/*
    * filedialog.cpp
    * File open/save dialog implementation
    * Copyright (c) 2026 Daniel Hammer
*/

#include "filedialog.hpp"
#include "main.hpp"
#include <gui/svg.hpp>
#include <gui/canvas.hpp>
#include <gui/mtk/theme.hpp>
#include <gui/mtk/settings.hpp>
#include <gui/mtk/widgets.hpp>
#include <montauk/user.h>

extern "C" {
#include <stdio.h>
}

namespace {

using namespace gui;
using namespace filedialog;

constexpr const char* SPECIAL_FOLDER_NAMES[] = {
    "Documents", "Desktop", "Music", "Videos", "Pictures", "Downloads"
};
constexpr const char* SPECIAL_FOLDER_ICONS[] = {
    "folder-blue-documents.svg",
    "folder-blue-desktop.svg",
    "folder-blue-music.svg",
    "folder-blue-videos.svg",
    "folder-blue-pictures.svg",
    "folder-blue-downloads.svg"
};
constexpr int SPECIAL_FOLDER_COUNT = 6;

enum EntryType : uint8_t {
    ENTRY_FILE = 0,
    ENTRY_DIR = 1,
    ENTRY_DRIVE = 3,
    ENTRY_HOME = 4,
    ENTRY_SPECIAL = 7,
};

enum FocusField : uint8_t {
    FOCUS_LIST = 0,
    FOCUS_PATH = 1,
    FOCUS_NAME = 2,
};

struct FileDialogIcons {
    SvgIcon icon_go_back;
    SvgIcon icon_go_forward;
    SvgIcon icon_go_up;
    SvgIcon icon_home;
    SvgIcon icon_folder;
    SvgIcon icon_folder_lg;
    SvgIcon icon_file;
    SvgIcon icon_file_lg;
    SvgIcon icon_drive;
    SvgIcon icon_drive_lg;
    SvgIcon icon_home_folder;
    SvgIcon icon_home_folder_lg;
    SvgIcon icon_special[ SPECIAL_FOLDER_COUNT ];
    SvgIcon icon_special_lg[ SPECIAL_FOLDER_COUNT ];
};

struct FileDialogState {
    FileDialogIcons icons;

    char home_dir[256];
    char current_path[256];
    char history[MAX_HISTORY][256];
    int history_pos;
    int history_count;

    char entry_names[MAX_ENTRIES][64];
    uint8_t entry_types[MAX_ENTRIES];
    int entry_sizes[MAX_ENTRIES];
    bool is_dir[MAX_ENTRIES];
    int drive_indices[MAX_ENTRIES];
    int entry_count;

    int selected;
    int last_click_item;
    uint64_t last_click_time;

    Scrollbar scrollbar;
    bool grid_view;
    bool at_drives_root;
    FocusField focus;

    char path_buf[256];
    mtk::TextInputState path_input;

    char filename_buf[128];
    mtk::TextInputState filename_input;

    char pending_select[64];

    int mouse_x;
    int mouse_y;
};

FileDialogState g_file;

mtk::Theme file_theme() {
    return mtk::make_theme();
}

// File names may not contain path separators.
bool filename_char_filter(char ch, void*) {
    return ch != '/' && ch != '\\';
}

void safe_copy(char* dst, int dst_len, const char* src) {
    gui::dialogs::safe_copy(dst, dst_len, src);
}

int str_compare_ci(const char* a, const char* b) {
    while (*a && *b) {
        char ca = (*a >= 'A' && *a <= 'Z') ? (*a + 32) : *a;
        char cb = (*b >= 'A' && *b <= 'Z') ? (*b + 32) : *b;
        if (ca != cb) return ca - cb;
        a++;
        b++;
    }
    return (unsigned char)*a - (unsigned char)*b;
}

bool str_ends_with(const char* s, const char* suffix) {
    int slen = montauk::slen(s);
    int suflen = montauk::slen(suffix);
    if (suflen > slen) return false;
    for (int i = 0; i < suflen; i++) {
        char sc = s[slen - suflen + i];
        char ec = suffix[i];
        if (sc >= 'A' && sc <= 'Z') sc += 32;
        if (ec >= 'A' && ec <= 'Z') ec += 32;
        if (sc != ec) return false;
    }
    return true;
}

void str_append(char* dst, const char* src, int max_len) {
    int len = montauk::slen(dst);
    int i = 0;
    while (src[i] && len < max_len - 1) {
        dst[len++] = src[i++];
    }
    dst[len] = '\0';
}

const char* path_basename(const char* path) {
    const char* last = path;
    for (const char* p = path; *p; p++) {
        if (*p == '/' && *(p + 1)) last = p + 1;
    }
    return last;
}

void build_fullpath(char* out, int out_len, const char* dir, const char* name) {
    safe_copy(out, out_len, dir);
    int len = montauk::slen(out);
    if (len > 0 && out[len - 1] != '/') str_append(out, "/", out_len);
    str_append(out, name, out_len);
}

void split_parent_path(const char* path, char* out_dir, int out_dir_len, char* out_name, int out_name_len) {
    safe_copy(out_dir, out_dir_len, "");
    safe_copy(out_name, out_name_len, "");
    if (!path || !path[0]) return;

    int last_slash = -1;
    for (int i = 0; path[i]; i++)
        if (path[i] == '/') last_slash = i;

    if (last_slash < 0) {
        safe_copy(out_name, out_name_len, path);
        return;
    }

    int dir_len = last_slash + 1;
    if (dir_len >= out_dir_len) dir_len = out_dir_len - 1;
    montauk::memcpy(out_dir, path, (uint64_t)dir_len);
    out_dir[dir_len] = '\0';
    safe_copy(out_name, out_name_len, path + last_slash + 1);
}

bool is_dir_path(const char* path) {
    if (!path || !path[0]) return false;
    const char* names[1];
    return montauk::readdir(path, names, 1) >= 0;
}

bool path_exists_via_open(const char* path) {
    if (!path || !path[0]) return false;
    int fd = montauk::open(path);
    if (fd < 0) return false;
    montauk::close(fd);
    return true;
}

void format_size(char* buf, int buf_len, int size) {
    if (size < 1024) snprintf(buf, buf_len, "%d B", size);
    else if (size < 1024 * 1024) {
        int kb = size / 1024;
        int frac = ((size % 1024) * 10) / 1024;
        if (kb < 10) snprintf(buf, buf_len, "%d.%d KB", kb, frac);
        else snprintf(buf, buf_len, "%d KB", kb);
    } else {
        int mb = size / (1024 * 1024);
        int frac = ((size % (1024 * 1024)) * 10) / (1024 * 1024);
        if (mb < 10) snprintf(buf, buf_len, "%d.%d MB", mb, frac);
        else snprintf(buf, buf_len, "%d MB", mb);
    }
}

