fis_lib_theme/lib/resource.dart

import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'dart:typed_data';

import 'package:fis_common/helpers/http.dart';
import 'package:fis_common/index.dart';
import 'package:fis_common/logger/logger.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:path_provider/path_provider.dart';

import 'consts.dart';
import 'manifest.dart';
import 'theme.dart';

/// 资源来源
enum FResourceFromType {
  local, // 本地
  network, // 网络
}

/// 资源配置信息实体
class FResourceInfo {
  final String key;
  final FResourceFromType from;
  final String path;

  const FResourceInfo({
    required this.key,
    required this.from,
    required this.path,
  });

  factory FResourceInfo.fromJson(Map<String, dynamic> json) {
    return FResourceInfo(
      key: json['key'],
      from: FResourceFromType.values[json['from']],
      path: json['path'],
    );
  }
}

/// 资源索引键
class FResourceKey {
  final String value;
  const FResourceKey(this.value);
}

/// Fis资源集
abstract class FResourceBundle {
  static AssetBundle? assetBundle;

  late String _resourcePath;

  /// 资源路径
  String get resourcePath => _resourcePath;

  /// 设置资源路径
  void setResourcePath(String value) => _resourcePath = value;

  final Map<String, Future<String>> _stringCache = <String, Future<String>>{};
  final Map<String, Future<dynamic>> _structuredDataCache =
      <String, Future<dynamic>>{};
  Map<String, FResourceInfo> _resourceMap = Map<String, FResourceInfo>();

  /// 主题清单内存映射
  late FThemeManifestInfo _manifestInfoRefer;

  @protected
  Future<ByteData> _innerLoad(FResourceInfo info);

  /// 加载资源数据
  Future<ByteData> load(FResourceKey key) async {
    FResourceInfo? resourceInfo = _getInfo(key.value);
    if (resourceInfo == null) return ByteData(0);
    if (resourceInfo.from == FResourceFromType.network) {
      return await _loadFromNetwork(resourceInfo);
    }
    ByteData data;
    if (FTheme.ins.defaultName == _manifestInfoRefer.name) {
      var path =
          "packages/${FisUIConsts.themePackageName}/assets/${resourceInfo.path}";
      data = await (FResourceBundle.assetBundle ?? rootBundle).load(path);
    } else {
      data = await _innerLoad(resourceInfo);
    }
    return data;
  }

  Future<ByteData> _loadFromNetwork(FResourceInfo resourceInfo) async {
    try {
      var bytes = await FHttpHelper.downloadBytes(resourceInfo.path);
      if (bytes != null) {
        return bytes.buffer.asByteData();
      }
    } catch (e) {
      logger.e("Load resource-${resourceInfo.key} from network error.", e);
    }
    return ByteData(0);
  }

  /// 获取字符串
  Future<String> loadString(FResourceKey key, {bool cache = true}) {
    if (cache)
      return _stringCache.putIfAbsent(key.value, () => _innerLoadString(key));
    return _innerLoadString(key);
  }

  /// 获取结构化数据
  Future<T> loadStructuredData<T>(
      FResourceKey key, Future<T> parser(String value)) {
    String keyString = key.value;
    if (_structuredDataCache.containsKey(keyString))
      return _structuredDataCache[keyString]! as Future<T>;
    Completer<T>? completer;
    Future<T>? result;
    loadString(key, cache: false).then<T>(parser).then<void>((T value) {
      result = SynchronousFuture<T>(value);
      _structuredDataCache[keyString] = result!;
      if (completer != null) {
        completer.complete(value);
      }
    });
    if (result != null) {
      return result!;
    }
    completer = Completer<T>();
    _structuredDataCache[keyString] = completer.future;
    return completer.future;
  }

  /// 获取字节数组
  Future<Uint8List> loadAsBytes(FResourceKey key) async {
    var byteData = await load(key);
    return byteData.buffer.asUint8List();
  }

  /// 载入资源map和初始化
  void init(FThemeManifestInfo manifestInfo) {
    try {
      _manifestInfoRefer = manifestInfo;
      _resourceMap = Map.fromIterable(manifestInfo.resources,
          key: (item) => (item as FResourceInfo).key, value: (item) => item);
      clearCache();
    } catch (e) {}
  }

  /// 收回指定缓存
  void evict(FResourceKey key) {
    _stringCache.remove(key.value);
    _structuredDataCache.remove(key.value);
  }

  /// 清除缓存
  void clearCache() {
    _stringCache.clear();
    _structuredDataCache.clear();
    print('FResourceBundle clear cache!');
  }

  Future<String> _innerLoadString(FResourceKey key, {bool cache = true}) async {
    final ByteData data = await load(key);
    if (data.lengthInBytes < 50 * 1024) {
      return utf8.decode(data.buffer.asUint8List());
    }
    return compute(_utf8decode, data, debugLabel: 'UTF8 decode for "$key"');
  }

  static String _utf8decode(ByteData data) {
    return utf8.decode(data.buffer.asUint8List());
  }

  @override
  String toString() => '${describeIdentity(this)}()';

  FResourceInfo? _getInfo(String key) {
    if (_resourceMap.containsKey(key)) {
      return _resourceMap[key];
    }
    return null;
  }
}

class _FResourceBundleNative extends FResourceBundle {
  Directory? _storageDirectory;

  @override
  Future<ByteData> _innerLoad(FResourceInfo info) async {
    try {
      final String storagePath = await _getStoragePath();
      final String themeName = super._manifestInfoRefer.name;
      final String filePath = "$storagePath/themes/$themeName/${info.path}";
      final Uint8List bytes = await File(filePath).readAsBytes();
      return bytes.buffer.asByteData();
    } catch (e) {
      logger.e("Load resource-${info.key} from file error.", e);
    }
    return ByteData(0);
  }

  Future<String> _getStoragePath() async {
    if (_storageDirectory == null) {
      _storageDirectory = await getApplicationDocumentsDirectory();
    }
    return _storageDirectory!.path;
  }
}

class _FResourceBundleWeb extends FResourceBundle {
  @override
  Future<ByteData> _innerLoad(FResourceInfo info) async {
    String url =
        "${_getUrlRoot()}/${super._manifestInfoRefer.name}/${info.path}";
    Uint8List? data = await FHttpHelper.downloadBytes(url);
    if (data != null) {
      return data.buffer.asByteData();
    }
    return ByteData(0);
  }

  @protected
  String _getUrlRoot() => resourcePath;
}

class _FResourceBundleShellWeb extends _FResourceBundleWeb {
  @override
  String _getUrlRoot() => "http://resource.fis.plus/themes";
}

FResourceBundle _createBundle() {
  switch (FPlatform.current) {
    case FPlatformEnum.android:
    case FPlatformEnum.iOS:
      return _FResourceBundleNative();
    case FPlatformEnum.web:
      return _FResourceBundleWeb();
    case FPlatformEnum.webOnWin:
    case FPlatformEnum.webOnMac:
      return _FResourceBundleShellWeb();
  }
}

final FResourceBundle fRootBundle = _createBundle();