import "package:flutter/material.dart";
import "package:google_fonts/google_fonts.dart";

import "../demo_identity.dart";
import "../services/responsable_service.dart";
import "../theme/ensup_colors.dart";
import "../widgets/brand_corners.dart";
import "../widgets/ensup_top_bar.dart";

class ResponsableScreen extends StatefulWidget {
  const ResponsableScreen({super.key});

  @override
  State<ResponsableScreen> createState() => _ResponsableScreenState();
}

class _ResponsableScreenState extends State<ResponsableScreen> {
  late Future<_ResponsableData> _future = _charger();
  int _onglet = 0;
  bool _transitionEnCours = false;

  Future<_ResponsableData> _charger() async {
    final dashboard = await ResponsableService.dashboard();
    final emprunts = await ResponsableService.emprunts();
    final materiels = await ResponsableService.materiels();
    final anomalies = await ResponsableService.anomalies();
    final notifications = await ResponsableService.notifications();
    final historique = await ResponsableService.historique();

    return _ResponsableData(
      dashboard: dashboard,
      emprunts: emprunts,
      materiels: materiels,
      anomalies: anomalies,
      notifications: notifications,
      historique: historique,
    );
  }

  void _rafraichir() {
    setState(() => _future = _charger());
  }

  Future<void> _changerStatut(Map<String, dynamic> anomalie) async {
    final prochain = _prochainStatut(anomalie["statut"] as String?);
    if (prochain == null || _transitionEnCours) {
      return;
    }

    setState(() => _transitionEnCours = true);
    try {
      await ResponsableService.changerStatutAnomalie(
        anomalie["id"] as int,
        prochain,
      );
      _rafraichir();
    } catch (error) {
      if (!mounted) return;
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(SnackBar(content: Text(error.toString())));
    } finally {
      if (mounted) {
        setState(() => _transitionEnCours = false);
      }
    }
  }

  Future<void> _marquerNotificationsLues() async {
    try {
      await ResponsableService.marquerNotificationsLues();
      _rafraichir();
    } catch (error) {
      if (!mounted) return;
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(SnackBar(content: Text(error.toString())));
    }
  }

  String? _prochainStatut(String? statut) {
    return switch (statut) {
      "DETECTEE" => "EN_COURS_TRAITEMENT",
      "EN_COURS_TRAITEMENT" => "RESOLUE",
      "RESOLUE" => "CLOTUREE",
      _ => null,
    };
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: EnsupColors.soft,
      body: Stack(
        children: [
          Center(
            child: ConstrainedBox(
              constraints: const BoxConstraints(maxWidth: 1320, maxHeight: 860),
              child: Container(
                margin: const EdgeInsets.all(24),
                decoration: BoxDecoration(
                  color: Colors.white,
                  borderRadius: BorderRadius.circular(16),
                  boxShadow: [
                    BoxShadow(
                      color: EnsupColors.text.withValues(alpha: 0.14),
                      blurRadius: 60,
                      offset: const Offset(0, 18),
                    ),
                  ],
                ),
                clipBehavior: Clip.antiAlias,
                child: Column(
                  children: [
                    EnsupTopBar(
                      brandText: "EME Responsable",
                      campusTag: DemoIdentity.loginCampusTag,
                      userName: "Karim Benali",
                      userInitials: "KB",
                      onBack: () => Navigator.of(context).pop(),
                    ),
                    Expanded(
                      child: FutureBuilder<_ResponsableData>(
                        future: _future,
                        builder: (context, snapshot) {
                          if (snapshot.connectionState !=
                              ConnectionState.done) {
                            return const Center(
                              child: CircularProgressIndicator(),
                            );
                          }
                          if (snapshot.hasError) {
                            return _Erreur(
                              message: snapshot.error.toString(),
                              onRetry: _rafraichir,
                            );
                          }
                          return _contenu(snapshot.data!);
                        },
                      ),
                    ),
                  ],
                ),
              ),
            ),
          ),
          const Positioned.fill(child: BrandCorners()),
        ],
      ),
    );
  }

