feat(meters): establish checkpoint C1 meter foundation

app_new/core/models/__init__.py

@@ -12,7 +12,7 @@ from .maintenance import (
 from .company import Company, Part, PartStockMovement, Alert, Service
 from .planning import (
     WorkSchedule, WorkScheduleTemplate, AnnualTimeConfig, TimeEntry, CollegeClosure, ClosureSchedule, ClosureWorkDay, PersonalLeave, Training, TrainingParticipant,
-    Meter, MeterReading, Consumable, ConsumableUsage, EquipmentConsumable,
+    Meter, MeterReading, MeterReadingCorrection, Consumable, ConsumableUsage, EquipmentConsumable,
     PreventiveTask, PreventiveTaskConsumable, ScheduledTask, TaskExecutionSegment,
     TechnicianAvailability, AdminTask, ZoneAccessRule
 )
@@ -36,7 +36,7 @@ __all__ = [
     'Lot', 'LotTask', 'LotService', 'WorkRequest', 'WorkRequestQuote', 'WorkRequestEvent',
     'Company', 'Part', 'PartStockMovement', 'InterventionPart', 'Alert', 'Service',
     'WorkSchedule', 'WorkScheduleTemplate', 'AnnualTimeConfig', 'TimeEntry', 'CollegeClosure', 'ClosureSchedule', 'ClosureWorkDay', 'PersonalLeave', 'Training', 'TrainingParticipant',
-    'Meter', 'MeterReading', 'Consumable', 'ConsumableUsage', 'EquipmentConsumable',
+    'Meter', 'MeterReading', 'MeterReadingCorrection', 'Consumable', 'ConsumableUsage', 'EquipmentConsumable',
     'PreventiveTask', 'PreventiveTaskConsumable', 'ScheduledTask', 'TaskExecutionSegment',
     'TechnicianAvailability', 'AdminTask', 'ZoneAccessRule',
     'AppSettings', 'AuditLog', 'TemplateAuditMark',

app_new/core/models/planning.py

@@ -243,15 +243,39 @@ class TrainingParticipant(db.Model):
 
 
 class Meter(db.Model):
-    """Compteur sur un équipement."""
+    """Compteur physique rattaché à un élément du patrimoine.
+
+    ``equipment_id`` reste le rattachement historique, mais un compteur peut
+    désormais être porté directement par un bâtiment, une zone, un local ou
+    un logement.  Les rattachements sont explicites afin de conserver
+    l'intégrité référentielle SQL.
+    """
     __tablename__ = "meters"
+    __table_args__ = (
+        db.CheckConstraint(
+            "(equipment_id IS NOT NULL) + (building_id IS NOT NULL) + "
+            "(zone_id IS NOT NULL) + (room_id IS NOT NULL) + "
+            "(housing_unit_id IS NOT NULL) = 1",
+            name="ck_meters_one_scope",
+        ),
+    )
     
     id = db.Column(db.Integer, primary_key=True)
-    equipment_id = db.Column(db.Integer, db.ForeignKey("equipments.id"), nullable=False)
+    equipment_id = db.Column(db.Integer, db.ForeignKey("equipments.id"), nullable=True, index=True)
+    building_id = db.Column(db.Integer, db.ForeignKey("buildings.id"), nullable=True, index=True)
+    zone_id = db.Column(db.Integer, db.ForeignKey("zones.id"), nullable=True, index=True)
+    room_id = db.Column(db.Integer, db.ForeignKey("rooms.id"), nullable=True, index=True)
+    housing_unit_id = db.Column(db.Integer, db.ForeignKey("housing_units.id"), nullable=True, index=True)
+
+    parent_id = db.Column(db.Integer, db.ForeignKey("meters.id"), nullable=True, index=True)
+    replaces_meter_id = db.Column(db.Integer, db.ForeignKey("meters.id"), nullable=True, index=True)
     
     name = db.Column(db.String(100), nullable=False)
     meter_type = db.Column(db.String(50), default="hours")
     unit = db.Column(db.String(20), default="h")
+    usage = db.Column(db.String(255), nullable=True)
+    status = db.Column(db.String(30), nullable=False, default="active", server_default="active")
+    remainder_label = db.Column(db.String(255), nullable=True)
     
     current_value = db.Column(db.Float, default=0)
     initial_value = db.Column(db.Float, default=0)
@@ -271,6 +295,12 @@ class Meter(db.Model):
     updated_at = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc), onupdate=lambda: datetime.now(timezone.utc))
     
     equipment = db.relationship("Equipment", backref=db.backref("meters", lazy="dynamic"))
+    building = db.relationship("Building", backref=db.backref("meters", lazy="dynamic"))
+    zone = db.relationship("Zone", backref=db.backref("meters", lazy="dynamic"))
+    room = db.relationship("Room", backref=db.backref("meters", lazy="dynamic"))
+    housing_unit = db.relationship("HousingUnit", backref=db.backref("meters", lazy="dynamic"))
+    parent = db.relationship("Meter", remote_side=[id], foreign_keys=[parent_id], backref=db.backref("children", lazy="dynamic"))
+    replaced_meter = db.relationship("Meter", remote_side=[id], foreign_keys=[replaces_meter_id], backref=db.backref("replacement", uselist=False))
     readings = db.relationship("MeterReading", back_populates="meter", lazy="dynamic")
     
