Allow optionally dragging URLs with the mouse

Fixes #9804

docs/changelog.rst

@@ -183,6 +183,8 @@ Detailed list of changes
 
 - :doc:`Remote control <remote-control>`: Expose :code:`session_name` and :code:`last_focused_at` in the output of ``kitten @ ls`` for each window (:iss:`9732`, :iss:`9799`)
 
+- Allow optionally dragging URLs with the mouse, see :sc:`start_simple_selection` (:pull:`9804`)
+
 - Fix thickness of diagonal lines in box drawing characters not the same as horizontal/vertical lines (:iss:`9719`)
 
 - Graphics protocol: Fix crash when handling invalid PNG image with direct transmission

kitty/fast_data_types.pyi

@@ -1260,6 +1260,7 @@ class Screen:
     def hyperlink_for_id(self, hyperlink_id: int) -> str: ...
     def erase_last_command(self, include_prompt: bool = True) -> bool: ...
     def set_progress(self, state: int, percent: int) -> None: ...
+    def mark_potential_url_drag(self) -> bool: ...
 
     def cursor_at_prompt(self) -> bool:
         pass

kitty/mouse.c

@@ -413,9 +413,10 @@ handle_mouse_movement_in_kitty(Window *w, int button, bool mouse_cell_changed) {
 static void
 detect_url(Screen *screen, unsigned int x, unsigned int y) {
     int hid = screen_detect_url(screen, x, y);
-    screen->current_hyperlink_under_mouse.id = 0;
+    zero_at_ptr(&screen->current_hyperlink_under_mouse);
     if (hid != 0) {
         mouse_cursor_shape = POINTER_POINTER;
+        screen->current_hyperlink_under_mouse.has_detected_url = hid < 0;
         if (hid > 0) {
             screen->current_hyperlink_under_mouse.id = (hyperlink_id_type)hid;
             screen->current_hyperlink_under_mouse.x = x;
@@ -672,16 +673,26 @@ HANDLER(handle_move_event) {
     if (should_handle_in_kitty(w, screen, button)) {
         handle_mouse_movement_in_kitty(w, button, mouse_cell_changed | cell_half_changed);
     } else {
-        if (!mouse_cell_changed && screen->modes.mouse_tracking_protocol != SGR_PIXEL_PROTOCOL) return;
-        int sz = encode_mouse_button(w, button, button >=0 ? DRAG : MOVE, modifiers);
-        if (sz > 0) { mouse_event_buf[sz] = 0; write_escape_code_to_child(screen, ESC_CSI, mouse_event_buf); }
+        if (mouse_cell_changed || screen->modes.mouse_tracking_protocol == SGR_PIXEL_PROTOCOL) {
+            int sz = encode_mouse_button(w, button, button >=0 ? DRAG : MOVE, modifiers);
+            if (sz > 0) { mouse_event_buf[sz] = 0; write_escape_code_to_child(screen, ESC_CSI, mouse_event_buf); }
+        }
     }
-    if (w->drag_source.can_offer && w->drag_source.initial_left_press.at && distance(w->mouse_pos.global_x, w->mouse_pos.global_y, w->drag_source.initial_left_press.x, w->drag_source.initial_left_press.y) > OPT(drag_threshold)) {
+    if (w->drag_source.initial_left_press.at && distance(w->mouse_pos.global_x, w->mouse_pos.global_y, w->drag_source.initial_left_press.x, w->drag_source.initial_left_press.y) > OPT(drag_threshold)) {
         zero_at_ptr(&w->drag_source.initial_left_press);
-        snprintf(mouse_event_buf, sizeof(mouse_event_buf), "%d;t=o:x=%d:y=%d:X=%d:Y=%d",
-            DND_CODE, w->mouse_pos.cell_x, w->mouse_pos.cell_y, (int)w->mouse_pos.global_x, (int)w->mouse_pos.global_y);
-        write_escape_code_to_child(screen, ESC_OSC, mouse_event_buf);
-        debug("Sent drag start event to child\n");
+        if (w->drag_source.can_offer) {
+            snprintf(mouse_event_buf, sizeof(mouse_event_buf), "%d;t=o:x=%d:y=%d:X=%d:Y=%d",
+                DND_CODE, w->mouse_pos.cell_x, w->mouse_pos.cell_y, (int)w->mouse_pos.global_x, (int)w->mouse_pos.global_y);
+            write_escape_code_to_child(screen, ESC_OSC, mouse_event_buf);
+            debug("Sent drag start event to child\n");
+        } else if (w->drag_source.potential_url_drag.active) {
+            w->drag_source.potential_url_drag.active = false;
+            screen_detect_url(screen, w->drag_source.potential_url_drag.x, w->drag_source.potential_url_drag.y);
+            if (screen->current_hyperlink_under_mouse.id || screen->current_hyperlink_under_mouse.has_detected_url) {
+                screen_open_url(screen, "drag_url");
+                debug("Started URL drag\n");
+            }
+        }
     }
 }
 
