feat: extract snippets into widgets, code cleanup document details

lib/features/paged_document_view/cubit/document_paging_bloc_mixin.dart

@@ -1,17 +1,15 @@
-import 'dart:developer';
-
 import 'package:collection/collection.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:paperless_api/paperless_api.dart';
 import 'package:paperless_mobile/core/notifier/document_changed_notifier.dart';
 
-import 'model/paged_documents_state.dart';
+import 'paged_documents_state.dart';
 
 ///
 /// Mixin which can be used on cubits that handle documents.
 /// This implements all paging and filtering logic.
 ///
-mixin PagedDocumentsMixin<State extends PagedDocumentsState>
+mixin DocumentPagingBlocMixin<State extends DocumentPagingState>
     on BlocBase<State> {
   PaperlessDocumentsApi get api;
   DocumentChangedNotifier get notifier;

lib/features/paged_document_view/cubit/paged_documents_state.dart

@@ -5,13 +5,13 @@ import 'package:paperless_api/paperless_api.dart';
 /// Base state for all blocs/cubits using a paged view of documents.
 /// [T] is the return type of the API call.
 ///
-abstract class PagedDocumentsState extends Equatable {
+abstract class DocumentPagingState extends Equatable {
   final bool hasLoaded;
   final bool isLoading;
   final List<PagedSearchResult<DocumentModel>> value;
   final DocumentFilter filter;
 
-  const PagedDocumentsState({
+  const DocumentPagingState({
     this.value = const [],
     this.hasLoaded = false,
     this.isLoading = false,

lib/features/paged_document_view/view/document_paging_view_mixin.dart

@@ -0,0 +1,43 @@
+import 'package:flutter/widgets.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:paperless_api/paperless_api.dart';
+import 'package:paperless_mobile/features/paged_document_view/cubit/document_paging_bloc_mixin.dart';
+import 'package:paperless_mobile/helpers/message_helpers.dart';
+import 'package:paperless_mobile/features/inbox/cubit/inbox_cubit.dart';
+
+mixin DocumentPagingViewMixin<T extends StatefulWidget> on State<T> {
+  ScrollController get pagingScrollController;
+
+  @override
+  void initState() {
+    super.initState();
+    pagingScrollController.addListener(shouldLoadMoreDocumentsListener);
+  }
+
+  @override
+  void dispose() {
+    pagingScrollController.removeListener(shouldLoadMoreDocumentsListener);
+    super.dispose();
+  }
+
+  DocumentPagingBlocMixin get _bloc => context.read<DocumentPagingBlocMixin>();
+
+  void shouldLoadMoreDocumentsListener() async {
+    if (shouldLoadMoreDocuments) {
+      try {
+        await _bloc.loadMore();
+      } on PaperlessServerException catch (error, stackTrace) {
+        showErrorMessage(context, error, stackTrace);
+      }
+    }
+  }
+
+  bool get shouldLoadMoreDocuments {
+    final currState = _bloc.state;
+    return pagingScrollController.position.maxScrollExtent != 0 &&
+        !currState.isLoading &&
+        !currState.isLastPageLoaded &&
+        pagingScrollController.offset >=
+            pagingScrollController.position.maxScrollExtent * 0.75;
+  }
+}