void fit_text_end(const char* src, char* out, int out_len, int max_px) {
    if (!src || !src[0]) {
        safe_copy(out, out_len, "");
        return;
    }
    if (text_width(src) <= max_px) {
        safe_copy(out, out_len, src);
        return;
    }

    int slen = montauk::slen(src);
    int keep = slen;
    while (keep > 1) {
        char candidate[256];
        candidate[0] = '.';
        candidate[1] = '.';
        int pos = 2;
        const char* tail = src + (slen - keep);
        while (*tail && pos < (int)sizeof(candidate) - 1)
            candidate[pos++] = *tail++;
        candidate[pos] = '\0';
        if (text_width(candidate) <= max_px) {
            safe_copy(out, out_len, candidate);
            return;
        }
        keep--;
    }

    safe_copy(out, out_len, src);
}

void fit_text_start(const char* src, char* out, int out_len, int max_px) {
    if (!src || !src[0] || out_len <= 0) {
        if (out_len > 0) out[0] = '\0';
        return;
    }
    if (text_width(src) <= max_px) {
        safe_copy(out, out_len, src);
        return;
    }

    // Grid labels must fit their cell in pixels. Character-count truncation is
    // insufficient for the proportional system font and lets wide names paint
    // over the adjacent label.
    int slen = montauk::slen(src);
    int keep = slen;
    if (keep > out_len - 3) keep = montauk::utf8::floor_boundary(src, slen, out_len - 3);
    while (keep > 0) {
        for (int i = 0; i < keep; i++) out[i] = src[i];
        out[keep] = '.';
        out[keep + 1] = '.';
        out[keep + 2] = '\0';
        if (text_width(out) <= max_px) return;
        keep = montauk::utf8::prev_boundary(src, keep);
    }

    safe_copy(out, out_len, "..");
}

// Path bar: the original plain white/square input look, but rendering the MTK
// text-input state so selection highlighting (and the right-click menu, drawn
// separately) keep working.
void draw_path_input(Canvas& c, const Rect& rect, const char* text,
                     const mtk::TextInputState& input, bool focused, const mtk::Theme& theme) {
    c.fill_rect(rect.x, rect.y, rect.w, rect.h, colors::WHITE);
    c.rect(rect.x, rect.y, rect.w, rect.h, focused ? colors::ACCENT : colors::BORDER);

    int fh = system_font_height();
    int tx = rect.x + 8;
    int ty = rect.y + (rect.h - fh) / 2;
    int len = mtk::text_input_len(text);

    if (focused && input.cursor != input.selection_anchor) {
        int cur = mtk::text_input_clamp_cursor(input.cursor, len);
        int anchor = mtk::text_input_clamp_cursor(input.selection_anchor, len);
        int start = cur < anchor ? cur : anchor;
        int end = cur > anchor ? cur : anchor;
        int sx = tx + mtk::text_input_prefix_width(text, start, false);
        int ex = tx + mtk::text_input_prefix_width(text, end, false);
        int clip_x = gui_max(sx, rect.x + 2);
        int clip_r = gui_min(ex, rect.x + rect.w - 2);
        if (clip_r > clip_x)
            c.fill_rect(clip_x, rect.y + 3, clip_r - clip_x, gui_max(rect.h - 6, 1), theme.text_selection);
    }

    c.text(tx, ty, text, colors::TEXT_COLOR);

    if (focused) {
        int cx = tx + mtk::text_input_prefix_width(text, gui_clamp(input.cursor, 0, len), false);
        c.vline(cx, rect.y + 4, rect.h - 8, colors::ACCENT);
    }
}

void draw_action_button(Canvas& c, const Rect& rect, const char* label, bool enabled, bool hovered, bool primary) {
    Color accent = gui::mtk::load_system_accent();
    Color bg = primary ? accent : Color::from_rgb(0xE8, 0xE8, 0xE8);
    Color fg = primary ? colors::WHITE : colors::TEXT_COLOR;
    if (!enabled) {
        bg = Color::from_rgb(0xF0, 0xF0, 0xF0);
        fg = Color::from_rgb(0x9A, 0x9A, 0x9A);
    } else if (hovered) {
        bg = primary ? gui::mtk::darken(accent, 32) : Color::from_rgb(0xDC, 0xDC, 0xDC);
    }
    c.fill_rounded_rect(rect.x, rect.y, rect.w, rect.h, 4, bg);
    int tx = rect.x + (rect.w - text_width(label)) / 2;
    int ty = rect.y + (rect.h - system_font_height()) / 2;
    c.text(tx, ty, label, fg);
}

void draw_scrollbar(Canvas& c, const Scrollbar& sb) {
    if (sb.content_height <= sb.view_height) return;
    c.fill_rect(sb.bounds.x, sb.bounds.y, sb.bounds.w, sb.bounds.h, sb.bg);
    int th = sb.thumb_height();
    int ty = sb.thumb_y();
    Color thumb = (sb.hovered || sb.dragging) ? sb.hover_fg : sb.fg;
    c.fill_rounded_rect(sb.bounds.x + 1, ty, sb.bounds.w - 2, th, 3, thumb);
}

FileDialogLayout file_layout(const FileDialogState* st) {
    FileDialogLayout lo = {};
    int footer_h = (g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE) ? FOOTER_H_SAVE : FOOTER_H_OPEN;
    lo.back_btn = {4, 4, 24, 24};
    lo.forward_btn = {32, 4, 24, 24};
    lo.up_btn = {60, 4, 24, 24};
    lo.home_btn = {88, 4, 24, 24};
    lo.view_btn = {120, 4, 24, 24};
    lo.path_rect = {8, TOOLBAR_H + 4, g_app.win.width - 16, PATHBAR_H - 8};
    lo.content_rect = {0, TOOLBAR_H + PATHBAR_H, g_app.win.width, g_app.win.height - TOOLBAR_H - PATHBAR_H - footer_h};
    lo.footer_rect = {0, g_app.win.height - footer_h, g_app.win.width, footer_h};
    lo.list_rect = lo.content_rect;
    int btn_y = (g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE)
        ? lo.footer_rect.y + 12
        : lo.footer_rect.y + (footer_h - BUTTON_H) / 2;
    lo.confirm_btn = {g_app.win.width - BUTTON_W - 8, btn_y, BUTTON_W, BUTTON_H};
    lo.cancel_btn = {lo.confirm_btn.x - BUTTON_W - 8, btn_y, BUTTON_W, BUTTON_H};
    lo.name_rect = {88, lo.footer_rect.y + 12, lo.cancel_btn.x - 100, 30};
    if (lo.name_rect.w < 120) lo.name_rect.w = 120;
    (void)st;
    return lo;
}

