/// Chat file tile
///
/// @author Pierre Hubert
import 'dart:io';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:comunic/helpers/conversation_files_helper.dart';
import 'package:comunic/models/conversation_message.dart';
import 'package:comunic/ui/widgets/async_screen_widget.dart';
import 'package:comunic/ui/widgets/audio_player_widget.dart';
import 'package:comunic/ui/widgets/network_image_widget.dart';
import 'package:comunic/utils/intl_utils.dart';
import 'package:comunic/utils/log_utils.dart';
import 'package:comunic/utils/ui_utils.dart';
import 'package:dio/dio.dart';
import 'package:filesize/filesize.dart';
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';

const _AreaSize = 150.0;

class ConversationFileWidget extends StatefulWidget {
  final int messageID;
  final ConversationMessageFile file;

  const ConversationFileWidget({
    Key key,
    @required this.messageID,
    @required this.file,
  })  : assert(messageID != null),
        assert(file != null),
        super(key: key);

  @override
  _ConversationFileWidgetState createState() => _ConversationFileWidgetState();
}

class _ConversationFileWidgetState extends State<ConversationFileWidget> {
  final _refreshKey = GlobalKey<AsyncScreenWidgetState>();

  File _targetFile;

  bool _isDownloaded;

  bool _downloading = false;
  var _downloadProgress = 0.0;
  CancelToken _cancelDownloadToken;

  ConversationMessageFile get file => widget.file;

  Future<void> _refresh() async {
    _targetFile = await ConversationFilesHelper.getPathForChatFile(
        widget.messageID, file);

    _isDownloaded = await _targetFile.exists();
  }

  @override
  Widget build(BuildContext context) {
    return Container(
      width: _AreaSize,
      height: _AreaSize,
      child: AsyncScreenWidget(
        key: _refreshKey,
        onReload: _refresh,
        onBuild: _buildContent,
        errorMessage: tr("Error!"),
      ),
    );
  }

  Widget _buildContent() => _isDownloaded || !file.downloadable
      ? _buildFileWidget()
      : _buildDownloadWidget();

  Widget _buildDownloadWidget() => Stack(
        children: <Widget>[
          // Thumbnail, if possible
          !file.hasThumbnail
              ? Container()
              : CachedNetworkImage(
                  imageUrl: file.thumbnail,
                  width: _AreaSize,
                  height: _AreaSize,
                  fit: BoxFit.fill,
                ),

          Container(
            width: _AreaSize,
            color: Color(0x66000000),
            child: DefaultTextStyle(
              style: TextStyle(color: Colors.white),
              child: Column(
                children: <Widget>[
                  Spacer(),
                  Icon(file.icon, color: Colors.white),
                  Spacer(),
                  _buildDownloadArea(),
                  Spacer(),
                  Text(filesize(file.size)),
                  Spacer(),
                ],
              ),
            ),
          )
        ],
      );

  Widget _buildDownloadArea() => _downloading
      ? _buildDownloadingWidget()
      : Material(
          borderRadius: BorderRadius.all(Radius.circular(2.0)),
          color: Colors.green,
          child: IconButton(
            icon: Icon(Icons.file_download),
            onPressed: _downloadFile,
            color: Colors.white,
          ),
        );

  Widget _buildDownloadingWidget() => Container(
        width: 36,
        height: 36,
        child: Stack(
          children: <Widget>[
            CircularProgressIndicator(value: _downloadProgress),
            Center(
              child: InkWell(
                onTap: () => _cancelDownloadToken.cancel(),
                child: Icon(Icons.cancel, color: Colors.white),
              ),
            )
          ],
        ),
      );

  Future<void> _downloadFile() async {
    try {
      setState(() {
        _cancelDownloadToken = CancelToken();
        _downloading = true;
        _downloadProgress = 0.0;
      });

      await ConversationFilesHelper.download(
        msgID: widget.messageID,
        fileInfo: file,
        onProgress: (p) => setState(() => _downloadProgress = p),
        cancelToken: _cancelDownloadToken,
      );

      await _refreshKey.currentState.refresh();
    } catch (e, s) {
      logError(e, s);
      showSimpleSnack(context, tr("Failed to download file!"));
    }

    setState(() {
      _downloading = false;
    });
  }

  Widget _buildFileWidget() {
    switch (file.fileType) {
      // Images
      case ConversationMessageFileType.IMAGE:
        return Center(
          child: NetworkImageWidget(
            url: file.url,
            thumbnailURL: file.thumbnail,
            allowFullScreen: true,
          ),
        );

      // Audio player
      case ConversationMessageFileType.AUDIO:
        return AudioPlayerWidget(_targetFile);

      // The file is not downloadable, we open it in the browser
      default:
        return Center(
          child: MaterialButton(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.center,
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Spacer(flex: 2),
                Icon(file.icon, color: Colors.white),
                Spacer(),
                Text(file.name, textAlign: TextAlign.center),
                Spacer(flex: 2),
              ],
            ),
            onPressed: () => launch(file.url),
          ),
        );
        break;
    }
  }
}