  Widget _contenu(_ResponsableData data) {
    final vues = [
      _VueDashboard(data: data),
      _VueListe(
        titre: "Emprunts",
        items: data.emprunts,
        builder: _empruntTile,
        searchableText: (item) {
          final etudiant = Map<String, dynamic>.from(item["etudiant"] as Map);
          final materiel = Map<String, dynamic>.from(item["materiel"] as Map);
          return "${materiel["nom"]} ${materiel["reference"]} ${etudiant["prenom"]} ${etudiant["nom"]} ${item["statut"]}";
        },
      ),
      _VueListe(
        titre: "Stock",
        items: data.materiels,
        builder: _materielTile,
        searchableText: (item) {
          final categorie = Map<String, dynamic>.from(item["categorie"] as Map);
          return "${item["nom"]} ${item["reference"]} ${item["statut"]} ${categorie["nom"]}";
        },
      ),
      _VueListe(
        titre: "Anomalies",
        items: data.anomalies,
        builder: _anomalieTile,
        searchableText: (item) {
          final materiel = Map<String, dynamic>.from(item["materiel"] as Map);
          return "${item["type"]} ${item["description"]} ${item["statut"]} ${materiel["nom"]}";
        },
      ),
      _VueListe(
        titre: "Notifications",
        items: data.notifications,
        builder: _notificationTile,
        action: OutlinedButton.icon(
          onPressed: _marquerNotificationsLues,
          icon: const Icon(Icons.done_all, size: 16),
          label: const Text("Tout marquer lu"),
        ),
        searchableText: (item) => "${item["titre"]} ${item["message"]}",
      ),
      _VueListe(
        titre: "Historique",
        items: data.historique,
        builder: _historiqueTile,
        action: OutlinedButton.icon(
          onPressed: () {
            ScaffoldMessenger.of(context).showSnackBar(
              const SnackBar(
                content: Text(
                  "Export disponible via /api/responsable/historique/export.csv",
                ),
              ),
            );
          },
          icon: const Icon(Icons.download_outlined, size: 16),
          label: const Text("Export CSV"),
        ),
        searchableText: (item) => "${item["action"]} ${item["description"]}",
      ),
    ];

    return Column(
      children: [
        _Onglets(
          index: _onglet,
          labels: const [
            "Dashboard",
            "Emprunts",
            "Stock",
            "Anomalies",
            "Notifications",
            "Historique",
          ],
          onChanged: (index) => setState(() => _onglet = index),
        ),
        Expanded(child: vues[_onglet]),
      ],
    );
  }

  Widget _empruntTile(Map<String, dynamic> item) {
    final etudiant = Map<String, dynamic>.from(item["etudiant"] as Map);
    final materiel = Map<String, dynamic>.from(item["materiel"] as Map);
    return _InfoTile(
      icon: Icons.assignment_outlined,
      title: "${materiel["nom"]}",
      subtitle:
          "${etudiant["prenom"]} ${etudiant["nom"]} · retour prévu ${_date(item["dateRetourPrevue"])}",
      meta: "Emprunt #${item["id"]}",
      trailing: _StatusBadge("${item["statut"]}"),
    );
  }

  Widget _materielTile(Map<String, dynamic> item) {
    final categorie = Map<String, dynamic>.from(item["categorie"] as Map);
    return _InfoTile(
      icon: Icons.inventory_2_outlined,
      title: "${item["nom"]}",
      subtitle:
          "${item["reference"]} · ${categorie["nom"]} · ${item["etatGeneral"]}",
      meta: "${item["marque"]} ${item["modele"]}",
      trailing: _StatusBadge("${item["statut"]}"),
    );
  }

