bug fix, added comments

app/src/main/java/org/nuclearfog/twidda/adapter/CardAdapter.java

@@ -27,7 +27,7 @@ public class CardAdapter extends RecyclerView.Adapter<CardHolder> implements OnI
 	private Picasso picasso;
 	private OnCardClickListener listener;
 
-	private Card[] cards;
+	private Card[] cards = {};
 
 
 	public CardAdapter(Context context, OnCardClickListener listener) {
@@ -71,7 +71,7 @@ public class CardAdapter extends RecyclerView.Adapter<CardHolder> implements OnI
 	 * replace all items
 	 * @param newCards new items to insert
 	 */
-	public void replaceAll(Card[] newCards) {
+	public void replaceAll(@NonNull Card[] newCards) {
 		cards = Arrays.copyOf(newCards, newCards.length);
 		notifyDataSetChanged();
 	}
@@ -81,8 +81,14 @@ public class CardAdapter extends RecyclerView.Adapter<CardHolder> implements OnI
 	 */
 	public interface OnCardClickListener {
 
+		/**
+		 * indicates a link click
+		 */
 		int TYPE_LINK = 1;
 
+		/**
+		 * indicates an image thumbnail click
+		 */
 		int TYPE_IMAGE = 2;
 
 		/**

app/src/main/java/org/nuclearfog/twidda/adapter/holder/CardHolder.java

@@ -31,9 +31,15 @@ public class CardHolder extends ViewHolder implements OnClickListener {
 	 */
 	private static final int TEXT_TRANSPARENCY = 0xafffffff;
 
+	/**
+	 * how much views should be fit in the window
+	 */
 	private static final int COLUMN_COUNT = 2;
 
-	private static final int MAX_TITLE_LEN = 20;
+	/**
+	 * maximum char count of the title before truncating
+	 */
+	private static final int TITLE_MAX_LEN = 30;
 
 	private TextView linkText;
 	private ImageView preview;
@@ -80,17 +86,17 @@ public class CardHolder extends ViewHolder implements OnClickListener {
 	public void setContent(Card card) {
 		String textStr;
 		String title = card.getTitle();
-		if (title.length() > MAX_TITLE_LEN)
+		if (title.length() > TITLE_MAX_LEN) {
-			textStr = title.substring(0, MAX_TITLE_LEN - 3) + "...";
+			textStr = title.substring(0, TITLE_MAX_LEN - 3) + "...";
-		else
+		} else {
 			textStr = title;
+		}
 		if (!card.getDescription().isEmpty())
 			textStr += '\n' + card.getDescription();
 		SpannableString textSpan = new SpannableString(textStr);
 		if (!title.isEmpty())
-			textSpan.setSpan(new StyleSpan(Typeface.BOLD), 0, title.length() - 1, 0);
+			textSpan.setSpan(new StyleSpan(Typeface.BOLD), 0, Math.min(textStr.length() - 1, TITLE_MAX_LEN), 0);
 		linkText.setText(textSpan);
-		//description.setText(card.getDescription());
 		if (!card.getImageUrl().isEmpty()) {
 			picasso.load(card.getImageUrl()).into(preview);
 		}
@@ -108,8 +114,14 @@ public class CardHolder extends ViewHolder implements OnClickListener {
 	 */
 	public interface OnItemClickListener {
 
+		/**
+		 * indicates a link click
+		 */
 		int TYPE_LINK = 1;
 
+		/**
+		 * indicates a click on the image
+		 */
 		int TYPE_IMAGE = 2;
 
 		/**

app/src/main/java/org/nuclearfog/twidda/backend/api/twitter/impl/TwitterCard.java

@@ -1,5 +1,7 @@
 package org.nuclearfog.twidda.backend.api.twitter.impl;
 
+import android.util.Patterns;
+
 import org.json.JSONArray;
 import org.json.JSONObject;
 import org.nuclearfog.twidda.model.Card;
@@ -16,7 +18,7 @@ public class TwitterCard implements Card {
 	private String url;
 	private String title;
 	private String description;
-	private String imageUrl;
+	private String imageUrl = "";
 
 
 	public TwitterCard(JSONObject json) {
@@ -25,14 +27,14 @@ public class TwitterCard implements Card {
 		title = json.optString("title", "");
 		description = json.optString("description", "");
 		if (images != null && images.length() > 0) {
+			// first index contains image with the highest resolutuion
 			JSONObject image = images.optJSONObject(0);
 			if (image != null) {
-				imageUrl = image.optString("url");
+				String imageUrl = image.optString("url", "");
-			} else {
+				if (Patterns.WEB_URL.matcher(imageUrl).matches()) {
-				imageUrl = "";
+					this.imageUrl = imageUrl;
+				}
 			}
-		} else {
-			imageUrl = "";
 		}
 	}
 

app/src/main/java/org/nuclearfog/twidda/backend/api/twitter/impl/TwitterNotification.java

