Add --scrollbar option

5 files changed, 76 insertions, 16 deletions

diff --git a/lib/bemenu.h b/lib/bemenu.h
index 54d82f9..490132f 100644
--- a/lib/bemenu.h
+++ b/lib/bemenu.h
@@ -387,6 +387,22 @@ bool bm_menu_set_color(struct bm_menu *menu, enum bm_color color, const char *he
 const char* bm_menu_get_color(const struct bm_menu *menu, enum bm_color color);
 
 /**
+ * Display scrollbar at left side of the menu.
+ *
+ * @param menu bm_menu instance to set scrollbar for.
+ * @param scrollbar true for scrollbar, false for no scrollbar.
+ */
+void bm_menu_set_scrollbar(struct bm_menu *menu, bool scrollbar);
+
+/**
+ * Is scrollbar being displayed on the menu?
+ *
+ * @param menu bm_menu instance where to get scrollbar display state from.
+ * @return true if scrollbar displayed, false otherwise.
+ */
+bool bm_menu_get_scrollbar(struct bm_menu *menu);
+
+/**
  * Display menu at bottom of the screen.
  * This may be no-op on some renderers (curses, wayland)
  *
diff --git a/lib/internal.h b/lib/internal.h
index 7b71eb4..5291b56 100644
--- a/lib/internal.h
+++ b/lib/internal.h
@@ -287,6 +287,11 @@ struct bm_menu {
      * Is menu grabbed?
      */
     bool grabbed;
+
+    /**
+     * Scrollbar enabled?
+     */
+    bool scrollbar;
 };
 
 /* library.c */
diff --git a/lib/menu.c b/lib/menu.c
index 4fc00e7..0b39d83 100644
--- a/lib/menu.c
+++ b/lib/menu.c
@@ -296,6 +296,18 @@ char* bm_menu_get_color(const struct bm_menu *menu, enum bm_color color)
 }
 
 void
+bm_menu_set_scrollbar(struct bm_menu *menu, bool scrollbar)
+{
+    menu->scrollbar = scrollbar;
+}
+
+bool
+bm_menu_get_scrollbar(struct bm_menu *menu)
+{
+    return menu->scrollbar;
+}
+
+void
 bm_menu_set_bottom(struct bm_menu *menu, bool bottom)
 {
     assert(menu);
diff --git a/lib/renderers/cairo.h b/lib/renderers/cairo.h
index 5eb5b68..c135a51 100644
--- a/lib/renderers/cairo.h
+++ b/lib/renderers/cairo.h
@@ -197,29 +197,31 @@ bm_cairo_paint(struct cairo *cairo, uint32_t width, uint32_t height, uint32_t ma
     paint.pos = (struct pos){ (menu->title ? 2 : 0) + result.x_advance, 2 };
     paint.box = (struct box){ (menu->title ? 2 : 4), 0, 2, 2, width - paint.pos.x, 0 };
     bm_cairo_draw_line(cairo, &paint, &result, "%s", (menu->filter ? menu->filter : ""));
-    out_result->height = result.height;
 
     uint32_t count;
     struct bm_item **items = bm_menu_get_filtered_items(menu, &count);
     uint32_t lines = (menu->lines > 0 ? menu->lines : 1);
+    uint32_t titleh = result.height;
+    out_result->height = titleh;
 
     if (lines > 1) {
         /* vertical mode */
 
-        uint32_t spacing = 0; // 0 == variable width spacing
-        if (lines > max_height / result.height) {
+        uint32_t spacing_x = (menu->scrollbar ? 4 : 0);
+        uint32_t spacing_y = 0; // 0 == variable width spacing
+        if (lines > max_height / titleh) {
             /* there is more lines than screen can fit, enter fixed spacing mode */
-            lines = max_height / result.height - 1;
-            spacing = result.height;
+            lines = max_height / titleh - 1;
+            spacing_y = titleh;
         }
 
-        uint32_t start_x = 0;
+        uint32_t prefix_x = 0;
         if (menu->prefix) {
             bm_pango_get_text_extents(cairo, &paint, &result, "%s ", menu->prefix);
-            start_x = result.x_advance;
+            prefix_x += result.x_advance;
         }
 
-        uint32_t posy = out_result->height;
+        uint32_t posy = titleh;
         for (uint32_t l = 0, i = (menu->index / lines) * lines; l < lines && i < count && posy < max_height; ++i, ++l) {
             bool highlighted = (items[i] == bm_menu_get_highlighted_item(menu));
 