void file_sync_path_buffer(FileDialogState* st) {
    if (st->at_drives_root) {
        st->path_buf[0] = '\0';
        mtk::text_input_reset(st->path_input, 0);
        return;
    }
    safe_copy(st->path_buf, sizeof(st->path_buf), st->current_path);
    mtk::text_input_reset(st->path_input, montauk::slen(st->path_buf));
}

void file_set_filename(FileDialogState* st, const char* name) {
    safe_copy(st->filename_buf, sizeof(st->filename_buf), name);
    mtk::text_input_reset(st->filename_input, montauk::slen(st->filename_buf));
}

int special_folder_index(const char* name) {
    for (int i = 0; i < SPECIAL_FOLDER_COUNT; i++) {
        if (montauk::streq(name, SPECIAL_FOLDER_NAMES[i])) return i;
    }
    return -1;
}

void load_file_icons(FileDialogState* st) {
    Color def = colors::ICON_COLOR;
    st->icons.icon_go_back = svg_load("0:/os/icons/go-previous-symbolic.svg", 16, 16, def);
    st->icons.icon_go_forward = svg_load("0:/os/icons/go-next-symbolic.svg", 16, 16, def);
    st->icons.icon_go_up = svg_load("0:/os/icons/go-up-symbolic.svg", 16, 16, def);
    st->icons.icon_home = svg_load("0:/os/icons/user-home.svg", 16, 16, def);
    st->icons.icon_folder = svg_load("0:/os/icons/folder.svg", 16, 16, def);
    st->icons.icon_folder_lg = svg_load("0:/os/icons/folder.svg", 48, 48, def);
    st->icons.icon_file = svg_load("0:/os/icons/text-x-generic.svg", 16, 16, def);
    st->icons.icon_file_lg = svg_load("0:/os/icons/text-x-generic.svg", 48, 48, def);
    st->icons.icon_drive = svg_load("0:/os/icons/drive-harddisk.svg", 16, 16, def);
    st->icons.icon_drive_lg = svg_load("0:/os/icons/drive-harddisk.svg", 48, 48, def);
    st->icons.icon_home_folder = svg_load("0:/os/icons/folder-blue-home.svg", 16, 16, def);
    st->icons.icon_home_folder_lg = svg_load("0:/os/icons/folder-blue-home.svg", 48, 48, def);
    for (int i = 0; i < SPECIAL_FOLDER_COUNT; i++) {
        char path[128];
        snprintf(path, sizeof(path), "0:/os/icons/%s", SPECIAL_FOLDER_ICONS[i]);
        st->icons.icon_special[i] = svg_load(path, 16, 16, def);
        st->icons.icon_special_lg[i] = svg_load(path, 48, 48, def);
    }
}

void free_icon(SvgIcon* icon) {
    if (icon && icon->pixels) {
        svg_free(*icon);
        icon->pixels = nullptr;
    }
}

void free_file_icons(FileDialogState* st) {
    free_icon(&st->icons.icon_go_back);
    free_icon(&st->icons.icon_go_forward);
    free_icon(&st->icons.icon_go_up);
    free_icon(&st->icons.icon_home);
    free_icon(&st->icons.icon_folder);
    free_icon(&st->icons.icon_folder_lg);
    free_icon(&st->icons.icon_file);
    free_icon(&st->icons.icon_file_lg);
    free_icon(&st->icons.icon_drive);
    free_icon(&st->icons.icon_drive_lg);
    free_icon(&st->icons.icon_home_folder);
    free_icon(&st->icons.icon_home_folder_lg);
    for (int i = 0; i < SPECIAL_FOLDER_COUNT; i++) {
        free_icon(&st->icons.icon_special[i]);
        free_icon(&st->icons.icon_special_lg[i]);
    }
}

void file_push_history(FileDialogState* st) {
    if (st->history_count > 0 && st->history_pos >= 0) {
        if (montauk::streq(st->history[st->history_pos], st->current_path)) return;
    }
    st->history_pos++;
    if (st->history_pos >= MAX_HISTORY) {
        for (int i = 1; i < MAX_HISTORY; i++)
            safe_copy(st->history[i - 1], sizeof(st->history[i - 1]), st->history[i]);
        st->history_pos = MAX_HISTORY - 1;
    }
    safe_copy(st->history[st->history_pos], sizeof(st->history[st->history_pos]), st->current_path);
    st->history_count = st->history_pos + 1;
}

void file_apply_pending_select(FileDialogState* st) {
    st->selected = -1;
    if (!st->pending_select[0]) return;
    for (int i = 0; i < st->entry_count; i++) {
        if (montauk::streq(st->entry_names[i], st->pending_select)) {
            st->selected = i;
            break;
        }
    }
    st->pending_select[0] = '\0';
}

void file_read_drives(FileDialogState* st) {
    st->entry_count = 0;
    st->at_drives_root = true;
    st->current_path[0] = '\0';

    if (st->home_dir[0] != '\0') {
        int i = st->entry_count++;
        safe_copy(st->entry_names[i], sizeof(st->entry_names[i]), "Home");
        st->entry_types[i] = ENTRY_HOME;
        st->entry_sizes[i] = 0;
        st->is_dir[i] = true;
        st->drive_indices[i] = -1;
    }

    if (st->home_dir[0] != '\0') {
        for (int sf = 0; sf < SPECIAL_FOLDER_COUNT && st->entry_count < MAX_ENTRIES; sf++) {
            char probe[256];
            safe_copy(probe, sizeof(probe), st->home_dir);
            int plen = montauk::slen(probe);
            if (plen > 0 && probe[plen - 1] != '/') str_append(probe, "/", sizeof(probe));
            str_append(probe, SPECIAL_FOLDER_NAMES[sf], sizeof(probe));
            if (path_exists_via_open(probe)) {
                int i = st->entry_count++;
                safe_copy(st->entry_names[i], sizeof(st->entry_names[i]), SPECIAL_FOLDER_NAMES[sf]);
                st->entry_types[i] = ENTRY_SPECIAL;
                st->entry_sizes[i] = 0;
                st->is_dir[i] = true;
                st->drive_indices[i] = sf;
            }
        }
    }

    int drives[MAX_DRIVES];
    int drive_count = montauk::drivelist(drives, MAX_DRIVES);
    for (int di = 0; di < drive_count && st->entry_count < MAX_ENTRIES; di++) {
        int d = drives[di];
        int i = st->entry_count++;
        char label[64];
        if (d < 10) snprintf(label, sizeof(label), "Drive %d:/", d);
        else snprintf(label, sizeof(label), "Drive %d:/", d);
        safe_copy(st->entry_names[i], sizeof(st->entry_names[i]), label);
        st->entry_types[i] = ENTRY_DRIVE;
        st->entry_sizes[i] = 0;
        st->is_dir[i] = true;
        st->drive_indices[i] = d;
    }

