fortrangoingonforty/sniffly / bc16410

+  'src/gui/cairo_tab_bar.f90',     # Cairo-rendered filing cabinet tabs

+! Cairo-rendered Filing Cabinet Tab Bar for Sniffly

+! Custom tab bar with squarrounded tabs that resemble filing cabinet tabs

+module cairo_tab_bar

+  use, intrinsic :: iso_c_binding

+  use gtk, only: gtk_drawing_area_new, gtk_drawing_area_set_draw_func, &

+                 gtk_widget_set_size_request, gtk_event_controller_motion_new, &

+                 gtk_widget_add_controller, gtk_gesture_click_new, &

+                 gtk_widget_queue_draw, gtk_widget_set_hexpand, g_signal_connect

+  use cairo, only: cairo_set_source_rgb, cairo_set_source_rgba, cairo_move_to, &

+                   cairo_line_to, cairo_curve_to, cairo_fill, cairo_stroke, &

+                   cairo_set_line_width, cairo_arc

+  use pango, only: pango_cairo_create_layout, pango_layout_set_text, &

+                   pango_font_description_from_string, pango_layout_set_font_description, &

+                   pango_cairo_show_layout, pango_layout_get_pixel_size, &

+                   pango_font_description_free

+  implicit none

+  private

+

+  public :: create_cairo_tab_bar, refresh_cairo_tab_bar, get_cairo_tab_bar_widget, &

+            register_cairo_tab_switch_callback, register_cairo_tab_close_callback, &

+            register_cairo_new_tab_callback

+

+  ! Tab dimensions

+  integer, parameter :: TAB_HEIGHT = 32

+  integer, parameter :: TAB_MIN_WIDTH = 120

+  integer, parameter :: TAB_MAX_WIDTH = 200

+  integer, parameter :: TAB_CORNER_RADIUS = 8

+  integer, parameter :: TAB_OVERLAP = 10

+  integer, parameter :: PLUS_BUTTON_WIDTH = 32

+  integer, parameter :: CLOSE_BUTTON_SIZE = 16

+  integer, parameter :: CLOSE_BUTTON_MARGIN = 8

+

+  ! Tab bar state

+  type(c_ptr), save :: tab_bar_widget = c_null_ptr

+  integer, save :: hovered_tab = 0  ! 0 = none, -1 = plus button, 1+ = tab index

+  integer, save :: hovered_close_button = 0  ! Which tab's close button is hovered

+

+  ! Tab bounds for hit testing

+  type :: tab_bounds

+    integer :: x, y, width, height

+    integer :: close_x, close_y  ! Close button position

+  end type tab_bounds

+

+  type(tab_bounds), dimension(5), save :: tab_rects  ! Max 5 tabs

+  integer :: plus_button_x, plus_button_y

+

+  ! Callback interfaces

+  abstract interface

+    subroutine tab_switch_callback(tab_index)

+      integer, intent(in) :: tab_index

+    end subroutine tab_switch_callback

+

+    subroutine tab_close_callback(tab_index)

+      integer, intent(in) :: tab_index

+    end subroutine tab_close_callback

+

+    subroutine new_tab_callback()

+    end subroutine new_tab_callback

+  end interface

+

+  ! Registered callbacks

+  procedure(tab_switch_callback), pointer, save :: switch_cb => null()

+  procedure(tab_close_callback), pointer, save :: close_cb => null()

+  procedure(new_tab_callback), pointer, save :: new_tab_cb => null()

+

+contains

+

+  ! Create the Cairo-rendered tab bar

+  function create_cairo_tab_bar() result(widget)

+    type(c_ptr) :: widget, motion_controller, click_controller

+

+    ! Create drawing area

+    widget = gtk_drawing_area_new()

+    tab_bar_widget = widget

+

+    if (.not. c_associated(widget)) then

+      print *, "ERROR: Failed to create cairo tab bar drawing area"

+      return

+    end if

+

+    ! Set fixed height, expand horizontally

+    call gtk_widget_set_size_request(widget, -1_c_int, TAB_HEIGHT)

