Made encryption a pro feature

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

@@ -23,11 +23,13 @@ import android.content.Intent;
 import android.net.Uri;
 import android.os.Bundle;
 import android.text.TextUtils;
+import android.view.MenuItem;
 
 import java.util.ArrayList;
 
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
+import androidx.lifecycle.Lifecycle;
 
 public class ActivityCompose extends ActivityBilling implements FragmentManager.OnBackStackChangedListener {
     static final int REQUEST_CONTACT_TO = 1;
@@ -125,4 +127,16 @@ public class ActivityCompose extends ActivityBilling implements FragmentManager.
         if (getSupportFragmentManager().getBackStackEntryCount() == 0)
             finish();
     }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        switch (item.getItemId()) {
+            case android.R.id.home:
+                if (getLifecycle().getCurrentState().isAtLeast(Lifecycle.State.RESUMED))
+                    getSupportFragmentManager().popBackStack();
+                return true;
+            default:
+                return false;
+        }
+    }
 }

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

@@ -898,12 +898,15 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
     }
 
     private void onDecrypt(Intent intent) {
-        Intent data = new Intent();
-        data.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
-        data.putExtra(OpenPgpApi.EXTRA_USER_IDS, new String[]{intent.getStringExtra("to")});
-        data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
-
-        decrypt(data, intent.getLongExtra("id", -1));
+        if (Helper.isPro(this)) {
+            Intent data = new Intent();
+            data.setAction(OpenPgpApi.ACTION_DECRYPT_VERIFY);
+            data.putExtra(OpenPgpApi.EXTRA_USER_IDS, new String[]{intent.getStringExtra("to")});
+            data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+            decrypt(data, intent.getLongExtra("id", -1));
+        } else
+            onShowPro(intent);
     }
 
     private void onShowPro(Intent intent) {

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

@@ -488,27 +488,33 @@ public class FragmentCompose extends FragmentEx {
     }
 
     private void onEncrypt() {
-        try {
-            String to = etTo.getText().toString();
-            InternetAddress ato[] = (TextUtils.isEmpty(to) ? new InternetAddress[0] : InternetAddress.parse(to));
-            if (ato.length == 0)
-                throw new IllegalArgumentException(getString(R.string.title_to_missing));
-
-            String[] tos = new String[ato.length];
-            for (int i = 0; i < ato.length; i++)
-                tos[i] = ato[i].getAddress();
-
-            Intent data = new Intent();
-            data.setAction(OpenPgpApi.ACTION_SIGN_AND_ENCRYPT);
-            data.putExtra(OpenPgpApi.EXTRA_USER_IDS, tos);
-            data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
-
-            encrypt(data);
-        } catch (Throwable ex) {
-            if (ex instanceof IllegalArgumentException)
-                Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
-            else
-                Helper.unexpectedError(getContext(), ex);
+        if (Helper.isPro(getContext()))
+            try {
+                String to = etTo.getText().toString();
+                InternetAddress ato[] = (TextUtils.isEmpty(to) ? new InternetAddress[0] : InternetAddress.parse(to));
+                if (ato.length == 0)
+                    throw new IllegalArgumentException(getString(R.string.title_to_missing));
+
+                String[] tos = new String[ato.length];
+                for (int i = 0; i < ato.length; i++)
+                    tos[i] = ato[i].getAddress();
+
+                Intent data = new Intent();
+                data.setAction(OpenPgpApi.ACTION_SIGN_AND_ENCRYPT);
+                data.putExtra(OpenPgpApi.EXTRA_USER_IDS, tos);
+                data.putExtra(OpenPgpApi.EXTRA_REQUEST_ASCII_ARMOR, true);
+
+                encrypt(data);
+            } catch (Throwable ex) {
+                if (ex instanceof IllegalArgumentException)
+                    Snackbar.make(view, ex.getMessage(), Snackbar.LENGTH_LONG).show();
+                else
+                    Helper.unexpectedError(getContext(), ex);
+            }
+        else {
+            FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();
+            fragmentTransaction.replace(R.id.content_frame, new FragmentPro()).addToBackStack("pro");
+            fragmentTransaction.commit();
         }
     }