MyQRCode/MyQrCode/ScannerView/ScannerViewModel.swift

import SwiftUI
import AVFoundation
import AudioToolbox
import Combine

// MARK: - 扫描器视图模型
class ScannerViewModel: NSObject, ObservableObject, AVCaptureMetadataOutputObjectsDelegate {
    @Published var detectedCodes: [DetectedCode] = []
    @Published var showAlert = false
    @Published var cameraAuthorizationStatus: AVAuthorizationStatus = .notDetermined
    @Published var showPermissionAlert = false
    
    var captureSession: AVCaptureSession!
    private var metadataOutput: AVCaptureMetadataOutput?
    
    override init() {
        super.init()
        checkCameraPermission()
    }
    
    // MARK: - 相机权限管理
    
    private func checkCameraPermission() {
        logInfo("🔍 检查相机权限状态", className: "ScannerViewModel")
        
        switch AVCaptureDevice.authorizationStatus(for: .video) {
        case .authorized:
            logInfo("✅ 相机权限已授权", className: "ScannerViewModel")
            cameraAuthorizationStatus = .authorized
            setupCaptureSession()
            
        case .notDetermined:
            logInfo("❓ 相机权限未确定，请求权限", className: "ScannerViewModel")
            requestCameraPermission()
            
        case .denied, .restricted:
            logWarning("❌ 相机权限被拒绝或受限", className: "ScannerViewModel")
            cameraAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: .video)
            showPermissionAlert = true
            
        @unknown default:
            logWarning("❓ 未知的相机权限状态", className: "ScannerViewModel")
            cameraAuthorizationStatus = .notDetermined
        }
    }
    
    private func requestCameraPermission() {
        logInfo("🔐 请求相机权限", className: "ScannerViewModel")
        
        AVCaptureDevice.requestAccess(for: .video) { [weak self] granted in
            DispatchQueue.main.async {
                if granted {
                    logInfo("✅ 相机权限请求成功", className: "ScannerViewModel")
                    self?.cameraAuthorizationStatus = .authorized
                    self?.setupCaptureSession()
                } else {
                    logWarning("❌ 相机权限请求被拒绝", className: "ScannerViewModel")
                    self?.cameraAuthorizationStatus = .denied
                    self?.showPermissionAlert = true
                }
            }
        }
    }
    
    func openSettings() {
        logInfo("⚙️ 打开系统设置", className: "ScannerViewModel")
        
        if let settingsUrl = URL(string: UIApplication.openSettingsURLString) {
            UIApplication.shared.open(settingsUrl) { success in
                if success {
                    logInfo("✅ 成功打开系统设置", className: "ScannerViewModel")
                } else {
                    logWarning("⚠️ 打开系统设置失败", className: "ScannerViewModel")
                }
            }
        }
    }
    
    func refreshCameraPermission() {
        logInfo("🔍 重新检查相机权限状态", className: "ScannerViewModel")
        checkCameraPermission()
    }
    
    // MARK: - 相机设置
    
    private func setupCaptureSession() {
        captureSession = AVCaptureSession()
        
        guard let videoCaptureDevice = AVCaptureDevice.default(for: .video) else {
            showAlert = true
            return
        }
        
        let videoInput: AVCaptureDeviceInput
        
        do {
            videoInput = try AVCaptureDeviceInput(device: videoCaptureDevice)
        } catch {
            showAlert = true
            return
        }
        
        if captureSession.canAddInput(videoInput) {
            captureSession.addInput(videoInput)
        } else {
            showAlert = true
            return
        }
        
        metadataOutput = AVCaptureMetadataOutput()
        
        if let metadataOutput = metadataOutput,
           captureSession.canAddOutput(metadataOutput) {
            captureSession.addOutput(metadataOutput)
            metadataOutput.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
            metadataOutput.metadataObjectTypes = [.qr, .ean8, .ean13, .code128, .code39, .upce, .pdf417, .aztec]
        } else {
            showAlert = true
            return
        }
    }
    
    // MARK: - 扫描控制
    
    func startScanning() {
        logInfo("🔄 开始扫描", className: "ScannerViewModel")
        
        // 检查会话是否已经在运行
        if captureSession?.isRunning == true {
            logInfo("ℹ️ 扫描会话已经在运行", className: "ScannerViewModel")
            return
        }
        
        DispatchQueue.global(qos: .userInitiated).async { [weak self] in
            guard let self = self else { return }
            
            self.captureSession?.startRunning()
            