     @property
@@ -310,11 +340,13 @@ class MeterReading(db.Model):
     
     value = db.Column(db.Float, nullable=False)
     reading_date = db.Column(db.DateTime, default=lambda: datetime.now(timezone.utc))
-    read_by_id = db.Column(db.Integer, db.ForeignKey("users.id"))
+    read_by_id = db.Column(db.Integer, db.ForeignKey("users.id", ondelete="SET NULL"))
     
     notes = db.Column(db.Text)
     is_reset = db.Column(db.Boolean, nullable=False, default=False)
     reset_reason = db.Column(db.String(255), nullable=True)
+    photo_filename = db.Column(db.String(255), nullable=True)
+    photo_path = db.Column(db.String(500), nullable=True)
     
     meter = db.relationship("Meter", back_populates="readings")
     read_by = db.relationship("User")
@@ -323,6 +355,22 @@ class MeterReading(db.Model):
         return f"<MeterReading {self.value}>"
 
 
+class MeterReadingCorrection(db.Model):
+    """Audit immuable de chaque correction d'un relevé existant."""
+    __tablename__ = "meter_reading_corrections"
+
+    id = db.Column(db.Integer, primary_key=True)
+    reading_id = db.Column(db.Integer, db.ForeignKey("meter_readings.id", ondelete="CASCADE"), nullable=False, index=True)
+    old_value = db.Column(db.Float, nullable=False)
+    new_value = db.Column(db.Float, nullable=False)
+    corrected_by_id = db.Column(db.Integer, db.ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    corrected_at = db.Column(db.DateTime, nullable=False, default=lambda: datetime.now(timezone.utc))
+    reason = db.Column(db.Text, nullable=False)
+
+    reading = db.relationship("MeterReading", backref=db.backref("corrections", lazy="selectin"))
+    corrected_by = db.relationship("User")
+
+
 class Consumable(db.Model):
     """Consommable pour maintenance."""
     __tablename__ = "consumables"