    st->scrollbar.scroll_offset = 0;
    st->last_click_item = -1;
    st->last_click_time = 0;
    file_sync_path_buffer(st);
    file_apply_pending_select(st);
}

void file_read_dir(FileDialogState* st) {
    if (!st->current_path[0] || !is_dir_path(st->current_path)) {
        file_read_drives(st);
        return;
    }

    st->at_drives_root = false;
    const char* names[MAX_ENTRIES];
    st->entry_count = montauk::readdir(st->current_path, names, MAX_ENTRIES);
    if (st->entry_count < 0) st->entry_count = 0;

    const char* after_drive = st->current_path;
    for (int k = 0; after_drive[k]; k++) {
        if (after_drive[k] == ':' && after_drive[k + 1] == '/') {
            after_drive += k + 2;
            break;
        }
    }

    char prefix[256] = {};
    int prefix_len = 0;
    if (after_drive[0] != '\0') {
        safe_copy(prefix, sizeof(prefix), after_drive);
        prefix_len = montauk::slen(prefix);
        if (prefix_len > 0 && prefix[prefix_len - 1] != '/') {
            prefix[prefix_len++] = '/';
            prefix[prefix_len] = '\0';
        }
    }

    for (int i = 0; i < st->entry_count; i++) {
        const char* raw = names[i];
        if (prefix_len > 0) {
            bool match = true;
            for (int k = 0; k < prefix_len; k++) {
                if (raw[k] != prefix[k]) { match = false; break; }
            }
            if (match) raw += prefix_len;
        }

        safe_copy(st->entry_names[i], sizeof(st->entry_names[i]), raw);
        int len = montauk::slen(st->entry_names[i]);
        if (len > 0 && st->entry_names[i][len - 1] == '/') {
            st->is_dir[i] = true;
            st->entry_names[i][len - 1] = '\0';
        } else {
            st->is_dir[i] = false;
        }

        st->entry_types[i] = st->is_dir[i] ? ENTRY_DIR : ENTRY_FILE;
        st->entry_sizes[i] = 0;
        st->drive_indices[i] = -1;

        if (!st->is_dir[i]) {
            char full[512];
            build_fullpath(full, sizeof(full), st->current_path, st->entry_names[i]);
            int fd = montauk::open(full);
            if (fd >= 0) {
                st->entry_sizes[i] = (int)montauk::getsize(fd);
                montauk::close(fd);
            }
        }
    }

    for (int i = 1; i < st->entry_count; i++) {
        char tmp_name[64];
        uint8_t tmp_type = st->entry_types[i];
        int tmp_size = st->entry_sizes[i];
        bool tmp_isdir = st->is_dir[i];
        safe_copy(tmp_name, sizeof(tmp_name), st->entry_names[i]);

        int j = i - 1;
        while (j >= 0) {
            bool swap = false;
            if (tmp_isdir && !st->is_dir[j]) swap = true;
            else if (tmp_isdir == st->is_dir[j] && str_compare_ci(tmp_name, st->entry_names[j]) < 0) swap = true;
            if (!swap) break;

            safe_copy(st->entry_names[j + 1], sizeof(st->entry_names[j + 1]), st->entry_names[j]);
            st->entry_types[j + 1] = st->entry_types[j];
            st->entry_sizes[j + 1] = st->entry_sizes[j];
            st->is_dir[j + 1] = st->is_dir[j];
            st->drive_indices[j + 1] = st->drive_indices[j];
            j--;

            safe_copy(st->entry_names[j + 1], sizeof(st->entry_names[j + 1]), tmp_name);
            st->entry_types[j + 1] = tmp_type;
            st->entry_sizes[j + 1] = tmp_size;
            st->is_dir[j + 1] = tmp_isdir;
            st->drive_indices[j + 1] = -1;
        }
    }

    st->scrollbar.scroll_offset = 0;
    st->last_click_item = -1;
    st->last_click_time = 0;
    file_sync_path_buffer(st);
    file_apply_pending_select(st);
}

void file_ensure_selected_visible(FileDialogState* st) {
    if (st->selected < 0 || st->selected >= st->entry_count) return;
    FileDialogLayout lo = file_layout(st);
    if (st->grid_view) {
        int cols = (lo.content_rect.w - SCROLLBAR_W) / GRID_CELL_W;
        if (cols < 1) cols = 1;
        int row = st->selected / cols;
        int top = row * GRID_CELL_H;
        int bottom = top + GRID_CELL_H;
        if (top < st->scrollbar.scroll_offset) st->scrollbar.scroll_offset = top;
        else if (bottom > st->scrollbar.scroll_offset + lo.content_rect.h)
            st->scrollbar.scroll_offset = bottom - lo.content_rect.h;
    } else {
        int view_h = lo.content_rect.h - HEADER_H;
        int top = st->selected * ITEM_H;
        int bottom = top + ITEM_H;
        if (top < st->scrollbar.scroll_offset) st->scrollbar.scroll_offset = top;
        else if (bottom > st->scrollbar.scroll_offset + view_h)
            st->scrollbar.scroll_offset = bottom - view_h;
    }
    int ms = st->scrollbar.max_scroll();
    if (st->scrollbar.scroll_offset < 0) st->scrollbar.scroll_offset = 0;
    if (st->scrollbar.scroll_offset > ms) st->scrollbar.scroll_offset = ms;
}

void file_navigate_into(FileDialogState* st, int idx) {
    if (idx < 0 || idx >= st->entry_count) return;

    if (st->at_drives_root && st->entry_types[idx] == ENTRY_HOME) {
        safe_copy(st->current_path, sizeof(st->current_path), st->home_dir);
        file_push_history(st);
        file_read_dir(st);
        return;
    }

    if (st->at_drives_root && st->entry_types[idx] == ENTRY_SPECIAL) {
        safe_copy(st->current_path, sizeof(st->current_path), st->home_dir);
        int len = montauk::slen(st->current_path);
        if (len > 0 && st->current_path[len - 1] != '/') str_append(st->current_path, "/", sizeof(st->current_path));
        str_append(st->current_path, st->entry_names[idx], sizeof(st->current_path));
        file_push_history(st);
        file_read_dir(st);
        return;
    }

    if (st->at_drives_root && st->entry_types[idx] == ENTRY_DRIVE) {
        snprintf(st->current_path, sizeof(st->current_path), "%d:/", st->drive_indices[idx]);
        file_push_history(st);
        file_read_dir(st);
        return;
    }

    if (st->is_dir[idx]) {
        char next[256];
        build_fullpath(next, sizeof(next), st->current_path, st->entry_names[idx]);
        safe_copy(st->current_path, sizeof(st->current_path), next);
        file_push_history(st);
        file_read_dir(st);
    }
}

bool file_accept_open(FileDialogState* st) {
    if (st->selected < 0 || st->selected >= st->entry_count) return false;
    if (st->is_dir[st->selected]) {
        file_navigate_into(st, st->selected);
        return false;
    }

