Added in-app fileviewer for images and pdf files

lib/view/pages/files/fileElement.dart

@@ -11,6 +11,7 @@ import 'package:path_provider/path_provider.dart';
 import '../../../api/marianumcloud/webdav/queries/listFiles/cacheableFile.dart';
 import '../../../api/marianumcloud/webdav/webdavApi.dart';
 import '../../../widget/confirmDialog.dart';
+import '../../../widget/fileViewer.dart';
 import '../../../widget/unimplementedDialog.dart';
 import 'files.dart';
 
@@ -20,8 +21,8 @@ class FileElement extends StatefulWidget {
   final void Function() refetch;
   const FileElement(this.file, this.path, this.refetch, {Key? key}) : super(key: key);
 
-  static Future<DownloaderCore> download(String remotePath, String name, Function(double) onProgress, Function(OpenResult) onDone) async {
-    Directory paths = await getApplicationDocumentsDirectory();
+  static Future<DownloaderCore> download(BuildContext context, String remotePath, String name, Function(double) onProgress, Function(OpenResult) onDone) async {
+    Directory paths = await getTemporaryDirectory();
 
     String local = paths.path + Platform.pathSeparator + name;
 
@@ -34,11 +35,12 @@ class FileElement extends StatefulWidget {
       progress: ProgressImplementation(),
       deleteOnCancel: true,
       onDone: () {
-        Future<OpenResult> result = OpenFile.open(local);
-
-        result.then((value) => {
-          onDone(value)
-        });
+        //Future<OpenResult> result = OpenFile.open(local); // TODO legacy - refactor remove
+        Navigator.of(context).push(MaterialPageRoute(builder: (context) => FileViewer(path: local)));
+        onDone(OpenResult(message: "File viewer opened", type: ResultType.done));
+        // result.then((value) => {
+        //   onDone(value)
+        // });
       },
     );
 
@@ -125,7 +127,7 @@ class _FileElementState extends State<FileElement> {
 
           log("Download: ${widget.file.path} to ${widget.file.name}");
 
-          downloadCore = FileElement.download(widget.file.path, widget.file.name, (progress) {
+          downloadCore = FileElement.download(context, widget.file.path, widget.file.name, (progress) {
             setState(() => percent = progress);
           }, (result) {
             if(result.type != ResultType.done) {

lib/view/pages/talk/chatBubble.dart

@@ -235,7 +235,7 @@ class _ChatBubbleState extends State<ChatBubble> {
         }
 
         downloadProgress = 1;
-        downloadCore = FileElement.download(message.file!.path!, message.file!.name, (progress) {
+        downloadCore = FileElement.download(context, message.file!.path!, message.file!.name, (progress) {
           if(progress > 1) {
             setState(() {
               downloadProgress = progress;

lib/widget/fileViewer.dart

@@ -0,0 +1,66 @@
+import 'dart:io';
+
+import 'package:better_open_file/better_open_file.dart';
+import 'package:flutter/material.dart';
+import 'package:photo_view/photo_view.dart';
+import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
+
+import 'confirmDialog.dart';
+import 'placeholderView.dart';
+
+class FileViewer extends StatelessWidget {
+  final String path;
+  final bool openExternal;
+  const FileViewer({super.key, required this.path, this.openExternal = false});
+
+
+  @override
+  Widget build(BuildContext context) {
+    AppBar appbar = AppBar(
+      title: Text(path.split("/").last),
+      actions: [
+        IconButton(onPressed: () => ConfirmDialog(
+          title: "Extern öffnen",
+          content: "Möchtest du die Datei mit dem Systemdialog öffnen?",
+          onConfirm: () => Navigator.of(context).push(MaterialPageRoute(builder: (context) => FileViewer(path: path, openExternal: true))),
+          confirmButton: "Öffnen",
+        ).asDialog(context), icon: const Icon(Icons.open_in_new))
+      ],
+    );
+    switch(openExternal ? "x" : path.split(".").last) {
+      case "png":
+      case "jpg":
+      case "jpeg":
+        return Scaffold(
+            appBar: appbar,
+            backgroundColor: Colors.white,
+            body: PhotoView(
+              imageProvider: Image.file(File(path)).image,
+              backgroundDecoration: const BoxDecoration(color: Colors.white60),
+            )
+        );
+
+
+      case "pdf":
+        return Scaffold(
+          appBar: appbar,
+          body: SfPdfViewer.file(
+            File(path),
+          ),
+        );
+
+      default:
+        OpenFile.open(path).then((result) {
+          Navigator.of(context).pop();
+          if(result.type != ResultType.done) {
+            showDialog(context: context, builder: (context) {
+              return AlertDialog(
+                content: Text(result.message),
+              );
+            });
+          }
+        });
+        return const PlaceholderView(text: "Datei wird extern geöffnet...", icon: Icons.open_in_new);
+    }
+  }
+}