app_new/core/services/meter_service.py

@@ -0,0 +1,178 @@
+"""Services métier communs aux compteurs et à leurs relevés."""
+
+from datetime import datetime, timezone
+from math import isfinite
+
+from ..models.college import Building, HousingUnit, Room, Zone
+from ..models.equipment import Equipment
+from ..models.planning import Meter, MeterReading, MeterReadingCorrection
+from ...extensions import db
+
+
+class MeterDomainError(ValueError):
+    """Erreur de validation métier d'un compteur ou d'un relevé."""
+
+
+SCOPE_MODELS = {
+    "equipment": (Equipment, "equipment_id"),
+    "building": (Building, "building_id"),
+    "zone": (Zone, "zone_id"),
+    "room": (Room, "room_id"),
+    "housing_unit": (HousingUnit, "housing_unit_id"),
+}
+
+
+def _scope_values(**scope_ids):
+    values = {name: value for name, value in scope_ids.items() if value is not None}
+    if len(values) != 1:
+        raise MeterDomainError("Un compteur doit avoir exactement un rattachement patrimoine.")
+    return values
+
+
+def _validate_parent(meter, parent):
+    if parent is None:
+        return
+    if parent.id == meter.id:
+        raise MeterDomainError("Un compteur ne peut pas être son propre parent.")
+    cursor = parent
+    seen = set()
+    while cursor is not None:
+        if cursor.id in seen:
+            raise MeterDomainError("La hiérarchie des compteurs contient déjà un cycle.")
+        seen.add(cursor.id)
+        if cursor.id == meter.id:
+            raise MeterDomainError("Cette relation créerait un cycle de compteurs.")
+        cursor = cursor.parent
+
+
+def validate_meter_scope(meter):
+    """Valide le rattachement principal et la hiérarchie d'un compteur."""
+    with db.session.no_autoflush:
+        _scope_values(
+            equipment_id=meter.equipment_id,
+            building_id=meter.building_id,
+            zone_id=meter.zone_id,
+            room_id=meter.room_id,
+            housing_unit_id=meter.housing_unit_id,
+        )
+        _validate_parent(meter, meter.parent)
+    return meter
+
+
+def create_meter(*, name, meter_type="hours", unit="h", usage=None,
+                 initial_value=0, current_value=None, parent=None,
+                 remainder_label=None, status="active", replaces_meter_id=None,
+                 warning_threshold=None, critical_threshold=None, maintenance_interval=None,
+                 last_maintenance_value=None, reading_interval_days=None, commit=True,
+                 **scope_ids):
+    """Crée un compteur avec les mêmes règles pour toutes les routes."""
+    name = (name or "").strip()
+    if not name:
+        raise MeterDomainError("Le nom du compteur est obligatoire.")
+    scope = _scope_values(**scope_ids)
+    model = Meter(name=name, meter_type=meter_type or "hours", unit=unit or "h",
+                  usage=usage, initial_value=initial_value or 0,
+                  current_value=initial_value if current_value is None else current_value,
+                  remainder_label=remainder_label, status=status or "active",
+                  replaces_meter_id=replaces_meter_id,
+                  warning_threshold=warning_threshold, critical_threshold=critical_threshold,
+                  maintenance_interval=maintenance_interval, last_maintenance_value=last_maintenance_value,
+                  reading_interval_days=reading_interval_days,
+                  **scope)
+    if parent is not None:
+        model.parent = parent
+    validate_meter_scope(model)
+    db.session.add(model)
+    if commit:
+        db.session.commit()
+    return model
+
+
+def _latest_reading(meter):
+    return (MeterReading.query.filter_by(meter_id=meter.id)
+            .order_by(MeterReading.reading_date.desc(), MeterReading.id.desc())
+            .first())
+
+
+def record_meter_reading(*, meter, value, user_id, reading_date=None, notes=None,
+                         is_reset=False, reset_reason=None,
+                         photo_filename=None, photo_path=None, commit=True):
+    """Enregistre une vraie mesure et synchronise l'index courant."""
+    try:
+        value = float(value)
+    except (TypeError, ValueError):
+        raise MeterDomainError("La valeur du relevé est invalide.")
+    if not isfinite(value):
+        raise MeterDomainError("La valeur du relevé est invalide.")
+    reset_reason = (reset_reason or "").strip()
+    if is_reset and not reset_reason:
+        raise MeterDomainError("Le motif de remise à zéro est obligatoire.")
+    if value < (meter.current_value or 0) and not is_reset:
+        raise MeterDomainError("Un relevé inférieur exige une remise à zéro explicite et justifiée.")
+
+    reading_date = reading_date or datetime.now(timezone.utc)
+    reading = MeterReading(
+        meter=meter, value=value, reading_date=reading_date, read_by_id=user_id,
+        notes=notes, is_reset=bool(is_reset), reset_reason=reset_reason or None,
+        photo_filename=photo_filename, photo_path=photo_path,
+    )
+    meter.current_value = value
+    meter.last_reading_date = reading_date.date()
+    if is_reset:
+        meter.initial_value = value
+        meter.last_maintenance_value = value
+    db.session.add(reading)
+    if commit:
+        db.session.commit()
+    return reading
+
+
+def correct_meter_reading(*, reading, new_value, user_id, reason, commit=True):
+    """Corrige un relevé en conservant une trace relationnelle complète."""
+    reason = (reason or "").strip()
+    if not reason:
+        raise MeterDomainError("La justification de correction est obligatoire.")
+    try:
+        new_value = float(new_value)
+    except (TypeError, ValueError):
+        raise MeterDomainError("La valeur corrigée est invalide.")
+    if not isfinite(new_value):
+        raise MeterDomainError("La valeur corrigée est invalide.")
+    old_value = reading.value
+    if old_value == new_value:
+        raise MeterDomainError("La correction doit modifier la valeur.")
+    db.session.add(MeterReadingCorrection(
+        reading=reading, old_value=old_value, new_value=new_value,
+        corrected_by_id=user_id, reason=reason,
+    ))
+    reading.value = new_value
+    meter = reading.meter
+    latest = _latest_reading(meter)
+    if latest is not None:
+        meter.current_value = latest.value
+        meter.last_reading_date = latest.reading_date.date()
+    if commit:
+        db.session.commit()
+    return reading
+
+
+def replace_meter(*, old_meter, name, user_id=None, commit=True, **kwargs):
+    """Crée un nouveau compteur et clôt explicitement l'ancien."""
+    if old_meter.status == "replaced":
+        raise MeterDomainError("Ce compteur est déjà remplacé.")
+    scope = {
+        key: getattr(old_meter, key)
+        for key in ("equipment_id", "building_id", "zone_id", "room_id", "housing_unit_id")
+    }
+    new_meter = create_meter(
+        name=name, meter_type=kwargs.pop("meter_type", old_meter.meter_type),
+        unit=kwargs.pop("unit", old_meter.unit), usage=kwargs.pop("usage", old_meter.usage),
+        initial_value=kwargs.pop("initial_value", 0), current_value=kwargs.pop("current_value", 0),
+        replaces_meter_id=old_meter.id, commit=False, **scope,
+    )
+    old_meter.status = "replaced"
+    old_meter.is_active = False
+    db.session.add(new_meter)
+    if commit:
+        db.session.commit()
+    return new_meter

