feat: mix and radio (#26)

Author: sozercan

Core/Models/ArtistDetail.swift

@@ -21,6 +21,10 @@ struct ArtistDetail: Sendable {
     let songsBrowseId: String?
     /// Params for loading all songs.
     let songsParams: String?
+    /// Playlist ID for Mix (personalized radio), e.g., "RDEM...".
+    let mixPlaylistId: String?
+    /// Starting video ID for Mix.
+    let mixVideoId: String?
 
     var id: String { self.artist.id }
     var name: String { self.artist.name }
@@ -36,7 +40,9 @@ struct ArtistDetail: Sendable {
         subscriberCount: String? = nil,
         hasMoreSongs: Bool = false,
         songsBrowseId: String? = nil,
-        songsParams: String? = nil
+        songsParams: String? = nil,
+        mixPlaylistId: String? = nil,
+        mixVideoId: String? = nil
     ) {
         self.artist = artist
         self.description = description
@@ -49,5 +55,7 @@ struct ArtistDetail: Sendable {
         self.hasMoreSongs = hasMoreSongs
         self.songsBrowseId = songsBrowseId
         self.songsParams = songsParams
+        self.mixPlaylistId = mixPlaylistId
+        self.mixVideoId = mixVideoId
     }
 }

Core/Services/API/MockUITestYTMusicClient.swift

@@ -302,6 +302,40 @@ final class MockUITestYTMusicClient: YTMusicClientProtocol {
         }
     }
 
+    func getMixQueue(playlistId: String, startVideoId _: String?) async throws -> RadioQueueResult {
+        try? await Task.sleep(for: .milliseconds(100))
+        // Return a mix queue based on the playlist ID
+        let songs = (0 ..< 50).map { index in
+            Song(
+                id: "mix-\(playlistId)-\(index)",
+                title: "Mix Song \(index + 1)",
+                artists: [Artist(id: "mix-artist-\(index % 5)", name: "Mix Artist \(index % 5 + 1)")],
+                album: nil,
+                duration: TimeInterval(180 + index * 5),
+                thumbnailURL: nil,
+                videoId: "mix-video-\(playlistId)-\(index)"
+            )
+        }
+        return RadioQueueResult(songs: songs, continuationToken: "mock-continuation-token")
+    }
+
+    func getMixQueueContinuation(continuationToken _: String) async throws -> RadioQueueResult {
+        try? await Task.sleep(for: .milliseconds(100))
+        // Return more songs for infinite mix
+        let songs = (50 ..< 75).map { index in
+            Song(
+                id: "mix-continuation-\(index)",
+                title: "Mix Song \(index + 1)",
+                artists: [Artist(id: "mix-artist-\(index % 5)", name: "Mix Artist \(index % 5 + 1)")],
+                album: nil,
+                duration: TimeInterval(180 + index * 5),
+                thumbnailURL: nil,
+                videoId: "mix-video-continuation-\(index)"
+            )
+        }
+        return RadioQueueResult(songs: songs, continuationToken: nil)
+    }
+
     func getMoodCategory(browseId _: String, params _: String?) async throws -> HomeResponse {
         try? await Task.sleep(for: .milliseconds(100))
         // Return mock mood category content

Core/Services/API/Parsers/ArtistParser.swift

@@ -74,7 +74,9 @@ enum ArtistParser {
             subscriberCount: headerResult.subscriberCount,
             hasMoreSongs: hasMoreSongs,
             songsBrowseId: songsBrowseId,
-            songsParams: songsParams
+            songsParams: songsParams,
+            mixPlaylistId: headerResult.mixPlaylistId,
+            mixVideoId: headerResult.mixVideoId
         )
     }
 
@@ -88,6 +90,8 @@ enum ArtistParser {
         var channelId: String?
         var isSubscribed: Bool = false
         var subscriberCount: String?
+        var mixPlaylistId: String?
+        var mixVideoId: String?
     }
 
     private static func parseArtistHeader(_ data: [String: Any], artistId: String) -> HeaderParseResult {
@@ -113,6 +117,9 @@ enum ArtistParser {
 
             // Parse subscription button for channel ID and subscription status
             self.parseSubscriptionButton(from: immersiveHeader, into: &result)
+
+            // Parse startRadioButton for mix (personalized radio)
+            self.parseStartRadioButton(from: immersiveHeader, into: &result)
         }
 
         // Try musicVisualHeaderRenderer (alternative header format)
@@ -129,6 +136,9 @@ enum ArtistParser {
 