  Widget _anomalieTile(Map<String, dynamic> item) {
    final materiel = Map<String, dynamic>.from(item["materiel"] as Map);
    final prochain = _prochainStatut(item["statut"] as String?);
    return _InfoTile(
      icon: Icons.report_problem_outlined,
      title: "${item["type"]} · ${materiel["nom"]}",
      subtitle: "${item["description"]}",
      meta: "Détectée le ${_date(item["dateDetection"])}",
      trailing: prochain == null
          ? _StatusBadge("${item["statut"]}")
          : FilledButton(
              onPressed: _transitionEnCours ? null : () => _changerStatut(item),
              child: Text(_statusLabel(prochain)),
            ),
    );
  }

  Widget _notificationTile(Map<String, dynamic> item) {
    return _InfoTile(
      icon: item["lu"] == true
          ? Icons.notifications_none
          : Icons.notifications_active_outlined,
      title: "${item["titre"]}",
      subtitle: "${item["message"]}",
      meta: _date(item["dateCreation"]),
      trailing: _StatusBadge(item["lu"] == true ? "LUE" : "NON_LUE"),
    );
  }

  Widget _historiqueTile(Map<String, dynamic> item) {
    final utilisateur = Map<String, dynamic>.from(item["utilisateur"] as Map);
    return _InfoTile(
      icon: Icons.history,
      title: _actionLabel("${item["action"]}"),
      subtitle: "${item["description"]}",
      meta:
          "${_date(item["dateAction"])} · ${utilisateur["prenom"]} ${utilisateur["nom"]}",
      trailing: const Icon(Icons.chevron_right, color: EnsupColors.muted),
    );
  }

  String _date(Object? value) {
    if (value == null) return "-";
    final parsed = DateTime.tryParse(value.toString());
    if (parsed == null) return value.toString();
    return "${parsed.day.toString().padLeft(2, "0")}/"
        "${parsed.month.toString().padLeft(2, "0")}/${parsed.year}";
  }
}

String _statusLabel(String statut) {
  return switch (statut) {
    "DISPONIBLE" => "Disponible",
    "EMPRUNTE" => "Emprunté",
    "NON_CONFORME" => "Non conforme",
    "DETERIORE" => "Détérioré",
    "MAINTENANCE" => "Maintenance",
    "INDISPONIBLE" => "Indisponible",
    "EN_COURS" => "En cours",
    "EN_RETARD" => "En retard",
    "CLOTURE" => "Clôturé",
    "RETOUR_NON_CONFORME" => "Retour non conforme",
    "ANNULE" => "Annulé",
    "DETECTEE" => "À traiter",
    "EN_COURS_TRAITEMENT" => "En traitement",
    "RESOLUE" => "Résolue",
    "CLOTUREE" => "Clôturée",
    "LUE" => "Lue",
    "NON_LUE" => "Non lue",
    _ => statut.replaceAll("_", " ").toLowerCase(),
  };
}

String _actionLabel(String action) {
  return switch (action) {
    "CREATION_EMPRUNT" => "Création d'emprunt",
    "CREATION_ANOMALIE" => "Création d'anomalie",
    "TRAITEMENT_ANOMALIE" => "Traitement d'anomalie",
    _ => action.replaceAll("_", " ").toLowerCase(),
  };
}

Color _statusColor(String statut) {
  return switch (statut) {
    "DISPONIBLE" ||
    "CLOTURE" ||
    "RESOLUE" ||
    "CLOTUREE" ||
    "LUE" => EnsupColors.green,
    "EN_RETARD" ||
    "RETOUR_NON_CONFORME" ||
    "NON_CONFORME" ||
    "DETECTEE" ||
    "NON_LUE" => EnsupColors.red,
    "EN_COURS" || "EN_COURS_TRAITEMENT" || "EMPRUNTE" => EnsupColors.cyan,
    "MAINTENANCE" || "INDISPONIBLE" || "DETERIORE" => EnsupColors.purple,
    _ => EnsupColors.blue3,
  };
}

class _ResponsableData {
  const _ResponsableData({
    required this.dashboard,
    required this.emprunts,
    required this.materiels,
    required this.anomalies,
    required this.notifications,
    required this.historique,
  });

  final Map<String, dynamic> dashboard;
  final List<Map<String, dynamic>> emprunts;
  final List<Map<String, dynamic>> materiels;
  final List<Map<String, dynamic>> anomalies;
  final List<Map<String, dynamic>> notifications;
  final List<Map<String, dynamic>> historique;
}

class _VueDashboard extends StatelessWidget {
  const _VueDashboard({required this.data});

  final _ResponsableData data;

