#include "app.hpp"
#include "imgui-raii.hpp"
#include "anim-atlas.hpp"
#include "loader/loader.hpp"
#include "floormat/main.hpp"
#include <Magnum/Math/Color.h>

namespace floormat {

using namespace floormat::imgui;

namespace {

StringView scenery_type_to_string(const scenery_editor::scenery_& sc)
{
    switch (sc.proto.sc_type)
    {
    case scenery_type::none:    return "none"_s;
    case scenery_type::generic: return "generic"_s;
    case scenery_type::door:    return "door"_s;
    default:                    return "unknown"_s;
    }
}

std::shared_ptr<anim_atlas> get_atlas(const scenery_editor::scenery_& sc)
{
    return sc.proto.atlas;
}

StringView scenery_name(StringView name, const scenery_editor::scenery_&)
{
    return name;
}

template<typename T> struct do_group_column : std::bool_constant<false> {};
template<> struct do_group_column<scenery_editor> : std::bool_constant<true> {};

StringView scenery_type_to_string(const vobj_editor::vobj_& vobj)
{
    return vobj.name;
}

std::shared_ptr<anim_atlas> get_atlas(const vobj_editor::vobj_& vobj)
{
    return vobj.factory->atlas();
}

StringView scenery_name(StringView, const vobj_editor::vobj_& vobj)
{
    return vobj.descr;
}

} // namespace

template<typename T>
static void impl_draw_editor_scenery_pane(T& ed, Vector2 dpi)
{
    const auto b1 = push_id("scenery-pane");

    const auto& style = ImGui::GetStyle();
    constexpr ImGuiTableFlags flags = ImGuiTableFlags_BordersInnerV | ImGuiTableFlags_ScrollY;
    constexpr int ncolumns = do_group_column<T>::value ? 4 : 2;
    const auto size = ImGui::GetWindowSize();
    auto b2 = imgui::begin_table("scenery-table", ncolumns, flags, size);
    const auto row_height = ImGui::GetCurrentContext()->FontSize + 10*dpi[1];
    constexpr auto thumbnail_width = 50;
    ImGui::TableSetupScrollFreeze(1, 1);
    constexpr auto colflags_ = ImGuiTableColumnFlags_NoResize | ImGuiTableColumnFlags_NoReorder | ImGuiTableColumnFlags_NoSort;
    constexpr auto colflags = colflags_ | ImGuiTableColumnFlags_WidthFixed;
    ImGui::TableSetupColumn("##thumbnail", colflags, thumbnail_width);
    ImGui::TableSetupColumn("Name", colflags_ | ImGuiTableColumnFlags_WidthStretch);
    if constexpr(do_group_column<T>::value)
    {
        const auto colwidth_type = ImGui::CalcTextSize("generic").x;
        const auto colwidth_group = ImGui::CalcTextSize("MMMMMMMMMMMMMMM").x;
        ImGui::TableSetupColumn("Type", colflags, colwidth_type);
        ImGui::TableSetupColumn("Group", colflags, colwidth_group);
    }
    ImGui::TableHeadersRow();

    const auto click_event = [&] {
        if (ImGui::IsItemClicked(ImGuiMouseButton_Middle))
            ed.clear_selection();
    };
    click_event();

    for (const auto& [name, scenery] : ed)
    {
        fm_debug_assert(get_atlas(scenery));
        ImGui::TableNextRow(ImGuiTableRowFlags_None, row_height);

