Rtc context menu (#78)

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## Description
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Add basic RTC context menu.

## Motivation and Context
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issue here -->
Improves user experience.

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## Types of changes
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- [x] Improvement (non-breaking change that adds a new feature)
- [ ] Bug fix (fixes an issue)
- [ ] Breaking change (breaking change)
- [ ] Config and build (change in the configuration and build system,
has no impact on code or features)

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- [ ] My code follows the code style of this project.
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- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.

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Makefile

@@ -62,6 +62,7 @@ SRCS = \
 	menu/views/startup.c \
 	menu/views/system_info.c \
 	menu/views/settings_editor.c \
+	menu/views/rtc.c \
 	utils/fs.c
 
 FONTS = \

src/menu/menu.c

@@ -148,6 +148,7 @@ static struct views_s {
     { view_music_player_init, view_music_player_display }, // MENU_MODE_MUSIC_PLAYER
     { view_credits_init, view_credits_display }, // MENU_MODE_CREDITS
     { view_settings_init, view_settings_display }, // MENU_MODE_SETTINGS_EDITOR
+    { view_rtc_init, view_rtc_display }, // MENU_MODE_RTC
     { view_load_rom_init, view_load_rom_display }, // MENU_MODE_LOAD_ROM
     { view_load_disk_init, view_load_disk_display }, // MENU_MODE_LOAD_DISK
     { view_load_emulator_init, view_load_emulator_display }, // MENU_MODE_LOAD_EMULATOR

src/menu/menu_state.h

@@ -32,6 +32,7 @@ typedef enum {
     MENU_MODE_MUSIC_PLAYER,
     MENU_MODE_CREDITS,
     MENU_MODE_SETTINGS_EDITOR,
+    MENU_MODE_RTC,
     MENU_MODE_LOAD_ROM,
     MENU_MODE_LOAD_DISK,
     MENU_MODE_LOAD_EMULATOR,

src/menu/views/browser.c

@@ -240,11 +240,16 @@ static void show_credits (menu_t *menu) {
     menu->next_mode = MENU_MODE_CREDITS;
 }
 
+static void edit_rtc (menu_t *menu) {
+    menu->next_mode = MENU_MODE_RTC;
+}
+
 static component_context_menu_t settings_context_menu = {
     .list = {
         { .text = "Edit settings", .action = edit_settings },
         { .text = "Show system info", .action = show_system_info },
         { .text = "Show credits", .action = show_credits },
+        { .text = "Adjust RTC", .action = edit_rtc },
         COMPONENT_CONTEXT_MENU_LIST_END,
     }
 };

src/menu/views/rtc.c

@@ -0,0 +1,66 @@
+#include <time.h>
+#include "views.h"
+
+// FIXME: add implementation!
+// struct {
+//     uint16_t seconds;
+//     uint16_t minutes;
+//     uint16_t hours;
+//     uint16_t day;
+//     uint16_t month;
+//     uint16_t year;
+// } adjusted_datetime;
+
+// static void save_adjusted_datetime () {
+
+// }
+
+static void process (menu_t *menu) {
+    if (menu->actions.back) {
+        menu->next_mode = MENU_MODE_BROWSER;
+    }
+}
+
+static void draw (menu_t *menu, surface_t *d) {
+    rdpq_attach(d, NULL);
+
+    component_background_draw();
+
+    component_layout_draw();
+
+	component_main_text_draw(
+        ALIGN_CENTER, VALIGN_TOP,
+        "ADJUST REAL TIME CLOCK\n"
+        "\n"
+        "\n"
+        "To set the date and time, please use the PC terminal\n"
+        "application and set via USB.\n\n"
+        "Current date & time: %s\n",
+        menu->current_time >= 0 ? ctime(&menu->current_time) : "Unknown\n"
+    );
+
+    component_main_text_draw(
+        ALIGN_LEFT, VALIGN_TOP,
+        "\n"
+        "\n"
+    );
+
+
+    component_actions_bar_text_draw(
+        ALIGN_LEFT, VALIGN_TOP,
+        "\n" // "A: Save\n"
+        "B: Back"
+    );
+
+    rdpq_detach_show();
+}
+
+
+void view_rtc_init (menu_t *menu) {
+    // Nothing to initialize (yet)
+}
+
+void view_rtc_display (menu_t *menu, surface_t *display) {
+    process(menu);
+    draw(menu, display);
+}

src/menu/views/views.h

@@ -47,6 +47,9 @@ void view_load_disk_display (menu_t *menu, surface_t *display);
 void view_settings_init (menu_t *menu);
 void view_settings_display (menu_t *menu, surface_t *display);
 
+void view_rtc_init (menu_t *menu);
+void view_rtc_display (menu_t *menu, surface_t *display);
+
 void view_load_emulator_init (menu_t *menu);
 void view_load_emulator_display (menu_t *menu, surface_t *display);