+    call gtk_widget_set_hexpand(widget, 1_c_int)

+

+    ! Set draw function

+    call gtk_drawing_area_set_draw_func(widget, c_funloc(on_draw_tabs), &

+                                        c_null_ptr, c_null_ptr)

+

+    ! Add motion controller for hover effects

+    motion_controller = gtk_event_controller_motion_new()

+    call g_signal_connect(motion_controller, "motion"//c_null_char, &

+                          c_funloc(on_tab_motion), c_null_ptr)

+    call g_signal_connect(motion_controller, "leave"//c_null_char, &

+                          c_funloc(on_tab_leave), c_null_ptr)

+    call gtk_widget_add_controller(widget, motion_controller)

+

+    ! Add click controller

+    click_controller = gtk_gesture_click_new()

+    call g_signal_connect(click_controller, "pressed"//c_null_char, &

+                          c_funloc(on_tab_click), c_null_ptr)

+    call gtk_widget_add_controller(widget, click_controller)

+

+    print *, "Cairo tab bar created"

+  end function create_cairo_tab_bar

+

+  ! Draw the tab bar

+  subroutine on_draw_tabs(area, cr, width, height, user_data) bind(c)

+    use tab_manager, only: num_tabs, active_tab_index, get_tab, tab_state

+    type(c_ptr), value :: area, cr, user_data

+    integer(c_int), value :: width, height

+    type(tab_state), pointer :: tab

+    integer :: i, tab_x, tab_width, total_tabs_width

+    real(c_double) :: r, g, b, alpha

+

+    ! Clear background

+    call cairo_set_source_rgb(cr, 0.95_c_double, 0.95_c_double, 0.95_c_double)

+    call cairo_move_to(cr, 0.0_c_double, 0.0_c_double)

+    call cairo_line_to(cr, real(width, c_double), 0.0_c_double)

+    call cairo_line_to(cr, real(width, c_double), real(height, c_double))

+    call cairo_line_to(cr, 0.0_c_double, real(height, c_double))

+    call cairo_fill(cr)

+

+    ! Calculate starting position (flush to right edge, no overlap between tabs)

+    total_tabs_width = num_tabs * TAB_MIN_WIDTH + PLUS_BUTTON_WIDTH

+    tab_x = width - total_tabs_width

+

+    ! Draw plus button first (leftmost)

+    call draw_plus_button(cr, tab_x, 0)

+    plus_button_x = tab_x

+    plus_button_y = 0

+    tab_x = tab_x + PLUS_BUTTON_WIDTH

+

+    ! First pass: calculate positions and store in tab_rects

+    do i = 1, num_tabs

+      tab => get_tab(i)

+      if (.not. associated(tab)) cycle

+

+      tab_width = TAB_MIN_WIDTH

+

+      ! Store bounds for hit testing

+      tab_rects(i)%x = tab_x

+      tab_rects(i)%y = 0

+      tab_rects(i)%width = tab_width

+      tab_rects(i)%height = TAB_HEIGHT

+

+      ! No overlap - tabs sit flush next to each other

+      tab_x = tab_x + tab_width

+    end do

+

+    ! Second pass: draw inactive tabs first (so they appear behind)

+    do i = 1, num_tabs

+      if (i == active_tab_index) cycle  ! Skip active tab

+      tab => get_tab(i)

+      if (.not. associated(tab)) cycle

+

+      call draw_inactive_tab(cr, tab_rects(i)%x, TAB_MIN_WIDTH, trim(tab%label), i == hovered_tab)

+    end do

+

+    ! Third pass: draw active tab last (so it appears on top)

+    if (active_tab_index >= 1 .and. active_tab_index <= num_tabs) then

+      tab => get_tab(active_tab_index)

+      if (associated(tab)) then

+        call draw_active_tab(cr, tab_rects(active_tab_index)%x, TAB_MIN_WIDTH, &

+                           trim(tab%label), active_tab_index == hovered_tab)

+      end if

+    end if

+  end subroutine on_draw_tabs

+

+  ! Draw an active tab (full brightness, merges into canvas)

