetRenderInterface(g_render_interface);
    
    if (!Rml::Initialise()) {
        std::cerr << "Failed to initialize RmlUi" << std::endl;
        return false;
    }
    
    // Initialize Lua bindings
    Rml::Lua::Initialise();

    // Register loadScreen function for navigation
    lua_State* L = Rml::Lua::Interpreter::GetLuaState();
    lua_pushcfunction(L, [](lua_State* L) -> int {
        const char* path = luaL_checkstring(L, 1);

        if (!g_context) {
            lua_pushboolean(L, false);
            return 1;
        }

        // Close existing documents (except debugger)
        while (g_context->GetNumDocuments() > 1) {
            auto* doc = g_context->GetDocument(0);
            if (doc && doc->GetSourceURL().find("__rmlui") == std::string::npos) {
                doc->Close();
            } else {
                break;
            }
        }

        // Load new document
        auto* document = g_context->LoadDocument(path);
        if (document) {
            document->Show();
            g_current_document_path = path;
            g_current_screen_url = path;  // Track current screen for hierarchy dump
            // Log using RmlUi logging so it appears in log file
            Rml::Log::Message(Rml::Log::LT_INFO, "Loaded screen: %s", path);
            lua_pushboolean(L, true);
        } else {
            Rml::Log::Message(Rml::Log::LT_ERROR, "Failed to load screen: %s", path);
            lua_pushboolean(L, false);
        }
        return 1;
    });
    lua_setglobal(L, "loadScreen");
    std::cout << "Registered Lua loadScreen function" << std::endl;

    // Load fonts
    std::vector<std::string> fonts = {
        "fonts/LatoLatin-Regular.ttf",
        "fonts/LatoLatin-Bold.ttf",
        "fonts/LatoLatin-Light.ttf",
    };
    for (const auto& font : fonts) {
        if (!Rml::LoadFontFace(font)) {
            std::cerr << "Warning: Failed to load font: " << font << std::endl;
        }
    }
    
    // Create context
    g_context = Rml::CreateContext("main", Rml::Vector2i(g_width, g_height));
    if (!g_context) {
        std::cerr << "Failed to create RmlUi context" << std::endl;
        return false;
    }
    
    // Initialize debugger
    Rml::Debugger::Initialise(g_context);
    
    return true;
}

void ShutdownRmlUi() {
    if (g_context) {
        Rml::RemoveContext("main");
        g_context = nullptr;
    }

    // Rml::Lua is shut down automatically when Rml::Shutdown() is called
    Rml::Shutdown();

    delete g_render_interface;
    g_render_interface = nullptr;

    // Platform (and its file interface) is managed by the global singleton
}

bool LoadDocument(const std::string& path) {
    if (!g_context) return false;
    
    // Close existing documents
    while (g_context->GetNumDocuments() > 0) {
        auto* doc = g_context->GetDocument(0);
        if (doc) doc->Close();
    }
    
    // Load new document
    auto* document = g_context->LoadDocument(path);
    if (!document) {
        std::cerr << "Failed to load: " << path << std::endl;
        return false;
    }
    
    document->Show();
    g_current_document_path = path;
    g_current_screen_url = path;  // Track current screen for hierarchy dump
    std::cout << "Loaded: " << path << std::endl;

    return true;
}

void ReloadDocument() {
    std::cout << "Reloading..." << std::endl;
    
    // Reload stylesheets
    for (int i = 0; i < g_context->GetNumDocuments(); ++i) {
        auto* doc = g_context->GetDocument(i);
        if (doc) {
            doc->ReloadStyleSheet();
        }
    }
    
    // Reload document
    if (!g_current_document_path.empty()) {
        LoadDocument(g_current_document_path);
    }
    
    std::cout << "Reload complete" << std::endl;
}