    char full[512];
    build_fullpath(full, sizeof(full), st->current_path, st->entry_names[st->selected]);
    dialog_finish("ok", full, "", full);
    return true;
}

bool file_accept_save(FileDialogState* st) {
    if (st->at_drives_root) return false;
    if (!st->filename_buf[0]) return false;

    char full[512];
    build_fullpath(full, sizeof(full), st->current_path, st->filename_buf);
    dialog_finish("ok", full, "", full);
    return true;
}

void file_activate_selected(FileDialogState* st, bool from_double_click) {
    if (st->selected < 0 || st->selected >= st->entry_count) return;
    if (st->is_dir[st->selected]) {
        file_navigate_into(st, st->selected);
        return;
    }

    if (g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE) {
        file_set_filename(st, st->entry_names[st->selected]);
        if (from_double_click) file_accept_save(st);
    } else {
        file_accept_open(st);
    }
}

void file_go_home(FileDialogState* st) {
    if (st->home_dir[0] && is_dir_path(st->home_dir)) {
        safe_copy(st->current_path, sizeof(st->current_path), st->home_dir);
        file_read_dir(st);
        file_push_history(st);
        return;
    }
    file_read_drives(st);
    file_push_history(st);
}

void file_go_back(FileDialogState* st) {
    if (st->history_pos <= 0) return;
    st->history_pos--;
    safe_copy(st->current_path, sizeof(st->current_path), st->history[st->history_pos]);
    if (st->current_path[0]) file_read_dir(st);
    else file_read_drives(st);
}

void file_go_forward(FileDialogState* st) {
    if (st->history_pos >= st->history_count - 1) return;
    st->history_pos++;
    safe_copy(st->current_path, sizeof(st->current_path), st->history[st->history_pos]);
    if (st->current_path[0]) file_read_dir(st);
    else file_read_drives(st);
}

void file_go_up(FileDialogState* st) {
    if (st->at_drives_root) return;

    int len = montauk::slen(st->current_path);
    if (len >= 3 && st->current_path[len - 1] == '/') {
        int colon = -1;
        for (int i = 0; i < len; i++) {
            if (st->current_path[i] == ':') { colon = i; break; }
        }
        if (colon >= 0 && colon + 2 == len) {
            file_read_drives(st);
            file_push_history(st);
            return;
        }
    }

    if (len > 0 && st->current_path[len - 1] == '/') {
        st->current_path[len - 1] = '\0';
        len--;
    }
    int last_slash = -1;
    for (int i = len - 1; i >= 0; i--) {
        if (st->current_path[i] == '/') { last_slash = i; break; }
    }
    if (last_slash >= 0) {
        if (last_slash > 0 && st->current_path[last_slash - 1] == ':') st->current_path[last_slash + 1] = '\0';
        else st->current_path[last_slash] = '\0';
    }
    file_push_history(st);
    file_read_dir(st);
}

void file_open_path(FileDialogState* st, const char* path) {
    if (!path || !path[0]) {
        if (st->home_dir[0]) {
            safe_copy(st->current_path, sizeof(st->current_path), st->home_dir);
            file_push_history(st);
            file_read_dir(st);
        } else {
            file_read_drives(st);
            file_push_history(st);
        }
        return;
    }

    if (is_dir_path(path)) {
        safe_copy(st->current_path, sizeof(st->current_path), path);
        file_push_history(st);
        file_read_dir(st);
        return;
    }

    char dir[256];
    char name[128];
    split_parent_path(path, dir, sizeof(dir), name, sizeof(name));
    if (dir[0] && is_dir_path(dir)) {
        safe_copy(st->current_path, sizeof(st->current_path), dir);
        safe_copy(st->pending_select, sizeof(st->pending_select), name);
        if (g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE && name[0]) file_set_filename(st, name);
        file_push_history(st);
        file_read_dir(st);
        if (g_app.request.mode == gui::dialogs::FILE_DIALOG_OPEN && name[0]) {
            for (int i = 0; i < st->entry_count; i++) {
                if (montauk::streq(st->entry_names[i], name)) {
                    st->selected = i;
                    break;
                }
            }
        }
        return;
    }
}

void init_file_dialog(const gui::dialogs::Request& req) {
    FileDialogState* st = &g_file;
    montauk::memset(st, 0, sizeof(*st));
    load_file_icons(st);
    st->selected = -1;
    st->last_click_item = -1;
    st->history_pos = -1;
    st->grid_view = true;
    st->focus = FOCUS_LIST;
    st->scrollbar.init(0, 0, SCROLLBAR_W, 100);
    montauk::user::get_home_dir(st->home_dir, sizeof(st->home_dir));

    char initial_dir[256] = {};
    char initial_name[128] = {};
    if (req.initial_path[0]) split_parent_path(req.initial_path, initial_dir, sizeof(initial_dir), initial_name, sizeof(initial_name));

    if (req.initial_path[0] && is_dir_path(req.initial_path)) {
        safe_copy(st->current_path, sizeof(st->current_path), req.initial_path);
        file_read_dir(st);
        file_push_history(st);
    } else if (initial_dir[0] && is_dir_path(initial_dir)) {
        safe_copy(st->current_path, sizeof(st->current_path), initial_dir);
        safe_copy(st->pending_select, sizeof(st->pending_select), initial_name);
        file_read_dir(st);
        file_push_history(st);
    } else if (st->home_dir[0] && is_dir_path(st->home_dir)) {
        safe_copy(st->current_path, sizeof(st->current_path), st->home_dir);
        file_read_dir(st);
        file_push_history(st);
    } else {
        file_read_drives(st);
        file_push_history(st);
    }

    if (req.mode == gui::dialogs::FILE_DIALOG_SAVE) {
        if (req.suggested_name[0]) file_set_filename(st, req.suggested_name);
        else if (initial_name[0]) file_set_filename(st, initial_name);
    }
}

void draw_toolbar_icon(Canvas& c, const Rect& rect, const SvgIcon& icon) {
    c.fill_rect(rect.x, rect.y, rect.w, rect.h, Color::from_rgb(0xE8, 0xE8, 0xE8));
    if (icon.pixels) {
        int ix = rect.x + (rect.w - icon.width) / 2;
        int iy = rect.y + (rect.h - icon.height) / 2;
        c.icon(ix, iy, icon);
    }
}

void draw_grid_entries(Canvas& c, FileDialogState* st, const FileDialogLayout& lo) {
    int cols = (lo.content_rect.w - SCROLLBAR_W) / GRID_CELL_W;
    if (cols < 1) cols = 1;
    int rows = (st->entry_count + cols - 1) / cols;
    int content_h = rows * GRID_CELL_H;
    st->scrollbar.bounds = {c.w - SCROLLBAR_W, lo.content_rect.y, SCROLLBAR_W, lo.content_rect.h};
    st->scrollbar.content_height = content_h;
    st->scrollbar.view_height = lo.content_rect.h;

