//
//  KMResourceDownloadManager.swift
//  PDF Reader Pro
//
//  Created by lizhe on 2023/8/29.
//

import Cocoa
import Foundation
import ZipArchive // 请确保已导入 SSZipArchive 或其他合适的解压库
import ComDocumentAIKit
import ComPDFKit_Conversion

//#if DEBUG
//let xmlURLString = "http://test-pdf-pro.kdan.cn:3021/downloads/DocumentAI.xml"
//#else
//let xmlURLString = "https://www.pdfreaderpro.com/downloads/DocumentAI.xml"
//#endif
//let documentAIString = "http://test-pdf-pro.kdan.cn:3021/downloads/DocumentAI.bundle.zip"
let xmlURLString = KMServerConfig().kResourceServerURL
let kResourcePath: String = kAppSupportOfBundleIdentifierDirectory.path
let kLocalFilePath: String = kAppSupportOfBundleIdentifierDirectory.appendingPathComponent("DocumentAI.bundle").path

enum KMResourceDownloadState {
    case none
    case unzipFailed
    case moveFailed
    case success
    case retry
    case cancel
}

struct Version: Comparable {
    let components: [Int]
    
    init?(_ version: String) {
        components = version.split(separator: ".").compactMap { Int($0) }
        guard !components.isEmpty else { return nil }
    }
    
    static func < (lhs: Version, rhs: Version) -> Bool {
        for (l, r) in zip(lhs.components, rhs.components) {
            if l != r { return l < r }
        }
        return lhs.components.count < rhs.components.count
    }
}

class KMResourceDownloadManager: NSObject {
    static let manager = KMResourceDownloadManager()
    
    var downloadTask: URLSessionDownloadTask?
    var progressBlock: ((Double) -> Void)?
    var downloadResultBlock: ((Bool, KMResourceDownloadState) -> Void)?
    var reachabilityAlert: NSAlert?
    
    
    func downloadFramework(progress: @escaping (Double) -> Void, result: @escaping (Bool, KMResourceDownloadState) -> Void) {
        self.progressBlock = progress
        self.downloadResultBlock = result
        
        KMRequestServer.requestServer.reachabilityStatusChange { [weak self] status in
            if status == .notReachable {
                KMPrint("无网络")
                self?.downloadTask?.cancel()
                self?.downloadTask = nil
                self?.downloadResultBlock?(false, .none)
                DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 0.2, execute: { [weak self] in
                    if self?.reachabilityAlert == nil {
                        self?.reachabilityAlert = NSAlert()
                        self?.reachabilityAlert?.messageText = NSLocalizedString("Network Disconnected", comment: "")
                        self?.reachabilityAlert?.informativeText = NSLocalizedString("Please connect to the internet and download again.", comment: "")
                        self?.reachabilityAlert?.addButton(withTitle: NSLocalizedString("Retry", comment: ""))
                        self?.reachabilityAlert?.addButton(withTitle: NSLocalizedString("Cancel", comment: ""))
                        var window = NSWindow.currentWindow()
                        if window != nil {
                            self?.reachabilityAlert?.beginSheetModal(for: window) { result in
                                if (result == .alertSecondButtonReturn) {
                                    self?.reachabilityAlert = nil

                                    self?.cancelDownload()
                                } else if result == .alertFirstButtonReturn {
                                    self?.reachabilityAlert = nil
                                    self?.downloadResultBlock?(false, .retry)
                                    self?.cancelDownload()
                                    return
                                }
                                self?.reachabilityAlert = nil
                            }
                        } else {
                            self?.reachabilityAlert = nil
                        }
                    } else {
                        self?.reachabilityAlert = nil
                    }
                })
            } else {
                KMPrint("有网络")
            }
        }
        