@@ -236,18 +238,33 @@ bm_cairo_paint(struct cairo *cairo, uint32_t width, uint32_t height, uint32_t ma
 
             if (menu->prefix && highlighted) {
                 paint.pos = (struct pos){ 0, 2 + posy };
-                paint.box = (struct box){ 4, 0, 2, 2, width - paint.pos.x, 0 };
+                paint.box = (struct box){ 4 + spacing_x, 0, 2, 2, width - paint.pos.x, 0 };
                 bm_cairo_draw_line(cairo, &paint, &result, "%s %s", menu->prefix, (items[i]->text ? items[i]->text : ""));
             } else {
                 paint.pos = (struct pos){ 0, 2 + posy };
-                paint.box = (struct box){ 4 + start_x, 0, 2, 2, width - paint.pos.x, 0 };
+                paint.box = (struct box){ 4 + spacing_x + prefix_x, 0, 2, 2, width - paint.pos.x, 0 };
                 bm_cairo_draw_line(cairo, &paint, &result, "%s", (items[i]->text ? items[i]->text : ""));
             }
 
-            posy += (spacing ? spacing : result.height);
+            posy += (spacing_y ? spacing_y : result.height);
             out_result->height = posy + 2;
             out_result->displayed++;
         }
+
+        if (menu->scrollbar && count > 0) {
+            uint32_t sheight = out_result->height - titleh;
+            bm_cairo_color_from_menu_color(menu, BM_COLOR_TITLE_FG, &paint.bg);
+            cairo_set_source_rgba(cairo->cr, paint.bg.r, paint.bg.b, paint.bg.g, paint.bg.a);
+            cairo_rectangle(cairo->cr, 0, titleh, 2, sheight);
+            cairo_fill(cairo->cr);
+
+            uint32_t size = sheight / lines;
+            uint32_t percent = (menu->index / (float)(count - 1)) * (sheight - size);
+            bm_cairo_color_from_menu_color(menu, BM_COLOR_BG, &paint.bg);
+            cairo_set_source_rgba(cairo->cr, paint.bg.r, paint.bg.b, paint.bg.g, paint.bg.a);
+            cairo_rectangle(cairo->cr, 0, titleh + percent, 2, size);
+            cairo_fill(cairo->cr);
+        }
     } else {
         /* single-line mode */
         bm_pango_get_text_extents(cairo, &paint, &result, "lorem ipsum lorem ipsum lorem ipsum lorem");
diff --git a/lib/renderers/curses/curses.c b/lib/renderers/curses/curses.c
index af54846..bab031b 100644
--- a/lib/renderers/curses/curses.c
+++ b/lib/renderers/curses/curses.c
@@ -186,20 +186,30 @@ render(const struct bm_menu *menu)
 
     uint32_t count, cl = 1;
     const uint32_t lines = getmaxy(curses.stdscr);
+    const int32_t prefix_x = (menu->prefix ? bm_utf8_string_screen_width(menu->prefix) : 0);
+    const int32_t offset_x = (menu->scrollbar ? 2 : 0);
     if (lines > 1) {
+        uint32_t displayed = 0;
         struct bm_item **items = bm_menu_get_filtered_items(menu, &count);
         for (uint32_t i = (menu->index / (lines - 1)) * (lines - 1); i < count && cl < lines; ++i) {
             bool highlighted = (items[i] == bm_menu_get_highlighted_item(menu));
             int32_t color = (highlighted ? 2 : (bm_menu_item_is_selected(menu, items[i]) ? 1 : 0));
 
             if (menu->prefix && highlighted) {
-                draw_line(color, cl++, "%s %s", menu->prefix, (items[i]->text ? items[i]->text : ""));
-            } else if (menu->prefix) {
-                int32_t offset = (menu->prefix ? bm_utf8_string_screen_width(menu->prefix) : 0);
-                draw_line(color, cl++, "%*s %s", offset, "", (items[i]->text ? items[i]->text : ""));
+                draw_line(color, cl++, "%*s%s %s", offset_x, "", menu->prefix, (items[i]->text ? items[i]->text : ""));
             } else {
-                draw_line(color, cl++, "%s", (items[i]->text ? items[i]->text : ""));
+                draw_line(color, cl++, "%*s%s%s", offset_x + prefix_x, "", (menu->prefix ? " " : ""), (items[i]->text ? items[i]->text : ""));
             }
+
+            ++displayed;
+        }
+
+        if (menu->scrollbar) {
+            attron(COLOR_PAIR(1));
+            uint32_t percent = (menu->index / (float)(count - 1)) * (displayed - 1);
+            for (uint32_t i = 0; i < displayed; ++i)
+                mvprintw(1 + i, 0, (i == percent ? "█" : "▒"));
+            attroff(COLOR_PAIR(1));
         }
     }