@@ -749,7 +760,7 @@ bool
 mouse_open_url(Window *w) {
     Screen *screen = w->render_data.screen;
     detect_url(screen, w->mouse_pos.cell_x, w->mouse_pos.cell_y);
-    return screen_open_url(screen);
+    return screen_open_url(screen, "open_url");
 }
 
 bool
@@ -847,6 +858,7 @@ HANDLER(handle_button_event) {
     modifiers &= ~GLFW_LOCK_MASK;
     OSWindow *osw = global_state.callback_os_window;
     if (!osw) return;
+    w->drag_source.potential_url_drag.active = false;
 
     Tab *t = osw->tabs + osw->active_tab;
     bool is_release = !osw->mouse_button_pressed[button];
@@ -879,7 +891,7 @@ HANDLER(handle_button_event) {
     if (button == GLFW_MOUSE_BUTTON_LEFT) {
         if (is_release) {
             zero_at_ptr(&w->drag_source.initial_left_press);
-        } else if (w->drag_source.can_offer) {
+        } else {
             w->drag_source.initial_left_press.x = w->mouse_pos.global_x;
             w->drag_source.initial_left_press.y = w->mouse_pos.global_x;
             w->drag_source.initial_left_press.at = monotonic();

kitty/options/definition.py

@@ -988,6 +988,12 @@
 
 mma('Start selecting text',
     'start_simple_selection left press ungrabbed mouse_selection normal',
+    long_text='''
+If you would like to drag and drop hyperlinks or detected URLs, instead of
+:code:`normal` use :code:`drag_or_normal_select`, then if a hyperlink is under
+the mouse it will be dragged based on :opt:`drag_threshold` otherwise a normal
+selection will be performed.
+'''
     )
 
 mma('Start selecting text in a rectangle',

kitty/options/utils.py

@@ -446,6 +446,7 @@ def mouse_selection(func: str, rest: str) -> FuncArgsType:
             'normal': defines.MOUSE_SELECTION_NORMAL,
             'extend': defines.MOUSE_SELECTION_EXTEND,
             'move-end': defines.MOUSE_SELECTION_MOVE_END,
+            'move_end': defines.MOUSE_SELECTION_MOVE_END,
             'rectangle': defines.MOUSE_SELECTION_RECTANGLE,
             'word': defines.MOUSE_SELECTION_WORD,
             'line': defines.MOUSE_SELECTION_LINE,
@@ -453,6 +454,7 @@ def mouse_selection(func: str, rest: str) -> FuncArgsType:
             'line_from_point': defines.MOUSE_SELECTION_LINE_FROM_POINT,
             'word_and_line_from_point': defines.MOUSE_SELECTION_WORD_AND_LINE_FROM_POINT,
             'upto_surrounding_whitespace': defines.MOUSE_SELECTION_UPTO_SURROUNDING_WHITESPACE,
+            'drag_or_normal_select': defines.MOUSE_SELECTION_NORMAL - 1,
         }
         setattr(mouse_selection, 'code_map', cmap)
     return func, [cmap[rest]]

kitty/screen.c

@@ -1512,6 +1512,16 @@ screen_dirty_line_graphics(Screen *self, const unsigned int top, const unsigned
         grman_remove_cell_images(main_buf ? self->main_grman : self->alt_grman, top, bottom);
 }
 
+static bool
+screen_mark_potential_url_drag(Screen *self) {
+    Window *w;
+    if ((!self->current_hyperlink_under_mouse.id && !self->current_hyperlink_under_mouse.has_detected_url) || !self->window_id || !(w = window_for_window_id(self->window_id))) return false;
+    w->drag_source.potential_url_drag.active = true;
+    w->drag_source.potential_url_drag.x = w->mouse_pos.cell_x;
+    w->drag_source.potential_url_drag.y = w->mouse_pos.cell_y;
+    return true;
+}
+
 void
 screen_handle_dnd_command(Screen *self, const DnDCommand *cmd, const uint8_t *payload) {
     if (!self->window_id) return;
@@ -4084,13 +4094,13 @@ current_url_text(Screen *self, PyObject *args UNUSED) {
 
 
 bool
-screen_open_url(Screen *self) {
+screen_open_url(Screen *self, const char *callback) {
     if (!self->url_ranges.count) return false;
     hyperlink_id_type hid = hyperlink_id_for_range(self, self->url_ranges.items);
     if (hid) {
         const char *url = get_hyperlink_for_id(self->hyperlink_pool, hid, true);
         if (url) {
-            CALLBACK("open_url", "sH", url, hid);
+            CALLBACK(callback, "sH", url, hid);
             return true;
         }
     }
@@ -4101,7 +4111,7 @@ screen_open_url(Screen *self) {
     }
     bool found = false;
     if (PyUnicode_Check(text)) {
-        CALLBACK("open_url", "OH", text, 0);
+        CALLBACK(callback, "OH", text, 0);
         found = true;
     }
     Py_CLEAR(text);
@@ -5948,6 +5958,12 @@ current_selections(Screen *self, PyObject *a UNUSED) {
 WRAP0(update_only_line_graphics_data)
 WRAP0(bell)
 
