#include "proclamation_options_page.h"
#include "app_state.h"
#include "network/proclamation_sync.h"
#include "logical_size.h"
#include <SDL3/SDL.h>
#include <algorithm>
#include <cctype>
#include <cstring>

namespace {

// Case-insensitive word-prefix match: true when any word in `text` (split on
// non-alphanumeric boundaries) starts with `query`. Both must already be
// lowercase. Mirrors the old Go browser's matching behavior.
bool matchesWordPrefix(const std::string& text, const std::string& query)
{
    if (query.empty()) return false;

    size_t i = 0;
    while (i < text.size()) {
        while (i < text.size() &&
               !std::isalnum(static_cast<unsigned char>(text[i]))) {
            ++i;
        }
        if (i >= text.size()) break;

        size_t start = i;
        while (i < text.size() &&
               std::isalnum(static_cast<unsigned char>(text[i]))) {
            ++i;
        }
        if (text.compare(start, query.size(), query) == 0) return true;
    }
    return false;
}

} // anonymous namespace

void ProclamationOptionsPage::onPush(AppState& state)
{
    state_ = &state;
    TTF_Init();
    createFonts();
    SDL_StartTextInput(state.window);

    // TODO(portal #4/#5): once the portal exposes color palettes, sync them
    // alongside proclamations here (sync::syncColorPalettesFromApi after this
    // succeeds) so palette updates reach the scroller on every manual refresh.
    bool synced = radiantwave::sync::syncProclamationsFromApi(state.db, DEFAULT_PROPLEAMATION_ID);
    statusMessage_ = synced
        ? "Synced with server"
        : "Offline - showing saved proclamations";

    loadFromDb();
    rebuildItems();
    rebuildVisible();

    state.keybinds.bind(SDLK_UP, "proc_up", [this]() {
        if (highlightIndex_ > 0) {
            highlightIndex_--;
            ensureHighlightVisible();
        }
    });
    state.keybinds.bind(SDLK_DOWN, "proc_down", [this]() {
        if (highlightIndex_ < activeListSize() - 1) {
            highlightIndex_++;
            ensureHighlightVisible();
        }
    });
    state.keybinds.bind(SDLK_D, SDL_KMOD_CTRL, "proc_clear_all", [this]() {
        clearAllSelections();
    });
}

void ProclamationOptionsPage::onResume(AppState& state)
{
    state_ = &state;
    createFonts();
    SDL_StartTextInput(state.window);

    loadFromDb();
    rebuildItems();
    rebuildVisible();

    state.keybinds.bind(SDLK_UP, "proc_up", [this]() {
        if (highlightIndex_ > 0) {
            highlightIndex_--;
            ensureHighlightVisible();
        }
    });
    state.keybinds.bind(SDLK_DOWN, "proc_down", [this]() {
        if (!visible_.empty() && highlightIndex_ < static_cast<int>(visible_.size()) - 1) {
            highlightIndex_++;
            ensureHighlightVisible();
        }
    });
    state.keybinds.bind(SDLK_D, SDL_KMOD_CTRL, "proc_clear_all", [this]() {
        clearAllSelections();
    });
}

void ProclamationOptionsPage::onPause(AppState& state)
{
    state.keybinds.unbindAll();
    SDL_StopTextInput(state.window);
    destroyFonts();
    destroyTextures();
}

void ProclamationOptionsPage::onPop(AppState& state)
{
    state.keybinds.unbindAll();
    SDL_StopTextInput(state.window);
    destroyFonts();
    destroyTextures();
    TTF_Quit();
}

void ProclamationOptionsPage::createFonts()
{
    destroyFonts();
    fontTitle_ = TTF_OpenFont("assets/fonts/Roboto-Regular.ttf", 48);
    fontItem_ = TTF_OpenFont("assets/fonts/Roboto-Regular.ttf", 36);
    fontSmall_ = TTF_OpenFont("assets/fonts/Roboto-Regular.ttf", 20);
}

