feat(Boost For Reddit): Add Fix /s/ links patch (#631)

Co-authored-by: oSumAtrIX <[email protected]>

app/src/main/java/app/revanced/integrations/boostforreddit/FixSLinksPatch.java

@@ -0,0 +1,24 @@
+package app.revanced.integrations.boostforreddit;
+
+import com.rubenmayayo.reddit.ui.activities.WebViewActivity;
+
+import app.revanced.integrations.shared.fixes.slink.BaseFixSLinksPatch;
+
+/** @noinspection unused*/
+public class FixSLinksPatch extends BaseFixSLinksPatch {
+    static {
+        INSTANCE = new FixSLinksPatch();
+    }
+
+    private FixSLinksPatch() {
+        webViewActivityClass = WebViewActivity.class;
+    }
+
+    public static boolean patchResolveSLink(String link) {
+        return INSTANCE.resolveSLink(link);
+    }
+
+    public static void patchSetAccessToken(String accessToken) {
+        INSTANCE.setAccessToken(accessToken);
+    }
+}

app/src/main/java/app/revanced/integrations/shared/fixes/slink/BaseFixSLinksPatch.java

@@ -0,0 +1,208 @@
+package app.revanced.integrations.shared.fixes.slink;
+
+
+import android.app.Activity;
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import androidx.annotation.NonNull;
+import app.revanced.integrations.shared.Logger;
+import app.revanced.integrations.shared.Utils;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.SocketTimeoutException;
+import java.net.URL;
+import java.util.Objects;
+
+import static app.revanced.integrations.shared.Utils.getContext;
+
+
+/**
+ * Base class to implement /s/ link resolution in 3rd party Reddit apps.
+ * <br>
+ * <br>
+ * Usage:
+ * <br>
+ * <br>
+ * An implementation of this class must have two static methods that are called by the app:
+ * <ul>
+ *     <li>public static boolean patchResolveSLink(String link)</li>
+ *     <li>public static void patchSetAccessToken(String accessToken)</li>
+ * </ul>
+ * The static methods must call the instance methods of the base class.
+ * <br>
+ * The singleton pattern can be used to access the instance of the class:
+ * <pre>
+ * {@code
+ * {
+ *     INSTANCE = new FixSLinksPatch();
+ * }
+ * }
+ * </pre>
+ * Set the app's web view activity class as a fallback to open /s/ links if the resolution fails:
+ * <pre>
+ * {@code
+ * private FixSLinksPatch() {
+ *     webViewActivityClass = WebViewActivity.class;
+ * }
+ * }
+ * </pre>
+ * Hook the app's navigation handler to call this method before doing any of its own resolution:
+ * <pre>
+ * {@code
+ * public static boolean patchResolveSLink(Context context, String link) {
+ *     return INSTANCE.resolveSLink(context, link);
+ * }
+ * }
+ * </pre>
+ * If this method returns true, the app should early return and not do any of its own resolution.
+ * <br>
+ * <br>
+ * Hook the app's access token so that this class can use it to resolve /s/ links:
+ * <pre>
+ * {@code
+ * public static void patchSetAccessToken(String accessToken) {
+ *     INSTANCE.setAccessToken(access_token);
+ * }
+ * }
+ * </pre>
+ */
+public abstract class BaseFixSLinksPatch {
+    /**
+     * The class of the activity used to open links in a web view if resolving them fails.
+     */
+    protected Class<? extends Activity> webViewActivityClass;
+
+    /**
+     * The access token used to resolve the /s/ link.
+     */
+    protected String accessToken;
+
+    /**
+     * The URL that was trying to be resolved before the access token was set.
+     * If this is not null, the URL will be resolved right after the access token is set.
+     */
+    protected String pendingUrl;
+
+    /**
+     * The singleton instance of the class.
+     */
+    protected static BaseFixSLinksPatch INSTANCE;
+
+    public boolean resolveSLink(String link) {
+        switch (resolveLink(link)) {
+            case ACCESS_TOKEN_START: {
+                pendingUrl = link;
+                return true;
+            }
+            case DO_NOTHING:
+                return true;
+            default:
+                return false;
+        }
+    }
+
+    private ResolveResult resolveLink(String link) {
+        Context context = getContext();
+        if (link.matches(".*reddit\\.com/r/[^/]+/s/[^/]+")) {
+            // A link ends with #bypass if it failed to resolve below.
+            // resolveLink is called with the same link again but this time with #bypass
+            // so that the link is opened in the app browser instead of trying to resolve it again.
+            if (link.endsWith("#bypass")) {
+                openInAppBrowser(context, link);
+
+                return ResolveResult.DO_NOTHING;
+            }
+
+            Logger.printDebug(() -> "Resolving " + link);
+
+            if (accessToken == null) {
+                // This is not optimal.
+                // However, an accessToken is necessary to make an authenticated request to Reddit.
+                // in case Reddit has banned the IP - e.g. VPN.
+                Intent startIntent = context.getPackageManager().getLaunchIntentForPackage(context.getPackageName());
+                context.startActivity(startIntent);
+
+                return ResolveResult.ACCESS_TOKEN_START;
+            }
+
+
+            Utils.runOnBackgroundThread(() -> {
+                String bypassLink = link + "#bypass";
+
+                String finalLocation = bypassLink;
+                try {
+                    HttpURLConnection connection = getHttpURLConnection(link, accessToken);
+                    connection.connect();
+                    String location = connection.getHeaderField("location");
+                    connection.disconnect();
+
+                    Objects.requireNonNull(location, "Location is null");
+
+                    finalLocation = location;
+                    Logger.printDebug(() -> "Resolved " + link + " to " + location);
+                } catch (SocketTimeoutException e) {
+                    Logger.printException(() -> "Timeout when trying to resolve " + link, e);
+                    finalLocation = bypassLink;
+                } catch (Exception e) {
+                    Logger.printException(() -> "Failed to resolve " + link, e);
+                    finalLocation = bypassLink;
+                } finally {
+                    Intent startIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(finalLocation));
+                    startIntent.setPackage(context.getPackageName());
+                    startIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                    context.startActivity(startIntent);
+                }
+            });
+
+            return ResolveResult.DO_NOTHING;
+        }
+
+        return ResolveResult.CONTINUE;
+    }
+
+    public void setAccessToken(String accessToken) {
+        Logger.printDebug(() -> "Setting access token");
+
+        this.accessToken = accessToken;
+
+        // In case a link was trying to be resolved before access token was set.
+        // The link is resolved now, after the access token is set.
+        if (pendingUrl != null) {
+            String link = pendingUrl;
+            pendingUrl = null;
+
+            Logger.printDebug(() -> "Opening pending URL");
+
+            resolveLink(link);
+        }
+    }
+
+    private void openInAppBrowser(Context context, String link) {
+        Intent intent = new Intent(context, webViewActivityClass);
+        intent.putExtra("url", link);
+        context.startActivity(intent);
+    }
+
+    @NonNull
+    private HttpURLConnection getHttpURLConnection(String link, String accessToken) throws IOException {
+        URL url = new URL(link);
+
+        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+        connection.setInstanceFollowRedirects(false);
+        connection.setRequestMethod("HEAD");
+        connection.setConnectTimeout(2000);
+        connection.setReadTimeout(2000);
+
+        if (accessToken != null) {
+            Logger.printDebug(() -> "Setting access token to make /s/ request");
+
+            connection.setRequestProperty("Authorization", "Bearer " + accessToken);
+        } else {
+            Logger.printDebug(() -> "Not setting access token to make /s/ request, because it is null");
+        }
+
+        return connection;
+    }
+}

