Allow more system themes

app/src/main/java/eu/faircode/email/ActivityBase.java

@@ -140,12 +140,26 @@ abstract class ActivityBase extends AppCompatActivity implements SharedPreferenc
                 case "black":
                     setTheme(R.style.AppThemeBlack);
                     break;
+
                 case "system":
+                case "blue_orange_system":
                     if ((uiMode & Configuration.UI_MODE_NIGHT_YES) != 0)
                         setTheme(R.style.AppThemeBlueOrangeDark);
                     else
                         setTheme(R.style.AppThemeBlueOrangeLight);
                     break;
+                case "yellow_purple_system":
+                    if ((uiMode & Configuration.UI_MODE_NIGHT_YES) != 0)
+                        setTheme(R.style.AppThemeYellowPurpleDark);
+                    else
+                        setTheme(R.style.AppThemeYellowPurpleLight);
+                    break;
+                case "red_green_system":
+                    if ((uiMode & Configuration.UI_MODE_NIGHT_YES) != 0)
+                        setTheme(R.style.AppThemeRedGreenDark);
+                    else
+                        setTheme(R.style.AppThemeRedGreenLight);
+                    break;
                 case "grey_system":
                     if ((uiMode & Configuration.UI_MODE_NIGHT_YES) != 0)
                         setTheme(R.style.AppThemeGreySteelBlueDark);

app/src/main/java/eu/faircode/email/FragmentOptionsDisplay.java

@@ -673,8 +673,7 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
                     checkedId == R.id.rbThemeYellowPurple ||
                     checkedId == R.id.rbThemeRedGreen ||
                     checkedId == R.id.rbThemeGrey);
-            swSystem.setEnabled(checkedId == R.id.rbThemeBlueOrange ||
+            swSystem.setEnabled(swDark.isEnabled());
-                    checkedId == R.id.rbThemeGrey);
 
             boolean reverse = (swReverse.isEnabled() && swReverse.isChecked());
             boolean dark = (swDark.isEnabled() && swDark.isChecked());
@@ -735,18 +734,21 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
                 case "light":
                 case "dark":
                 case "system":
+                case "blue_orange_system":
                 case "blue_orange_light":
                 case "blue_orange_dark":
                 case "orange_blue_light":
                 case "orange_blue_dark":
                     rgTheme.check(R.id.rbThemeBlueOrange);
                     break;
+                case "yellow_purple_system":
                 case "yellow_purple_light":
                 case "yellow_purple_dark":
                 case "purple_yellow_light":
                 case "purple_yellow_dark":
                     rgTheme.check(R.id.rbThemeYellowPurple);
                     break;
+                case "red_green_system":
                 case "red_green_light":
                 case "red_green_dark":
                 case "green_red_light":
@@ -779,21 +781,27 @@ public class FragmentOptionsDisplay extends FragmentBase implements SharedPrefer
                             switch (rgTheme.getCheckedRadioButtonId()) {
                                 case R.id.rbThemeBlueOrange:
                                     if (system)
-                                        prefs.edit().putString("theme", "system").apply();
+                                        prefs.edit().putString("theme", "blue_orange_system").apply();
                                     else
                                         prefs.edit().putString("theme",
                                                 (reverse ? "orange_blue" : "blue_orange") +
                                                         (dark ? "_dark" : "_light")).apply();
                                     break;
                                 case R.id.rbThemeYellowPurple:
-                                    prefs.edit().putString("theme",
+                                    if (system)
-                                            (reverse ? "purple_yellow" : "yellow_purple") +
+                                        prefs.edit().putString("theme", "yellow_purple_system").apply();
-                                                    (dark ? "_dark" : "_light")).apply();
+                                    else
+                                        prefs.edit().putString("theme",
+                                                (reverse ? "purple_yellow" : "yellow_purple") +
+                                                        (dark ? "_dark" : "_light")).apply();
                                     break;
                                 case R.id.rbThemeRedGreen:
-                                    prefs.edit().putString("theme",
+                                    if (system)
-                                            (reverse ? "green_red" : "red_green") +
+                                        prefs.edit().putString("theme", "red_green_system").apply();
-                                                    (dark ? "_dark" : "_light")).apply();
+                                    else
+                                        prefs.edit().putString("theme",
+                                                (reverse ? "green_red" : "red_green") +
+                                                        (dark ? "_dark" : "_light")).apply();
                                     break;
                                 case R.id.rbThemeGrey:
                                     if (system)