void ProclamationOptionsPage::destroyFonts()
{
    if (fontTitle_) { TTF_CloseFont(fontTitle_); fontTitle_ = nullptr; }
    if (fontItem_) { TTF_CloseFont(fontItem_); fontItem_ = nullptr; }
    if (fontSmall_) { TTF_CloseFont(fontSmall_); fontSmall_ = nullptr; }
}

void ProclamationOptionsPage::destroyTextures()
{
    titleText_.destroy();
    statusText_.destroy();
    searchText_.destroy();
    emptyHintText_.destroy();
    footerText_.destroy();
    for (auto& t : rowTexts_) t.destroy();
    rowTexts_.clear();
    for (auto& t : searchRowTexts_) t.destroy();
    searchRowTexts_.clear();
}

void ProclamationOptionsPage::loadFromDb()
{
    proclamations_ = state_->db.getAllProclamations();
    categories_ = state_->db.getAllCategories();

    state_->db.ensureDefaultProclamationSelected(DEFAULT_PROPLEAMATION_ID);
    for (auto& p : proclamations_) {
        if (p.id == DEFAULT_PROPLEAMATION_ID) {
            p.selected = true;
        }
    }

    searchPool_.clear();
    searchPool_.reserve(proclamations_.size());
    for (const auto& p : proclamations_) {
        std::string lower = p.title;
        lower += ' ';
        lower += p.content;
        for (auto& c : lower) {
            if (c >= 'A' && c <= 'Z') c = static_cast<char>(c - 'A' + 'a');
        }
        searchPool_.push_back(std::move(lower));
    }
}

void ProclamationOptionsPage::rebuildItems()
{
    items_.clear();

    // Always-on top-level proclamation, never inside a category.
    items_.push_back({
        FlatItem::Type::Proclamation,
        DEFAULT_PROPLEAMATION_ID,
        DEFAULT_PROPLEAMATION_NAME,
        0, false, true, true,
    });

    for (const auto& root : categories_) {
        if (root.parent_id != 0) continue;

        items_.push_back({
            FlatItem::Type::RootCategory,
            std::to_string(root.id),
            root.name,
            0, false, false, false,
        });

        for (const auto& sub : categories_) {
            if (sub.parent_id != root.id) continue;

            items_.push_back({
                FlatItem::Type::SubCategory,
                std::to_string(sub.id),
                sub.name,
                1, true, false, false,
            });

            for (const auto& p : proclamations_) {
                if (p.id == DEFAULT_PROPLEAMATION_ID) continue;
                if (p.category_id != sub.id) continue;
                items_.push_back({
                    FlatItem::Type::Proclamation,
                    p.id,
                    p.title,
                    2, false, p.selected, false,
                });
            }
        }

        // Proclamations assigned directly to the root category.
        for (const auto& p : proclamations_) {
            if (p.id == DEFAULT_PROPLEAMATION_ID) continue;
            if (p.category_id != root.id) continue;
            items_.push_back({
                FlatItem::Type::Proclamation,
                p.id,
                p.title,
                1, false, p.selected, false,
            });
        }
    }
}

void ProclamationOptionsPage::rebuildVisible()
{
    visible_.clear();
    if (items_.empty()) {
        highlightIndex_ = 0;
        return;
    }

    // Tree walk: track the currently-open root and sub category (items_ is
    // already ordered root -> sub -> proclamation, so each category dominates
    // the items until the next category of equal or shallower depth).
    int currentRoot = -1; // items_ index of the current root category
    int currentSub = -1;  // items_ index of the current sub-category

    for (size_t i = 0; i < items_.size(); ++i) {
        const FlatItem& item = items_[i];

        if (item.type == FlatItem::Type::RootCategory) {
            currentRoot = static_cast<int>(i);
            currentSub = -1;
            visible_.push_back(i);
            continue;
        }

        if (item.type == FlatItem::Type::SubCategory) {
            bool rootOpen = currentRoot >= 0 && items_[currentRoot].expanded;
            if (rootOpen) {
                currentSub = static_cast<int>(i);
                visible_.push_back(i);
            } else {
                currentSub = -1;
            }
            continue;
        }