app/src/main/java/app/revanced/integrations/shared/fixes/slink/ResolveResult.java

@@ -0,0 +1,10 @@
+package app.revanced.integrations.shared.fixes.slink;
+
+public enum ResolveResult {
+    // Let app handle rest of stuff
+    CONTINUE,
+    // Start app, to make it cache its access_token
+    ACCESS_TOKEN_START,
+    // Don't do anything - we started resolving
+    DO_NOTHING
+}

app/src/main/java/app/revanced/integrations/syncforreddit/FixSLinksPatch.java

@@ -1,42 +1,24 @@
 package app.revanced.integrations.syncforreddit;
 
-import android.os.StrictMode;
-import app.revanced.integrations.shared.Logger;
+import com.laurencedawson.reddit_sync.ui.activities.WebViewActivity;
 
-import java.net.HttpURLConnection;
-import java.net.URL;
+import app.revanced.integrations.shared.fixes.slink.BaseFixSLinksPatch;
 
-public final class FixSLinksPatch {
-    public static String resolveSLink(String link) {
-        if (link.matches(".*reddit\\.com/r/[^/]+/s/[^/]+")) {
-            Logger.printInfo(() -> "Resolving " + link);
-            try {
-                URL url = new URL(link);
-                HttpURLConnection connection = (HttpURLConnection) url.openConnection();
-                connection.setInstanceFollowRedirects(false);
-                connection.setRequestMethod("HEAD");
-
-                // Disable strict mode in order to allow network access on the main thread.
-                // This is not ideal, but it's the easiest solution for now.
-                final var currentPolicy = StrictMode.getThreadPolicy();
-                StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
-                StrictMode.setThreadPolicy(policy);
-
-                connection.connect();
-                String location = connection.getHeaderField("location");
-                connection.disconnect();
-
-                // Restore the original strict mode policy.
-                StrictMode.setThreadPolicy(currentPolicy);
+/** @noinspection unused*/
+public class FixSLinksPatch extends BaseFixSLinksPatch {
+    static {
+        INSTANCE = new FixSLinksPatch();
+    }
 
-                Logger.printInfo(() -> "Resolved " + link + " -> " + location);
+    private FixSLinksPatch() {
+        webViewActivityClass = WebViewActivity.class;
+    }
 
-                return location;
-            } catch (Exception e) {
-                Logger.printException(() -> "Failed to resolve " + link, e);
-            }
-        }
+    public static boolean patchResolveSLink(String link) {
+        return INSTANCE.resolveSLink(link);
+    }
 
-        return link;
+    public static void patchSetAccessToken(String accessToken) {
+        INSTANCE.setAccessToken(accessToken);
     }
 }

stub/src/main/java/com/laurencedawson/reddit_sync/ui/activities/WebViewActivity.java

@@ -0,0 +1,6 @@
+package com.laurencedawson.reddit_sync.ui.activities;
+
+import android.app.Activity;
+
+public class WebViewActivity extends Activity {
+}

stub/src/main/java/com/rubenmayayo/reddit/ui/activities/WebViewActivity.java

@@ -0,0 +1,6 @@
+package com.rubenmayayo.reddit.ui.activities;
+
+import android.app.Activity;
+
+public class WebViewActivity extends Activity {
+}