Second commit

Signed-off-by: Mattias Andrée <m@maandree.se>

1 files changed, 135 insertions, 0 deletions

diff --git a/dragging.c b/dragging.c
new file mode 100644
index 0000000..3ac3ff5
--- /dev/null
+++ b/dragging.c
@@ -0,0 +1,135 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+static char url_list_name[] = "text/uri-list";
+static GtkTargetEntry url_list = {url_list_name, 0u, 0u};
+
+static int dragging = 0;
+static int drag_source_disabled = 0;
+static int drag_x, drag_y;
+
+static void
+set_file_drag_source(GtkWidget *widget)
+{
+	gtk_drag_source_set(widget, GDK_BUTTON1_MASK, &url_list, 1u,
+	                    GDK_ACTION_COPY | GDK_ACTION_MOVE | GDK_ACTION_LINK | GDK_ACTION_ASK);
+}
+
+static int
+button_pressed(GtkWidget *widget, GdkEventButton *event, void *user)
+{
+	(void) user;
+	if (event->button == 2u || (event->state & GDK_CONTROL_MASK)) {
+		if (event->button == 1u) {
+			gtk_drag_source_unset(widget);
+			drag_source_disabled = 1;
+		}
+		dragging = 1;
+		drag_x = (int)event->x_root;
+		drag_y = (int)event->y_root;
+	}
+	return dragging;
+}
+
+static int
+button_released(GtkWidget *widget, GdkEventButton *event, void *user)
+{
+	(void) event;
+	(void) user;
+	dragging = 0;
+	if (drag_source_disabled) {
+		set_file_drag_source(widget);
+		drag_source_disabled = 0;
+	}
+	return 0;
+}
+
+static int
+pointer_moved(GtkWidget *widget, GdkEventMotion *event, void *user)
+{
+	int x, y;
+	(void) event;
+	(void) user;
+	if (dragging) {
+		gdk_display_get_pointer(gtk_widget_get_display(widget), NULL, &x, &y, NULL);
+		scroll_by(drag_x - x, drag_y - y);
+		drag_x = x;
+		drag_y = y;
+	}
+	return dragging;
+}
+
+static void
+drag_begin(GtkWidget *widget, GdkDragContext *context, void *user)
+{
+	GdkPixbuf *image, *icon;
+	intmax_t height, width;
+
+	(void) widget;
+	(void) user;
+
+	image = get_original_image();
+	if (!image)
+		return;
+
+	width = gdk_pixbuf_get_width(image);
+	height = gdk_pixbuf_get_height(image);
+	if (width <= DRAG_ICON_SIZE && height <= DRAG_ICON_SIZE) {
+		gtk_drag_set_icon_pixbuf(context, image, 0, 0);
+		return;
+	}
+	if (width >= height) {
+		height = height * DRAG_ICON_SIZE / width;
+		height = MAX(1, height);
+		width = DRAG_ICON_SIZE;
+	} else {
+		width = width * DRAG_ICON_SIZE / height;
+		width = MAX(1, width);
+		height = DRAG_ICON_SIZE;
+	}
+	icon = gdk_pixbuf_scale_simple(image, (int)width, (int)height, GDK_INTERP_BILINEAR);
+	if (!icon)
+		return;
+	gtk_drag_set_icon_pixbuf(context, icon, 0, 0);
+	g_object_unref(icon);
+}
+
+static void
+drag_data_get(GtkWidget *widget, GdkDragContext *context, GtkSelectionData *data,
+              unsigned int info, unsigned int time, void *user)
+{
+	struct file *file = get_file();
+	GError *error = NULL;
+	char *uri;
+
+	(void) widget;
+	(void) context;
+	(void) info;
+	(void) time;
+	(void) user;
+
+	if (!file || !file->path)
+		return;
+
+	uri = g_filename_to_uri(file->path, NULL, &error);
+	if (!uri) {
+		weprintf("g_filename_to_uri: %s", error->message);
+		g_error_free(error);
+		return;
+	}
+	gtk_selection_data_set_uris(data, (char *[]){uri, NULL});
+	g_free(uri);
+}
+
+void
+set_up_dragging(void)
+{
+	set_file_drag_source(display_area);
+
+	g_signal_connect(display_area, "button-press-event", G_CALLBACK(&button_pressed), NULL);
+	g_signal_connect(display_area, "button-release-event", G_CALLBACK(&button_released), NULL);
+	g_signal_connect(display_area, "motion-notify-event", G_CALLBACK(&pointer_moved), NULL);
+
+	g_signal_connect(display_area, "drag-begin", G_CALLBACK(&drag_begin), NULL);
+	g_signal_connect(display_area, "drag-data-get", G_CALLBACK(&drag_data_get), NULL);
+}