Initial commit: suixinkan_ios UIKit rewrite project.

Co-authored-by: Cursor <cursoragent@cursor.com>

suixinkan_ios/Features/Live/ViewModels/LivePlaybackViewModel.swift

@@ -0,0 +1,131 @@
+//
+//  LivePlaybackViewModel.swift
+//  suixinkan
+//
+//  Created by Codex on 2026/6/25.
+//
+
+import AVFoundation
+import Foundation
+
+/// 直播播放地址解析器，避免把 RTMP 推流地址误当作播放地址。
+enum LivePlaybackURLResolver {
+    static func playableURL(from live: LiveEntity) -> URL? {
+        playableURL(from: live.playbackURLCandidates)
+    }
+
+    static func playableURL(from candidates: [String]) -> URL? {
+        for candidate in candidates {
+            if let url = playableURL(from: candidate) {
+                return url
+            }
+        }
+        return nil
+    }
+
+    static func playableURL(from rawValue: String) -> URL? {
+        let value = rawValue.liveTrimmed
+        guard !value.isEmpty, let url = URL(string: value) else { return nil }
+        guard let scheme = url.scheme?.lowercased(), scheme == "http" || scheme == "https" else { return nil }
+        if url.pathExtension.lowercased() == "flv" {
+            return nil
+        }
+        return url
+    }
+}
+
+/// 播放器状态。
+enum LivePlaybackState: Equatable {
+    case empty
+    case ready(URL)
+    case playing(URL)
+    case failed(String)
+}
+
+@MainActor
+/// 直播播放器 ViewModel，管理系统播放器的 URL、播放和释放状态。
+final class LivePlaybackViewModel {
+    var onChange: (() -> Void)?
+    var state: LivePlaybackState = .empty { didSet { onChange?() } }
+    var errorMessage: String? { didSet { onChange?() } }
+
+    private(set) var player: AVPlayer? { didSet { onChange?() } }
+
+    var playableURL: URL? {
+        switch state {
+        case .ready(let url), .playing(let url):
+            url
+        case .empty, .failed:
+            nil
+        }
+    }
+
+    var isPlaying: Bool {
+        if case .playing = state { return true }
+        return false
+    }
+
+    init(live: LiveEntity? = nil, urlString: String? = nil) {
+        if let live {
+            load(live: live)
+        } else if let urlString {
+            load(urlString: urlString)
+        }
+    }
+
+    func load(live: LiveEntity) {
+        load(url: LivePlaybackURLResolver.playableURL(from: live))
+    }
+
+    func load(urlString: String) {
+        load(url: LivePlaybackURLResolver.playableURL(from: urlString))
+    }
+
+    func play() {
+        guard let url = playableURL else { return }
+        if player == nil {
+            player = AVPlayer(url: url)
+        }
+        player?.play()
+        state = .playing(url)
+    }
+
+    func pause() {
+        guard let url = playableURL else { return }
+        player?.pause()
+        state = .ready(url)
+    }
+
+    func reload() {
+        guard let url = playableURL else { return }
+        releasePlayer()
+        player = AVPlayer(url: url)
+        state = .ready(url)
+    }
+
+    func release() {
+        releasePlayer()
+        if let url = playableURL {
+            state = .ready(url)
+        } else {
+            state = .empty
+        }
+    }
+
+    private func load(url: URL?) {
+        releasePlayer()
+        guard let url else {
+            errorMessage = "暂无可播放地址"
+            state = .empty
+            return
+        }
+        errorMessage = nil
+        player = AVPlayer(url: url)
+        state = .ready(url)
+    }
+
+    private func releasePlayer() {
+        player?.pause()
+        player = nil
+    }
+}