+  subroutine draw_active_tab(cr, x, width, label, is_hovered)

+    type(c_ptr), intent(in) :: cr

+    integer, intent(in) :: x, width

+    character(len=*), intent(in) :: label

+    logical, intent(in) :: is_hovered

+    real(c_double) :: x_d, y_d, w_d, h_d, radius

+

+    x_d = real(x, c_double)

+    y_d = 0.0_c_double

+    w_d = real(width, c_double)

+    h_d = real(TAB_HEIGHT, c_double)

+    radius = real(TAB_CORNER_RADIUS, c_double)

+

+    ! Draw squarrounded shape (rounded top, flat bottom)

+    call cairo_move_to(cr, x_d, h_d)  ! Bottom left

+    call cairo_line_to(cr, x_d, y_d + radius)  ! Left edge

+    call cairo_arc(cr, x_d + radius, y_d + radius, radius, 3.14159_c_double, -1.57080_c_double)  ! Top left corner

+    call cairo_line_to(cr, x_d + w_d - radius, y_d)  ! Top edge

+    call cairo_arc(cr, x_d + w_d - radius, y_d + radius, radius, -1.57080_c_double, 0.0_c_double)  ! Top right corner

+    call cairo_line_to(cr, x_d + w_d, h_d)  ! Right edge to bottom

+

+    ! Fill with white/light gray (active color)

+    if (is_hovered) then

+      call cairo_set_source_rgb(cr, 1.0_c_double, 1.0_c_double, 1.0_c_double)

+    else

+      call cairo_set_source_rgb(cr, 0.98_c_double, 0.98_c_double, 0.98_c_double)

+    end if

+    call cairo_fill(cr)

+

+    ! Draw border (but not bottom for "seeping" effect)

+    call draw_tab_border_no_bottom(cr, x_d, y_d, w_d, h_d, radius)

+

+    ! Draw label

+    call draw_tab_label(cr, x, 0, width, TAB_HEIGHT, label, .false.)

+

+    ! Draw close button

+    call draw_close_button(cr, x, width, .false.)

+  end subroutine draw_active_tab

+

+  ! Draw an inactive tab (dimmed, with bottom border)

+  subroutine draw_inactive_tab(cr, x, width, label, is_hovered)

+    type(c_ptr), intent(in) :: cr

+    integer, intent(in) :: x, width

+    character(len=*), intent(in) :: label

+    logical, intent(in) :: is_hovered

+    real(c_double) :: x_d, y_d, w_d, h_d, radius

+

+    x_d = real(x, c_double)

+    y_d = 2.0_c_double  ! Slightly lower than active

+    w_d = real(width, c_double)

+    h_d = real(TAB_HEIGHT - 2, c_double)

+    radius = real(TAB_CORNER_RADIUS, c_double)

+

+    ! Draw squarrounded shape

+    call cairo_move_to(cr, x_d, y_d + h_d)  ! Bottom left

+    call cairo_line_to(cr, x_d, y_d + radius)  ! Left edge

+    call cairo_arc(cr, x_d + radius, y_d + radius, radius, 3.14159_c_double, -1.57080_c_double)

+    call cairo_line_to(cr, x_d + w_d - radius, y_d)

+    call cairo_arc(cr, x_d + w_d - radius, y_d + radius, radius, -1.57080_c_double, 0.0_c_double)

+    call cairo_line_to(cr, x_d + w_d, y_d + h_d)

+

+    ! Fill with darker gray (inactive)

+    if (is_hovered) then

+      call cairo_set_source_rgb(cr, 0.88_c_double, 0.88_c_double, 0.88_c_double)

+    else

+      call cairo_set_source_rgb(cr, 0.82_c_double, 0.82_c_double, 0.82_c_double)

+    end if

+    call cairo_fill(cr)

+

+    ! Draw full border including bottom

+    call draw_tab_border_full(cr, x_d, y_d, w_d, h_d, radius)

+

+    ! Draw label (dimmed)

+    call draw_tab_label(cr, x, 2, width, TAB_HEIGHT - 2, label, .true.)