        // Proclamation
        bool parentVisible = false;
        if (item.depth == 0) {
            parentVisible = true; // the always-on top-level proclamation
        } else if (currentRoot >= 0 && items_[currentRoot].expanded) {
            parentVisible = (item.depth == 1) ||
                            (item.depth == 2 && currentSub >= 0);
        }
        if (parentVisible) visible_.push_back(i);
    }

    if (highlightIndex_ >= static_cast<int>(visible_.size())) {
        highlightIndex_ = std::max(0, static_cast<int>(visible_.size()) - 1);
    }
}

void ProclamationOptionsPage::toggleItem()
{
    if (visible_.empty()) return;
    FlatItem& item = items_[visible_[highlightIndex_]];

    if (item.type == FlatItem::Type::RootCategory) {
        item.expanded = !item.expanded;
        rebuildVisible();
        return;
    }

    if (item.isDefault) {
        statusMessage_ = "The top-level proclamation is always on";
        return;
    }

    item.selected = !item.selected;
    for (auto& p : proclamations_) {
        if (p.id == item.id) {
            p.selected = item.selected;
            break;
        }
    }
    saveSelectionToDb();
}

void ProclamationOptionsPage::enterSearchMode()
{
    if (searchActive_) return;
    searchActive_ = true;
    searchResults_.clear();
    highlightIndex_ = 0;
    scrollOffset_ = 0;
}

void ProclamationOptionsPage::exitSearchMode()
{
    searchActive_ = false;
    searchQuery_.clear();
    searchResults_.clear();
    highlightIndex_ = 0;
    scrollOffset_ = 0;
    rebuildVisible();
}

// Appends the printable ASCII portion of a UTF-8 text-input event to the
// query. Non-ASCII (and control) characters are dropped; the search list is
// rebuilt on every change.
void ProclamationOptionsPage::appendSearchText(const char* utf8)
{
    for (const unsigned char* p = reinterpret_cast<const unsigned char*>(utf8);
         p && *p; ++p) {
        unsigned char c = *p;
        if (c >= 0x20 && c <= 0x7E) searchQuery_ += static_cast<char>(c);
    }
    rebuildSearchResults();
}

void ProclamationOptionsPage::rebuildSearchResults()
{
    searchResults_.clear();
    for (size_t i = 0; i < proclamations_.size(); ++i) {
        if (matchesWordPrefix(searchPool_[i], searchQuery_)) {
            searchResults_.push_back(i);
        }
    }
    if (highlightIndex_ >= static_cast<int>(searchResults_.size())) {
        highlightIndex_ = std::max(0, static_cast<int>(searchResults_.size()) - 1);
    }
    if (scrollOffset_ >= static_cast<int>(searchResults_.size())) {
        scrollOffset_ = 0;
    }
    ensureHighlightVisible();
}

int ProclamationOptionsPage::activeListSize() const
{
    return searchActive_
        ? static_cast<int>(searchResults_.size())
        : static_cast<int>(visible_.size());
}

// Toggles the highlighted search result. Selection rules mirror toggleItem():
// the always-on top-level proclamation is not togglable. Selection state is
// synced back into items_ so the browse tree stays consistent when search mode
// ends.
void ProclamationOptionsPage::toggleSearchItem()
{
    if (searchResults_.empty()) return;
    radiantwave::db::ProclamationRecord& p = proclamations_[searchResults_[highlightIndex_]];

    if (p.id == DEFAULT_PROPLEAMATION_ID) {
        statusMessage_ = "The top-level proclamation is always on";
        return;
    }

    p.selected = !p.selected;
    for (auto& item : items_) {
        if (item.type == FlatItem::Type::Proclamation && item.id == p.id) {
            item.selected = p.selected;
            break;
        }
    }
    saveSelectionToDb();
}

