// providers/license_purchase_provider.dart — 授权购买订单列表（订单管理 tab）。
// 后端 GET /license/purchases 只支持 page/page_size/status 三个查询轴；
// 套餐/关键词/下单时间筛选在列表屏做客户端过滤（当前页），与 stock_out 列表
// 屏「仓库」筛选同一established 口径（server 端无对应参数）。
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../core/auth/auth_state.dart';
import '../models/license.dart';
import 'license_provider.dart' show licenseRepositoryProvider;

final purchaseListProvider =
    AsyncNotifierProvider<PurchaseListNotifier, PurchaseListResult>(
  PurchaseListNotifier.new,
);

class PurchaseListNotifier extends AsyncNotifier<PurchaseListResult> {
  int _page = 1;
  int _pageSize = 10;
  String _status = ''; // '' | pending | paid | failed
  PurchaseListResult? _cache;

  @override
  Future<PurchaseListResult> build() async {
    ref.watch(authStateProvider.select((s) => s.user?.shopId));
    try {
      final result = await _fetch();
      _cache = result;
      return result;
    } catch (_) {
      if (_cache != null) return _cache!;
      rethrow;
    }
  }

  Future<PurchaseListResult> _fetch() {
    return ref.read(licenseRepositoryProvider).listPurchases(
          page: _page,
          pageSize: _pageSize,
          status: _status.isEmpty ? null : _status,
        );
  }

  int get page => _page;
  int get pageSize => _pageSize;
  String get currentStatus => _status;

  void reload() {
    // 保留上一次数据（isReloading）→ 屏幕可继续渲染旧内容 + 叠加半透明进度，不白屏。
    state = const AsyncValue<PurchaseListResult>.loading()
        .copyWithPrevious(state);
    _fetch().then((result) {
      _cache = result;
      state = AsyncValue.data(result);
    }, onError: (Object e, StackTrace st) {
      if (_cache != null) {
        state = AsyncValue.data(_cache!);
      } else {
        state = AsyncValue.error(e, st);
      }
    });
  }

  void setPage(int p) {
    _page = p;
    reload();
  }

  void setPageSize(int size) {
    _pageSize = size;
    _page = 1;
    reload();
  }

  void setStatus(String status) {
    _status = status;
    _page = 1;
    reload();
  }
}