/// One shopping trip: receipt photo, supermarket, products and costs.
library;

import 'dart:io';

import 'package:flutter/material.dart';

import 'models/shop.dart';
import 'product_detail_screen.dart';
import 'services/product_repository.dart';
import 'utils/dates.dart';
import 'utils/money.dart';

class ShopDetailScreen extends StatefulWidget {
  const ShopDetailScreen({
    super.key,
    required this.repository,
    required this.shopId,
  });

  final ProductRepository repository;
  final int shopId;

  @override
  State<ShopDetailScreen> createState() => _ShopDetailScreenState();
}

class _ShopDetailScreenState extends State<ShopDetailScreen> {
  late Future<({Shop shop, List<ShopItem> items})> _future;

  @override
  void initState() {
    super.initState();
    _future = _load();
  }

  Future<({Shop shop, List<ShopItem> items})> _load() async {
    final shop = await widget.repository.getShop(widget.shopId);
    if (shop == null) {
      throw StateError('Shop not found');
    }
    final items = await widget.repository.getShopItems(widget.shopId);
    return (shop: shop, items: items);
  }

  Future<void> _openReceipt(File file) async {
    await showDialog<void>(
      context: context,
      builder: (context) {
        return Dialog(
          insetPadding: const EdgeInsets.all(16),
          child: InteractiveViewer(
            child: Image.file(file, fit: BoxFit.contain),
          ),
        );
      },
    );
  }

  Future<void> _openProduct(int productId) async {
    await Navigator.of(context).push<void>(
      MaterialPageRoute(
        builder: (_) => ProductDetailScreen(
          repository: widget.repository,
          productId: productId,
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return Scaffold(
      appBar: AppBar(title: const Text('Shopping trip')),
      body: FutureBuilder(
        future: _future,
        builder: (context, snapshot) {
          if (snapshot.hasError) {
            return Center(
              child: Text(
                'Could not load this trip.',
                style: theme.textTheme.bodyLarge,
              ),
            );
          }
          if (!snapshot.hasData) {
            return const Center(child: CircularProgressIndicator());
          }

          final shop = snapshot.data!.shop;
          final items = snapshot.data!.items;
          final receipt = shop.receiptImagePath;
          final receiptFile =
              receipt == null ? null : File(receipt);
          final hasReceipt =
              receiptFile != null && receiptFile.existsSync();

          return ListView(
            padding: const EdgeInsets.fromLTRB(16, 8, 16, 32),
            children: [
              Text(shop.supermarket, style: theme.textTheme.headlineMedium),
              const SizedBox(height: 4),
              Text(
                formatDate(shop.shoppedAt),
                style: theme.textTheme.bodyLarge,
              ),
              if (hasReceipt) ...[
                const SizedBox(height: 16),
                GestureDetector(
                  onTap: () => _openReceipt(receiptFile),
                  child: ClipRRect(
                    borderRadius: BorderRadius.circular(16),
                    child: Image.file(
                      receiptFile,
                      height: 180,
                      width: double.infinity,
                      fit: BoxFit.cover,
                      cacheWidth: 900,
                    ),
                  ),
                ),
              ],
              const SizedBox(height: 24),
              Text('Products', style: theme.textTheme.titleMedium),
              const SizedBox(height: 8),
              for (final item in items)
                ListTile(
                  contentPadding: EdgeInsets.zero,
                  title: Text(item.name),
                  subtitle: item.quantity == null
                      ? null
                      : Text(
                          '${item.quantity} × ${formatEuro(item.unitPrice ?? 0)}',
                        ),
                  trailing: Text(
                    formatEuro(item.price),
                    style: theme.textTheme.titleMedium,
                  ),
                  onTap: () => _openProduct(item.productId),
                ),
              const Divider(),
              ListTile(
                contentPadding: EdgeInsets.zero,
                title: Text('Total', style: theme.textTheme.titleMedium),
                trailing: Text(
                  formatEuro(shop.total),
                  style: theme.textTheme.titleLarge,
                ),
              ),
            ],
          );
        },
      ),
    );
  }
}