app_new/equipments/meters.py

@@ -7,6 +7,7 @@ from ..core.models.equipment import Equipment, EquipmentCategory, EquipmentDocum
 from ..core.models.college import Room, Building, RoomType, Zone
 from ..core.models.maintenance import Lot, Intervention
 from ..core.models.planning import Meter, MeterReading, Consumable, EquipmentConsumable, ScheduledTask
+from ..core.services.meter_service import MeterDomainError, create_meter, record_meter_reading
 from app_new.constants import EQUIPMENT_STATUSES
 
 def _empty_to_none(v):
@@ -74,8 +75,7 @@ def add_meter(id):
     """Ajouter un compteur à un équipement."""
     equipment = Equipment.query.get_or_404(id)
     
-    meter = Meter(
-        equipment_id=id,
+    meter = create_meter(
         name=request.form.get('name'),
         meter_type=request.form.get('meter_type', 'hours'),
         unit=request.form.get('unit', 'h'),
@@ -84,10 +84,9 @@ def add_meter(id):
         warning_threshold=float(request.form.get('warning_threshold')) if request.form.get('warning_threshold') else None,
         critical_threshold=float(request.form.get('critical_threshold')) if request.form.get('critical_threshold') else None,
         maintenance_interval=float(request.form.get('maintenance_interval')) if request.form.get('maintenance_interval') else None,
-        last_maintenance_value=float(request.form.get('last_maintenance_value')) if request.form.get('last_maintenance_value') else None
+        last_maintenance_value=float(request.form.get('last_maintenance_value')) if request.form.get('last_maintenance_value') else None,
+        equipment_id=id,
     )
-    db.session.add(meter)
-    db.session.commit()
     
     return jsonify({'success': True, 'meter_id': meter.id})
 
@@ -100,18 +99,21 @@ def add_meter_reading(id):
     meter_id = data.get('meter_id')
     value = data.get('value')
     
-    meter = Meter.query.filter_by(id=meter_id, equipment_id=id).first_or_404()
-    
-    reading = MeterReading(
-        meter_id=meter_id,
-        value=value,
-        read_by_id=current_user.id
+    meter = Meter.query.get_or_404(meter_id)
+    if meter.equipment_id != id:
+        from flask import abort
+        abort(404)
+    try:
+        reading = record_meter_reading(
+            meter=meter, value=value, user_id=current_user.id,
+            notes=data.get('notes'), is_reset=bool(data.get('is_reset')),
+            reset_reason=data.get('reset_reason'), commit=True,
         )
-    meter.current_value = value
-    db.session.add(reading)
-    db.session.commit()
+    except MeterDomainError as exc:
+        db.session.rollback()
+        return jsonify({'success': False, 'error': str(exc)}), 400
 
-    return jsonify({'success': True})
+    return jsonify({'success': True, 'reading_id': reading.id})
 
 
 # ==================== CONSOMMABLES ====================

app_new/meters/routes.py

@@ -2,11 +2,21 @@
 Meters Routes - GMAO Collège
 Gestion des compteurs
 """
-from flask import Blueprint, render_template, request, redirect, url_for, flash, jsonify
+from flask import Blueprint, render_template, request, redirect, url_for, flash, jsonify, current_app, send_file, abort
 from flask_login import login_required, current_user
+from datetime import datetime
+from pathlib import Path
+from uuid import uuid4
+from werkzeug.utils import secure_filename
+from sqlalchemy.orm import joinedload
 from app_new.extensions import db
 from app_new.core.models.planning import Meter, MeterReading
 from app_new.core.models.equipment import Equipment
+from app_new.core.models.college import Building, HousingUnit, Room, Zone
+from app_new.core.services.meter_service import (
+    MeterDomainError, correct_meter_reading, create_meter, record_meter_reading,
+    replace_meter,
+)
 
 meters_bp = Blueprint('meters', __name__, template_folder='templates')
 
@@ -15,8 +25,7 @@ meters_bp = Blueprint('meters', __name__, template_folder='templates')
 @login_required
 def index():
     """Liste de tous les compteurs."""
-    # Récupérer tous les compteurs avec leur équipement
-    meters = Meter.query.join(Equipment).order_by(Equipment.name, Meter.name).all()
+    meters = Meter.query.order_by(Meter.name).all()
     