void ProclamationOptionsPage::collapseCurrent()
{
    if (visible_.empty()) return;
    FlatItem& item = items_[visible_[highlightIndex_]];
    if (item.type == FlatItem::Type::RootCategory) {
        if (item.expanded) {
            item.expanded = false;
            rebuildVisible();
        }
    }
}

void ProclamationOptionsPage::expandCurrent()
{
    if (visible_.empty()) return;
    FlatItem& item = items_[visible_[highlightIndex_]];
    if (item.type == FlatItem::Type::RootCategory) {
        if (!item.expanded) {
            item.expanded = true;
            rebuildVisible();
        }
    }
}

void ProclamationOptionsPage::moveToParent()
{
    if (visible_.empty()) return;
    const FlatItem& item = items_[visible_[highlightIndex_]];
    if (item.depth <= 0) return;

    int start = static_cast<int>(visible_[highlightIndex_]);
    for (int i = start - 1; i >= 0; --i) {
        const FlatItem& candidate = items_[i];
        if ((candidate.type == FlatItem::Type::RootCategory ||
             candidate.type == FlatItem::Type::SubCategory) &&
            candidate.depth == item.depth - 1) {
            for (size_t vi = 0; vi < visible_.size(); ++vi) {
                if (visible_[vi] == static_cast<size_t>(i)) {
                    highlightIndex_ = static_cast<int>(vi);
                    ensureHighlightVisible();
                    return;
                }
            }
        }
    }
}

void ProclamationOptionsPage::saveSelectionToDb()
{
    std::vector<std::string> selected;
    for (const auto& p : proclamations_) {
        if (p.selected) selected.push_back(p.id);
    }
    state_->db.saveSelectedProclamations(selected, DEFAULT_PROPLEAMATION_ID);
}

// Deselects every proclamation except the always-on top-level one. The
// highlight keeps its current row and the list rebuilds so category/selection
// state (and the DB) all stay consistent.
void ProclamationOptionsPage::clearAllSelections()
{
    for (auto& p : proclamations_) {
        p.selected = (p.id == DEFAULT_PROPLEAMATION_ID);
    }
    saveSelectionToDb();
    rebuildItems();
    rebuildVisible();
    if (searchActive_) {
        rebuildSearchResults();
    }
    statusMessage_ = "All selections cleared (top-level proclamation stays on)";
}

void ProclamationOptionsPage::ensureHighlightVisible()
{
    if (highlightIndex_ < scrollOffset_) {
        scrollOffset_ = highlightIndex_;
    }
    int windowEnd = scrollOffset_ + visibleCount_;
    if (highlightIndex_ >= windowEnd) {
        scrollOffset_ = highlightIndex_ - visibleCount_ + 1;
    }
    if (scrollOffset_ < 0) scrollOffset_ = 0;
}

void ProclamationOptionsPage::scrollTo(int target)
{
    int maxScroll = std::max(0, activeListSize() - visibleCount_);
    scrollOffset_ = std::clamp(target, 0, maxScroll);
    if (highlightIndex_ < scrollOffset_ || highlightIndex_ >= scrollOffset_ + visibleCount_) {
        highlightIndex_ = scrollOffset_;
    }
}

void ProclamationOptionsPage::handleEvent(const SDL_Event& event)
{
    if (!state_) return;

    // Printable characters arrive as text input. The first non-space character
    // opens search; while search is active every printable character —
    // including space — is appended to the query.
    if (event.type == SDL_EVENT_TEXT_INPUT) {
        const char* text = event.text.text;
        if (!text || text[0] == '\0') return;

        if (!searchActive_) {
            if (strcmp(text, " ") == 0) return; // bare space does not open search
            bool printable = true;
            for (const unsigned char* p = reinterpret_cast<const unsigned char*>(text); *p; ++p) {
                if (*p < 0x20 || *p > 0x7E) {
                    printable = false;
                    break;
                }
            }
            if (!printable) return;
            enterSearchMode();
        }
        appendSearchText(text);
        return;
    }

    if (event.type != SDL_EVENT_KEY_DOWN) return;
    SDL_Keycode key = event.key.key;

    // SPACE is deliberately not handled here: it never selects a proclamation
    // (Enter does); its text-input event types a space into the search query.
    if (key == SDLK_RETURN || key == SDLK_KP_ENTER) {
        if (searchActive_) toggleSearchItem();
        else toggleItem();
    } else if (key == SDLK_BACKSPACE) {
        if (searchActive_ && !searchQuery_.empty()) {
            searchQuery_.pop_back();
            if (searchQuery_.empty()) {
                exitSearchMode();
            } else {
                rebuildSearchResults();
            }
        }
    } else if (key == SDLK_LEFT) {
        if (searchActive_) return;
        if (!visible_.empty()) {
            const FlatItem& item = items_[visible_[highlightIndex_]];
            if (item.type == FlatItem::Type::RootCategory && item.expanded) {
                collapseCurrent();
            } else {
                moveToParent();
            }
        }
    } else if (key == SDLK_RIGHT) {
        if (searchActive_) return;
        expandCurrent();
    } else if (key == SDLK_PAGEUP) {
        scrollTo(std::max(0, scrollOffset_ - visibleCount_ + 1));
    } else if (key == SDLK_PAGEDOWN) {
        scrollTo(scrollOffset_ + visibleCount_ - 1);
    } else if (key == SDLK_ESCAPE) {
        if (searchActive_) exitSearchMode();
        else state_->pages.pop(*state_);
    }
}

void ProclamationOptionsPage::update(float dt)
{
}

void ProclamationOptionsPage::render(SDL_Renderer* renderer)
{
    int winW, winH;
    radiantwave::getLayoutSize(renderer, &winW, &winH);
    float fw = static_cast<float>(winW);
    float fh = static_cast<float>(winH);

    // Background
    SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND);
    SDL_SetRenderDrawColor(renderer, 15, 18, 25, 255);
    SDL_FRect bgRect{0, 0, fw, fh};
    SDL_RenderFillRect(renderer, &bgRect);

    if (!fontTitle_ || !fontItem_ || !fontSmall_) return;

    SDL_Color white = {255, 255, 255, 255};
    SDL_Color gray = {170, 170, 170, 255};
    SDL_Color categoryBlue = {100, 180, 255, 255};
    SDL_Color selectedOrange = {255, 170, 60, 255};

    float titleY = 50.0f;
    float titleH = 0.0f;

    // 1. Title
    titleText_.ensure(renderer, fontTitle_, "Proclamation Options", white);
    if (titleText_.texture) {
        float x = (fw - titleText_.width) / 2.0f;
        SDL_FRect dst{x, titleY, titleText_.width, titleText_.height};
        SDL_RenderTexture(renderer, titleText_.texture, nullptr, &dst);
        titleH = titleText_.height;
    }

    // 2. Status line. The always-on top-level proclamation is not counted,
    // so the number reflects only what the user explicitly selected.
    float statusY = titleY + titleH + 12.0f;
    float searchBarY = statusY;
    {
        int selectedCount = 0;
        for (const auto& p : proclamations_) {
            if (p.selected && p.id != DEFAULT_PROPLEAMATION_ID) selectedCount++;
        }
        std::string status = statusMessage_ + "     Selected: " + std::to_string(selectedCount);
        statusText_.ensure(renderer, fontSmall_, status, gray);
        if (statusText_.texture) {
            float x = (fw - statusText_.width) / 2.0f;
            SDL_FRect dst{x, statusY, statusText_.width, statusText_.height};
            SDL_RenderTexture(renderer, statusText_.texture, nullptr, &dst);
        }
    }

    // 2b. Search bar (only while searching).
    if (searchActive_) {
        searchBarY = statusY + statusText_.height + 14.0f;
        SDL_Color searchYellow = {255, 230, 100, 255};
        std::string label = "Search: " + searchQuery_ + "|";
        searchText_.ensure(renderer, fontSmall_, label, searchYellow);
        if (searchText_.texture) {
            float x = (fw - searchText_.width) / 2.0f;
            SDL_FRect dst{x, searchBarY, searchText_.width, searchText_.height};
            SDL_RenderTexture(renderer, searchText_.texture, nullptr, &dst);
        }
    }

