import 'package:cached_network_image/cached_network_image.dart';
import 'package:comunic/helpers/conversations_helper.dart';
import 'package:comunic/helpers/server_config_helper.dart';
import 'package:comunic/helpers/users_helper.dart';
import 'package:comunic/lists/users_list.dart';
import 'package:comunic/models/conversation.dart';
import 'package:comunic/models/new_conversation.dart';
import 'package:comunic/models/new_conversation_settings.dart';
import 'package:comunic/models/user.dart';
import 'package:comunic/ui/dialogs/color_picker_dialog.dart';
import 'package:comunic/ui/dialogs/pick_file_dialog.dart';
import 'package:comunic/ui/routes/main_route/main_route.dart';
import 'package:comunic/ui/tiles/simple_user_tile.dart';
import 'package:comunic/ui/widgets/async_screen_widget.dart';
import 'package:comunic/ui/widgets/comunic_back_button_widget.dart';
import 'package:comunic/ui/widgets/pick_user_widget.dart';
import 'package:comunic/utils/account_utils.dart';
import 'package:comunic/utils/color_utils.dart';
import 'package:comunic/utils/dart_color.dart';
import 'package:comunic/utils/intl_utils.dart';
import 'package:comunic/utils/log_utils.dart';
import 'package:comunic/utils/ui_utils.dart';
import 'package:flutter/material.dart';

/// Create / Update conversation screen
///
/// @author Pierre HUBERT

enum _MembersMenuChoices { TOGGLE_ADMIN_STATUS, REMOVE }

class UpdateConversationScreen extends StatefulWidget {
  final convID;

  const UpdateConversationScreen({
    Key key,
    this.convID,
  }) : super(key: key);

  @override
  State<StatefulWidget> createState() => _UpdateConversationScreen();
}

class _UpdateConversationScreen extends State<UpdateConversationScreen> {
  Conversation _conversation;

  TextEditingController _nameController = TextEditingController();
  TextEditingController _colorController = TextEditingController();
  UsersList _members = UsersList();
  Set<int> _admins = Set();
  bool _followConversation = true;
  bool _canEveryoneAddMembers = true;
  String _image;

  String get _conversationColor => _colorController.text;

  Color get _color {
    if (_conversationColor == null || _conversationColor.isEmpty) return null;

    try {
      return HexColor(_conversationColor);
    } catch (e, s) {
      logError(e, s);
      return null;
    }
  }

  get isUpdating => widget.convID != null;

  get isAdmin => !isUpdating || _conversation.isAdmin;

  bool get _canAddMembers =>
      (isAdmin || _conversation.canEveryoneAddMembers) &&
      (!isUpdating || !_conversation.isManaged);

  get _isValid => _members.length > 0;

  Future<void> _init() async {
    if (!isUpdating) {
      _admins.add(userID());
      return;
    }

    _conversation =
        await ConversationsHelper().getSingle(widget.convID, force: true);

    _nameController.text = _conversation.name ?? "";
    _colorController.text = _conversation.color == null
        ? ""
        : "#${colorToHex(_conversation.color)}";
    _members = await UsersHelper().getList(_conversation.membersID);
    _admins = _conversation.adminsID;
    _followConversation = _conversation.following;
    _canEveryoneAddMembers = _conversation.canEveryoneAddMembers;
    _image = _conversation.logoURL;

    setState(() {});
  }

  @override
  Widget build(BuildContext context) => Scaffold(
        appBar: AppBar(
          leading: ComunicBackButton(),
          title: Text(isUpdating
              ? tr("Update conversation")
              : tr("Create a conversation")),
          actions: [
            IconButton(
                icon: Icon(Icons.check),
                onPressed: _isValid ? _submitForm : null)
          ],
        ),
        body: AsyncScreenWidget(
          onReload: _init,
          onBuild: _buildBody,
          errorMessage: tr("Failed to load conversation settings!"),
        ),
      );

  Widget _buildBody() {
    return SingleChildScrollView(
      child: Container(
        padding: EdgeInsets.all(8.0),
        child: Column(
          children: <Widget>[
            // Conversation name
            TextField(
              controller: _nameController,
              decoration: InputDecoration(
                labelText: tr("Conversation name (optional)"),
                alignLabelWithHint: true,
                enabled: isAdmin,
              ),
            ),

            // Conversation color
            TextField(
              controller: _colorController,
              onChanged: (s) => setState(() {}),
              decoration: InputDecoration(
                  labelText: tr("Conversation color (optional)"),
                  alignLabelWithHint: true,
                  enabled: isAdmin,
                  suffixIcon: IconButton(
                    icon: Icon(Icons.colorize),
                    color: _color,
                    onPressed: isAdmin ? _pickColor : null,
                  )),
            ),

            // Follow conversation ?
            Row(
              children: <Widget>[
                Switch.adaptive(
                  value: _followConversation,
                  onChanged: (b) => setState(() {
                    _followConversation = b;
                  }),
                ),
                Text(tr("Follow conversation"))
              ],
            ),

            // Allow every members of the conversation to add users ?
            Row(
              children: <Widget>[
                Switch.adaptive(
                  value: _canEveryoneAddMembers,
                  onChanged: isAdmin
                      ? (b) => setState(() {
                            _canEveryoneAddMembers = b;
                          })
                      : null,
                ),
                Text(tr("Allow all members of the conversation to add users"))
              ],
            ),

            // Add a member to the conversation
            PickUserWidget(
                resetOnChoose: true,
                keepFocusOnChoose: true,
                label: tr("Add member"),
                enabled: _canAddMembers,
                onSelectUser: (user) => _addMember(user)),