+

+    ! Draw close button

+    call draw_close_button(cr, x, width, .true.)

+  end subroutine draw_inactive_tab

+

+  ! Draw tab border without bottom (for active tab)

+  subroutine draw_tab_border_no_bottom(cr, x, y, width, height, radius)

+    type(c_ptr), intent(in) :: cr

+    real(c_double), intent(in) :: x, y, width, height, radius

+

+    call cairo_set_source_rgb(cr, 0.7_c_double, 0.7_c_double, 0.7_c_double)

+    call cairo_set_line_width(cr, 1.0_c_double)

+

+    call cairo_move_to(cr, x, y + height)

+    call cairo_line_to(cr, x, y + radius)

+    call cairo_arc(cr, x + radius, y + radius, radius, 3.14159_c_double, -1.57080_c_double)

+    call cairo_line_to(cr, x + width - radius, y)

+    call cairo_arc(cr, x + width - radius, y + radius, radius, -1.57080_c_double, 0.0_c_double)

+    call cairo_line_to(cr, x + width, y + height)

+    call cairo_stroke(cr)

+  end subroutine draw_tab_border_no_bottom

+

+  ! Draw full tab border (for inactive tabs)

+  subroutine draw_tab_border_full(cr, x, y, width, height, radius)

+    type(c_ptr), intent(in) :: cr

+    real(c_double), intent(in) :: x, y, width, height, radius

+

+    call cairo_set_source_rgb(cr, 0.6_c_double, 0.6_c_double, 0.6_c_double)

+    call cairo_set_line_width(cr, 1.0_c_double)

+

+    call cairo_move_to(cr, x, y + height)

+    call cairo_line_to(cr, x, y + radius)

+    call cairo_arc(cr, x + radius, y + radius, radius, 3.14159_c_double, -1.57080_c_double)

+    call cairo_line_to(cr, x + width - radius, y)

+    call cairo_arc(cr, x + width - radius, y + radius, radius, -1.57080_c_double, 0.0_c_double)

+    call cairo_line_to(cr, x + width, y + height)

+    call cairo_line_to(cr, x, y + height)

+    call cairo_stroke(cr)

+  end subroutine draw_tab_border_full

+

+  ! Draw tab label text

+  subroutine draw_tab_label(cr, x, y, width, height, text, is_dimmed)

+    type(c_ptr), intent(in) :: cr

+    integer, intent(in) :: x, y, width, height

+    character(len=*), intent(in) :: text

+    logical, intent(in) :: is_dimmed

+    type(c_ptr) :: layout, font_desc

+    integer(c_int), target :: text_width, text_height

+    real(c_double) :: text_x, text_y

+

+    ! Create pango layout

+    layout = pango_cairo_create_layout(cr)

+    call pango_layout_set_text(layout, trim(text)//c_null_char, -1_c_int)

+

+    ! Set font

+    font_desc = pango_font_description_from_string("Sans 10"//c_null_char)

+    call pango_layout_set_font_description(layout, font_desc)

+

+    ! Get text size

+    call pango_layout_get_pixel_size(layout, c_loc(text_width), c_loc(text_height))

+

+    ! Center text in tab (leaving room for close button)

+    text_x = real(x, c_double) + real(width - CLOSE_BUTTON_SIZE - CLOSE_BUTTON_MARGIN - text_width, c_double) / 2.0_c_double

+    text_y = real(y, c_double) + real(height - text_height, c_double) / 2.0_c_double

+

+    ! Set text color

+    if (is_dimmed) then

+      call cairo_set_source_rgb(cr, 0.4_c_double, 0.4_c_double, 0.4_c_double)

+    else

+      call cairo_set_source_rgb(cr, 0.2_c_double, 0.2_c_double, 0.2_c_double)

+    end if

+

+    call cairo_move_to(cr, text_x, text_y)

+    call pango_cairo_show_layout(cr, layout)

+

+    call pango_font_description_free(font_desc)

