import 'package:flutter/material.dart';

import 'package:desktop_drop/desktop_drop.dart';
import 'package:flutter_gen/gen_l10n/l10n.dart';
import 'package:future_loading_dialog/future_loading_dialog.dart';
import 'package:matrix/matrix.dart';
import 'package:scroll_to_index/scroll_to_index.dart';
import 'package:swipe_to_action/swipe_to_action.dart';
import 'package:vrouter/vrouter.dart';

import 'package:fluffychat/config/app_config.dart';
import 'package:fluffychat/config/themes.dart';
import 'package:fluffychat/pages/chat/chat.dart';
import 'package:fluffychat/pages/chat/chat_app_bar_title.dart';
import 'package:fluffychat/pages/chat/encryption_button.dart';
import 'package:fluffychat/pages/chat/pinned_events.dart';
import 'package:fluffychat/pages/chat/reactions_picker.dart';
import 'package:fluffychat/pages/chat/reply_display.dart';
import 'package:fluffychat/pages/chat/seen_by_row.dart';
import 'package:fluffychat/pages/chat/tombstone_display.dart';
import 'package:fluffychat/pages/chat/typing_indicators.dart';
import 'package:fluffychat/pages/user_bottom_sheet/user_bottom_sheet.dart';
import 'package:fluffychat/utils/platform_infos.dart';
import 'package:fluffychat/utils/sentry_controller.dart';
import 'package:fluffychat/widgets/chat_settings_popup_menu.dart';
import 'package:fluffychat/widgets/connection_status_header.dart';
import 'package:fluffychat/widgets/matrix.dart';
import 'package:fluffychat/widgets/unread_badge_back_button.dart';
import '../../utils/stream_extension.dart';
import 'chat_emoji_picker.dart';
import 'chat_input_row.dart';
import 'events/message.dart';

enum _EventContextAction { info, report }

class ChatView extends StatelessWidget {
  final ChatController controller;

  const ChatView(this.controller, {Key? key}) : super(key: key);

  List<Widget> _appBarActions(BuildContext context) {
    if (controller.selectMode) {
      return [
        if (controller.canEditSelectedEvents)
          IconButton(
            icon: const Icon(Icons.edit_outlined),
            tooltip: L10n.of(context)!.edit,
            onPressed: controller.editSelectedEventAction,
          ),
        IconButton(
          icon: const Icon(Icons.copy_outlined),
          tooltip: L10n.of(context)!.copy,
          onPressed: controller.copyEventsAction,
        ),
        if (controller.canSaveSelectedEvent)
          IconButton(
            icon: Icon(Icons.adaptive.share),
            tooltip: L10n.of(context)!.share,
            onPressed: controller.saveSelectedEvent,
          ),
        if (controller.canRedactSelectedEvents)
          IconButton(
            icon: const Icon(Icons.delete_outlined),
            tooltip: L10n.of(context)!.redactMessage,
            onPressed: controller.redactEventsAction,
          ),
        IconButton(
          icon: const Icon(Icons.push_pin_outlined),
          onPressed: controller.pinEvent,
          tooltip: L10n.of(context)!.pinMessage,
        ),
        if (controller.selectedEvents.length == 1)
          PopupMenuButton<_EventContextAction>(
            onSelected: (action) {
              switch (action) {
                case _EventContextAction.info:
                  controller.showEventInfo();
                  controller.clearSelectedEvents();
                  break;
                case _EventContextAction.report:
                  controller.reportEventAction();
                  break;
              }
            },
            itemBuilder: (context) => [
              PopupMenuItem(
                value: _EventContextAction.info,
                child: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    const Icon(Icons.info_outlined),
                    const SizedBox(width: 12),
                    Text(L10n.of(context)!.messageInfo),
                  ],
                ),
              ),
              PopupMenuItem(
                value: _EventContextAction.report,
                child: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    const Icon(
                      Icons.shield_outlined,
                      color: Colors.red,
                    ),
                    const SizedBox(width: 12),
                    Text(L10n.of(context)!.reportMessage),
                  ],
                ),
              ),
            ],
          ),
      ];
    } else {
      return [
        if (Matrix.of(context).voipPlugin != null &&
            controller.room!.isDirectChat)
          IconButton(
            onPressed: controller.onPhoneButtonTap,
            icon: const Icon(Icons.call_outlined),
            tooltip: L10n.of(context)!.placeCall,
          ),
        EncryptionButton(controller.room!),
        ChatSettingsPopupMenu(controller.room!, !controller.room!.isDirectChat),
      ];
    }
  }

