#include "viewer.h"
#include "image_handler.h"
#include "radiation_handler.h"
#include "core/config.h"
#include "products/dataset.h"
#include "common/utils.h"

namespace satdump
{
    ViewerApplication::ViewerApplication()
        : Application("viewer")
    {
        // pro.load("/home/alan/Documents/SatDump_ReWork/build/metop_ahrpt_new/AVHRR/product.cbor");
        //  pro.load("/home/alan/Documents/SatDump_ReWork/build/aqua_test_new/MODIS/product.cbor");

        loadDatasetInViewer("/home/alan/Documents/SatDump_ReWork/build/metop_ahrpt_new/dataset.json");

        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/noaa_mhs_test/AMSU/product.cbor", "NOAA-19 HRPT");
        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/metop_ahrpt_new/AVHRR/product.cbor", "MetOp-B AHRPT");
        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/noaa_mhs_test/MHS/product.cbor", "NOAA-19 HRPT");
        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/noaa_mhs_test_gac/MHS/product.cbor", "NOAA-19 GAC");
        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/noaa_mhs_test_gac/HIRS/product.cbor", "NOAA-19 GAC");
        // loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/noaa_mhs_test_gac/AVHRR/product.cbor", "NOAA-19 GAC");
        loadProductsInViewer("/home/alan/Documents/SatDump_ReWork/build/npp_hrd_new/VIIRS/product.cbor", "JPSS-1 HRD");
    }

    void ViewerApplication::loadDatasetInViewer(std::string path)
    {
        ProductDataSet dataset;
        dataset.load(path);

        std::string pro_directory = std::filesystem::path(path).parent_path();
        for (std::string pro_path : dataset.products_list)
            loadProductsInViewer(pro_directory + "/" + pro_path, dataset.satellite_name + " " + timestamp_to_string(dataset.timestamp));
    }

    void ViewerApplication::loadProductsInViewer(std::string path, std::string dataset_name)
    {
        if (std::filesystem::exists(path))
        {
            std::shared_ptr<Products> products = loadProducts(path);

            // Get instrument settings
            nlohmann::ordered_json instrument_viewer_settings;
            if (config::main_cfg["viewer"]["instruments"].contains(products->instrument_name))
                instrument_viewer_settings = config::main_cfg["viewer"]["instruments"][products->instrument_name];
            else
                logger->error("Unknown instrument : {:s}!", products->instrument_name);

            // Init Handler
            std::string handler_id = instrument_viewer_settings["handler"].get<std::string>();
            logger->debug("Using handler {:s} for instrument {:s}", handler_id, products->instrument_name);
            std::shared_ptr<ViewerHandler> handler = viewer_handlers_registry[handler_id]();

            handler->products = products.get();
            handler->instrument_cfg = instrument_viewer_settings;
            handler->init();

            if (dataset_name != "")
            {
                bool dataset_exists = false;
                for (std::string dataset_name2 : opened_datasets)
                    dataset_exists = dataset_exists | dataset_name2 == dataset_name;

                if (!dataset_exists)
                    opened_datasets.push_back(dataset_name);
            }

            // Push products and handler
            products_and_handlers.push_back({products, handler, dataset_name});
        }
    }

    ViewerApplication::~ViewerApplication()
    {
    }

    ImRect ViewerApplication::renderHandler(ProductsHandler &ph, int index)
    {
        std::string label = ph.products->instrument_name;
        if (ph.handler->instrument_cfg.contains("name"))
            label = ph.handler->instrument_cfg["name"].get<std::string>();

        ImGui::TreeNodeEx(label.c_str(), ImGuiTreeNodeFlags_Leaf | ImGuiTreeNodeFlags_NoTreePushOnOpen | (index == current_handler_id ? ImGuiTreeNodeFlags_Selected : 0));
        if (ImGui::IsItemClicked())
            current_handler_id = index;

        ImRect rect = ImRect(ImGui::GetItemRectMin(), ImGui::GetItemRectMax());

        if (index == current_handler_id)
        {
            ImGui::TreePush();
            products_and_handlers[current_handler_id].handler->drawTreeMenu();
            ImGui::TreePop();
        }
        // ImGui::InputInt("Current Product", &current_handler_id);

        return rect;
    }

    void ViewerApplication::drawPanel()
    {
        if (ImGui::CollapsingHeader("General"))
        {
            for (std::string dataset_name : opened_datasets)
            {
                if (products_cnt_in_dataset(dataset_name))
                {
                    ImGui::TreeNodeEx(dataset_name.c_str(), ImGuiTreeNodeFlags_Leaf | ImGuiTreeNodeFlags_NoTreePushOnOpen);
                    ImGui::TreePush();

                    const ImColor TreeLineColor = ImColor(128, 128, 128, 255); // ImGui::GetColorU32(ImGuiCol_Text);
                    const float SmallOffsetX = 11.0f;                          // for now, a hardcoded value; should take into account tree indent size
                    ImDrawList *drawList = ImGui::GetWindowDrawList();

                    ImVec2 verticalLineStart = ImGui::GetCursorScreenPos();
                    verticalLineStart.x += SmallOffsetX; // to nicely line up with the arrow symbol
                    ImVec2 verticalLineEnd = verticalLineStart;

                    for (int i = 0; i < products_and_handlers.size(); i++)
                        if (products_and_handlers[i].dataset_name == dataset_name)
                        {
                            const float HorizontalTreeLineSize = 8.0f;                           // chosen arbitrarily
                            const ImRect childRect = renderHandler(products_and_handlers[i], i); // RenderTree(child);
                            const float midpoint = (childRect.Min.y + childRect.Max.y) / 2.0f;
                            drawList->AddLine(ImVec2(verticalLineStart.x, midpoint), ImVec2(verticalLineStart.x + HorizontalTreeLineSize, midpoint), TreeLineColor);
                            verticalLineEnd.y = midpoint;
                        }

                    drawList->AddLine(verticalLineStart, verticalLineEnd, TreeLineColor);

                    ImGui::TreePop();
                }
            }

            // Render unclassified
            if (products_cnt_in_dataset(""))
            {
                ImGui::TreeNodeEx("Others", ImGuiTreeNodeFlags_Leaf | ImGuiTreeNodeFlags_NoTreePushOnOpen);
                ImGui::TreePush();
                for (int i = 0; i < products_and_handlers.size(); i++)
                    if (products_and_handlers[i].dataset_name == "")
                        renderHandler(products_and_handlers[i], i);
                ImGui::TreePop();
            }
        }
    }

    void ViewerApplication::drawContent()
    {
    }

    void ViewerApplication::drawUI()
    {
        ImVec2 viewer_size = ImGui::GetContentRegionAvail();
        ImGui::BeginGroup();
        ImGui::BeginChild("ViewerChildPanel", {viewer_size.x * 0.20, viewer_size.y}, false);
        {
            drawPanel();
            products_and_handlers[current_handler_id].handler->drawMenu();
        }
        ImGui::EndChild();
        ImGui::EndGroup();

        ImGui::SameLine();

        ImGui::BeginGroup();
        products_and_handlers[current_handler_id].handler->drawContents({viewer_size.x * 0.80 - 4, viewer_size.y});
        ImGui::EndGroup();
    }

    std::map<std::string, std::function<std::shared_ptr<ViewerHandler>()>> viewer_handlers_registry;
    void registerViewerHandlers()
    {
        viewer_handlers_registry.emplace(ImageViewerHandler::getID(), ImageViewerHandler::getInstance);
        viewer_handlers_registry.emplace(RadiationViewerHandler::getID(), RadiationViewerHandler::getInstance);
    }
};