     # Statistiques
     total_count = len(meters)
@@ -32,12 +41,49 @@ def index():
                          maintenance_count=maintenance_count)
 
 
+@meters_bp.route('/new', methods=['GET', 'POST'])
+@login_required
+def new():
+    """Créer un compteur rattaché à un élément patrimoine."""
+    if request.method == 'POST':
+        try:
+            scope_type = request.form.get('scope_type')
+            scope_id = request.form.get('scope_id', type=int)
+            scope_key = {
+                'equipment': 'equipment_id', 'building': 'building_id', 'zone': 'zone_id',
+                'room': 'room_id', 'housing_unit': 'housing_unit_id',
+            }.get(scope_type)
+            if not scope_key or not scope_id:
+                raise MeterDomainError('Un rattachement patrimoine est obligatoire.')
+            meter = create_meter(
+                name=(request.form.get('name') or '').strip(),
+                meter_type=request.form.get('meter_type') or 'hours',
+                unit=(request.form.get('unit') or '').strip() or 'h',
+                usage=(request.form.get('usage') or '').strip() or None,
+                initial_value=request.form.get('initial_value', type=float, default=0),
+                parent=Meter.query.get(request.form.get('parent_id', type=int)) if request.form.get('parent_id', type=int) else None,
+                remainder_label=(request.form.get('remainder_label') or '').strip() or None,
+                **{scope_key: scope_id},
+            )
+            flash(f'Compteur « {meter.name} » créé.', 'success')
+            return redirect(url_for('meters.detail', meter_id=meter.id))
+        except MeterDomainError as exc:
+            db.session.rollback()
+            flash(str(exc), 'danger')
+    return render_template(
+        'meters/new.html', equipments=Equipment.query.filter_by(is_group=False).order_by(Equipment.name).all(),
+        buildings=Building.query.order_by(Building.name).all(), zones=Zone.query.order_by(Zone.name).all(),
+        rooms=Room.query.order_by(Room.name).all(), housing_units=HousingUnit.query.order_by(HousingUnit.name).all(),
+        parents=Meter.query.filter(Meter.status != 'replaced').order_by(Meter.name).all(),
+    )
+
+
 @meters_bp.route('/<int:meter_id>')
 @login_required
 def detail(meter_id):
     """Détails d'un compteur avec historique des relevés."""
     meter = Meter.query.get_or_404(meter_id)
-    readings = MeterReading.query.filter_by(meter_id=meter_id)\
+    readings = MeterReading.query.options(joinedload(MeterReading.read_by)).filter_by(meter_id=meter_id)\
         .order_by(MeterReading.reading_date.desc()).limit(50).all()
     
     return render_template('meters/detail.html', meter=meter, readings=readings)
@@ -49,36 +95,35 @@ def add_reading(meter_id):
     """Ajouter un relevé à un compteur."""
     meter = Meter.query.get_or_404(meter_id)
     
-    try:
-        value = float(request.form.get('value'))
-    except (TypeError, ValueError):
-        return jsonify({'success': False, 'error': 'Valeur invalide'}), 400
-    
     is_reset = request.form.get('is_reset') == '1'
     reset_reason = (request.form.get('reset_reason') or '').strip()
-    if value < (meter.current_value or 0) and not (is_reset and reset_reason):
-        flash('Un relevé inférieur exige de cocher « remise à zéro » et de saisir un motif.', 'danger')
+    photo_filename = photo_path = None
+    photo = request.files.get('photo')
+    if photo and photo.filename:
+        allowed = {'jpg', 'jpeg', 'png', 'gif'}
+        if '.' not in photo.filename or photo.filename.rsplit('.', 1)[1].lower() not in allowed:
+            flash('La photo doit être une image JPG, PNG ou GIF.', 'danger')
             return redirect(url_for('meters.detail', meter_id=meter_id))
-    if is_reset and not reset_reason:
-        flash('Le motif de remise à zéro est obligatoire.', 'danger')
-        return redirect(url_for('meters.detail', meter_id=meter_id))
-
-    reading = MeterReading(
-        meter_id=meter_id,
-        value=value,
-        read_by_id=current_user.id,
-        notes=request.form.get('notes', ''), is_reset=is_reset, reset_reason=reset_reason or None,
+        photo_filename = secure_filename(photo.filename)
+        stored_name = f'{uuid4().hex}_{photo_filename}'
+        upload_dir = Path(current_app.config.get('UPLOAD_FOLDER', 'uploads')) / 'meter-readings'
+        upload_dir.mkdir(parents=True, exist_ok=True)
+        photo_path = str(upload_dir / stored_name)
+        photo.save(photo_path)
+        photo_filename = stored_name
+    try:
+        reading = record_meter_reading(
+            meter=meter, value=request.form.get('value'), user_id=current_user.id,
+            notes=request.form.get('notes', ''), is_reset=is_reset, reset_reason=reset_reason,
+            photo_filename=photo_filename, photo_path=photo_path,
         )
-    meter.current_value = value
-    if is_reset:
-        meter.initial_value = value
-        meter.last_maintenance_value = value
-    meter.updated_at = db.func.now()
-    
-    db.session.add(reading)
-    db.session.commit()
-    
-    flash(f'Relevé enregistré: {value} {meter.unit}', 'success')
+    except MeterDomainError as exc:
+        db.session.rollback()
+        if photo_path:
+            Path(photo_path).unlink(missing_ok=True)
+        flash(str(exc), 'danger')
+        return redirect(url_for('meters.detail', meter_id=meter_id))
+    flash(f'Relevé enregistré: {reading.value} {meter.unit}', 'success')
     return redirect(url_for('meters.detail', meter_id=meter_id))
 
