refactor: Split chat view into multiple files

lib/pages/chat/reactions_picker.dart

@@ -0,0 +1,75 @@
+import 'package:flutter/material.dart';
+
+import 'package:matrix/matrix.dart';
+
+import 'package:fluffychat/config/app_emojis.dart';
+import 'package:fluffychat/pages/chat/chat.dart';
+
+class ReactionsPicker extends StatelessWidget {
+  final ChatController controller;
+  const ReactionsPicker(this.controller, {Key key}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    if (controller.showEmojiPicker) return Container();
+    return AnimatedContainer(
+      duration: const Duration(milliseconds: 300),
+      height: (controller.editEvent == null &&
+              controller.replyEvent == null &&
+              controller.room.canSendDefaultMessages &&
+              controller.selectedEvents.length == 1)
+          ? 56
+          : 0,
+      child: Material(
+        color: Theme.of(context).secondaryHeaderColor,
+        child: Builder(builder: (context) {
+          if (!(controller.editEvent == null &&
+              controller.replyEvent == null &&
+              controller.selectedEvents.length == 1)) {
+            return Container();
+          }
+          final emojis = List<String>.from(AppEmojis.emojis);
+          final allReactionEvents = controller.selectedEvents.first
+              .aggregatedEvents(controller.timeline, RelationshipTypes.reaction)
+              ?.where((event) =>
+                  event.senderId == event.room.client.userID &&
+                  event.type == 'm.reaction');
+
+          for (final event in allReactionEvents) {
+            try {
+              emojis.remove(event.content['m.relates_to']['key']);
+            } catch (_) {}
+          }
+          return ListView.builder(
+            scrollDirection: Axis.horizontal,
+            itemCount: emojis.length + 1,
+            itemBuilder: (c, i) => i == emojis.length
+                ? InkWell(
+                    borderRadius: BorderRadius.circular(8),
+                    onTap: () => controller.pickEmojiAction(allReactionEvents),
+                    child: Container(
+                      width: 56,
+                      height: 56,
+                      alignment: Alignment.center,
+                      child: const Icon(Icons.add_outlined),
+                    ),
+                  )
+                : InkWell(
+                    borderRadius: BorderRadius.circular(8),
+                    onTap: () => controller.sendEmojiAction(emojis[i]),
+                    child: Container(
+                      width: 56,
+                      height: 56,
+                      alignment: Alignment.center,
+                      child: Text(
+                        emojis[i],
+                        style: const TextStyle(fontSize: 30),
+                      ),
+                    ),
+                  ),
+          );
+        }),
+      ),
+    );
+  }
+}