    // 3. List
    {
        const float margin = 12.0f;
        const float indent = 28.0f;
        float itemH = 42.0f;
        int strW = 0, strH = 0;
        TTF_GetStringSize(fontItem_, "Ag", 0, &strW, &strH);
        itemH = static_cast<float>(strH);
        float rowPitch = itemH + margin;

        float listTop = searchBarY + 40.0f;
        float footerTop = fh - 55.0f;
        float available = footerTop - listTop;
        visibleCount_ = std::max(1, static_cast<int>(available / rowPitch));

        int listSize = activeListSize();
        if (listSize == 0) {
            visibleCount_ = 1;
        }

        // Clamp scroll/highlight to the visible window.
        int maxScroll = std::max(0, listSize - visibleCount_);
        if (scrollOffset_ > maxScroll) scrollOffset_ = maxScroll;
        if (highlightIndex_ >= listSize) {
            highlightIndex_ = std::max(0, listSize - 1);
        }
        if (highlightIndex_ < scrollOffset_ || highlightIndex_ >= scrollOffset_ + visibleCount_) {
            if (highlightIndex_ < scrollOffset_) scrollOffset_ = highlightIndex_;
            else scrollOffset_ = highlightIndex_ - visibleCount_ + 1;
            if (scrollOffset_ < 0) scrollOffset_ = 0;
        }

        if (searchActive_) {
            // --- Search results (flat proclamation pool, no categories) ---
            if (searchResults_.empty()) {
                emptyHintText_.ensure(renderer, fontSmall_, "No matching proclamations", gray);
                if (emptyHintText_.texture) {
                    float x = (fw - emptyHintText_.width) / 2.0f;
                    SDL_FRect dst{x, listTop, emptyHintText_.width, emptyHintText_.height};
                    SDL_RenderTexture(renderer, emptyHintText_.texture, nullptr, &dst);
                }
            } else {
                // Stable width: compute from every result so the list doesn't shift.
                float maxTotalWidth = 0.0f;
                for (const auto& r : searchResults_) {
                    int w = 0, h = 0;
                    TTF_GetStringSize(fontItem_, proclamations_[r].title.c_str(), 0, &w, &h);
                    maxTotalWidth = std::max(maxTotalWidth, static_cast<float>(w));
                }

                std::vector<float> textWidths(static_cast<size_t>(listSize));
                for (int i = scrollOffset_; i < scrollOffset_ + visibleCount_ && i < listSize; ++i) {
                    int w = 0, h = 0;
                    TTF_GetStringSize(fontItem_, proclamations_[searchResults_[i]].title.c_str(), 0, &w, &h);
                    textWidths[i] = static_cast<float>(w);
                }
                float sharedX = (fw - maxTotalWidth) / 2.0f;

                if (searchRowTexts_.size() != proclamations_.size()) searchRowTexts_.resize(proclamations_.size());

                int rowIndex = 0;
                for (int i = scrollOffset_; i < scrollOffset_ + visibleCount_ && i < listSize; ++i, ++rowIndex) {
                    const radiantwave::db::ProclamationRecord& p = proclamations_[searchResults_[i]];
                    float y = listTop + rowIndex * rowPitch;

                    SDL_Color color = white;
                    if (p.selected) {
                        color = selectedOrange;
                    }

                    searchRowTexts_[searchResults_[i]].ensure(renderer, fontItem_, p.title, color);
                    if (searchRowTexts_[searchResults_[i]].texture) {
                        SDL_FRect dst{sharedX, y, searchRowTexts_[searchResults_[i]].width, searchRowTexts_[searchResults_[i]].height};
                        SDL_RenderTexture(renderer, searchRowTexts_[searchResults_[i]].texture, nullptr, &dst);
                    }