  @override
  Widget build(BuildContext context) {
    final kpis = Map<String, dynamic>.from(data.dashboard["kpis"] as Map);
    return SingleChildScrollView(
      padding: const EdgeInsets.all(24),
      child: Wrap(
        spacing: 14,
        runSpacing: 14,
        children: [
          _KpiCard(
            label: "Matériels",
            value: _total(kpis["materiels"]),
            icon: Icons.inventory_2_outlined,
          ),
          _KpiCard(
            label: "Emprunts",
            value: _total(kpis["emprunts"]),
            icon: Icons.assignment_outlined,
          ),
          _KpiCard(
            label: "Anomalies",
            value: _total(kpis["anomalies"]),
            icon: Icons.report_problem_outlined,
          ),
          _KpiCard(
            label: "Notifications",
            value: "${kpis["notificationsNonLues"] ?? 0}",
            icon: Icons.notifications_outlined,
          ),
        ],
      ),
    );
  }

  String _total(Object? repartition) {
    final map = Map<String, dynamic>.from(repartition as Map);
    return "${map["total"] ?? 0}";
  }
}

class _VueListe extends StatefulWidget {
  const _VueListe({
    required this.titre,
    required this.items,
    required this.builder,
    required this.searchableText,
    this.action,
  });

  final String titre;
  final List<Map<String, dynamic>> items;
  final Widget Function(Map<String, dynamic>) builder;
  final String Function(Map<String, dynamic>) searchableText;
  final Widget? action;

  @override
  State<_VueListe> createState() => _VueListeState();
}

class _VueListeState extends State<_VueListe> {
  String _recherche = "";

  @override
  Widget build(BuildContext context) {
    final terme = _recherche.trim().toLowerCase();
    final resultats = terme.isEmpty
        ? widget.items
        : widget.items
              .where(
                (item) =>
                    widget.searchableText(item).toLowerCase().contains(terme),
              )
              .toList();

    return Padding(
      padding: const EdgeInsets.all(24),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              Expanded(
                child: Text(
                  "${widget.titre} (${resultats.length})",
                  style: GoogleFonts.darkerGrotesque(
                    fontSize: 26,
                    fontWeight: FontWeight.w900,
                    color: EnsupColors.text,
                  ),
                ),
              ),
              if (widget.action != null) widget.action!,
            ],
          ),
          const SizedBox(height: 14),
          TextField(
            onChanged: (value) => setState(() => _recherche = value),
            decoration: InputDecoration(
              hintText: "Rechercher",
              prefixIcon: const Icon(Icons.search),
              isDense: true,
              filled: true,
              fillColor: EnsupColors.soft,
              border: OutlineInputBorder(
                borderRadius: BorderRadius.circular(8),
                borderSide: const BorderSide(color: EnsupColors.line),
              ),
            ),
          ),
          const SizedBox(height: 14),
          Expanded(
            child: resultats.isEmpty
                ? const _EmptyState()
                : ListView.separated(
                    itemCount: resultats.length,
                    separatorBuilder: (_, _) => const SizedBox(height: 10),
                    itemBuilder: (_, index) => widget.builder(resultats[index]),
                  ),
          ),
        ],
      ),
    );
  }
}

class _Onglets extends StatelessWidget {
  const _Onglets({
    required this.index,
    required this.labels,
    required this.onChanged,
  });

  final int index;
  final List<String> labels;
  final ValueChanged<int> onChanged;