    Color sel_bg = gui::mtk::accent_hover_tint(gui::mtk::load_system_accent());

    for (int i = 0; i < st->entry_count; i++) {
        int col = i % cols;
        int row = i / cols;
        int cell_x = col * GRID_CELL_W;
        int cell_y = lo.content_rect.y + row * GRID_CELL_H - st->scrollbar.scroll_offset;
        if (cell_y + GRID_CELL_H <= lo.content_rect.y || cell_y >= lo.content_rect.y + lo.content_rect.h) continue;

        if (i == st->selected) {
            int sy = gui_max(cell_y, lo.content_rect.y);
            int sh = gui_min(cell_y + GRID_CELL_H, lo.content_rect.y + lo.content_rect.h) - sy;
            int sw = gui_min(GRID_CELL_W, c.w - SCROLLBAR_W - cell_x);
            if (sh > 0 && sw > 0) c.fill_rect(cell_x, sy, sw, sh, sel_bg);
        }

        int icon_x = cell_x + (GRID_CELL_W - GRID_ICON) / 2;
        int icon_y = cell_y + GRID_PAD;
        SvgIcon* icon = &st->icons.icon_file_lg;
        int sfi = -1;
        if (st->entry_types[i] == ENTRY_SPECIAL) sfi = st->drive_indices[i];
        if (sfi >= 0 && st->icons.icon_special_lg[sfi].pixels) icon = &st->icons.icon_special_lg[sfi];
        else if (st->entry_types[i] == ENTRY_HOME && st->icons.icon_home_folder_lg.pixels) icon = &st->icons.icon_home_folder_lg;
        else if (st->entry_types[i] == ENTRY_DRIVE && st->icons.icon_drive_lg.pixels) icon = &st->icons.icon_drive_lg;
        else if (st->is_dir[i] && st->icons.icon_folder_lg.pixels) icon = &st->icons.icon_folder_lg;
        if (icon->pixels) c.icon(icon_x, icon_y, *icon);

        char label[64];
        fit_text_start(st->entry_names[i], label, sizeof(label), GRID_CELL_W - 4);
        int tx = cell_x + (GRID_CELL_W - text_width(label)) / 2;
        if (tx < cell_x + 2) tx = cell_x + 2;
        int ty = icon_y + GRID_ICON + 2;
        if (ty >= lo.content_rect.y && ty + system_font_height() <= lo.content_rect.y + lo.content_rect.h)
            c.text(tx, ty, label, colors::TEXT_COLOR);
    }
}

void draw_list_entries(Canvas& c, FileDialogState* st, const FileDialogLayout& lo) {
    int header_y = lo.content_rect.y;
    int rows_y = header_y + HEADER_H;
    int rows_h = lo.content_rect.h - HEADER_H;
    if (rows_h < 0) rows_h = 0;

    c.fill_rect(0, header_y, c.w, HEADER_H, Color::from_rgb(0xF8, 0xF8, 0xF8));
    c.text(8, header_y + 2, "Name", Color::from_rgb(0x88, 0x88, 0x88));
    c.text(c.w - SCROLLBAR_W - 120, header_y + 2, "Size", Color::from_rgb(0x88, 0x88, 0x88));
    c.text(c.w - SCROLLBAR_W - 60, header_y + 2, "Type", Color::from_rgb(0x88, 0x88, 0x88));
    c.hline(0, header_y + HEADER_H - 1, c.w, colors::BORDER);
    c.vline(c.w - SCROLLBAR_W - 124, header_y, lo.content_rect.h, colors::BORDER);
    c.vline(c.w - SCROLLBAR_W - 64, header_y, lo.content_rect.h, colors::BORDER);

    st->scrollbar.bounds = {c.w - SCROLLBAR_W, rows_y, SCROLLBAR_W, rows_h};
    st->scrollbar.content_height = st->entry_count * ITEM_H;
    st->scrollbar.view_height = rows_h;

    Color sel_bg = gui::mtk::accent_hover_tint(gui::mtk::load_system_accent());

    for (int i = 0; i < st->entry_count; i++) {
        int y = rows_y + i * ITEM_H - st->scrollbar.scroll_offset;
        if (y + ITEM_H <= rows_y || y >= rows_y + rows_h) continue;

        if (i == st->selected) c.fill_rect(0, y, c.w - SCROLLBAR_W, ITEM_H, sel_bg);

        int sfi = -1;
        if (st->entry_types[i] == ENTRY_SPECIAL) sfi = st->drive_indices[i];
        if (sfi >= 0 && st->icons.icon_special[sfi].pixels) c.icon(8, y + 4, st->icons.icon_special[sfi]);
        else if (st->entry_types[i] == ENTRY_HOME && st->icons.icon_home_folder.pixels) c.icon(8, y + 4, st->icons.icon_home_folder);
        else if (st->entry_types[i] == ENTRY_DRIVE && st->icons.icon_drive.pixels) c.icon(8, y + 4, st->icons.icon_drive);
        else if (st->is_dir[i] && st->icons.icon_folder.pixels) c.icon(8, y + 4, st->icons.icon_folder);
        else if (st->icons.icon_file.pixels) c.icon(8, y + 4, st->icons.icon_file);

        c.text(30, y + 3, st->entry_names[i], colors::TEXT_COLOR);

        if (!st->is_dir[i]) {
            char size_buf[16];
            format_size(size_buf, sizeof(size_buf), st->entry_sizes[i]);
            c.text(c.w - SCROLLBAR_W - 120, y + 3, size_buf, Color::from_rgb(0x66, 0x66, 0x66));
        }

        const char* type_label = st->is_dir[i] ? "Folder" : "File";
        if (st->entry_types[i] == ENTRY_DRIVE) type_label = "Drive";
        else if (st->entry_types[i] == ENTRY_HOME) type_label = "Home";
        c.text(c.w - SCROLLBAR_W - 60, y + 3, type_label, Color::from_rgb(0x66, 0x66, 0x66));
        c.hline(0, y + ITEM_H - 1, c.w, Color::from_rgb(0xF0, 0xF0, 0xF0));
    }
}

void draw_file_dialog() {
    FileDialogState* st = &g_file;
    Canvas c = g_app.win.canvas();
    c.fill(colors::WINDOW_BG);

    mtk::Theme theme = file_theme();
    bool save_mode = g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE;
    FileDialogLayout lo = file_layout(st);

