petitspas/frontend/lib/utils/parent_registration_payload.dart

import 'dart:convert';

import '../models/user_registration_data.dart';

/// Construction du body `POST /auth/register/parent` à partir du state d'inscription.
/// Aligné sur [RegisterParentCompletDto] (backend).
class ParentRegistrationPayload {
  ParentRegistrationPayload._();

  static final RegExp _phoneFr = RegExp(r'^(\+33|0)[1-9](\d{2}){4}$');

  /// Retourne un message d'erreur utilisateur, ou `null` si le formulaire est cohérent.
  static String? validateForApi(UserRegistrationData d) {
    final p1 = d.parent1;
    if (p1.email.trim().isEmpty) {
      return 'L’email du parent principal est requis.';
    }
    if (p1.firstName.trim().length < 2) {
      return 'Le prénom du parent principal doit contenir au moins 2 caractères.';
    }
    if (p1.lastName.trim().length < 2) {
      return 'Le nom du parent principal doit contenir au moins 2 caractères.';
    }
    final tel = _normalizePhone(p1.phone);
    if (!_phoneFr.hasMatch(tel)) {
      return 'Le numéro de téléphone du parent principal n’est pas valide (ex. 0612345678).';
    }
    if (!d.cguAccepted) {
      return 'Vous devez accepter les CGU et la politique de confidentialité.';
    }
    if (d.children.isEmpty) {
      return 'Au moins un enfant est requis.';
    }

    final p2 = d.parent2;
    if (p2 != null) {
      final any = p2.email.trim().isNotEmpty ||
          p2.firstName.trim().isNotEmpty ||
          p2.lastName.trim().isNotEmpty ||
          p2.phone.trim().isNotEmpty;
      if (any) {
        if (p2.email.trim().isEmpty ||
            p2.firstName.trim().length < 2 ||
            p2.lastName.trim().length < 2) {
          return 'Les informations du co-parent sont incomplètes (email, prénom et nom requis).';
        }
        if (p2.email.trim().toLowerCase() == p1.email.trim().toLowerCase()) {
          return 'L’email du co-parent doit être différent de celui du parent principal.';
        }
        final tel2 = _normalizePhone(p2.phone);
        if (tel2.isNotEmpty && !_phoneFr.hasMatch(tel2)) {
          return 'Le numéro de téléphone du co-parent n’est pas valide.';
        }
      }
    }

    for (var i = 0; i < d.children.length; i++) {
      final c = d.children[i];
      final label = 'Enfant ${i + 1}';
      if (c.isUnbornChild) {
        final due = _ddMmYyyyToIso(c.dob);
        if (due == null) {
          return '$label : indiquez une date de naissance prévisionnelle.';
        }
      } else {
        if (c.firstName.trim().length < 2) {
          return '$label : le prénom doit contenir au moins 2 caractères.';
        }
        final birth = _ddMmYyyyToIso(c.dob);
        if (birth == null) {
          return '$label : indiquez une date de naissance valide.';
        }
      }
    }

    return null;
  }

  static Map<String, dynamic> toJson(UserRegistrationData d) {
    final p1 = d.parent1;
    final tel = _normalizePhone(p1.phone);

    final body = <String, dynamic>{
      'email': p1.email.trim(),
      'prenom': p1.firstName.trim(),
      'nom': p1.lastName.trim(),
      'telephone': tel,
      'acceptation_cgu': d.cguAccepted,
      'acceptation_privacy': d.cguAccepted,
    };