 
@@ -100,7 +145,8 @@ def edit(meter_id):
         meter.maintenance_interval = request.form.get('maintenance_interval', type=float)
         meter.last_maintenance_value = request.form.get('last_maintenance_value', type=float)
         meter.reading_interval_days = request.form.get('reading_interval_days', type=int)
-        meter.current_value = request.form.get('current_value', type=float, default=0)
+        # L'index courant est piloté exclusivement par les relevés. Les
+        # corrections passent par l'historique afin de rester auditées.
         
         # Date du dernier relevé
         last_reading_date = request.form.get('last_reading_date')
@@ -110,9 +156,24 @@ def edit(meter_id):
             meter.last_reading_date = None
         
         # Équipement
-        equipment_id = request.form.get('equipment_id')
-        if equipment_id:
-            meter.equipment_id = int(equipment_id)
+        scope_type = request.form.get('scope_type')
+        scope_id = request.form.get('scope_id', type=int)
+        if scope_type and scope_id:
+            scope_keys = ('equipment_id', 'building_id', 'zone_id', 'room_id', 'housing_unit_id')
+            scope_key = {'equipment': 'equipment_id', 'building': 'building_id', 'zone': 'zone_id', 'room': 'room_id', 'housing_unit': 'housing_unit_id'}.get(scope_type)
+            if scope_key:
+                for key in scope_keys:
+                    setattr(meter, key, scope_id if key == scope_key else None)
+        meter.usage = (request.form.get('usage') or '').strip() or None
+        meter.remainder_label = (request.form.get('remainder_label') or '').strip() or None
+        meter.status = request.form.get('status') or meter.status
+        try:
+            from app_new.core.services.meter_service import validate_meter_scope
+            validate_meter_scope(meter)
+        except MeterDomainError as exc:
+            db.session.rollback()
+            flash(str(exc), 'danger')
+            return redirect(url_for('meters.edit', meter_id=meter_id))
         
         db.session.commit()
         flash('Compteur modifié avec succès', 'success')
@@ -121,5 +182,53 @@ def edit(meter_id):
     return render_template('meters/edit.html',
                           meter=meter, 
                           equipments=equipments,
+                          buildings=Building.query.order_by(Building.name).all(),
+                          zones=Zone.query.order_by(Zone.name).all(),
+                          rooms=Room.query.order_by(Room.name).all(),
+                          housing_units=HousingUnit.query.order_by(HousingUnit.name).all(),
                           timedelta=timedelta,
                           today=date.today())
+
+
+@meters_bp.route('/<int:meter_id>/readings/<int:reading_id>/correct', methods=['POST'])
+@login_required
+def correct_reading(meter_id, reading_id):
+    reading = MeterReading.query.filter_by(id=reading_id, meter_id=meter_id).first_or_404()
+    try:
+        correct_meter_reading(
+            reading=reading, new_value=request.form.get('value'),
+            user_id=current_user.id, reason=request.form.get('reason'),
+        )
+        flash('Relevé corrigé et correction auditée.', 'success')
+    except MeterDomainError as exc:
+        db.session.rollback()
+        flash(str(exc), 'danger')
+    return redirect(url_for('meters.detail', meter_id=meter_id))
+
+
+@meters_bp.route('/<int:meter_id>/readings/<int:reading_id>/photo')
+@login_required
+def reading_photo(meter_id, reading_id):
+    reading = MeterReading.query.filter_by(id=reading_id, meter_id=meter_id).first_or_404()
+    upload_root = Path(current_app.config.get('UPLOAD_FOLDER', 'uploads')).resolve()
+    photo_path = Path(reading.photo_path or '').resolve()
+    if not reading.photo_path or upload_root not in photo_path.parents or not photo_path.is_file():
+        abort(404)
+    return send_file(photo_path, download_name=reading.photo_filename or photo_path.name)
+
+
+@meters_bp.route('/<int:meter_id>/replace', methods=['POST'])
+@login_required
+def replace(meter_id):
+    old_meter = Meter.query.get_or_404(meter_id)
+    try:
+        new_meter = replace_meter(
+            old_meter=old_meter, name=(request.form.get('name') or '').strip(),
+            user_id=current_user.id, meter_type=request.form.get('meter_type'),
+            unit=request.form.get('unit'), usage=request.form.get('usage'),
+        )
+        flash(f'Compteur remplacé par « {new_meter.name} ».', 'success')
+    except MeterDomainError as exc:
+        db.session.rollback()
+        flash(str(exc), 'danger')
+    return redirect(url_for('meters.detail', meter_id=meter_id))