        if self.downloadTask == nil {
            self.downloadXML { [unowned self] content in
                let urlString = self.dealXML(content: content)
    //            let urlString = "http://test-pdf-pro.kdan.cn:3021/downloads/DocumentAI.bundle.zip"
                if let url = URL(string: urlString) {
                    let configuration = URLSessionConfiguration.default
                    let session = URLSession(configuration: configuration, delegate: self, delegateQueue: nil)
                    let downloadTask = session.downloadTask(with: url)
                    downloadTask.resume()
                    self.downloadTask = downloadTask
                } else {
                    dealDownloadResult(isSuccess: false, state: .none)
                }
            }
        } else {
            dealDownloadResult(isSuccess: false, state: .none)
        }
    }
    
    func documentAIBundleExists(complete:@escaping (_ result: Bool) -> Void) {
        let filePath: String = kLocalFilePath
        let fileManager = FileManager.default
        debugPrint(filePath)
        debugPrint(FileManager.default.temporaryDirectory.appendingPathComponent("XMLResources"))
        let exists = fileManager.fileExists(atPath: filePath as String)
        //如果存在则判断版本是否符合，如果不符合则删除后重新下载
        if exists {
            self.checkDocumentAIVersion(complete: complete)
            self.loadDocumentAIBundle(bundlePath: kLocalFilePath)
        } else {
            self.removeDownloadResourcePath()
            complete(false)
        }
    }
    
    func cancelDownload() {
        downloadTask?.cancel()
        downloadTask = nil
        progressBlock = nil
        downloadResultBlock = nil
        
        self.downloadResultBlock?(false, .cancel)
    }
    
    //结果处理
    func dealDownloadResult(isSuccess: Bool, state: KMResourceDownloadState) {
        DispatchQueue.main.async {
            self.downloadResultBlock?(isSuccess, state)
            self.cancelDownload()
        }
    }
    
    func checkDocumentAIVersion(complete: @escaping (_ results: Bool) -> Void) {
        self.downloadXML { [unowned self] content in
            let urlString = self.dealXML(content: content)
            if urlString.count != 0 {
                try?FileManager.default.removeItem(atPath: kLocalFilePath)
                
                complete(false)
            } else {
                complete(true)
            }
        }
    }
    
    func loadDocumentAIBundle(bundlePath: String) {
        guard FileManager.default.fileExists(atPath: bundlePath) else {
            print("Bundle does not exist at specified path.")
            return
        }
        
        if let bundle = Bundle(path: bundlePath) {
            if let resourcePath = bundle.path(forResource: "DocumentAI", ofType: "model") {
                print("Found resource at path: \(resourcePath)")
                //绑定资源包
                CDocumentAIKit.sharedInstance().setOCRModelPath(bundlePath)
                CPDFConvertKit.setOCRModelPath(bundlePath)
            } else {
                print("Resource not found.")
            }
        } else {
            print("Failed to load bundle.")
        }
    }
}

//MARK: UI
extension KMResourceDownloadManager {
    func downLoadOCRResource(window: NSWindow) {
#if VERSION_DMG
        DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 0.3) {
            KMResourceDownloadManager.manager.documentAIBundleExists(complete: { [weak self] result in
                if result {
                    
                } else {
                    let alert = NSAlert()
                    alert.alertStyle = .critical
                    alert.messageText = KMLocalizedString("Need DownLoad OCR Resource", comment: "")
                    alert.addButton(withTitle: KMLocalizedString("OK", comment: ""))
                    alert.addButton(withTitle: KMLocalizedString("Cancel", comment: ""))
                    alert.beginSheetModal(for: NSWindow.currentWindow()) {[weak self] response in
                        if response == NSApplication.ModalResponse.alertFirstButtonReturn {
                            self?.downLoad(window: window)
                        }
                    }
                }
            })
        }
#endif
    }
    
#if VERSION_DMG
    func downLoad(window: NSWindow) {
        let controller = KMOCRDownloadViewController(nibName: "KMOCRDownloadViewController", bundle: nil)
        let tempWindow = NSWindow(contentViewController: controller)
        tempWindow.maxSize = CGSizeMake(480, 208)
        tempWindow.minSize = CGSizeMake(480, 208)
        tempWindow.styleMask.remove(.resizable)
        window.beginSheet(tempWindow)
        
        controller.closeAction = { [unowned self] controller2 in
            window.endSheet(tempWindow)
        }
        
        controller.completionAction = { [unowned self] controller2 in
            window.endSheet(tempWindow)
        }
        
        controller.begin()
    }
#endif
}

extension KMResourceDownloadManager: XMLParserDelegate {
    func downloadXML(completion: @escaping (_ content: String) -> Void) {
        if let xmlURL = URL(string: xmlURLString) {
            let request = URLRequest(url: xmlURL)
            let session = URLSession.shared
            let task = session.dataTask(with: request) { (data, response, error) in
                if let error = error {
                    print("Error: \(error)")
                } else if let data = data {
                    if let xmlString = String(data: data, encoding: .utf8) {
                        print("XML Data: \(xmlString)")
                        completion(xmlString)
                    }
                }
            }
            task.resume()
        } else {
            print("Invalid URL")
            completion("")
        }
    }
    
    func dealXML(content: String) -> String {
//
        // 1. 定义 XML 内容，包括版本号
//        let xmlContent = """
//        <root>
//            <resources>
//                <resource>
//                    <maxVersion>1.3.0</maxVersion>
//                    <minVersion>1.1.0</minVersion>
//                    <resourceURL>https://www.pdfreaderpro.com/downloads/DocumentAI.bundle.1.0.0.zip</resourceURL>
//                </resource>
//                <resource>
//                    <maxVersion>4.6.3</maxVersion>
//                    <minVersion>1.4.0</minVersion>
//                    <resourceURL>https://www.pdfreaderpro.com/downloads/DocumentAI.bundle.2.0.0.zip</resourceURL>
//                </resource>
//            </resources>
//        </root>
//        """
        let xmlContent = content
        
        let parser = ResourceParser()
        let resources = parser.parse(data: xmlContent.data(using: .utf8)!)
        
        // 从捆绑包的 Info.plist 文件中获取版本号
        var appVersion = "1.0.0"
        if let version = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String {
            appVersion = version
            print("应用程序版本号：\(appVersion)")
        } else {
            print("无法获取应用程序版本号。")
        }

        if let resourceURL = shouldDownloadResource(for: appVersion, resources: resources) {
            if let local = self.getDownloadedResourcePath(for: kLocalFilePath) {
                if local != resourceURL {
                    //如果本地存在两个地址不相同 则下载
                    print("No suitable resource found for the current version.")
                    return resourceURL
                } else {
                    //如果本地存在 两个地址相同 则不下载
                    print("No suitable resource found for the current version.")
                    return ""
                }
            } else {
                //如果本地不存在 则下载
                print("Download resource from: \(resourceURL)")
                return resourceURL
            }
        } else {
            //如果找不到下载链接 则不下载
            print("No suitable resource found for the current version.")
            return ""
        }
    }
    
    func shouldDownloadResource(for currentVersion: String, resources: [Resource]) -> String? {
        for resource in resources {
            if isVersion(currentVersion, between: resource.minVersion, and: resource.maxVersion) {
                return resource.resourceURL
            }
        }
        return nil
    }

    func isVersion(_ version: String, between minVersion: String, and maxVersion: String) -> Bool {
        guard let current = Version(version),
              let min = Version(minVersion),
              let max = Version(maxVersion) else {
            return false
        }
        return current >= min && current <= max
    }
    
    func saveDownloadedResource(resourceURL: String, localPath: String) {
        var resources = UserDefaults.standard.dictionary(forKey: "downloadedResources") as? [String: String] ?? [:]
        resources[localPath] = resourceURL
        UserDefaults.standard.set(resources, forKey: "downloadedResources")
    }
    