            //Conversation members
            Column(
              children: _members.map((f) => _buildMemberTile(f)).toList(),
            ),

            // Conversation image
            isUpdating ? _buildConversationImageWidget() : Container(),
          ],
        ),
      ),
    );
  }

  Widget _buildMemberTile(User user) => SimpleUserTile(
        user: user,
        subtitle: _admins.contains(user.id) ? tr("Admin") : tr("Member"),
        trailing: _canAddMembers
            ? PopupMenuButton<_MembersMenuChoices>(
                onSelected: (choice) => _membersMenuItemSelected(user, choice),
                itemBuilder: (c) => <PopupMenuEntry<_MembersMenuChoices>>[
                  PopupMenuItem(
                    child: Text(tr("Toggle admin status")),
                    value: _MembersMenuChoices.TOGGLE_ADMIN_STATUS,
                    enabled: isUpdating && isAdmin && user.id != userID(),
                  ),
                  PopupMenuItem(
                    child: Text(tr("Remove")),
                    value: _MembersMenuChoices.REMOVE,
                    enabled: isAdmin && user.id != userID(),
                  ),
                ],
              )
            : null,
      );

  void _pickColor() async {
    final color = await showColorPickerDialog(context, _color);
    setState(() =>
        _colorController.text = color == null ? "" : "#${colorToHex(color)}");
  }

  /// An option of the members menu has been selected
  void _membersMenuItemSelected(User user, _MembersMenuChoices choice) {
    if (choice == null) return;

    switch (choice) {
      case _MembersMenuChoices.REMOVE:
        _removeMember(user);
        break;

      case _MembersMenuChoices.TOGGLE_ADMIN_STATUS:
        _toggleAdminStatus(user);
        break;
    }
  }

  void _addMember(User user) async {
    try {
      if (_members.contains(user)) return;

      if (isUpdating)
        await ConversationsHelper.addMember(_conversation.id, user.id);

      setState(() => _members.insert(0, user));
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to add member to conversation!"));
    }
  }

  void _removeMember(User user) async {
    try {
      if (isUpdating)
        await ConversationsHelper.removeMember(_conversation.id, user.id);

      setState(() {
        _members.removeWhere((u) => u.id == user.id);
        _admins.remove(user.id);
      });
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to remove member!"));
    }
  }

  void _toggleAdminStatus(User user) async {
    try {
      final setAdmin = !_admins.contains(user.id);
      await ConversationsHelper.setAdmin(_conversation.id, user.id, setAdmin);

      setState(() {
        if (!setAdmin)
          _admins.remove(user.id);
        else
          _admins.add(user.id);
      });
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to toggle admin status of user!"));
    }
  }

  /// Submit the conversation
  Future<void> _submitForm() async {
    try {
      // Create the conversation
      if (!isUpdating) {
        final conversationID = await ConversationsHelper.createConversation(
            NewConversation(
                name: _nameController.text,
                members: _members.map((element) => element.id).toList(),
                follow: _followConversation,
                canEveryoneAddMembers: _canEveryoneAddMembers,
                color: _color));

        MainController.of(context).popPage();
        MainController.of(context).openConversation(conversationID);
        return;
      }

      // Update conversation settings
      final newSettings = NewConversationsSettings(
        convID: _conversation.id,
        following: _followConversation,
        isComplete: isAdmin,
        name: _nameController.text,
        canEveryoneAddMembers: _canEveryoneAddMembers,
        color: _color,
      );

      await ConversationsHelper.updateConversation(newSettings);

      MainController.of(context).popPage();
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to update conversation settings!"));
    }
  }

  /// Conversation image management
  Widget _buildConversationImageWidget() => Column(
        children: [
          SizedBox(height: 10),
          Text(tr("Conversation logo"),
              style: TextStyle(fontWeight: FontWeight.bold)),
          SizedBox(height: 5),
          _image == null
              ? Text("No logo defined yet.")
              : CachedNetworkImage(imageUrl: _image),
          SizedBox(height: 5),
          isAdmin
              ? Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    OutlinedButton(
                      onPressed: _uploadNewLogo,
                      child: Text(tr("Change logo")),
                    ),
                    SizedBox(width: 5),
                    _image == null
                        ? Container()
                        : ElevatedButton(
                            onPressed: _deleteLogo,
                            child: Text(tr("Delete logo")),
                            style: ButtonStyle(
                                backgroundColor:
                                    MaterialStateProperty.all(Colors.red)),
                          ),
                  ],
                )
              : Container(),
          SizedBox(height: 10),
        ],
      );

  /// Upload new conversation logo
  Future<void> _uploadNewLogo() async {
    try {
      final newLogo = await showPickFileDialog(
        context: context,
        allowedMimeTypes: ["image/png", "image/jpeg", "image/gif"],
        imageMaxWidth: srvConfig.conversationsPolicy.maxLogoWidth,
        imageMaxHeight: srvConfig.conversationsPolicy.maxLogoHeight,
      );

      if (newLogo == null) return;

      await ConversationsHelper.changeImage(_conversation.id, newLogo);

      final newConvSettings =
          await ConversationsHelper().getSingle(_conversation.id, force: true);
      setState(() => _image = newConvSettings.logoURL);
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to change conversation logo !"));
    }
  }

  /// Delete conversation logo
  Future<void> _deleteLogo() async {
    try {
      if (!await showConfirmDialog(
          context: context,
          message: tr("Do you really want to delete this logo?"))) return;

      await ConversationsHelper.removeLogo(_conversation.id);

      setState(() => _image = null);
    } catch (e, s) {
      logError(e, s);
      snack(context, tr("Failed to remove conversation logo!"));
    }
  }
}