             // Parse subscription button for channel ID and subscription status
             self.parseSubscriptionButton(from: visualHeader, into: &result)
+
+            // Parse startRadioButton for mix (personalized radio)
+            self.parseStartRadioButton(from: visualHeader, into: &result)
         }
 
         return result
@@ -183,6 +193,39 @@ enum ArtistParser {
         }
     }
 
+    // MARK: - Start Radio Button Parsing
+
+    /// Parses the startRadioButton to extract mix playlist ID and video ID.
+    private static func parseStartRadioButton(from header: [String: Any], into result: inout HeaderParseResult) {
+        // Look for startRadioButton in header
+        // Path: startRadioButton.buttonRenderer.navigationEndpoint.watchPlaylistEndpoint
+        guard let startRadioButton = header["startRadioButton"] as? [String: Any],
+              let buttonRenderer = startRadioButton["buttonRenderer"] as? [String: Any],
+              let navigationEndpoint = buttonRenderer["navigationEndpoint"] as? [String: Any]
+        else {
+            return
+        }
+
+        // Try watchPlaylistEndpoint first (used by artist mix buttons)
+        if let watchPlaylistEndpoint = navigationEndpoint["watchPlaylistEndpoint"] as? [String: Any] {
+            if let playlistId = watchPlaylistEndpoint["playlistId"] as? String {
+                result.mixPlaylistId = playlistId
+            }
+            // watchPlaylistEndpoint doesn't have videoId - API picks random start
+            return
+        }
+
+        // Fall back to watchEndpoint (used by some song radios)
+        if let watchEndpoint = navigationEndpoint["watchEndpoint"] as? [String: Any] {
+            if let playlistId = watchEndpoint["playlistId"] as? String {
+                result.mixPlaylistId = playlistId
+            }
+            if let videoId = watchEndpoint["videoId"] as? String {
+                result.mixVideoId = videoId
+            }
+        }
+    }
+
     // MARK: - Content Parsing
 
     /// Parses songs from artist songs browse response.

Core/Services/API/Parsers/RadioQueueParser.swift

@@ -1,11 +1,22 @@
 import Foundation
 
+// MARK: - RadioQueueResult
+
+/// Result from parsing a radio queue, including songs and continuation token.
+struct RadioQueueResult {
+    let songs: [Song]
+    /// Continuation token for fetching more songs (infinite mix).
+    let continuationToken: String?
+}
+
+// MARK: - RadioQueueParser
+
 /// Parses radio queue responses from YouTube Music API.
 enum RadioQueueParser {
     /// Parses the radio queue from the "next" endpoint response.
     /// - Parameter data: The response from the "next" endpoint with a radio playlist ID
-    /// - Returns: Array of songs in the radio queue
-    static func parse(from data: [String: Any]) -> [Song] {
+    /// - Returns: RadioQueueResult containing songs and optional continuation token
+    static func parse(from data: [String: Any]) -> RadioQueueResult {
         guard let contents = data["contents"] as? [String: Any],
               let watchNextRenderer = contents["singleColumnMusicWatchNextResultsRenderer"] as? [String: Any],
               let tabbedRenderer = watchNextRenderer["tabbedRenderer"] as? [String: Any],
@@ -19,9 +30,50 @@ enum RadioQueueParser {
               let playlistPanelRenderer = queueContent["playlistPanelRenderer"] as? [String: Any],
               let playlistContents = playlistPanelRenderer["contents"] as? [[String: Any]]
         else {
-            return []
+            return RadioQueueResult(songs: [], continuationToken: nil)
+        }
+
+        // Extract continuation token for infinite mix
+        var continuationToken: String?
+        if let continuations = playlistPanelRenderer["continuations"] as? [[String: Any]],
+           let firstContinuation = continuations.first,
+           let nextRadioData = firstContinuation["nextRadioContinuationData"] as? [String: Any],
+           let token = nextRadioData["continuation"] as? String
+        {
+            continuationToken = token
+        }
+
+        let songs = Self.parseSongs(from: playlistContents)
+        return RadioQueueResult(songs: songs, continuationToken: continuationToken)
+    }
+
+    /// Parses a continuation response for more queue items.
+    /// - Parameter data: The continuation response
+    /// - Returns: RadioQueueResult with additional songs and next continuation token
+    static func parseContinuation(from data: [String: Any]) -> RadioQueueResult {
+        guard let continuationContents = data["continuationContents"] as? [String: Any],
+              let playlistPanelContinuation = continuationContents["playlistPanelContinuation"] as? [String: Any],
+              let contents = playlistPanelContinuation["contents"] as? [[String: Any]]
+        else {
+            return RadioQueueResult(songs: [], continuationToken: nil)
         }
 