@@ -33,6 +33,7 @@ public class TwitterNotification implements Notification {
 
 	@Override
 	public int getType() {
+		// Twitte rcurrently only supports mentions as notification
 		return TYPE_MENTION;
 	}
 

app/src/main/java/org/nuclearfog/twidda/backend/api/twitter/impl/UserV1.java

@@ -1,5 +1,7 @@
 package org.nuclearfog.twidda.backend.api.twitter.impl;
 
+import android.util.Patterns;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -54,11 +56,11 @@ public class UserV1 implements User {
 	public UserV1(JSONObject json) throws JSONException {
 		String idStr = json.getString("id_str");
 		String profileImageUrl = json.optString("profile_image_url_https", "");
+		String profileBannerUrl = json.optString("profile_banner_url", "");
 		username = json.optString("name", "");
 		screenName = '@' + json.optString("screen_name", "");
 		isVerified = json.optBoolean("verified");
 		isLocked = json.optBoolean("protected");
-		profileBannerUrl = json.optString("profile_banner_url", "");
 		location = json.optString("location", "");
 		following = json.optInt("friends_count");
 		follower = json.optInt("followers_count");
@@ -70,6 +72,17 @@ public class UserV1 implements User {
 		description = getDescription(json);
 		url = getUrl(json);
 
+		//
+		if (Patterns.WEB_URL.matcher(profileImageUrl).matches()) {
+			this.profileImageUrl = profileImageUrl;
+		} else {
+			this.profileImageUrl = "";
+		}
+		if (Patterns.WEB_URL.matcher(profileBannerUrl).matches()) {
+			this.profileBannerUrl = profileBannerUrl;
+		} else {
+			this.profileBannerUrl = "";
+		}
 		if (defaultImage) {
 			this.profileImageUrl = profileImageUrl;
 		} else {

app/src/main/java/org/nuclearfog/twidda/backend/api/twitter/impl/UserV2.java

@@ -1,5 +1,7 @@
 package org.nuclearfog.twidda.backend.api.twitter.impl;
 
+import android.util.Patterns;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
@@ -50,12 +52,12 @@ public class UserV2 implements User {
 
 		String idStr = json.getString("id");
 		String profileImageUrl = json.optString("profile_image_url", "");
+		String profileBannerUrl = json.optString("profile_banner_url", "");
 		username = json.optString("name", "");
 		screenName = '@' + json.optString("username", "");
 		isProtected = json.optBoolean("protected");
 		location = json.optString("location", "");
 		isVerified = json.optBoolean("verified");
-		profileBannerUrl = json.optString("profile_banner_url", "");
 		created = StringTools.getTime(json.optString("created_at", ""), StringTools.TIME_TWITTER_V2);
 		defaultImage = profileImageUrl.contains("default_profile_images");
 
@@ -67,10 +69,19 @@ public class UserV2 implements User {
 			follower = metrics.optInt("followers_count");
 			tweetCount = metrics.optInt("tweet_count");
 		}
-		if (defaultImage) {
+		if  (Patterns.WEB_URL.matcher(profileImageUrl).matches()) {
-			this.profileImageUrl = profileImageUrl;
+			if (defaultImage) {
+				this.profileImageUrl = profileImageUrl;
+			} else {
+				this.profileImageUrl = StringTools.createProfileImageLink(profileImageUrl);
+			}
 		} else {
-			this.profileImageUrl = StringTools.createProfileImageLink(profileImageUrl);
+			this.profileImageUrl = "";
+		}
+		if (Patterns.WEB_URL.matcher(profileBannerUrl).matches()) {
+			this.profileBannerUrl = profileBannerUrl;
+		} else {
+			this.profileBannerUrl = "";
 		}
 		try {
 			id = Long.parseLong(idStr);