import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:intl/intl.dart';

import '../models/purchase_order.dart';
import '../providers/achats_provider.dart';

class PurchaseOrderDetailScreen extends StatelessWidget {
  final PurchaseOrder order;
  const PurchaseOrderDetailScreen({super.key, required this.order});

  @override
  Widget build(BuildContext context) {
    final fmt = NumberFormat.currency(locale: 'fr_TN', symbol: 'TND', decimalDigits: 3);
    final statusColor = Color(order.statutColor);

    return Scaffold(
      backgroundColor: const Color(0xFFF5F7FA),
      appBar: AppBar(
        backgroundColor: Colors.white,
        elevation: 0,
        title: Text(order.reference ?? '—',
            style: const TextStyle(fontWeight: FontWeight.bold)),
        actions: [
          if (order.peutReceptionner)
            Padding(
              padding: const EdgeInsets.only(right: 12),
              child: ElevatedButton.icon(
                onPressed: () => _confirmReceive(context),
                icon: const Icon(Icons.inventory_outlined, size: 18),
                label: const Text('Réceptionner'),
                style: ElevatedButton.styleFrom(
                  backgroundColor: const Color(0xFF8B5CF6),
                  foregroundColor: Colors.white,
                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
                ),
              ),
            ),
        ],
      ),
      body: ListView(
        padding: const EdgeInsets.all(16),
        children: [
          Container(
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: statusColor.withOpacity(0.1),
              borderRadius: BorderRadius.circular(12),
              border: Border.all(color: statusColor.withOpacity(0.3)),
            ),
            child: Row(
              children: [
                Icon(Icons.circle, color: statusColor, size: 10),
                const SizedBox(width: 8),
                Text(order.statutLabel,
                    style: TextStyle(color: statusColor, fontWeight: FontWeight.bold, fontSize: 14)),
              ],
            ),
          ),
          const SizedBox(height: 16),
          _InfoCard(children: [
            _InfoRow(label: 'Fournisseur', value: order.fournisseur?.raisonSociale ?? '—'),
            _InfoRow(label: 'Date commande', value: order.dateCommande),
            if (order.dateLivraisonPrevue != null)
              _InfoRow(label: 'Livraison prévue', value: order.dateLivraisonPrevue!),
            if (order.notes != null && order.notes!.isNotEmpty)
              _InfoRow(label: 'Notes', value: order.notes!),
          ]),
          const SizedBox(height: 16),
          const Text('Lignes de commande',
              style: TextStyle(fontWeight: FontWeight.w700, fontSize: 14)),
          const SizedBox(height: 8),
          ...order.lignes.map((l) => _LigneCard(ligne: l, fmt: fmt)),
          const SizedBox(height: 16),
          Container(
            padding: const EdgeInsets.all(16),
            decoration: BoxDecoration(
              color: Colors.white,
              borderRadius: BorderRadius.circular(12),
              boxShadow: [BoxShadow(color: Colors.black.withOpacity(0.05), blurRadius: 8, offset: const Offset(0, 2))],
            ),
            child: Column(
              children: [
                _TotalRow(label: 'Total HT', value: fmt.format(order.totalHT)),
                _TotalRow(label: 'TVA (19%)', value: fmt.format(order.totalTVA)),
                const Divider(),
                _TotalRow(label: 'Total TTC', value: fmt.format(order.totalTTC),
                    bold: true, color: const Color(0xFF8B5CF6)),
              ],
            ),
          ),
          const SizedBox(height: 32),
        ],
      ),
    );
  }

  void _confirmReceive(BuildContext context) {
    showDialog(
      context: context,
      builder: (_) => AlertDialog(
        title: const Text('Confirmer la réception ?'),
        content: Text(
            'Réceptionner toutes les lignes de ${order.reference} ?\n\nLe stock sera incrémenté automatiquement.'),
        actions: [
          TextButton(onPressed: () => Navigator.pop(context), child: const Text('Annuler')),
          ElevatedButton(
            style: ElevatedButton.styleFrom(backgroundColor: const Color(0xFF8B5CF6)),
            onPressed: () async {
              Navigator.pop(context);
              final err = await context.read<AchatsProvider>().receive(order.id!, order.lignes);
              if (context.mounted) {
                if (err == null) {
                  Navigator.pop(context);
                  ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
                    content: Text('Réception enregistrée — stock mis à jour'),
                    backgroundColor: Colors.green,
                  ));
                } else {
                  ScaffoldMessenger.of(context)
                      .showSnackBar(SnackBar(content: Text(err), backgroundColor: Colors.red));
                }
              }
            },
            child: const Text('Confirmer', style: TextStyle(color: Colors.white)),
          ),
        ],
      ),
    );
  }
}

class _InfoCard extends StatelessWidget {
  final List<Widget> children;
  const _InfoCard({required this.children});
  @override
  Widget build(BuildContext context) => Container(
        padding: const EdgeInsets.all(16),
        decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.circular(12),
          boxShadow: [BoxShadow(color: Colors.black.withOpacity(0.04), blurRadius: 8, offset: const Offset(0, 2))],
        ),
        child: Column(children: children),
      );
}

class _InfoRow extends StatelessWidget {
  final String label;
  final String value;
  const _InfoRow({required this.label, required this.value});
  @override
  Widget build(BuildContext context) => Padding(
        padding: const EdgeInsets.symmetric(vertical: 4),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            SizedBox(width: 130,
                child: Text(label, style: TextStyle(color: Colors.grey[600], fontSize: 13))),
            Expanded(child: Text(value,
                style: const TextStyle(fontWeight: FontWeight.w500, fontSize: 13))),
          ],
        ),
      );
}

class _LigneCard extends StatelessWidget {
  final PurchaseOrderLine ligne;
  final NumberFormat fmt;
  const _LigneCard({required this.ligne, required this.fmt});
  @override
  Widget build(BuildContext context) => Container(
        margin: const EdgeInsets.only(bottom: 8),
        padding: const EdgeInsets.all(12),
        decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.circular(10),
          boxShadow: [BoxShadow(color: Colors.black.withOpacity(0.04), blurRadius: 6, offset: const Offset(0, 1))],
        ),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(ligne.article?.designation ?? '—',
                style: const TextStyle(fontWeight: FontWeight.w600, fontSize: 13)),
            const SizedBox(height: 4),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text(
                  '${ligne.quantiteCommandee} ${ligne.article?.uniteMesure ?? ''} × ${fmt.format(ligne.prixUnitaireHT)}',
                  style: TextStyle(color: Colors.grey[600], fontSize: 12),
                ),
                Text(fmt.format(ligne.montantTTC ?? ligne.montantTTCCalc),
                    style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 13, color: Color(0xFF8B5CF6))),
              ],
            ),
            if (ligne.quantiteRecue > 0)
              Text('Reçu : ${ligne.quantiteRecue}',
                  style: const TextStyle(color: Color(0xFF10B981), fontSize: 11)),
          ],
        ),
      );
}

class _TotalRow extends StatelessWidget {
  final String label;
  final String value;
  final bool bold;
  final Color? color;
  const _TotalRow({required this.label, required this.value, this.bold = false, this.color});
  @override
  Widget build(BuildContext context) => Padding(
        padding: const EdgeInsets.symmetric(vertical: 3),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceBetween,
          children: [
            Text(label, style: TextStyle(color: Colors.grey[600], fontSize: 13)),
            Text(value, style: TextStyle(
                fontWeight: bold ? FontWeight.bold : FontWeight.normal,
                fontSize: bold ? 16 : 13,
                color: color ?? const Color(0xFF374151))),
          ],
        ),
      );
}