  @override
  Widget build(BuildContext context) {
    return Container(
      width: double.infinity,
      padding: const EdgeInsets.fromLTRB(20, 16, 20, 8),
      decoration: const BoxDecoration(
        color: EnsupColors.soft,
        border: Border(bottom: BorderSide(color: EnsupColors.line)),
      ),
      child: SingleChildScrollView(
        scrollDirection: Axis.horizontal,
        child: Row(
          children: List.generate(labels.length, (i) {
            final selected = i == index;
            return Padding(
              padding: const EdgeInsets.only(right: 8),
              child: ChoiceChip(
                selected: selected,
                label: Text(labels[i]),
                onSelected: (_) => onChanged(i),
              ),
            );
          }),
        ),
      ),
    );
  }
}

class _KpiCard extends StatelessWidget {
  const _KpiCard({
    required this.label,
    required this.value,
    required this.icon,
  });

  final String label;
  final String value;
  final IconData icon;

  @override
  Widget build(BuildContext context) {
    return Container(
      width: 210,
      padding: const EdgeInsets.all(18),
      decoration: BoxDecoration(
        border: Border.all(color: EnsupColors.line),
        borderRadius: BorderRadius.circular(8),
      ),
      child: Row(
        children: [
          Icon(icon, color: EnsupColors.blue3),
          const SizedBox(width: 12),
          Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                value,
                style: GoogleFonts.darkerGrotesque(
                  fontSize: 30,
                  fontWeight: FontWeight.w900,
                ),
              ),
              Text(
                label,
                style: GoogleFonts.titilliumWeb(
                  fontSize: 13,
                  color: EnsupColors.muted,
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

class _InfoTile extends StatelessWidget {
  const _InfoTile({
    required this.icon,
    required this.title,
    required this.subtitle,
    required this.trailing,
    this.meta,
  });

  final IconData icon;
  final String title;
  final String subtitle;
  final Widget trailing;
  final String? meta;

  @override
  Widget build(BuildContext context) {
    return Container(
      padding: const EdgeInsets.all(14),
      decoration: BoxDecoration(
        color: Colors.white,
        border: Border.all(color: EnsupColors.line),
        borderRadius: BorderRadius.circular(8),
      ),
      child: Row(
        children: [
          Icon(icon, color: EnsupColors.teal),
          const SizedBox(width: 12),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Text(
                  title,
                  maxLines: 1,
                  overflow: TextOverflow.ellipsis,
                  style: GoogleFonts.darkerGrotesque(
                    fontSize: 19,
                    fontWeight: FontWeight.w800,
                  ),
                ),
                Text(subtitle, maxLines: 2, overflow: TextOverflow.ellipsis),
                if (meta != null) ...[
                  const SizedBox(height: 4),
                  Text(
                    meta!,
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                    style: GoogleFonts.titilliumWeb(
                      fontSize: 12,
                      color: EnsupColors.muted,
                    ),
                  ),
                ],
              ],
            ),
          ),
          const SizedBox(width: 12),
          trailing,
        ],
      ),
    );
  }
}

class _StatusBadge extends StatelessWidget {
  const _StatusBadge(this.statut);

  final String statut;

  @override
  Widget build(BuildContext context) {
    final color = _statusColor(statut);
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 6),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.1),
        borderRadius: BorderRadius.circular(999),
        border: Border.all(color: color.withValues(alpha: 0.18)),
      ),
      child: Text(
        _statusLabel(statut),
        style: TextStyle(
          fontSize: 12,
          fontWeight: FontWeight.w700,
          color: color,
        ),
      ),
    );
  }
}

class _EmptyState extends StatelessWidget {
  const _EmptyState();

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Text(
        "Aucun résultat",
        style: GoogleFonts.titilliumWeb(color: EnsupColors.muted),
      ),
    );
  }
}

class _Erreur extends StatelessWidget {
  const _Erreur({required this.message, required this.onRetry});

  final String message;
  final VoidCallback onRetry;

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: [
          Text(message, textAlign: TextAlign.center),
          const SizedBox(height: 12),
          OutlinedButton.icon(
            onPressed: onRetry,
            icon: const Icon(Icons.refresh),
            label: const Text("Réessayer"),
          ),
        ],
      ),
    );
  }
}