  @override
  Widget build(BuildContext context) {
    controller.matrix ??= Matrix.of(context);
    final client = controller.matrix!.client;
    controller.sendingClient ??= client;
    controller.room = controller.sendingClient!.getRoomById(controller.roomId!);
    if (controller.room == null) {
      return Scaffold(
        appBar: AppBar(
          title: Text(L10n.of(context)!.oopsSomethingWentWrong),
        ),
        body: Center(
          child: Text(L10n.of(context)!.youAreNoLongerParticipatingInThisChat),
        ),
      );
    }

    if (controller.room!.membership == Membership.invite) {
      showFutureLoadingDialog(
          context: context, future: () => controller.room!.join());
    }
    final bottomSheetPadding = FluffyThemes.isColumnMode(context) ? 16.0 : 8.0;
    final horizontalPadding = FluffyThemes.isColumnMode(context) ? 8.0 : 0.0;

    return VWidgetGuard(
      onSystemPop: (redirector) async {
        if (controller.selectedEvents.isNotEmpty) {
          controller.clearSelectedEvents();
          redirector.stopRedirection();
        } else if (controller.showEmojiPicker) {
          controller.emojiPickerAction();
          redirector.stopRedirection();
        }
      },
      child: GestureDetector(
        onTapDown: controller.setReadMarker,
        behavior: HitTestBehavior.opaque,
        child: StreamBuilder(
          stream: controller.room!.onUpdate.stream
              .rateLimit(const Duration(milliseconds: 250)),
          builder: (context, snapshot) => FutureBuilder<bool>(
            future: controller.getTimeline(),
            builder: (BuildContext context, snapshot) {
              return Scaffold(
                appBar: AppBar(
                  actionsIconTheme: IconThemeData(
                    color: controller.selectedEvents.isEmpty
                        ? null
                        : Theme.of(context).colorScheme.primary,
                  ),
                  leading: controller.selectMode
                      ? IconButton(
                          icon: const Icon(Icons.close),
                          onPressed: controller.clearSelectedEvents,
                          tooltip: L10n.of(context)!.close,
                          color: Theme.of(context).colorScheme.primary,
                        )
                      : UnreadBadgeBackButton(roomId: controller.roomId!),
                  titleSpacing: 0,
                  title: ChatAppBarTitle(controller),
                  actions: _appBarActions(context),
                ),
                floatingActionButton: controller.showScrollDownButton &&
                        controller.selectedEvents.isEmpty
                    ? Padding(
                        padding: const EdgeInsets.only(bottom: 56.0),
                        child: FloatingActionButton(
                          onPressed: controller.scrollDown,
                          mini: true,
                          child: const Icon(Icons.arrow_downward_outlined),
                        ),
                      )
                    : null,
                backgroundColor: Theme.of(context).colorScheme.surface,
                body: DropTarget(
                  onDragDone: controller.onDragDone,
                  onDragEntered: controller.onDragEntered,
                  onDragExited: controller.onDragExited,
                  child: Stack(
                    children: <Widget>[
                      if (Matrix.of(context).wallpaper != null)
                        Image.file(
                          Matrix.of(context).wallpaper!,
                          width: double.infinity,
                          height: double.infinity,
                          fit: BoxFit.cover,
                        ),
                      SafeArea(
                        child: Column(
                          children: <Widget>[
                            TombstoneDisplay(controller),
                            PinnedEvents(controller),
                            Expanded(
                              child: GestureDetector(
                                  onTap: controller.clearSingleSelectedEvent,
                                  child: Builder(
                                    builder: (context) {
                                      if (snapshot.hasError) {
                                        SentryController.captureException(
                                          snapshot.error,
                                          StackTrace.current,
                                        );
                                      }
                                      if (controller.timeline == null) {
                                        return const Center(
                                          child: CircularProgressIndicator
                                              .adaptive(strokeWidth: 2),
                                        );
                                      }