app_new/meters/templates/meters/detail.html

@@ -6,9 +6,7 @@
     <nav aria-label="breadcrumb" class="mb-3">
         <ol class="breadcrumb">
             <li class="breadcrumb-item"><a href="{{ url_for('meters.index') }}">Compteurs</a></li>
-            <li class="breadcrumb-item">
-                <a href="{{ url_for('equipments.detail', id=meter.equipment.id) if meter.equipment else '#' }}">{{ meter.equipment.name if meter.equipment else 'Sans equipement' }}</a>
-            </li>
+            <li class="breadcrumb-item">{% if meter.equipment %}<a href="{{ url_for('equipments.detail', id=meter.equipment.id) }}">{{ meter.equipment.name }}</a>{% elif meter.building %}{{ meter.building.name }}{% elif meter.zone %}{{ meter.zone.name }}{% elif meter.room %}{{ meter.room.name }}{% elif meter.housing_unit %}{{ meter.housing_unit.name }}{% else %}Patrimoine{% endif %}</li>
             <li class="breadcrumb-item active">{{ meter.name }}</li>
         </ol>
     </nav>
@@ -24,13 +22,14 @@
                 </div>
                 <div class="card-body">
                     <dl class="row mb-0">
-                        <dt class="col-sm-5">Équipement</dt>
+                        <dt class="col-sm-5">Rattachement</dt>
                         <dd class="col-sm-7">
-                            <a href="{{ url_for('equipments.detail', id=meter.equipment.id) if meter.equipment else '#' }}">
-                                {{ meter.equipment.name if meter.equipment else 'Sans equipement' }}
-                            </a>
+                            {% if meter.equipment %}Équipement — {{ meter.equipment.name }}{% elif meter.building %}Bâtiment — {{ meter.building.name }}{% elif meter.zone %}Zone — {{ meter.zone.name }}{% elif meter.room %}Local — {{ meter.room.name }}{% elif meter.housing_unit %}Logement — {{ meter.housing_unit.name }}{% endif %}
                         </dd>
 
+                        <dt class="col-sm-5">Usage</dt><dd class="col-sm-7">{{ meter.usage or '—' }}</dd>
+                        <dt class="col-sm-5">Reste sous-compté</dt><dd class="col-sm-7">{{ meter.remainder_label or '—' }}</dd>
+                        
                         <dt class="col-sm-5">Type</dt>
                         <dd class="col-sm-7">{{ meter.meter_type }}</dd>
                         
@@ -112,7 +111,7 @@
                     <i class="bi bi-pencil me-1"></i>Nouveau relevé
                 </div>
                 <div class="card-body">
-                    <form method="POST" action="{{ url_for('meters.add_reading', meter_id=meter.id) }}">
+                    <form method="POST" enctype="multipart/form-data" action="{{ url_for('meters.add_reading', meter_id=meter.id) }}">
                         <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
                         
                         <div class="mb-3">
@@ -123,13 +122,14 @@
                                 <span class="input-group-text">{{ meter.unit }}</span>
                             </div>
                         </div>
-                        <div class="form-check mb-2"><input class="form-check-input" type="checkbox" value="1" name="is_reset" id="is_reset"><label class="form-check-label" for="is_reset">Remise à zéro / remplacement du compteur</label></div>
+                        <div class="form-check mb-2"><input class="form-check-input" type="checkbox" value="1" name="is_reset" id="is_reset"><label class="form-check-label" for="is_reset">Remise à zéro explicite</label></div>
                         <div class="mb-3"><input class="form-control" name="reset_reason" placeholder="Motif obligatoire si remise à zéro"></div>
                         
                         <div class="mb-3">
                             <label for="notes" class="form-label">Notes</label>
                             <textarea class="form-control" id="notes" name="notes" rows="2"></textarea>
                         </div>
+                        <div class="mb-3"><label class="form-label" for="photo">Photo facultative</label><input class="form-control" type="file" id="photo" name="photo" accept="image/jpeg,image/png,image/gif"></div>
                         