    c.fill_rect(0, 0, c.w, TOOLBAR_H, Color::from_rgb(0xF5, 0xF5, 0xF5));
    draw_toolbar_icon(c, lo.back_btn, st->icons.icon_go_back);
    draw_toolbar_icon(c, lo.forward_btn, st->icons.icon_go_forward);
    draw_toolbar_icon(c, lo.up_btn, st->icons.icon_go_up);
    draw_toolbar_icon(c, lo.home_btn, st->icons.icon_home);

    c.fill_rect(lo.view_btn.x, lo.view_btn.y, lo.view_btn.w, lo.view_btn.h, Color::from_rgb(0xE8, 0xE8, 0xE8));
    if (st->grid_view) {
        for (int r = 0; r < 2; r++)
            for (int cc = 0; cc < 2; cc++)
                c.fill_rect(lo.view_btn.x + 5 + cc * 8, lo.view_btn.y + 5 + r * 8, 6, 6, colors::TEXT_COLOR);
    } else {
        for (int r = 0; r < 3; r++)
            c.fill_rect(lo.view_btn.x + 5, lo.view_btn.y + 5 + r * 5, 14, 2, colors::TEXT_COLOR);
    }
    c.hline(0, TOOLBAR_H - 1, c.w, colors::BORDER);

    bool path_focused = st->focus == FOCUS_PATH;
    const char* path_text = (st->at_drives_root && !path_focused && !st->path_buf[0])
                                ? "Computer" : st->path_buf;
    draw_path_input(c, lo.path_rect, path_text, st->path_input, path_focused, theme);

    if (st->grid_view) draw_grid_entries(c, st, lo);
    else draw_list_entries(c, st, lo);

    draw_scrollbar(c, st->scrollbar);

    c.fill_rect(0, lo.footer_rect.y, c.w, lo.footer_rect.h, Color::from_rgb(0xF7, 0xF7, 0xF7));
    c.hline(0, lo.footer_rect.y, c.w, colors::BORDER);

    bool confirm_enabled = false;
    const char* confirm_label = save_mode ? "Save" : "Open";
    if (save_mode) {
        c.text(12, lo.footer_rect.y + 18, "File name", Color::from_rgb(0x66, 0x66, 0x66));
        mtk::draw_text_field(c, lo.name_rect, st->filename_buf, st->filename_input.cursor,
                             st->focus == FOCUS_NAME, false, theme,
                             st->filename_input.selection_anchor);
        confirm_enabled = st->filename_buf[0] != '\0' && !st->at_drives_root;
    } else {
        char selection[256] = {};
        if (st->selected >= 0 && st->selected < st->entry_count) {
            char full[512];
            if (st->at_drives_root && st->entry_types[st->selected] == ENTRY_HOME) safe_copy(full, sizeof(full), st->home_dir);
            else if (st->at_drives_root && st->entry_types[st->selected] == ENTRY_DRIVE) snprintf(full, sizeof(full), "%d:/", st->drive_indices[st->selected]);
            else if (st->at_drives_root && st->entry_types[st->selected] == ENTRY_SPECIAL) {
                safe_copy(full, sizeof(full), st->home_dir);
                int len = montauk::slen(full);
                if (len > 0 && full[len - 1] != '/') str_append(full, "/", sizeof(full));
                str_append(full, st->entry_names[st->selected], sizeof(full));
            } else {
                build_fullpath(full, sizeof(full), st->current_path, st->entry_names[st->selected]);
            }
            fit_text_end(full, selection, sizeof(selection), lo.cancel_btn.x - 16);
        } else {
            safe_copy(selection, sizeof(selection), "Choose a file");
        }
        c.text(12, lo.footer_rect.y + 14, selection, Color::from_rgb(0x66, 0x66, 0x66));
        confirm_enabled = st->selected >= 0;
    }

    draw_action_button(c, lo.cancel_btn, "Cancel", true, lo.cancel_btn.contains(st->mouse_x, st->mouse_y), false);
    draw_action_button(c, lo.confirm_btn, confirm_label, confirm_enabled, lo.confirm_btn.contains(st->mouse_x, st->mouse_y), true);

    // Text-field context menus draw last so they overlay every other element.
    mtk::draw_text_input_context_menu(
        c, st->path_input, theme,
        mtk::text_input_has_selection(st->path_input, st->path_buf, (int)sizeof(st->path_buf)));
    if (save_mode) {
        mtk::draw_text_input_context_menu(
            c, st->filename_input, theme,
            mtk::text_input_has_selection(st->filename_input, st->filename_buf,
                                          (int)sizeof(st->filename_buf)));
    }
}

int file_entry_at(FileDialogState* st, int mx, int my) {
    FileDialogLayout lo = file_layout(st);
    if (!lo.content_rect.contains(mx, my)) return -1;

    if (st->grid_view) {
        if (mx >= lo.content_rect.w - SCROLLBAR_W) return -1;
        int cols = (lo.content_rect.w - SCROLLBAR_W) / GRID_CELL_W;
        if (cols < 1) cols = 1;
        int col = mx / GRID_CELL_W;
        int row = (my - lo.content_rect.y + st->scrollbar.scroll_offset) / GRID_CELL_H;
        int idx = row * cols + col;
        if (idx >= 0 && idx < st->entry_count && col < cols) return idx;
        return -1;
    }

    int rows_y = lo.content_rect.y + HEADER_H;
    if (my < rows_y || mx >= lo.content_rect.w - SCROLLBAR_W) return -1;
    int rel_y = my - rows_y + st->scrollbar.scroll_offset;
    int idx = rel_y / ITEM_H;
    if (idx >= 0 && idx < st->entry_count) return idx;
    return -1;
}

int file_field_mouse(mtk::TextInputState& input, const Rect& rect, char* buf, int cap,
                     const MouseEvent& me, bool focused, mtk::TextInputCharFilter filter) {
    return mtk::text_input_handle_mouse(input, rect, buf, cap,
                                        me.x, me.y, me.buttons, me.prev_buttons,
                                        g_app.win.width, g_app.win.height,
                                        focused, false, filter);
}

void handle_file_mouse(const montauk::abi::WinEvent& ev) {
    FileDialogState* st = &g_file;
    st->mouse_x = ev.mouse.x;
    st->mouse_y = ev.mouse.y;

    FileDialogLayout lo = file_layout(st);
    MouseEvent me = {ev.mouse.x, ev.mouse.y, ev.mouse.buttons, ev.mouse.prev_buttons, ev.mouse.scroll};
    bool save_mode = g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE;

    // While a text field owns the interaction (an open context menu or an
    // in-progress drag-selection), route all mouse input to it first.
    if (st->path_input.context.open || st->path_input.dragging) {
        if (file_field_mouse(st->path_input, lo.path_rect, st->path_buf, (int)sizeof(st->path_buf),
                             me, st->focus == FOCUS_PATH, nullptr) != mtk::TEXT_INPUT_NONE)
            return;
    }
    if (save_mode && (st->filename_input.context.open || st->filename_input.dragging)) {
        if (file_field_mouse(st->filename_input, lo.name_rect, st->filename_buf,
                             (int)sizeof(st->filename_buf), me, st->focus == FOCUS_NAME,
                             filename_char_filter) != mtk::TEXT_INPUT_NONE)
            return;
    }

    st->scrollbar.handle_mouse(me);