    _putIfNonEmpty(body, 'adresse', p1.address.trim());
    _putIfNonEmpty(body, 'code_postal', p1.postalCode.trim());
    _putIfNonEmpty(body, 'ville', p1.city.trim());

    final p2 = d.parent2;
    if (p2 != null &&
        p2.email.trim().isNotEmpty &&
        p2.firstName.trim().length >= 2 &&
        p2.lastName.trim().length >= 2) {
      final tel2 = _normalizePhone(p2.phone);
      final sameAddr = p2.address.trim() == p1.address.trim() &&
          p2.postalCode.trim() == p1.postalCode.trim() &&
          p2.city.trim() == p1.city.trim();

      body['co_parent_email'] = p2.email.trim();
      body['co_parent_prenom'] = p2.firstName.trim();
      body['co_parent_nom'] = p2.lastName.trim();
      body['co_parent_meme_adresse'] = sameAddr;
      if (tel2.isNotEmpty) {
        body['co_parent_telephone'] = tel2;
      }
      if (!sameAddr) {
        _putIfNonEmpty(body, 'co_parent_adresse', p2.address.trim());
        _putIfNonEmpty(body, 'co_parent_code_postal', p2.postalCode.trim());
        _putIfNonEmpty(body, 'co_parent_ville', p2.city.trim());
      }
    }

    if (d.motivationText.trim().isNotEmpty) {
      body['presentation_dossier'] = d.motivationText.trim();
    }

    body['enfants'] = d.children.asMap().entries.map((e) {
      return _childToJson(e.value, e.key, d.parent1.lastName.trim());
    }).toList();

    return body;
  }

  static Map<String, dynamic> _childToJson(ChildData c, int index, String parentNom) {
    final map = <String, dynamic>{
      'genre': 'F',
      'grossesse_multiple': c.multipleBirth,
    };

    final prenom = c.firstName.trim();
    if (prenom.length >= 2) {
      map['prenom'] = prenom;
    }

    final nom = c.lastName.trim();
    if (nom.length >= 2) {
      map['nom'] = nom;
    } else if (parentNom.length >= 2) {
      map['nom'] = parentNom;
    }

    if (c.isUnbornChild) {
      final due = _ddMmYyyyToIso(c.dob);
      if (due != null) {
        map['date_previsionnelle_naissance'] = due;
      }
    } else {
      final birth = _ddMmYyyyToIso(c.dob);
      if (birth != null) {
        map['date_naissance'] = birth;
      }
    }

    final photo = _childPhotoBase64(c, index, prenom);
    if (photo != null) {
      map['photo_base64'] = photo.$1;
      map['photo_filename'] = photo.$2;
    }

    return map;
  }

  /// (`dataUrl`, `filename`) ou `null` si pas de fichier lisible.
  static (String, String)? _childPhotoBase64(ChildData c, int index, String prenom) {
    final file = c.imageFile;
    if (file == null) return null;
    try {
      if (!file.existsSync()) return null;
      final bytes = file.readAsBytesSync();
      if (bytes.isEmpty) return null;
      final b64 = base64Encode(bytes);
      final safeName = prenom.isNotEmpty
          ? '${prenom.toLowerCase().replaceAll(RegExp(r'[^a-z0-9]+'), '_')}.jpg'
          : 'enfant_${index + 1}.jpg';
      return ('data:image/jpeg;base64,$b64', safeName);
    } catch (_) {
      return null;
    }
  }

  static void _putIfNonEmpty(Map<String, dynamic> m, String key, String value) {
    if (value.isNotEmpty) {
      m[key] = value;
    }
  }

  static String _normalizePhone(String raw) {
    var s = raw.replaceAll(RegExp(r'\s'), '');
    if (s.startsWith('0033')) {
      s = '+33${s.substring(4)}';
    }
    return s;
  }

  /// `jj/mm/aaaa` → `aaaa-mm-jj`, ou `null` si invalide.
  static String? _ddMmYyyyToIso(String ddMmYyyy) {
    if (ddMmYyyy.isEmpty) return null;
    final parts = ddMmYyyy.split('/');
    if (parts.length != 3) return null;
    final day = int.tryParse(parts[0]);
    final month = int.tryParse(parts[1]);
    final year = int.tryParse(parts[2]);
    if (day == null || month == null || year == null) return null;
    if (month < 1 || month > 12 || day < 1 || day > 31) return null;
    return '${year.toString().padLeft(4, '0')}-${month.toString().padLeft(2, '0')}-${day.toString().padLeft(2, '0')}';
  }
}