2 files changed, 88 insertions, 0 deletions

diff --git a/bootloader/x1000/gui.c b/bootloader/x1000/gui.c
index da20a9b128..a672c30380 100644
--- a/bootloader/x1000/gui.c
+++ b/bootloader/x1000/gui.c
@@ -111,3 +111,67 @@ void gui_shutdown(void)
 
     backlight_hw_off();
 }
+
+void gui_list_init(struct bl_list* list, struct viewport* vp)
+{
+    list->vp = vp;
+    list->num_items = 0;
+    list->selected_item = 0;
+    list->top_item = 0;
+    list->item_height = SYSFONT_HEIGHT;
+    list->draw_item = NULL;
+}
+
+void gui_list_draw(struct bl_list* list)
+{
+    struct bl_listitem item = {
+        .list = list,
+        .x = 0, .y = 0,
+        .width = list->vp->width,
+        .height = list->item_height,
+    };
+
+    struct viewport* old_vp = lcd_set_viewport(list->vp);
+    lcd_clear_viewport();
+
+    int items_on_screen = list->vp->height / list->item_height;
+    for(int i = 0; i < items_on_screen; ++i) {
+        item.index = list->top_item + i;
+        if(item.index >= list->num_items)
+            break;
+
+        list->draw_item(&item);
+
+        item.y += item.height;
+    }
+
+    lcd_set_viewport(old_vp);
+}
+
+void gui_list_select(struct bl_list* list, int item_index)
+{
+    /* clamp the selection */
+    list->selected_item = item_index;
+
+    if(list->selected_item < 0)
+        list->selected_item = 0;
+    else if(list->selected_item >= list->num_items)
+        list->selected_item = list->num_items - 1;
+
+    /* handle scrolling the list view */
+    int items_on_screen = list->vp->height / list->item_height;
+    int bottom_item = list->top_item + items_on_screen;
+
+    if(list->selected_item < list->top_item) {
+        list->top_item = list->selected_item;
+    } else if(list->selected_item >= bottom_item) {
+        list->top_item = list->selected_item - items_on_screen + 1;
+        if(list->top_item < 0)
+            list->top_item = 0;
+    }
+}
+
+void gui_list_scroll(struct bl_list* list, int delta)
+{
+    gui_list_select(list, list->selected_item + delta);
+}
diff --git a/bootloader/x1000/x1000bootloader.h b/bootloader/x1000/x1000bootloader.h
index c5984c9a91..9090523c14 100644
--- a/bootloader/x1000/x1000bootloader.h
+++ b/bootloader/x1000/x1000bootloader.h
@@ -23,6 +23,7 @@
 #define __X1000BOOTLOADER_H__
 
 #include "config.h"
+#include "lcd.h"
 #include <stddef.h>
 #include <stdint.h>
 #include <stdbool.h>
@@ -70,6 +71,24 @@ struct uimage_header;
  * GUI stuff
  */
 
+struct bl_listitem {
+    struct bl_list* list;
+
+    int index;
+    int x, y, width, height;
+};
+
+struct bl_list {
+    struct viewport* vp;
+
+    int num_items;
+    int selected_item;
+    int top_item;
+    int item_height;
+
+    void(*draw_item)(const struct bl_listitem* item);
+};
+
 void clearscreen(void);
 void putversion(void);
 void putcenter_y(int y, const char* msg);
@@ -81,6 +100,11 @@ void init_lcd(void);
 
 void gui_shutdown(void);
 
+void gui_list_init(struct bl_list* list, struct viewport* vp);
+void gui_list_draw(struct bl_list* list);
+void gui_list_select(struct bl_list* list, int item_index);
+void gui_list_scroll(struct bl_list* list, int delta);
+
 /*
  * Installer
  */