import 'dart:convert';
import 'dart:typed_data';

import 'package:http/http.dart' as http;
import 'package:http_parser/http_parser.dart';
import 'package:uuid/uuid.dart';

import '../app_config.dart';
import '../session/session.dart';

class ApiException implements Exception {
  ApiException(this.message);
  final String message;
  @override
  String toString() => message;
}

class OaClient {
  OaClient(this.session);
  final SessionStore session;
  bool _refreshing = false;

  Uri _uri(String path, [Map<String, String>? query]) {
    final base = session.apiBase.replaceAll(RegExp(r'/$'), '');
    final p = path.startsWith('/') ? path : '/$path';
    return Uri.parse('$base$p').replace(queryParameters: query);
  }

  Map<String, String> _headers({bool auth = true}) {
    final h = <String, String>{
      'Content-Type': 'application/json',
      'X-Request-Id': const Uuid().v4(),
    };
    if (auth && session.accessToken.isNotEmpty) {
      h['Authorization'] = 'Bearer ${session.accessToken}';
    }
    return h;
  }

  Future<dynamic> get(String path, {Map<String, String>? query}) =>
      _send('GET', path, query: query);

  Future<dynamic> post(String path, [Map<String, dynamic>? body]) =>
      _send('POST', path, body: body);

  Future<dynamic> patch(String path, [Map<String, dynamic>? body]) =>
      _send('PATCH', path, body: body);

  final _fileCache = <String, Uint8List>{};

  Uint8List? peekFile(String id) => _fileCache[id];

  Future<Uint8List?> fileBytes(String id) async {
    if (id.isEmpty) return null;
    final hit = _fileCache[id];
    if (hit != null) return hit;
    final uri = _uri('/files/$id');
    final headers = <String, String>{
      'X-Request-Id': const Uuid().v4(),
      if (session.accessToken.isNotEmpty) 'Authorization': 'Bearer ${session.accessToken}',
    };
    try {
      var res = await http.get(uri, headers: headers).timeout(const Duration(seconds: 30));
      if (res.statusCode == 401 && session.refreshToken.isNotEmpty) {
        final ok = await _refresh();
        if (ok) {
          headers['Authorization'] = 'Bearer ${session.accessToken}';
          res = await http.get(uri, headers: headers).timeout(const Duration(seconds: 30));
        }
      }
      if (res.statusCode >= 400 || res.bodyBytes.isEmpty) return null;
      if (_fileCache.length > 80) _fileCache.remove(_fileCache.keys.first);
      _fileCache[id] = res.bodyBytes;
      return res.bodyBytes;
    } catch (_) {
      return null;
    }
  }

  Future<Uint8List?> getBytes(String path, {Map<String, String>? query}) async {
    final uri = _uri(path, query);
    final headers = <String, String>{
      'X-Request-Id': const Uuid().v4(),
      if (session.accessToken.isNotEmpty) 'Authorization': 'Bearer ${session.accessToken}',
    };
    try {
      var res = await http.get(uri, headers: headers).timeout(const Duration(seconds: 20));
      if (res.statusCode == 401 && session.refreshToken.isNotEmpty) {
        final ok = await _refresh();
        if (ok) {
          headers['Authorization'] = 'Bearer ${session.accessToken}';
          res = await http.get(uri, headers: headers).timeout(const Duration(seconds: 20));
        }
      }
      if (res.statusCode >= 400 || res.bodyBytes.isEmpty) return null;
      return res.bodyBytes;
    } catch (_) {
      return null;
    }
  }

  Future<Map<String, dynamic>> uploadFile({
    required String filePath,
    required String filename,
    required String bizType,
    required String bizId,
    String? mime,
  }) async {
    final uri = _uri('/files');
    final type = _mediaType(filename, mime);
    Future<http.Response> send() async {
      final req = http.MultipartRequest('POST', uri);
      req.headers['Authorization'] = 'Bearer ${session.accessToken}';
      req.headers['X-Request-Id'] = const Uuid().v4();
      req.fields['bizType'] = bizType;
      req.fields['bizId'] = bizId;
      req.files.add(await http.MultipartFile.fromPath('file', filePath, filename: filename, contentType: type));
      return http.Response.fromStream(await req.send().timeout(const Duration(seconds: 60)));
    }

