seamus

diff --git a/include/seamus.h b/include/seamus.h
index 0e19c5c68b5c69f68b4780ca5d2f2c6c827c09f8..c2f8af6a9e78ab3055055526e4d4caaf1c08cd9a 100644
--- a/include/seamus.h
+++ b/include/seamus.h
@@ -48,6 +48,8 @@ 	KEY_GOTO_END,
 	KEY_HOME,
 	KEY_GOTO_START,
 	KEY_SWITCH_MODE,
+	KEY_HALF_PAGE_UP,
+	KEY_HALF_PAGE_DOWN,
 };
 
 struct seamus_frontend {




diff --git a/src/ui.c b/src/ui.c
index a19d1cf7448db3368d882ba13c59658f4ee2649d..6ef76637078a9580f62243419d5aa5974af9a2ea 100644
--- a/src/ui.c
+++ b/src/ui.c
@@ -12,6 +12,7 @@ static int toggle_playing_status(struct seamus_frontend *seamus);
 static int update_scroll_position(struct seamus_frontend *seamus, int direction);
 static int scroll_page(struct seamus_frontend *seamus, int direction);
 static int scroll_to_extremes(struct seamus_frontend *seamus, int home);
+static int scroll_half_page(struct seamus_frontend *seamus, int direction);
 static int switch_window(struct seamus_frontend *seamus);
 static int update_status(Tickit *t, TickitEventFlags flags, void *_info, void *data);
 static int update_main_window(Tickit *t, TickitEventFlags flags, void *_info, void *data);
@@ -97,6 +98,8 @@ 	if (strcmp(str, "G") == 0) return KEY_GOTO_END;
 	if (strcmp(str, "Home") == 0) return KEY_HOME;
 	if (strcmp(str, "g") == 0) return KEY_GOTO_START;
 	if (strcmp(str, "Tab") == 0) return KEY_SWITCH_MODE;
+	if (strcmp(str, "C-u") == 0) return KEY_HALF_PAGE_UP;
+	if (strcmp(str, "C-d") == 0) return KEY_HALF_PAGE_DOWN;
 	return KEY_NONE;
 }
 
@@ -152,6 +155,16 @@ 		log_info("Go to start");
 		scroll_to_extremes(seamus, 1);
 		break;
 
+	case KEY_HALF_PAGE_UP:
+		log_info("Half page up");
+		scroll_half_page(seamus, -1);
+		break;
+
+	case KEY_HALF_PAGE_DOWN:
+		log_info("Half page down");
+		scroll_half_page(seamus, +1);
+		break;
+
 	case KEY_SWITCH_MODE:
 		switch_window(seamus);
 		break;
@@ -265,6 +278,40 @@ 		seamus->highlight_index = seamus->status->length - 1;
 	}
 
 	tickit_window_expose(seamus->main_window, NULL);
+	return 0;
+}
+
+static int
+scroll_half_page(struct seamus_frontend *seamus, int direction)
+{
+	if (seamus->status->length <= 0) {
+		return 0;
+	}
+
+	int visible_rows = tickit_window_lines(seamus->main_window) - QUEUE_START_LINE;
+	if (visible_rows <= 0) visible_rows = 1;
+
+	int step = visible_rows / 2;
+	if (step < 1) step = 1;
+
+	if (direction == 1) {
+		seamus->scroll_offset += step;
+
+		if (seamus->scroll_offset > seamus->status->length - visible_rows) {
+			seamus->scroll_offset = seamus->status->length - visible_rows;
+		}
+
+		if (seamus->scroll_offset < 0) seamus->scroll_offset = 0;
+		seamus->highlight_index = seamus->scroll_offset;
+	} else if (direction == -1) {
+		seamus->scroll_offset -= step;
+
+		if (seamus->scroll_offset < 0) seamus->scroll_offset = 0;
+		seamus->highlight_index = seamus->scroll_offset;
+	}
+
+	tickit_window_expose(seamus->main_window, NULL);
+
 	return 0;
 }