                    // 6px selection underline (occupies half the 12px margin).
                    if (i == highlightIndex_) {
                        SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
                        SDL_FRect line{sharedX, y + itemH + 2.0f, textWidths[i], 6.0f};
                        SDL_RenderFillRect(renderer, &line);
                    }
                }
            }
        } else {
            // --- Browse tree ---
            // Stable width: compute from every item so the list doesn't
            // shift left/right when groups expand or collapse.
            float maxTotalWidth = 0.0f;
            for (const auto& item : items_) {
                std::string label = item.label;
                if (item.type == FlatItem::Type::RootCategory) {
                    label = (item.expanded ? "[-] " : "[+] ") + label;
                }
                int w = 0, h = 0;
                TTF_GetStringSize(fontItem_, label.c_str(), 0, &w, &h);
                float total = item.depth * indent + static_cast<float>(w);
                maxTotalWidth = std::max(maxTotalWidth, total);
            }

            std::vector<float> textWidths(visible_.size());
            for (int i = scrollOffset_; i < scrollOffset_ + visibleCount_ && i < static_cast<int>(visible_.size()); ++i) {
                const FlatItem& item = items_[visible_[i]];
                std::string label = item.label;
                if (item.type == FlatItem::Type::RootCategory) {
                    label = (item.expanded ? "[-] " : "[+] ") + label;
                }
                int w = 0, h = 0;
                TTF_GetStringSize(fontItem_, label.c_str(), 0, &w, &h);
                textWidths[i] = static_cast<float>(w);
            }

            float sharedX = (fw - maxTotalWidth) / 2.0f;

            if (rowTexts_.size() != items_.size()) rowTexts_.resize(items_.size());

            int rowIndex = 0;
            for (int i = scrollOffset_; i < scrollOffset_ + visibleCount_ && i < static_cast<int>(visible_.size()); ++i, ++rowIndex) {
                const FlatItem& item = items_[visible_[i]];
                float y = listTop + rowIndex * rowPitch;

                std::string label = item.label;
                if (item.type == FlatItem::Type::RootCategory) {
                    label = (item.expanded ? "[-] " : "[+] ") + label;
                }

                SDL_Color color = white;
                if (item.type == FlatItem::Type::RootCategory || item.type == FlatItem::Type::SubCategory) {
                    color = categoryBlue;
                } else if (item.selected || item.isDefault) {
                    color = selectedOrange;
                }

                float x = sharedX + item.depth * indent;
                rowTexts_[visible_[i]].ensure(renderer, fontItem_, label, color);
                if (rowTexts_[visible_[i]].texture) {
                    SDL_FRect dst{x, y, rowTexts_[visible_[i]].width, rowTexts_[visible_[i]].height};
                    SDL_RenderTexture(renderer, rowTexts_[visible_[i]].texture, nullptr, &dst);
                }

                // 6px selection underline (occupies half the 12px margin).
                if (i == highlightIndex_) {
                    SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
                    SDL_FRect line{x, y + itemH + 2.0f, textWidths[i], 6.0f};
                    SDL_RenderFillRect(renderer, &line);
                }
            }
        }
    }

    // 4. Footer (mode-specific hints; ENTER selects, SPACE never does).
    if (searchActive_) {
        footerText_.ensure(renderer, fontSmall_,
            "[UP/DOWN] Move    [ENTER] Select    [BACKSPACE] Edit    [ESC] Cancel Search", gray);
    } else {
        footerText_.ensure(renderer, fontSmall_,
            "[UP/DOWN] Move    [ENTER] Toggle    [Type to Search]    [LEFT/RIGHT] Expand/Collapse    [CTRL+D] Clear All    [ESC] Back", gray);
    }
    if (footerText_.texture) {
        float x = (fw - footerText_.width) / 2.0f;
        SDL_FRect dst{x, fh - 35.0f, footerText_.width, footerText_.height};
        SDL_RenderTexture(renderer, footerText_.texture, nullptr, &dst);
    }
}