+  end subroutine draw_tab_label

+

+  ! Draw close button (×)

+  subroutine draw_close_button(cr, tab_x, tab_width, is_dimmed)

+    type(c_ptr), intent(in) :: cr

+    integer, intent(in) :: tab_x, tab_width

+    logical, intent(in) :: is_dimmed

+    real(c_double) :: btn_x, btn_y, btn_size

+

+    btn_x = real(tab_x + tab_width - CLOSE_BUTTON_SIZE - CLOSE_BUTTON_MARGIN, c_double)

+    btn_y = real((TAB_HEIGHT - CLOSE_BUTTON_SIZE) / 2, c_double)

+    btn_size = real(CLOSE_BUTTON_SIZE, c_double)

+

+    ! Draw × symbol

+    call cairo_set_line_width(cr, 1.5_c_double)

+    if (is_dimmed) then

+      call cairo_set_source_rgb(cr, 0.5_c_double, 0.5_c_double, 0.5_c_double)

+    else

+      call cairo_set_source_rgb(cr, 0.3_c_double, 0.3_c_double, 0.3_c_double)

+    end if

+

+    ! Draw X

+    call cairo_move_to(cr, btn_x + 4.0_c_double, btn_y + 4.0_c_double)

+    call cairo_line_to(cr, btn_x + btn_size - 4.0_c_double, btn_y + btn_size - 4.0_c_double)

+    call cairo_stroke(cr)

+

+    call cairo_move_to(cr, btn_x + btn_size - 4.0_c_double, btn_y + 4.0_c_double)

+    call cairo_line_to(cr, btn_x + 4.0_c_double, btn_y + btn_size - 4.0_c_double)

+    call cairo_stroke(cr)

+  end subroutine draw_close_button

+

+  ! Draw plus button

+  subroutine draw_plus_button(cr, x, y)

+    type(c_ptr), intent(in) :: cr

+    integer, intent(in) :: x, y

+    real(c_double) :: btn_x, btn_y, btn_size

+    logical :: is_hovered

+

+    is_hovered = (hovered_tab == -1)

+

+    btn_x = real(x, c_double) + 4.0_c_double

+    btn_y = real(y, c_double) + 4.0_c_double

+    btn_size = real(PLUS_BUTTON_WIDTH - 8, c_double)

+

+    ! Draw circle background

+    if (is_hovered) then

+      call cairo_set_source_rgb(cr, 0.9_c_double, 0.9_c_double, 0.9_c_double)

+    else

+      call cairo_set_source_rgb(cr, 0.85_c_double, 0.85_c_double, 0.85_c_double)

+    end if

+    call cairo_arc(cr, btn_x + btn_size / 2.0_c_double, btn_y + btn_size / 2.0_c_double, &

+                   btn_size / 2.0_c_double, 0.0_c_double, 6.28319_c_double)

+    call cairo_fill(cr)

+

+    ! Draw + symbol

+    call cairo_set_line_width(cr, 2.0_c_double)

+    call cairo_set_source_rgb(cr, 0.3_c_double, 0.3_c_double, 0.3_c_double)

+

+    ! Horizontal line

+    call cairo_move_to(cr, btn_x + 6.0_c_double, btn_y + btn_size / 2.0_c_double)

+    call cairo_line_to(cr, btn_x + btn_size - 6.0_c_double, btn_y + btn_size / 2.0_c_double)

+    call cairo_stroke(cr)

+

+    ! Vertical line

+    call cairo_move_to(cr, btn_x + btn_size / 2.0_c_double, btn_y + 6.0_c_double)

+    call cairo_line_to(cr, btn_x + btn_size / 2.0_c_double, btn_y + btn_size - 6.0_c_double)

+    call cairo_stroke(cr)

+  end subroutine draw_plus_button

+

+  ! Handle mouse motion for hover effects

+  subroutine on_tab_motion(controller, x, y, user_data) bind(c)