        if (ImGui::TableSetColumnIndex(0))
        {
            auto& atlas = *get_atlas(scenery);
            const auto r = atlas.first_rotation();
            const auto& frame = atlas.frame(r, 0);
            const auto size = Vector2(frame.size);
            const float c = std::min(thumbnail_width / size[0], row_height / size[1]);
            const auto texcoords = atlas.texcoords_for_frame(r, 0, !atlas.group(r).mirror_from.isEmpty());
            const ImVec2 img_size = {size[0]*c, size[1]*c+style.CellPadding.y + 0.5f};
            const ImVec2 uv0 {texcoords[3][0], texcoords[3][1]}, uv1 {texcoords[0][0], texcoords[0][1]};
            ImGui::SetCursorPosX(ImGui::GetCursorPosX() + std::max(0.f, .5f*(thumbnail_width - img_size.x)));
            ImGui::SetCursorPosY(ImGui::GetCursorPosY() + .5f*std::max(0.f, row_height - img_size.y));
            ImGui::Image((void*)&atlas.texture(), img_size, uv0, uv1);
            click_event();
        }
        if (ImGui::TableSetColumnIndex(1))
        {
            constexpr ImGuiSelectableFlags flags = ImGuiSelectableFlags_SpanAllColumns;
            bool selected = ed.is_item_selected(scenery);
            auto name_ = scenery_name(name, scenery);
            if (ImGui::Selectable(name_.data(), &selected, flags, {0, row_height}) && selected)
                ed.select_tile(scenery);
            click_event();
        }
        if (do_group_column<T>::value && ImGui::TableSetColumnIndex(2))
        {
            text(scenery_type_to_string(scenery));
            click_event();
        }
        if (do_group_column<T>::value && ImGui::TableSetColumnIndex(3))
        {
            auto& atlas = *get_atlas(scenery);
            StringView name = loader.strip_prefix(atlas.name());
            if (auto last = name.findLast('/'))
                name = name.prefix(last.data());
            else
                name = {};
            text(name);
            click_event();
        }
    }
}

template void impl_draw_editor_scenery_pane(scenery_editor&, Vector2);
template void impl_draw_editor_scenery_pane(vobj_editor&, Vector2);

void app::draw_editor_scenery_pane(scenery_editor& ed)
{
    impl_draw_editor_scenery_pane<scenery_editor>(ed, M->dpi_scale());
}

void app::draw_editor_vobj_pane(vobj_editor& ed)
{
    impl_draw_editor_scenery_pane<vobj_editor>(ed, M->dpi_scale());
}

void app::draw_editor_pane(float main_menu_height)
{
    auto* ed = _editor.current_tile_editor();
    auto* sc = _editor.current_scenery_editor();
    auto* vo = _editor.current_vobj_editor();
    fm_assert(!ed || !sc || !vo);

    const auto window_size = M->window_size();
    const auto dpi = M->dpi_scale();

    if (const bool active = M->is_text_input_active();
        ImGui::GetIO().WantTextInput != active)
        active ? M->start_text_input() : M->stop_text_input();

    [[maybe_unused]] const raii_wrapper vars[] = {
        push_style_var(ImGuiStyleVar_WindowPadding, {8*dpi[0], 8*dpi[1]}),
        push_style_var(ImGuiStyleVar_WindowBorderSize, 0),
        push_style_var(ImGuiStyleVar_FramePadding, {4*dpi[0], 4*dpi[1]}),
        push_style_color(ImGuiCol_WindowBg, {0, 0, 0, .5}),
        push_style_color(ImGuiCol_FrameBg, {0, 0, 0, 0}),
    };

    const auto& style = ImGui::GetStyle();

    if (main_menu_height > 0)
    {
        constexpr auto igwf = ImGuiWindowFlags_(ImGuiWindowFlags_NoDecoration |
                                                ImGuiWindowFlags_NoMove |
                                                ImGuiWindowFlags_NoSavedSettings);
        const auto b = push_id("editor");

        ImGui::SetNextWindowPos({0, main_menu_height+style.WindowPadding.y});
        ImGui::SetNextFrameWantCaptureKeyboard(false);
        ImGui::SetNextWindowSize({425 * dpi[0], window_size[1]-main_menu_height - style.WindowPadding.y});
        if (auto b = begin_window({}, nullptr, igwf))
        {
            const auto b2 = push_id("editor-pane");
            if (auto b3 = begin_list_box("##atlases", {-FLT_MIN, -1}))
            {
                if (ed)
                    for (const auto& [k, v] : *ed)
                        draw_editor_tile_pane_atlas(*ed, k, v);
                else if (sc)
                    draw_editor_scenery_pane(*sc);
                else if (vo)
                    draw_editor_vobj_pane(*vo);
            }
        }
    }
}

} // namespace floormat