    var res = await send();
    if (res.statusCode == 401 && session.refreshToken.isNotEmpty) {
      final ok = await _refresh();
      if (ok) res = await send();
    }
    if ((res.statusCode == 502 || res.statusCode == 503) && session.accessToken.isNotEmpty) {
      await Future<void>.delayed(const Duration(milliseconds: 700));
      res = await send();
    }
    dynamic json;
    try {
      json = res.body.isEmpty ? null : jsonDecode(res.body);
    } catch (_) {
      throw ApiException(res.statusCode >= 400 ? '上传失败 ${res.statusCode}' : '响应无法解析');
    }
    if (json is Map && json['code'] != null && json['code'] != 0) {
      throw ApiException('${json['message'] ?? '上传失败'}');
    }
    if (res.statusCode >= 400) {
      final msg = json is Map ? (json['message'] ?? json['error'] ?? res.statusCode) : res.statusCode;
      throw ApiException('$msg');
    }
    final data = json is Map && json.containsKey('data') ? json['data'] : json;
    return data is Map ? Map<String, dynamic>.from(data) : {'id': '$data'};
  }

  Future<dynamic> _send(
    String method,
    String path, {
    Map<String, String>? query,
    Map<String, dynamic>? body,
    bool retry = true,
  }) async {
    final uri = _uri(path, query);
    final headers = _headers(
      auth: !path.startsWith('/auth/login') &&
          !path.startsWith('/auth/sms-code') &&
          path != '/auth/login-options' &&
          path != '/system/app-release' &&
          !path.startsWith('/legal'),
    );
    http.Response res;
    try {
      if (method == 'GET') {
        res = await http.get(uri, headers: headers).timeout(const Duration(seconds: 30));
      } else if (method == 'PATCH') {
        res = await http.patch(uri, headers: headers, body: jsonEncode(body ?? {})).timeout(const Duration(seconds: 30));
      } else {
        res = await http.post(uri, headers: headers, body: jsonEncode(body ?? {})).timeout(const Duration(seconds: 30));
      }
    } catch (e) {
      throw ApiException('网络不可用：$e');
    }
    if ((res.statusCode == 502 || res.statusCode == 503) && retry) {
      await Future<void>.delayed(const Duration(milliseconds: 700));
      return _send(method, path, query: query, body: body, retry: false);
    }
    if (res.statusCode == 401 && retry && session.refreshToken.isNotEmpty && !path.contains('/auth/refresh')) {
      final ok = await _refresh();
      if (ok) return _send(method, path, query: query, body: body, retry: false);
      await session.clear();
      throw ApiException('登录已过期，请重新登录');
    }
    dynamic json;
    try {
      json = res.body.isEmpty ? null : jsonDecode(res.body);
    } catch (_) {
      throw ApiException(res.statusCode >= 400 ? '请求失败 ${res.statusCode}' : '响应无法解析');
    }
    if (json is Map && json['code'] != null && json['code'] != 0) {
      throw ApiException('${json['message'] ?? '请求失败'}');
    }
    if (res.statusCode >= 400) {
      final msg = json is Map ? (json['message'] ?? json['error'] ?? res.statusCode) : res.statusCode;
      throw ApiException('$msg');
    }
    if (json is Map && json.containsKey('data')) return json['data'];
    return json;
  }

  Future<bool> _refresh() async {
    if (_refreshing) return false;
    _refreshing = true;
    try {
      final uri = _uri('/auth/refresh');
      final res = await http.post(
        uri,
        headers: _headers(auth: false),
        body: jsonEncode({
          'refreshToken': session.refreshToken,
          'clientKind': 'mobile',
        }),
      );
      if (res.statusCode >= 400) return false;
      final json = jsonDecode(res.body);
      final data = json is Map && json['data'] is Map ? json['data'] as Map : json;
      final access = '${data['accessToken'] ?? ''}';
      final refresh = '${data['refreshToken'] ?? ''}';
      if (access.isEmpty) return false;
      await session.setTokens(access, refresh.isEmpty ? session.refreshToken : refresh);
      return true;
    } catch (_) {
      return false;
    } finally {
      _refreshing = false;
    }
  }