+static PyObject*
+mark_potential_url_drag(Screen *self, PyObject *a UNUSED) {
+    if (screen_mark_potential_url_drag(self)) Py_RETURN_TRUE;
+    Py_RETURN_FALSE;
+}
+
 #define MND(name, args) {#name, (PyCFunction)name, args, #name},
 #define MODEFUNC(name) MND(name, METH_NOARGS) MND(set_##name, METH_O)
 
@@ -6136,6 +6152,7 @@ static PyMethodDef methods[] = {
     MND(scroll_to_next_mark, METH_VARARGS)
     MND(update_only_line_graphics_data, METH_NOARGS)
     MND(bell, METH_NOARGS)
+    MND(mark_potential_url_drag, METH_NOARGS)
     MND(current_selections, METH_NOARGS)
     {"select_graphic_rendition", (PyCFunction)_select_graphic_rendition, METH_VARARGS, ""},
 

kitty/screen.h

@@ -186,6 +186,7 @@ typedef struct {
     struct {
         hyperlink_id_type id;
         index_type x, y;
+        bool has_detected_url;
     } current_hyperlink_under_mouse;
     struct {
         uint8_t stack[16], count;
@@ -305,7 +306,7 @@ hyperlink_id_type screen_mark_hyperlink(Screen*, index_type, index_type);
 void screen_handle_graphics_command(Screen *self, const GraphicsCommand *cmd, const uint8_t *payload);
 void screen_handle_multicell_command(Screen *self, const MultiCellCommand *cmd, const uint8_t *payload);
 void screen_handle_dnd_command(Screen *self, const DnDCommand *cmd, const uint8_t *payload);
-bool screen_open_url(Screen*);
+bool screen_open_url(Screen* self, const char* callback);
 bool screen_set_last_visited_prompt(Screen*, index_type);
 bool screen_select_cmd_output(Screen*, index_type);
 void screen_dirty_sprite_positions(Screen *self);

kitty/state.h

@@ -290,6 +290,7 @@ typedef struct Window {
     } drop;
     struct {
         bool can_offer;
+        struct { index_type x, y; bool active; } potential_url_drag;
         struct { double x, y; monotonic_t at; } initial_left_press;
         char *mimes_buf; size_t num_mimes, bufsz;
         struct {

kitty/window.py

@@ -48,6 +48,7 @@
     GLFW_PRESS,
     GLFW_RELEASE,
     GLFW_REPEAT,
+    MOUSE_SELECTION_NORMAL,
     NO_CURSOR_SHAPE,
     NULL_COLOR_VALUE,
     SCROLL_FULL,
@@ -65,6 +66,7 @@
     click_mouse_cmd_output,
     click_mouse_url,
     current_focused_os_window_id,
+    draw_single_line_of_text,
     encode_key_for_tty,
     get_boss,
     get_click_interval,
@@ -88,6 +90,7 @@
     set_window_padding,
     set_window_render_data,
     set_window_title_bar_render_data,
+    start_drag_with_data,
     update_ime_position_for_window,
     update_pointer_shape,
     update_window_title,
@@ -1309,6 +1312,24 @@ def on_mouse_event(self, event: dict[str, Any]) -> bool:
             return False
         return get_boss().combine(action, window_for_dispatch=self, dispatch_type='MouseEvent')
 
+    def drag_url(self, url: str, hyperlink_id: int) -> None:
+        if not url:
+            return
+        if url.startswith('/'):
+            from urllib.parse import quote
+            url = 'file://' + quote(os.path.abspath(url))
+        fg = color_as_int(self.screen.color_profile.default_fg)
+        bg = color_as_int(self.screen.color_profile.default_bg)
+        width = self.geometry.right - self.geometry.left
+        pixels = draw_single_line_of_text(self.os_window_id, url, 0xff000000 | fg, 0xff000000 | bg, width)
+        height = len(pixels) // (width * 4)
+        thumbnails = ((pixels, width, height),)
+        drag_data = {'text/uri-list': (url + '\r\n').encode()}
+        try:
+            start_drag_with_data(self.os_window_id, drag_data, thumbnails)
+        except OSError as e:
+            log_error(f'Failed to start URL drag: {e}')
+
     def open_url(self, url: str, hyperlink_id: int, cwd: str | None = None) -> None:
         boss = get_boss()
         try:
@@ -1841,6 +1862,10 @@ def mouse_click_url_or_select(self) -> None:
         For examples, see :ref:`conf-kitty-mouse.mousemap`
         ''')
     def mouse_selection(self, code: int) -> None:
+        if code == MOUSE_SELECTION_NORMAL - 1:
+            code = MOUSE_SELECTION_NORMAL
+            if self.screen.mark_potential_url_drag():
+                return
         mouse_selection(self.os_window_id, self.tab_id, self.id, code, self.current_mouse_event_button)
 
     @ac('mouse', 'Paste the current primary selection')