                                      // create a map of eventId --> index to greatly improve performance of
                                      // ListView's findChildIndexCallback
                                      final thisEventsKeyMap = <String, int>{};
                                      for (var i = 0;
                                          i < controller.filteredEvents.length;
                                          i++) {
                                        thisEventsKeyMap[controller
                                            .filteredEvents[i].eventId] = i;
                                      }
                                      return ListView.custom(
                                        padding: EdgeInsets.only(
                                          top: 16,
                                          bottom: 4,
                                          left: horizontalPadding,
                                          right: horizontalPadding,
                                        ),
                                        reverse: true,
                                        controller: controller.scrollController,
                                        keyboardDismissBehavior: PlatformInfos
                                                .isIOS
                                            ? ScrollViewKeyboardDismissBehavior
                                                .onDrag
                                            : ScrollViewKeyboardDismissBehavior
                                                .manual,
                                        childrenDelegate:
                                            SliverChildBuilderDelegate(
                                          (BuildContext context, int i) {
                                            return i ==
                                                    controller.filteredEvents
                                                            .length +
                                                        1
                                                ? controller.timeline!
                                                        .isRequestingHistory
                                                    ? const Center(
                                                        child:
                                                            CircularProgressIndicator
                                                                .adaptive(
                                                                    strokeWidth:
                                                                        2),
                                                      )
                                                    : controller.canLoadMore
                                                        ? Center(
                                                            child:
                                                                OutlinedButton(
                                                              style:
                                                                  OutlinedButton
                                                                      .styleFrom(
                                                                backgroundColor:
                                                                    Theme.of(
                                                                            context)
                                                                        .scaffoldBackgroundColor,
                                                              ),
                                                              onPressed: controller
                                                                  .requestHistory,
                                                              child: Text(L10n.of(
                                                                      context)!
                                                                  .loadMore),
                                                            ),
                                                          )
                                                        : Container()
                                                : i == 0
                                                    ? Column(
                                                        mainAxisSize:
                                                            MainAxisSize.min,
                                                        children: [
                                                          SeenByRow(controller),
                                                          TypingIndicators(
                                                              controller),
                                                        ],
                                                      )
                                                    : AutoScrollTag(
                                                        key: ValueKey(controller
                                                            .filteredEvents[
                                                                i - 1]
                                                            .eventId),
                                                        index: i - 1,
                                                        controller: controller
                                                            .scrollController,
                                                        child: Swipeable(
                                                          key: ValueKey(controller
                                                              .filteredEvents[
                                                                  i - 1]
                                                              .eventId),
                                                          background:
                                                              const Padding(
                                                            padding: EdgeInsets
                                                                .symmetric(
                                                                    horizontal:
                                                                        12.0),
                                                            child: Center(
                                                              child: Icon(Icons
                                                                  .reply_outlined),
                                                            ),
                                                          ),
                                                          direction:
                                                              SwipeDirection
                                                                  .endToStart,
                                                          onSwipe: (direction) =>
                                                              controller.replyAction(
                                                                  replyTo: controller
                                                                          .filteredEvents[
                                                                      i - 1]),
                                                          child: Message(
                                                              controller.filteredEvents[
                                                                  i - 1],
                                                              onInfoTab: controller
                                                                  .showEventInfo,
                                                              onAvatarTab: (Event event) =>
                                                                  showModalBottomSheet(
                                                                    context:
                                                                        context,
                                                                    builder: (c) =>
                                                                        UserBottomSheet(
                                                                      user: event
                                                                          .sender,
                                                                      outerContext:
                                                                          context,
                                                                      onMention: () => controller
                                                                          .sendController
                                                                          .text += '${event.sender.mention} ',
                                                                    ),
                                                                  ),
                                                              unfold: controller
                                                                  .unfold,
                                                              onSelect: controller
                                                                  .onSelectMessage,
                                                              scrollToEventId:
                                                                  (String eventId) =>
                                                                      controller.scrollToEventId(
                                                                          eventId),
                                                              longPressSelect:
                                                                  controller
                                                                      .selectedEvents
                                                                      .isEmpty,
                                                              selected: controller
                                                                  .selectedEvents
                                                                  .any((e) => e.eventId == controller.filteredEvents[i - 1].eventId),
                                                              timeline: controller.timeline!,
                                                              nextEvent: i < controller.filteredEvents.length ? controller.filteredEvents[i] : null),
                                                        ),
                                                      );
                                          },
                                          childCount:
                                              controller.filteredEvents.length +
                                                  2,
                                          findChildIndexCallback: (key) =>
                                              controller.findChildIndexCallback(
                                                  key, thisEventsKeyMap),
                                        ),
                                      );
                                    },
                                  )),
                            ),
                            if (controller.room!.canSendDefaultMessages &&
                                controller.room!.membership == Membership.join)
                              Container(
                                margin: EdgeInsets.only(
                                  bottom: bottomSheetPadding,
                                  left: bottomSheetPadding,
                                  right: bottomSheetPadding,
                                ),
                                constraints: const BoxConstraints(
                                    maxWidth: FluffyThemes.columnWidth * 2.5),
                                alignment: Alignment.center,
                                child: Material(
                                  borderRadius: const BorderRadius.only(
                                    bottomLeft:
                                        Radius.circular(AppConfig.borderRadius),
                                    bottomRight:
                                        Radius.circular(AppConfig.borderRadius),
                                  ),
                                  elevation: 6,
                                  shadowColor: Theme.of(context)
                                      .secondaryHeaderColor
                                      .withAlpha(100),
                                  clipBehavior: Clip.hardEdge,
                                  color: Theme.of(context)
                                      .appBarTheme
                                      .backgroundColor,
                                  child: Column(
                                    mainAxisSize: MainAxisSize.min,
                                    children: [
                                      const ConnectionStatusHeader(),
                                      ReactionsPicker(controller),
                                      ReplyDisplay(controller),
                                      ChatInputRow(controller),
                                      ChatEmojiPicker(controller),
                                    ],
                                  ),
                                ),
                              ),
                          ],
                        ),
                      ),
                      if (controller.dragging)
                        Container(
                          color: Theme.of(context)
                              .scaffoldBackgroundColor
                              .withOpacity(0.9),
                          alignment: Alignment.center,
                          child: const Icon(
                            Icons.upload_outlined,
                            size: 100,
                          ),
                        ),
                    ],
                  ),
                ),
              );
            },
          ),
        ),
      ),
    );
  }
}