+    use tab_manager, only: num_tabs

+    type(c_ptr), value :: controller, user_data

+    real(c_double), value :: x, y

+    integer :: i, old_hovered

+

+    old_hovered = hovered_tab

+    hovered_tab = 0

+

+    ! Check plus button

+    if (x >= plus_button_x .and. x < plus_button_x + PLUS_BUTTON_WIDTH .and. &

+        y >= plus_button_y .and. y < plus_button_y + TAB_HEIGHT) then

+      hovered_tab = -1

+    else

+      ! Check tabs

+      do i = 1, num_tabs

+        if (x >= tab_rects(i)%x .and. x < tab_rects(i)%x + tab_rects(i)%width .and. &

+            y >= tab_rects(i)%y .and. y < tab_rects(i)%y + tab_rects(i)%height) then

+          hovered_tab = i

+          exit

+        end if

+      end do

+    end if

+

+    ! Redraw if hover state changed

+    if (hovered_tab /= old_hovered .and. c_associated(tab_bar_widget)) then

+      call gtk_widget_queue_draw(tab_bar_widget)

+    end if

+  end subroutine on_tab_motion

+

+  ! Handle mouse leave (clear hover state)

+  subroutine on_tab_leave(controller, user_data) bind(c)

+    type(c_ptr), value :: controller, user_data

+

+    ! Clear hover state when mouse leaves the tab bar

+    if (hovered_tab /= 0 .and. c_associated(tab_bar_widget)) then

+      hovered_tab = 0

+      hovered_close_button = 0

+      call gtk_widget_queue_draw(tab_bar_widget)

+    end if

+  end subroutine on_tab_leave

+

+  ! Handle clicks

+  subroutine on_tab_click(gesture, n_press, x, y, user_data) bind(c)

+    use tab_manager, only: num_tabs

+    type(c_ptr), value :: gesture, user_data

+    integer(c_int), value :: n_press

+    real(c_double), value :: x, y

+    integer :: i

+

+    ! Check plus button

+    if (x >= plus_button_x .and. x < plus_button_x + PLUS_BUTTON_WIDTH .and. &

+        y >= plus_button_y .and. y < plus_button_y + TAB_HEIGHT) then

+      if (associated(new_tab_cb)) call new_tab_cb()

+      return

+    end if

+

+    ! Check tabs

+    do i = 1, num_tabs

+      if (x >= tab_rects(i)%x .and. x < tab_rects(i)%x + tab_rects(i)%width .and. &

+          y >= tab_rects(i)%y .and. y < tab_rects(i)%y + tab_rects(i)%height) then

+

+        ! Check if close button was clicked

+        if (x >= tab_rects(i)%x + tab_rects(i)%width - CLOSE_BUTTON_SIZE - CLOSE_BUTTON_MARGIN .and. &

+            x < tab_rects(i)%x + tab_rects(i)%width - CLOSE_BUTTON_MARGIN) then

+          if (associated(close_cb)) call close_cb(i)

+        else

+          ! Tab body clicked

+          if (associated(switch_cb)) call switch_cb(i)

+        end if

+        return

+      end if

+    end do

+  end subroutine on_tab_click

+

+  ! Refresh (trigger redraw)

+  subroutine refresh_cairo_tab_bar()

+    if (c_associated(tab_bar_widget)) then

+      call gtk_widget_queue_draw(tab_bar_widget)

+    end if

+  end subroutine refresh_cairo_tab_bar

+

+  ! Get widget

+  function get_cairo_tab_bar_widget() result(widget)

+    type(c_ptr) :: widget

+    widget = tab_bar_widget

+  end function get_cairo_tab_bar_widget

+

+  ! Register callbacks

+  subroutine register_cairo_tab_switch_callback(callback)

+    procedure(tab_switch_callback) :: callback

+    switch_cb => callback

+  end subroutine register_cairo_tab_switch_callback

+

+  subroutine register_cairo_tab_close_callback(callback)

+    procedure(tab_close_callback) :: callback

+    close_cb => callback

+  end subroutine register_cairo_tab_close_callback

+

+  subroutine register_cairo_new_tab_callback(callback)