    // Right-click inside a field opens its Cut/Copy/Paste/Delete menu.
    if (me.right_pressed()) {
        if (lo.path_rect.contains(me.x, me.y)) {
            st->focus = FOCUS_PATH;
            if (save_mode) mtk::context_menu_close(st->filename_input.context);
            file_field_mouse(st->path_input, lo.path_rect, st->path_buf, (int)sizeof(st->path_buf),
                             me, true, nullptr);
            return;
        }
        if (save_mode && lo.name_rect.contains(me.x, me.y)) {
            st->focus = FOCUS_NAME;
            mtk::context_menu_close(st->path_input.context);
            file_field_mouse(st->filename_input, lo.name_rect, st->filename_buf,
                             (int)sizeof(st->filename_buf), me, true, filename_char_filter);
            return;
        }
    }

    if (me.left_pressed()) {
        if (lo.back_btn.contains(me.x, me.y)) { file_go_back(st); return; }
        if (lo.forward_btn.contains(me.x, me.y)) { file_go_forward(st); return; }
        if (lo.up_btn.contains(me.x, me.y)) { file_go_up(st); return; }
        if (lo.home_btn.contains(me.x, me.y)) { file_go_home(st); return; }
        if (lo.view_btn.contains(me.x, me.y)) {
            st->grid_view = !st->grid_view;
            st->scrollbar.scroll_offset = 0;
            return;
        }
        if (lo.cancel_btn.contains(me.x, me.y)) { dialog_cancel(); return; }
        if (lo.confirm_btn.contains(me.x, me.y)) {
            if (save_mode) file_accept_save(st);
            else file_accept_open(st);
            return;
        }
        if (lo.path_rect.contains(me.x, me.y)) {
            st->focus = FOCUS_PATH;
            if (save_mode) mtk::context_menu_close(st->filename_input.context);
            file_field_mouse(st->path_input, lo.path_rect, st->path_buf, (int)sizeof(st->path_buf),
                             me, true, nullptr);
            return;
        }
        if (save_mode && lo.name_rect.contains(me.x, me.y)) {
            st->focus = FOCUS_NAME;
            mtk::context_menu_close(st->path_input.context);
            file_field_mouse(st->filename_input, lo.name_rect, st->filename_buf,
                             (int)sizeof(st->filename_buf), me, true, filename_char_filter);
            return;
        }

        // Clicking elsewhere dismisses any open field menu and leaves the fields.
        mtk::context_menu_close(st->path_input.context);
        if (save_mode) mtk::context_menu_close(st->filename_input.context);

        int idx = file_entry_at(st, me.x, me.y);
        if (idx >= 0) {
            uint64_t now = montauk::get_milliseconds();
            st->focus = FOCUS_LIST;
            if (st->last_click_item == idx && (now - st->last_click_time) < 400) {
                st->selected = idx;
                file_activate_selected(st, true);
                st->last_click_item = -1;
                st->last_click_time = 0;
            } else {
                st->selected = idx;
                st->last_click_item = idx;
                st->last_click_time = now;
                if (save_mode && !st->is_dir[idx]) {
                    file_set_filename(st, st->entry_names[idx]);
                }
            }
            file_ensure_selected_visible(st);
            return;
        }

        st->selected = -1;
        st->focus = FOCUS_LIST;
    }

    if (me.scroll != 0 && lo.content_rect.contains(me.x, me.y)) {
        int step = st->grid_view ? GRID_CELL_H : ITEM_H;
        st->scrollbar.scroll_offset -= me.scroll * step;
        int ms = st->scrollbar.max_scroll();
        if (st->scrollbar.scroll_offset < 0) st->scrollbar.scroll_offset = 0;
        if (st->scrollbar.scroll_offset > ms) st->scrollbar.scroll_offset = ms;
    }
}

void handle_file_key(const montauk::abi::KeyEvent& key) {
    if (!key.pressed) return;

    FileDialogState* st = &g_file;

    bool save_mode = g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE;

    if (key.scancode == 0x01) {
        // Escape closes an open field menu first, otherwise cancels the dialog.
        if (st->path_input.context.open) { mtk::context_menu_close(st->path_input.context); return; }
        if (st->filename_input.context.open) { mtk::context_menu_close(st->filename_input.context); return; }
        dialog_cancel();
        return;
    }

    if (st->focus == FOCUS_PATH) {
        if (key.ascii == '\n' || key.ascii == '\r') {
            file_open_path(st, st->path_buf);
            st->focus = FOCUS_LIST;
            return;
        }
        mtk::text_input_key(st->path_input, st->path_buf, (int)sizeof(st->path_buf), key);
        return;
    }

    if (st->focus == FOCUS_NAME && save_mode) {
        if (key.ascii == '\n' || key.ascii == '\r') { file_accept_save(st); return; }
        mtk::text_input_key(st->filename_input, st->filename_buf, (int)sizeof(st->filename_buf),
                            key, filename_char_filter);
        return;
    }

    if (key.ascii == '\n' || key.ascii == '\r') {
        if (save_mode) file_accept_save(st);
        else file_accept_open(st);
        return;
    }

    if (montauk::nav_scancode(key) == 0x4B || montauk::nav_scancode(key) == 0x48) {
        if (st->selected > 0) st->selected--;
        else if (st->entry_count > 0) st->selected = 0;
        file_ensure_selected_visible(st);
        return;
    }

    if (montauk::nav_scancode(key) == 0x4D || montauk::nav_scancode(key) == 0x50) {
        if (st->selected < st->entry_count - 1) st->selected++;
        else if (st->entry_count > 0) st->selected = st->entry_count - 1;
        file_ensure_selected_visible(st);
        return;
    }

    if (key.ctrl && (key.ascii == 'l' || key.ascii == 'L')) {
        st->focus = FOCUS_PATH;
        return;
    }

    if (key.ctrl && g_app.request.mode == gui::dialogs::FILE_DIALOG_SAVE && (key.ascii == 'n' || key.ascii == 'N')) {
        st->focus = FOCUS_NAME;
        return;
    }
}

} // namespace

namespace filedialog {

void init(const gui::dialogs::Request& req) {
    init_file_dialog(req);
}

void draw() {
    draw_file_dialog();
}

void handle_mouse(const montauk::abi::WinEvent& ev) {
    handle_file_mouse(ev);
}

void handle_key(const montauk::abi::KeyEvent& key) {
    handle_file_key(key);
}

void cleanup() {
    free_file_icons(&g_file);
}

} // namespace filedialog