support 7z;

fix #137

lib/pages/home_page.dart

@@ -453,15 +453,15 @@ class _ImportComicsWidgetState extends State<_ImportComicsWidget> {
     String info = [
       "Select a directory which contains the comic files.".tl,
       "Select a directory which contains the comic directories.".tl,
-      "Select a cbz/zip file.".tl,
-      "Select a directory which contains multiple cbz/zip files.".tl,
+      "Select an archive file (cbz, zip, 7z, cb7)".tl,
+      "Select a directory which contains multiple archive files.".tl,
       "Select an EhViewer database and a download folder.".tl
     ][type];
     List<String> importMethods = [
       "Single Comic".tl,
       "Multiple Comics".tl,
-      "A cbz file".tl,
-      "Multiple cbz files".tl,
+      "An archive file".tl,
+      "Multiple archive files".tl,
       "EhViewer downloads".tl
     ];
 
@@ -493,7 +493,7 @@ class _ImportComicsWidgetState extends State<_ImportComicsWidget> {
                     },
                   );
                 }),
-                if (type != 3)
+                if (type != 4)
                   ListTile(
                     title: Text("Add to favorites".tl),
                     trailing: Select(
@@ -507,7 +507,7 @@ class _ImportComicsWidgetState extends State<_ImportComicsWidget> {
                       },
                     ),
                   ).paddingHorizontal(8),
-                if (!App.isIOS && !App.isMacOS)
+                if (!App.isIOS && !App.isMacOS && type != 2 && type != 3)
                   CheckboxListTile(
                       enabled: true,
                       title: Text("Copy to app local path".tl),

lib/utils/cbz.dart

@@ -1,9 +1,10 @@
 import 'dart:convert';
-
+import 'package:flutter_7zip/flutter_7zip.dart';
 import 'package:venera/foundation/app.dart';
 import 'package:venera/foundation/comic_type.dart';
 import 'package:venera/foundation/local.dart';
 import 'package:venera/utils/ext.dart';
+import 'package:venera/utils/file_type.dart';
 import 'package:venera/utils/io.dart';
 import 'package:zip_flutter/zip_flutter.dart';
 
@@ -57,12 +58,33 @@ class ComicChapter {
   ComicChapter({required this.title, required this.start, required this.end});
 }
 
+/// Comic Book Archive. Currently supports CBZ, ZIP and 7Z formats.
 abstract class CBZ {
+  static Future<FileType> checkType(File file) async {
+    var header = <int>[];
+    await for (var bytes in file.openRead()) {
+      header.addAll(bytes);
+      if (header.length >= 32) break;
+    }
+    return detectFileType(header);
+  }
+
+  static Future<void> extractArchive(File file, Directory out) async {
+    var fileType = await checkType(file);
+    if (fileType.mime == 'application/zip') {
+      await ZipFile.openAndExtractAsync(file.path, out.path, 4);
+    } else if (fileType.mime == "application/x-7z-compressed") {
+      await SZArchive.extractIsolates(file.path, out.path, 4);
+    } else {
+      throw Exception('Unsupported archive type');
+    }
+  }
+
   static Future<LocalComic> import(File file) async {
     var cache = Directory(FilePath.join(App.cachePath, 'cbz_import'));
     if (cache.existsSync()) cache.deleteSync(recursive: true);
     cache.createSync();
-    await ZipFile.openAndExtractAsync(file.path, cache.path, 4);
+    await extractArchive(file, cache);
     var metaDataFile = File(FilePath.join(cache.path, 'metadata.json'));
     ComicMetaData? metaData;
     if (metaDataFile.existsSync()) {
@@ -72,7 +94,7 @@ abstract class CBZ {
       } catch (_) {}
     }
     metaData ??= ComicMetaData(
-      title: file.name.replaceLast('.cbz', ''),
+      title: file.name.substring(0, file.name.lastIndexOf('.')),
       author: "",
       tags: [],
     );
@@ -86,6 +108,7 @@ abstract class CBZ {
       return !['jpg', 'jpeg', 'png', 'webp', 'gif', 'jpe'].contains(ext);
     });
     if(files.isEmpty) {
+      cache.deleteSync(recursive: true);
       throw Exception('No images found in the archive');
     }
     files.sort((a, b) => a.path.compareTo(b.path));

lib/utils/file_type.dart

@@ -21,8 +21,17 @@ class FileType {
   }
 }
 
+final _resolver = MimeTypeResolver()
+  // zip
+  ..addMagicNumber([0x50, 0x4B], 'application/zip')
+  // 7z
+  ..addMagicNumber([0x37, 0x7A, 0xBC, 0xAF, 0x27, 0x1C], 'application/x-7z-compressed')
+  // rar
+  ..addMagicNumber([0x52, 0x61, 0x72, 0x21, 0x1A, 0x07], 'application/vnd.rar')
+;
+
 FileType detectFileType(List<int> data) {
-  var mime = lookupMimeType('no-file', headerBytes: data);
+  var mime = _resolver.lookup('no-file', headerBytes: data);
   var ext = mime == null ? '' : extensionFromMime(mime);
   if(ext == 'jpe') {
     ext = 'jpg';

lib/utils/import_comic.dart

@@ -20,7 +20,7 @@ class ImportComic {
   const ImportComic({this.selectedFolder, this.copyToLocal = true});
 
   Future<bool> cbz() async {
-    var file = await selectFile(ext: ['cbz', 'zip']);
+    var file = await selectFile(ext: ['cbz', 'zip', '7z', 'cb7']);
     Map<String?, List<LocalComic>> imported = {};
     if (file == null) {
       return false;
@@ -42,7 +42,8 @@ class ImportComic {
     var dir = await picker.pickDirectory(directAccess: true);
     if (dir != null) {
       var files = (await dir.list().toList()).whereType<File>().toList();
-      files.removeWhere((e) => e.extension != 'cbz' && e.extension != 'zip');
+      const supportedExtensions = ['cbz', 'zip', '7z', 'cb7'];
+      files.removeWhere((e) => !supportedExtensions.contains(e.extension));
       Map<String?, List<LocalComic>> imported = {};
       var controller = showLoadingDialog(App.rootContext, allowCancel: false);
       var comics = <LocalComic>[];