+        // Extract next continuation token
+        var continuationToken: String?
+        if let continuations = playlistPanelContinuation["continuations"] as? [[String: Any]],
+           let firstContinuation = continuations.first,
+           let nextRadioData = firstContinuation["nextRadioContinuationData"] as? [String: Any],
+           let token = nextRadioData["continuation"] as? String
+        {
+            continuationToken = token
+        }
+
+        let songs = Self.parseSongs(from: contents)
+        return RadioQueueResult(songs: songs, continuationToken: continuationToken)
+    }
+
+    /// Parses songs from playlist panel contents.
+    private static func parseSongs(from playlistContents: [[String: Any]]) -> [Song] {
         var songs: [Song] = []
         for item in playlistContents {
             // Handle both direct and wrapped renderer structures
@@ -67,8 +119,6 @@ enum RadioQueueParser {
         return songs
     }
 
-    // MARK: - Parsing Helpers
-
     /// Parses the song title from the panel video renderer.
     private static func parseTitle(from renderer: [String: Any]) -> String {
         if let titleData = renderer["title"] as? [String: Any],

Core/Services/API/YTMusicClient.swift

@@ -209,14 +209,21 @@ final class YTMusicClient: YTMusicClientProtocol {
         self.hasMoreSections(for: .podcasts)
     }
 
-    /// Makes a continuation request.
+    /// Makes a continuation request for browse endpoints.
     private func requestContinuation(_ token: String, ttl: TimeInterval? = APICache.TTL.home) async throws -> [String: Any] {
         let body: [String: Any] = [
             "continuation": token,
         ]
         return try await self.request("browse", body: body, ttl: ttl)
     }
 
+    /// Makes a continuation request for next/queue endpoints.
+    private func requestContinuation(_ token: String, body additionalBody: [String: Any]) async throws -> [String: Any] {
+        var body = additionalBody
+        body["continuation"] = token
+        return try await self.request("next", body: body)
+    }
+
     /// Searches for content.
     func search(query: String) async throws -> SearchResponse {
         self.logger.info("Searching for: \(query)")
@@ -693,9 +700,53 @@ final class YTMusicClient: YTMusicClientProtocol {
         ]
 
         let data = try await request("next", body: body)
-        let songs = RadioQueueParser.parse(from: data)
-        self.logger.info("Fetched radio queue with \(songs.count) songs")
-        return songs
+        let result = RadioQueueParser.parse(from: data)
+        self.logger.info("Fetched radio queue with \(result.songs.count) songs")
+        return result.songs
+    }
+
+    /// Fetches a mix queue from a playlist ID (e.g., artist mix "RDEM...").
+    /// Uses the "next" endpoint with the provided playlist ID.
+    /// - Parameters:
+    ///   - playlistId: The mix playlist ID (e.g., "RDEM..." for artist mix)
+    ///   - startVideoId: Optional starting video ID
+    /// - Returns: RadioQueueResult with songs and continuation token for infinite mix
+    func getMixQueue(playlistId: String, startVideoId: String?) async throws -> RadioQueueResult {
+        self.logger.info("Fetching mix queue for playlist: \(playlistId)")
+
+        var body: [String: Any] = [
+            "playlistId": playlistId,
+            "enablePersistentPlaylistPanel": true,
+            "isAudioOnly": true,
+            "tunerSettingValue": "AUTOMIX_SETTING_NORMAL",
+        ]
+
+        // Add video ID if provided to start at a specific track
+        if let videoId = startVideoId {
+            body["videoId"] = videoId
+        }
+
+        let data = try await request("next", body: body)
+        let result = RadioQueueParser.parse(from: data)
+        self.logger.info("Fetched mix queue with \(result.songs.count) songs, hasContinuation: \(result.continuationToken != nil)")
+        return result
+    }
+
+    /// Fetches more songs for a mix queue using a continuation token.
+    /// - Parameter continuationToken: The continuation token from a previous getMixQueue call
+    /// - Returns: RadioQueueResult with additional songs and next continuation token
+    func getMixQueueContinuation(continuationToken: String) async throws -> RadioQueueResult {
+        self.logger.info("Fetching mix queue continuation")
+
+        let body: [String: Any] = [
+            "enablePersistentPlaylistPanel": true,
+            "isAudioOnly": true,
+        ]
+
+        let data = try await requestContinuation(continuationToken, body: body)
+        let result = RadioQueueParser.parseContinuation(from: data)
+        self.logger.info("Fetched \(result.songs.count) more songs, hasContinuation: \(result.continuationToken != nil)")
+        return result
     }
 
     // MARK: - Song Metadata