implemented the Ticker module with a native ProseMirror document renderer and integrated API support for structured content, navigation trees, and proxied files

2026-07-09 00:51:08 +02:00
parent 1114291313
commit cedeb06569
57 changed files with 4758 additions and 43 deletions
@@ -0,0 +1,124 @@
+import 'package:cached_network_image/cached_network_image.dart';
+import 'package:collection/collection.dart';
+import 'package:flutter/material.dart';
+
+import 'pm_document_view.dart';
+import 'pm_node.dart';
+
+/// Renders raw ProseMirror JSON and memoises the parsed tree across rebuilds.
+/// Parsing decodes base64 images; doing it in build() would re-decode them on
+/// every rebuild — call sites should use this instead of PmNode.fromJson.
+///
+/// Images are precached before a document is presented, so the reader never
+/// sees images pop in and text reflow downwards. Until the first document is
+/// ready a spinner shows; on updates the previous document stays visible until
+/// the new one is fully precached (no spinner flash on background refreshes).
+/// A timeout keeps a dead network image from blocking the swap forever (the
+/// image then renders with its broken-image fallback).
+class PmJsonView extends StatefulWidget {
+  final Map<String, dynamic> json;
+  final void Function(String href)? onLinkTap;
+
+  const PmJsonView({required this.json, this.onLinkTap, super.key});
+
+  static const Duration precacheTimeout = Duration(seconds: 8);
+
+  @override
+  State<PmJsonView> createState() => _PmJsonViewState();
+}
+
+class _PmJsonViewState extends State<PmJsonView> {
+  PmNode? _shown;
+  PmNode? _pending;
+  List<ImageProvider> _pendingProviders = const [];
+  bool _precacheStarted = false;
+  int _generation = 0;
+
+  @override
+  void initState() {
+    super.initState();
+    _parse();
+  }
+
+  @override
+  void didUpdateWidget(PmJsonView oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (identical(oldWidget.json, widget.json)) return;
+    // Background refreshes deliver a new map instance with identical content;
+    // re-parsing would re-decode every base64 image for a no-op swap.
+    if (const DeepCollectionEquality().equals(oldWidget.json, widget.json)) {
+      return;
+    }
+    _parse();
+    _precache();
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    _precache();
+  }
+
+  void _parse() {
+    final doc = PmNode.fromJson(widget.json);
+    final providers = <ImageProvider>[];
+    _collectProviders(doc, providers);
+    _generation++;
+    _precacheStarted = false;
+    if (providers.isEmpty) {
+      _shown = doc;
+      _pending = null;
+      _pendingProviders = const [];
+    } else {
+      _pending = doc;
+      _pendingProviders = providers;
+    }
+  }
+
+  void _precache() {
+    final pending = _pending;
+    if (pending == null || _precacheStarted) return;
+    _precacheStarted = true;
+    final generation = _generation;
+    Future.wait([
+          for (final provider in _pendingProviders)
+            precacheImage(provider, context, onError: (_, _) {}),
+        ])
+        .timeout(PmJsonView.precacheTimeout, onTimeout: () => const [])
+        .whenComplete(() {
+          if (mounted && generation == _generation) {
+            setState(() {
+              _shown = pending;
+              _pending = null;
+              _pendingProviders = const [];
+            });
+          }
+        });
+  }
+
+  void _collectProviders(PmNode node, List<ImageProvider> out) {
+    if (node is PmImage) {
+      final bytes = node.bytes;
+      if (bytes != null) {
+        out.add(MemoryImage(bytes));
+      } else if (node.src.startsWith('http')) {
+        out.add(CachedNetworkImageProvider(node.src));
+      }
+    }
+    for (final child in node.children) {
+      _collectProviders(child, out);
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final shown = _shown;
+    if (shown == null) {
+      return const SizedBox(
+        height: 160,
+        child: Center(child: CircularProgressIndicator()),
+      );
+    }
+    return PmDocumentView(doc: shown, onLinkTap: widget.onLinkTap);
+  }
+}