Fix #3249: Add RSS feed parser to Brave Today

BraveShared/BraveStrings.swift

@@ -1772,6 +1772,24 @@ extension Strings {
             value: "Add",
             comment: "To add a list of 1 or more rss feeds"
         )
+        public static let rssFeedLimitExceededAlertTitle = NSLocalizedString(
+            "today.rssFeedLimitExceededAlertTitle",
+            bundle: .braveShared,
+            value: "Feed limit exceeded",
+            comment: ""
+        )
+        public static let rssFeedLimitExceededAlertMessage = NSLocalizedString(
+            "today.rssFeedLimitExceededAlertMessage",
+            bundle: .braveShared,
+            value: "The free ad-supported version of Brave Today includes 5 RSS feeds. You can customize your feed selections from the Sources list.",
+            comment: ""
+        )
+        public static let rssFeedLimitRemainingFooter = NSLocalizedString(
+            "today.rssFeedLimitRemainingFooter",
+            bundle: .braveShared,
+            value: "You currently have %d RSS feeds in your Sources list. The free ad-supported version of Brave Today includes 5 RSS feeds. Support for unlimited feeds and OPML import will be coming soon. You can customize your feed selections from the Sources list.",
+            comment: "%d will be a number (i.e. 4)"
+        )
         public static let insecureSourcesHeader = NSLocalizedString(
             "today.insecureSourcesHeader",
             bundle: .braveShared,

Client.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -1,6 +1,15 @@
 {
   "object": {
     "pins": [
+      {
+        "package": "FeedKit",
+        "repositoryURL": "https://github.com/nmdias/FeedKit.git",
+        "state": {
+          "branch": null,
+          "revision": "68493a33d862c33c9a9f67ec729b3b7df1b20ade",
+          "version": "9.1.2"
+        }
+      },
       {
         "package": "Fuzi",
         "repositoryURL": "https://github.com/cezheng/Fuzi",

Client/Frontend/Brave Today/Composer/FeedDataSource+RSS.swift

@@ -19,6 +19,10 @@ struct RSSFeedLocation: Hashable {
 }
 
 extension FeedDataSource {
+    /// The maximum number of RSS sources that can be added
+    static let maximumNumberOfRSSFeeds = 5
+    /// Whether or not OPML parsing is avaialable
+    static let isOPMLParsingAvailable = false
 
     // MARK: - RSS Sources
 
@@ -38,6 +42,9 @@ extension FeedDataSource {
         if !location.url.isWebPage(includeDataURIs: false) {
             return false
         }
+        if rssFeedLocations.count >= Self.maximumNumberOfRSSFeeds {
+            return false
+        }
         let feedUrl = location.url.absoluteString
         if RSSFeedSource.get(with: feedUrl) != nil {
             return false

Client/Frontend/Settings/Brave Today/BraveTodayAddSourceResultsViewController.swift

@@ -65,7 +65,22 @@ class BraveTodayAddSourceResultsViewController: UITableViewController {
         }
     }
 
+    private func showMaximumReachedAlert() {
+        let alert = UIAlertController(
+            title: Strings.BraveToday.rssFeedLimitExceededAlertTitle,
+            message: Strings.BraveToday.rssFeedLimitExceededAlertMessage,
+            preferredStyle: .alert
+        )
+        alert.addAction(.init(title: Strings.OKString, style: .default))
+        present(alert, animated: true)
+    }
+
     @objc private func tappedAdd() {
+        let numberOfAddedFeeds = feedDataSource.rssFeedLocations.count
+        if numberOfAddedFeeds + selectedLocations.count > FeedDataSource.maximumNumberOfRSSFeeds {
+            showMaximumReachedAlert()
+            return
+        }
         // Add selected sources to feed
         for location in selectedLocations {
             feedDataSource.addRSSFeedLocation(location)
@@ -124,6 +139,14 @@ class BraveTodayAddSourceResultsViewController: UITableViewController {
         }
         return nil
     }
+
+    override func tableView(_ tableView: UITableView, titleForFooterInSection section: Int) -> String? {
+        if section == tableView.numberOfSections - 1 {
+            let feedCount = feedDataSource.rssFeedLocations.count
+            return String.localizedStringWithFormat(Strings.BraveToday.rssFeedLimitRemainingFooter, feedCount)
+        }
+        return nil
+    }
 }
 
 private class FeedLocationCell: UITableViewCell, TableViewReusable {

Client/Frontend/Settings/Brave Today/BraveTodayAddSourceViewController.swift

@@ -189,11 +189,13 @@ class BraveTodayAddSourceViewController: UITableViewController {
                 return
             }
 
-            // Check if `data` is actually an OPML list
-            if let opml = OPMLParser.parse(data: data), !opml.outlines.isEmpty {
-                let locations = opml.outlines.compactMap(self.rssLocationFromOPMLOutline)
-                completion(locations.isEmpty ? .failure(.noFeedsFound) : .success(locations))
-                return
+            if FeedDataSource.isOPMLParsingAvailable {
+                // Check if `data` is actually an OPML list
+                if let opml = OPMLParser.parse(data: data), !opml.outlines.isEmpty {
+                    let locations = opml.outlines.compactMap(self.rssLocationFromOPMLOutline)
+                    completion(locations.isEmpty ? .failure(.noFeedsFound) : .success(locations))
+                    return
+                }
             }
 
             // Ensure page is reloaded to final landing page before looking for
@@ -301,7 +303,7 @@ class BraveTodayAddSourceViewController: UITableViewController {
     }
 
     override func numberOfSections(in tableView: UITableView) -> Int {
-        2
+        FeedDataSource.isOPMLParsingAvailable ? 2 : 1
     }
 
     override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {