// // NCViewerDocumentWeb.swift // Nextcloud // // Created by Marino Faggiana on 28/09/2018. // Copyright © 2018 Marino Faggiana. All rights reserved. // // Author Marino Faggiana // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program. If not, see . // import Foundation import WebKit class NCViewerDocumentWeb: NSObject { let appDelegate = UIApplication.shared.delegate as! AppDelegate var safeAreaBottom: Int = 0 var mimeType: String? @objc static let sharedInstance: NCViewerDocumentWeb = { let instance = NCViewerDocumentWeb() return instance }() @objc func viewDocumentWebAt(_ metadata: tableMetadata, view: UIView) { if !CCUtility.fileProviderStorageExists(metadata.ocId, fileNameView: metadata.fileNameView) { return } if #available(iOS 11.0, *) { safeAreaBottom = Int((UIApplication.shared.keyWindow?.safeAreaInsets.bottom)!) } let fileNamePath = NSTemporaryDirectory() + metadata.fileNameView let fileNameExtension = (metadata.fileNameView as NSString).pathExtension.uppercased() CCUtility.copyFile(atPath: CCUtility.getDirectoryProviderStorageOcId(metadata.ocId, fileNameView: metadata.fileNameView), toPath: fileNamePath) let url = URL.init(fileURLWithPath: fileNamePath) let preferences = WKPreferences() let configuration = WKWebViewConfiguration() preferences.javaScriptEnabled = false // Detect file xls, xlss for enable javascript if fileNameExtension == "XLS" || fileNameExtension == "XLSX" { if let fileHandle = FileHandle(forReadingAtPath: fileNamePath) { let data = fileHandle.readData(ofLength: 4) if data.starts(with: [0x50, 0x4b, 0x03, 0x04]) { // "PK\003\004" preferences.javaScriptEnabled = true } fileHandle.closeFile() } } configuration.preferences = preferences let webView = WKWebView(frame: view.frame) webView.navigationDelegate = self webView.autoresizingMask = [.flexibleWidth, .flexibleHeight] webView.backgroundColor = .white webView.isOpaque = false if fileNameExtension == "CSS" || fileNameExtension == "PY" || fileNameExtension == "XML" || fileNameExtension == "JS" { do { let dataFile = try String(contentsOf: url, encoding: String.Encoding(rawValue: String.Encoding.ascii.rawValue)) if UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.phone { webView.loadHTMLString("
" + dataFile, baseURL: nil)
                } else {
                    webView.loadHTMLString("
" + dataFile, baseURL: nil)
                }
                
            } catch {
                print("error")
            }
            
        } else if CCUtility.isDocumentModifiableExtension(fileNameExtension) {
            
            let session = URLSession(configuration: URLSessionConfiguration.default)
            var request = URLRequest(url: url)
            request.httpMethod = "HEAD"
            
            let task = session.dataTask(with: request) { (data, response, error) in
                
                guard let data = data else {
                    return
                }
                guard let response = response else {
                    return
                }
                
                DispatchQueue.main.async {
                    
                    guard let encodingName = NCUchardet.sharedNUCharDet()?.encodingStringDetect(with: data) else {
                        return
                    }
                    self.mimeType = response.mimeType
                    webView.load(data, mimeType: response.mimeType!, characterEncodingName: encodingName, baseURL: url)
                }
            }
            
            task.resume()
            
        } else {
            
            webView.load(URLRequest(url: url))
        }
        
        view.addSubview(webView)
    }
}

extension NCViewerDocumentWeb: WKNavigationDelegate {
    
    public func webView(_ webView: WKWebView, didReceive challenge: URLAuthenticationChallenge, completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void) {
        if let serverTrust = challenge.protectionSpace.serverTrust {
            completionHandler(Foundation.URLSession.AuthChallengeDisposition.useCredential, URLCredential(trust: serverTrust))
        } else {
            completionHandler(URLSession.AuthChallengeDisposition.useCredential, nil);
        }
    }
    
    public func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        decisionHandler(.allow)
    }
    
    public func webView(_ webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
        print("didStartProvisionalNavigation");
    }
    
    public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        if self.mimeType != nil && self.mimeType == "text/plain" && CCUtility.getDarkMode() {
            let js = "document.getElementsByTagName('body')[0].style.webkitTextFillColor= 'white';DOMReady();"
            webView.evaluateJavaScript(js) { (_, _) in }
        }
    }
    
    public func webView(_ webView: WKWebView, didReceiveServerRedirectForProvisionalNavigation navigation: WKNavigation!) {
        print("didReceiveServerRedirectForProvisionalNavigation");
    }
}