    func getDownloadedResourcePath(for resourceURL: String) -> String? {
        let resources = UserDefaults.standard.dictionary(forKey: "downloadedResources") as? [String: String]
        return resources?[resourceURL]
    }
    
    func removeDownloadResourcePath() {
        UserDefaults.standard.removeObject(forKey: "downloadedResources")
    }
    
    func validateResource(for resourceURL: String) -> Bool {
        if let localPath = getDownloadedResourcePath(for: resourceURL) {
            return FileManager.default.fileExists(atPath: localPath)
        }
        return false
    }
}

extension KMResourceDownloadManager {
    //MARK: 解压
    func unzipFramework(at zipURL: URL, to destinationPath: String) {
        let fileManager = FileManager.default
        var success = false

        if zipURL.pathExtension == "zip" {
            success = SSZipArchive.unzipFile(atPath: zipURL.path, toDestination: destinationPath)
        } else {
            // 如果是其他类型的压缩文件，可以使用其他解压库
            // success = YourCustomUnzipLibrary.unzipFile(atPath: zipURL.path, toDestination: destinationPath)
        }
        
        if success {
            print("File unzipped successfully!")
            try? fileManager.removeItem(at: zipURL)
        } else {
            print("Failed to unzip file.")
            dealDownloadResult(isSuccess: false, state: .unzipFailed)
        }
    }
}

extension KMResourceDownloadManager: URLSessionDelegate, URLSessionDownloadDelegate {
    //MARK: 网络下载
    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didWriteData bytesWritten: Int64, totalBytesWritten: Int64, totalBytesExpectedToWrite: Int64) {
        let progress = Double(totalBytesWritten) / Double(totalBytesExpectedToWrite)
        print("Download progress: \(progress)")
        progressBlock?(progress)
    }
    
    func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {
        let destinationPath = kResourcePath
        
        let fileManager = FileManager.default
        let destinationURL = URL(fileURLWithPath: destinationPath).appendingPathComponent("DocumentAI.bundle.zip")
        
        do {
            try fileManager.moveItem(at: location, to: destinationURL)
            print("Framework downloaded and installed successfully!")
            unzipFramework(at: destinationURL, to: destinationPath)
            dealDownloadResult(isSuccess: true, state: .success)
            if let sourceURL = downloadTask.originalRequest?.url {
                saveDownloadedResource(resourceURL: sourceURL.absoluteString, localPath: kLocalFilePath)
            }
        } catch {
            print("Failed to move framework: \(error)")
            dealDownloadResult(isSuccess: false, state: .moveFailed)
        }
    }
}

struct Resource {
    let maxVersion: String
    let minVersion: String
    let resourceURL: String
}

// 5. 定义一个 XML 解析器的代理类
class ResourceParser: NSObject, XMLParserDelegate {
    private var resources: [Resource] = []
    private var currentElement = ""
    var currentMaxVersion = ""
    var currentMinVersion = ""
    var currentResourceURL = ""
    
    func parse(data: Data) -> [Resource] {
        let parser = XMLParser(data: data)
        parser.delegate = self
        parser.parse()
        return resources
    }
    
    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String] = [:]) {
        currentElement = elementName
    }
    
    func parser(_ parser: XMLParser, foundCharacters string: String) {
        switch currentElement {
        case "maxVersion":
            currentMaxVersion += string
        case "minVersion":
            currentMinVersion += string
        case "resourceURL":
            currentResourceURL += string
        default:
            break
        }
    }
    
    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        if elementName == "resource" {
            resources.append(
                Resource(
                    maxVersion: currentMaxVersion.trimmingCharacters(in: .whitespacesAndNewlines),
                    minVersion: currentMinVersion.trimmingCharacters(in: .whitespacesAndNewlines),
                    resourceURL: currentResourceURL.trimmingCharacters(in: .whitespacesAndNewlines)
                )
            )
            currentMaxVersion = ""
            currentMinVersion = ""
            currentResourceURL = ""
        }
    }
}