import 'dart:convert';

import 'package:enter_farma_plus_mobile/src/core/storage/tenant_session_store.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

final offlinePosStoreProvider = Provider(
  (ref) => OfflinePosStore(ref.watch(secureStorageProvider)),
);

class OfflinePosStore {
  const OfflinePosStore(this._storage);

  static const _itemsKey = 'offline.pos.items_sale';
  static const _customersKey = 'offline.pos.customers';
  static const _tablesKey = 'offline.pos.document_tables';
  static const _pendingSalesKey = 'offline.pos.pending_sales';

  final FlutterSecureStorage _storage;

  Future<void> saveItems(List<Map<String, dynamic>> rows) async {
    await _storage.write(key: _itemsKey, value: jsonEncode(rows));
  }

  Future<void> saveCustomers(List<Map<String, dynamic>> rows) async {
    await _storage.write(key: _customersKey, value: jsonEncode(rows));
  }

  Future<void> saveTables(Map<String, dynamic> tables) async {
    await _storage.write(key: _tablesKey, value: jsonEncode(tables));
  }

  Future<List<Map<String, dynamic>>> readItems() async {
    return _readList(_itemsKey);
  }

  Future<List<Map<String, dynamic>>> readCustomers() async {
    return _readList(_customersKey);
  }

  Future<Map<String, dynamic>> readTables() async {
    final raw = await _storage.read(key: _tablesKey);
    if (raw == null || raw.isEmpty) return const <String, dynamic>{};
    final decoded = jsonDecode(raw);
    if (decoded is Map<String, dynamic>) return decoded;
    return const <String, dynamic>{};
  }

  Future<List<Map<String, dynamic>>> readPendingSales() async {
    return _readList(_pendingSalesKey);
  }

  Future<void> enqueuePendingSale(Map<String, dynamic> row) async {
    final pending = await readPendingSales();
    pending.add(row);
    await _storage.write(key: _pendingSalesKey, value: jsonEncode(pending));
  }

  Future<void> replacePendingSales(List<Map<String, dynamic>> rows) async {
    await _storage.write(key: _pendingSalesKey, value: jsonEncode(rows));
  }

  Future<void> updatePendingSale(
    String idempotencyKey,
    Map<String, dynamic> replacement,
  ) async {
    final rows = await readPendingSales();
    final updated = rows.map((row) {
      if ('${row['idempotency_key']}' == idempotencyKey) {
        return replacement;
      }
      return row;
    }).toList();
    await replacePendingSales(updated);
  }

  Future<void> removePendingSale(String idempotencyKey) async {
    final rows = await readPendingSales();
    final filtered = rows
        .where((row) => '${row['idempotency_key']}' != idempotencyKey)
        .toList();
    await replacePendingSales(filtered);
  }

  Future<List<Map<String, dynamic>>> _readList(String key) async {
    final raw = await _storage.read(key: key);
    if (raw == null || raw.isEmpty) return <Map<String, dynamic>>[];
    final decoded = jsonDecode(raw);
    if (decoded is! List) return <Map<String, dynamic>>[];

    return decoded
        .whereType<Map>()
        .map((e) => Map<String, dynamic>.from(e))
        .toList();
  }
}