  MediaType _mediaType(String filename, String? mime) {
    var raw = (mime ?? '').split(';').first.trim().toLowerCase();
    if (raw == 'image/jpg' || raw == 'image/pjpeg') raw = 'image/jpeg';
    if (raw.isEmpty || raw == 'application/octet-stream') {
      final n = filename.toLowerCase();
      if (n.endsWith('.jpg') || n.endsWith('.jpeg')) {
        raw = 'image/jpeg';
      } else if (n.endsWith('.png')) {
        raw = 'image/png';
      } else if (n.endsWith('.gif')) {
        raw = 'image/gif';
      } else if (n.endsWith('.webp')) {
        raw = 'image/webp';
      } else if (n.endsWith('.m4a') || n.endsWith('.mp4')) {
        raw = 'audio/mp4';
      } else if (n.endsWith('.pdf')) {
        raw = 'application/pdf';
      } else {
        raw = 'application/octet-stream';
      }
    }
    try {
      return MediaType.parse(raw);
    } catch (_) {
      return MediaType('application', 'octet-stream');
    }
  }
}

List<Map<String, dynamic>> asMaps(dynamic data) {
  final list = extractList(data);
  return list.whereType<Map>().map((e) => Map<String, dynamic>.from(e)).toList();
}

List<dynamic> extractList(dynamic data) {
  if (data is List) return data;
  if (data is Map) {
    for (final k in ['items', 'list', 'rows', 'records', 'data']) {
      if (data[k] is List) return data[k] as List;
    }
  }
  return const [];
}

String scalarText(dynamic v) {
  if (v == null) return '';
  if (v is Map) {
    return '${v['displayName'] ?? v['name'] ?? v['title'] ?? v['departmentName'] ?? ''}'.trim();
  }
  if (v is List) {
    return v.map(scalarText).where((e) => e.isNotEmpty).join('、');
  }
  final s = '$v'.trim();
  if (s.startsWith('{') && (s.contains('id:') || s.contains('tenantId'))) return '';
  return s;
}

String pickTitle(Map<String, dynamic> row) {
  for (final k in [
    'title',
    'name',
    'displayName',
    'projectName',
    'bidNo',
    'contractNo',
    'claimNo',
    'loanNo',
    'projectNo',
    'purpose',
    'reason',
    'label',
  ]) {
    final s = scalarText(row[k]);
    if (s.isNotEmpty) return s;
  }
  return row['id']?.toString() ?? '未命名';
}

String pickSub(Map<String, dynamic> row) {
  for (final k in [
    'departmentName',
    'department',
    'status',
    'title',
    'bidNo',
    'contractNo',
    'claimNo',
    'kind',
    'mobile',
    'lastText',
    'employmentStatus',
  ]) {
    final s = scalarText(row[k]);
    if (s.isNotEmpty) return s;
  }
  return '';
}

String fmtTime(dynamic v) {
  if (v == null) return '';
  final s = '$v';
  final t = DateTime.tryParse(s);
  if (t != null) {
    final local = t.toLocal();
    final date = '${local.year.toString().padLeft(4, '0')}-${local.month.toString().padLeft(2, '0')}-${local.day.toString().padLeft(2, '0')}';
    final time = '${local.hour.toString().padLeft(2, '0')}:${local.minute.toString().padLeft(2, '0')}:${local.second.toString().padLeft(2, '0')}';
    return '$date $time';
  }
  if (s.length >= 16) return s.substring(0, 16).replaceFirst('T', ' ');
  return s;
}

String shortTime(dynamic v) {
  if (v == null) return '';
  final t = DateTime.tryParse('$v');
  if (t == null) return fmtTime(v);
  final now = DateTime.now();
  final local = t.toLocal();
  final today = DateTime(now.year, now.month, now.day);
  final day = DateTime(local.year, local.month, local.day);
  final hh = local.hour.toString().padLeft(2, '0');
  final mm = local.minute.toString().padLeft(2, '0');
  if (day == today) return '$hh:$mm';
  if (day == today.subtract(const Duration(days: 1))) return '昨天';
  const week = ['一', '二', '三', '四', '五', '六', '日'];
  if (today.difference(day).inDays < 7) return '周${week[local.weekday - 1]}';
  return '${local.month}/${local.day}';
}

const defaultApiHint = AppConfig.defaultApiBase;