+    procedure(new_tab_callback) :: callback

+    new_tab_cb => callback

+  end subroutine register_cairo_new_tab_callback

+

+end module cairo_tab_bar

+                         switch_to_tab, close_tab, num_tabs, active_tab_index, get_path_basename

+  use cairo_tab_bar, only: create_cairo_tab_bar, refresh_cairo_tab_bar, &

+                           register_cairo_tab_switch_callback, register_cairo_tab_close_callback, &

+                           register_cairo_new_tab_callback

+    ! Create Cairo-rendered tab bar (on right side of breadcrumb row)

+    tab_bar = create_cairo_tab_bar()

+      ! Register callbacks for tab interactions

+      call register_cairo_tab_switch_callback(on_cairo_tab_switch)

+      call register_cairo_tab_close_callback(on_cairo_tab_close)

+      call register_cairo_new_tab_callback(on_cairo_new_tab)

+      ! Trigger initial draw

+      call refresh_cairo_tab_bar()

+      print *, "Cairo tab bar added to breadcrumb row"

+      print *, "ERROR: Failed to create Cairo tab bar"

+    ! Add CSS class for card styling (border that matches active tab)

+    call gtk_widget_add_css_class(drawing_area, "canvas-card"//c_null_char)

+

+    ! and card border styling to match active tab appearance

+      "} " // &

+      ".canvas-card { " // &

+      "background-color: rgba(250, 250, 250, 1.0); " // &

+      "border: 1px solid rgba(179, 179, 179, 1.0); " // &

+      "border-top: none; " // &

+    print *, "Custom CSS loaded (pulsing animation + canvas card styling)"

+  ! Cairo tab bar callback wrappers

+  subroutine on_cairo_tab_switch(tab_index)

+    integer, intent(in) :: tab_index

+

+    ! Skip if already on this tab

+    if (tab_index == active_tab_index) return

+

+    print *, "Cairo tab switch to tab ", tab_index

+

+    ! Switch to the clicked tab

+    call switch_to_tab(tab_index)

+

+    ! Trigger redraw of tab bar (highlights active tab)

+    call refresh_cairo_tab_bar()

+

+    ! Update UI for the new active tab

+    call update_ui_for_active_tab()

+

+    print *, "Switched to tab ", tab_index

+  end subroutine on_cairo_tab_switch

+

+  subroutine on_cairo_tab_close(tab_index)

+    integer, intent(in) :: tab_index

+

+    print *, "Cairo tab close for tab ", tab_index

+

+    ! Prevent closing last tab

+    if (num_tabs <= 1) then

+      print *, "ERROR: Cannot close last tab"

+      return

+    end if

+

+    ! Close the tab

+    call close_tab(tab_index)

+

+    ! Trigger redraw of tab bar

+    call refresh_cairo_tab_bar()

+

+    ! Update UI for the new active tab

+    call update_ui_for_active_tab()

+

+    print *, "Tab ", tab_index, " closed - now ", num_tabs, " tabs remaining"

+  end subroutine on_cairo_tab_close

+

+  subroutine on_cairo_new_tab()

+    integer :: new_tab_index

+    character(len=512) :: new_tab_path

+

+    print *, "Cairo new tab button clicked"

+

+    ! New tabs start completely empty - no path to avoid accidental scans

+    new_tab_path = ""

+

+    ! Create a new empty tab

+    new_tab_index = create_tab(new_tab_path)

+

+    if (new_tab_index < 0) then

+      print *, "ERROR: Failed to create new tab (max tabs reached?)"

+      return

+    end if

+

+    print *, "Created new tab ", new_tab_index

+

+    ! Switch to the new tab

+    call switch_to_tab(new_tab_index)

+

+    ! Trigger redraw of tab bar

+    call refresh_cairo_tab_bar()

+

+    ! Update UI for the new tab

+    call update_ui_for_active_tab()

+

+    print *, "Tab bar refreshed and switched to new tab ", new_tab_index

+  end subroutine on_cairo_new_tab

+

+    ! Refresh Cairo tab bar to show updated label

+    call refresh_cairo_tab_bar()