            // 检查启动状态
            DispatchQueue.main.asyncAfter(deadline: .now() + 0.2) {
                if self.captureSession?.isRunning == true {
                    logInfo("✅ 扫描会话启动成功", className: "ScannerViewModel")
                } else {
                    logWarning("⚠️ 扫描会话启动失败", className: "ScannerViewModel")
                }
            }
        }
    }
    
    func stopScanning() {
        logInfo("🔄 停止扫描", className: "ScannerViewModel")
        
        // 检查会话是否在运行
        if captureSession?.isRunning == true {
            DispatchQueue.global(qos: .userInitiated).async { [weak self] in
                self?.captureSession?.stopRunning()
                
                DispatchQueue.main.async {
                    logInfo("✅ 扫描会话已停止", className: "ScannerViewModel")
                }
            }
        } else {
            logInfo("ℹ️ 扫描会话已经停止", className: "ScannerViewModel")
        }
    }
    
    func resetDetection() {
        DispatchQueue.main.async {
            logInfo("🔄 重置检测状态，清空 detectedCodes", className: "ScannerViewModel")
            self.detectedCodes = []
        }
    }
    
    func isSessionRunning() -> Bool {
        return captureSession?.isRunning == true
    }
    
    func checkSessionStatus() {
        let isRunning = captureSession?.isRunning == true
        logInfo("📊 扫描会话状态检查: \(isRunning ? "运行中" : "已停止")", className: "ScannerViewModel")
        
        if !isRunning {
            logWarning("⚠️ 扫描会话未运行，尝试重新启动", className: "ScannerViewModel")
            startScanning()
        }
    }
    
    func restartScanning() {
        logInfo("🔄 重新开始扫描", className: "ScannerViewModel")
        
        // 确保在主线程执行UI相关操作
        DispatchQueue.main.async { [weak self] in
            guard let self = self else { return }
            
            // 先停止当前会话
            if self.captureSession?.isRunning == true {
                logInfo("🔄 停止当前运行的扫描会话", className: "ScannerViewModel")
                self.captureSession?.stopRunning()
            }
            
            // 重置检测状态
            self.detectedCodes = []
            
            // 延迟后重新启动会话
            DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
                
                logInfo("🔄 准备重新启动扫描会话", className: "ScannerViewModel")
                
                // 在后台线程启动会话
                DispatchQueue.global(qos: .userInitiated).async {
                    self.captureSession?.startRunning()
                    
                    // 检查会话状态
                    DispatchQueue.main.asyncAfter(deadline: .now() + 0.2) {
                        if self.captureSession?.isRunning == true {
                            logInfo("✅ 扫描会话已成功重新启动", className: "ScannerViewModel")
                        } else {
                            logWarning("⚠️ 扫描会话启动失败，尝试重新启动", className: "ScannerViewModel")
                            // 如果启动失败，再次尝试
                            DispatchQueue.global(qos: .userInitiated).async {
                                self.captureSession?.startRunning()
                                DispatchQueue.main.async {
                                    if self.captureSession?.isRunning == true {
                                        logInfo("✅ 扫描会话第二次尝试启动成功", className: "ScannerViewModel")
                                    } else {
                                        logError("❌ 扫描会话启动失败", className: "ScannerViewModel")
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
    
    // MARK: - AVCaptureMetadataOutputObjectsDelegate
    
    func metadataOutput(_ output: AVCaptureMetadataOutput, 
                       didOutput metadataObjects: [AVMetadataObject], 
                       from connection: AVCaptureConnection) {
        
        logInfo("metadataOutput 被调用，检测到 \(metadataObjects.count) 个对象", className: "ScannerViewModel")
        
        // 震动反馈
        AudioServicesPlaySystemSound(SystemSoundID(kSystemSoundID_Vibrate))
        
        // 停止扫描
        stopScanning()
        
        // 处理所有检测到的条码
        var codes: [DetectedCode] = []
        
        for metadataObject in metadataObjects {
            if let readableObject = metadataObject as? AVMetadataMachineReadableCodeObject,
               let stringValue = readableObject.stringValue {
                
                let codeType = readableObject.type.rawValue
                let bounds = readableObject.bounds
                
                let detectedCode = DetectedCode(
                    type: codeType,
                    content: stringValue,
                    bounds: bounds
                )
                
                codes.append(detectedCode)
                logInfo("创建 DetectedCode: 类型=\(codeType), 内容=\(stringValue)", className: "ScannerViewModel")
            }
        }
        
        logInfo("准备更新 detectedCodes，数量: \(codes.count)", className: "ScannerViewModel")
        
        // 更新检测到的条码列表
        DispatchQueue.main.async {
            logInfo("在主线程更新 detectedCodes", className: "ScannerViewModel")
            self.detectedCodes = codes
        }
    }
}