                         <button type="submit" class="btn btn-primary w-100">
                             <i class="bi bi-check-lg me-1"></i>Enregistrer
@@ -152,7 +152,7 @@
                                 <th>Valeur</th>
                                 <th>Variation</th>
                                 <th>Par</th>
-                                <th>Notes</th>
+                                <th>Notes / correction</th>
                             </tr>
                         </thead>
                         <tbody>
@@ -173,7 +173,7 @@
                                     {% endif %}
                                 </td>
                                 <td>{{ reading.read_by.username if reading.read_by else '—' }}</td>
-                                <td>{% if reading.is_reset %}<span class="badge bg-warning text-dark">RAZ</span> {{ reading.reset_reason }}{% else %}{{ reading.notes or '—' }}{% endif %}</td>
+                                <td>{% if reading.is_reset %}<span class="badge bg-warning text-dark">RAZ</span> {{ reading.reset_reason }}{% else %}{{ reading.notes or '—' }}{% endif %}{% if reading.photo_path %}<div class="small"><a href="{{ url_for('meters.reading_photo', meter_id=meter.id, reading_id=reading.id) }}">Photo jointe</a></div>{% endif %}<details class="mt-1"><summary class="small">Corriger</summary><form method="post" action="{{ url_for('meters.correct_reading', meter_id=meter.id, reading_id=reading.id) }}" class="d-flex gap-1 mt-1"><input type="hidden" name="csrf_token" value="{{ csrf_token() }}"><input class="form-control form-control-sm" type="number" step="0.01" name="value" value="{{ reading.value }}" aria-label="Nouvelle valeur"><input class="form-control form-control-sm" name="reason" required placeholder="Justification"><button class="btn btn-sm btn-outline-warning">Enregistrer</button></form>{% for correction in reading.corrections %}<div class="small text-muted">{{ correction.old_value }} → {{ correction.new_value }} · {{ correction.reason }}</div>{% endfor %}</details></td>
                             </tr>
                             {% else %}
                             <tr>
@@ -187,6 +187,7 @@
                     </table>
                 </div>
             </div>
+            {% if meter.status != 'replaced' %}<div class="card mt-3"><div class="card-header">Remplacer ce compteur</div><div class="card-body"><form method="post" action="{{ url_for('meters.replace', meter_id=meter.id) }}" class="row g-2"><input type="hidden" name="csrf_token" value="{{ csrf_token() }}"><div class="col-md-5"><input class="form-control" name="name" required placeholder="Nom du nouveau compteur"></div><div class="col-md-3"><input class="form-control" name="meter_type" value="{{ meter.meter_type }}"></div><div class="col-md-2"><input class="form-control" name="unit" value="{{ meter.unit }}"></div><div class="col-md-2"><button class="btn btn-outline-danger w-100">Remplacer</button></div></form></div></div>{% endif %}
         </div>
     </div>
 </div>

app_new/meters/templates/meters/edit.html

@@ -22,14 +22,21 @@
                         <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
                         
                         <div class="mb-3">
-                            <label for="equipment_id" class="form-label">Équipement</label>
-                            <select class="form-select" id="equipment_id" name="equipment_id">
-                                {% for eq in equipments %}
-                                <option value="{{ eq.id }}" {% if meter.equipment_id == eq.id %}selected{% endif %}>
-                                    {{ eq.name }}
-                                    {% if eq.room %}({{ eq.room.name }}){% endif %}
-                                </option>
-                                {% endfor %}
+                            <label for="scope_type" class="form-label">Type de rattachement</label>
+                            <select class="form-select" id="scope_type" name="scope_type">
+                                <option value="equipment" {% if meter.equipment %}selected{% endif %}>Équipement</option>
+                                <option value="building" {% if meter.building %}selected{% endif %}>Bâtiment</option>
+                                <option value="zone" {% if meter.zone %}selected{% endif %}>Zone</option>
+                                <option value="room" {% if meter.room %}selected{% endif %}>Local</option>
+                                <option value="housing_unit" {% if meter.housing_unit %}selected{% endif %}>Logement</option>
+                            </select>
+                            <label for="scope_id" class="form-label mt-2">Élément patrimoine</label>
+                            <select class="form-select" id="scope_id" name="scope_id">
+                                {% for eq in equipments %}<option data-scope="equipment" value="{{ eq.id }}" {% if meter.equipment_id == eq.id %}selected{% endif %}>Équipement — {{ eq.name }}</option>{% endfor %}
+                                {% for item in buildings %}<option data-scope="building" value="{{ item.id }}" {% if meter.building_id == item.id %}selected{% endif %}>Bâtiment — {{ item.name }}</option>{% endfor %}
+                                {% for item in zones %}<option data-scope="zone" value="{{ item.id }}" {% if meter.zone_id == item.id %}selected{% endif %}>Zone — {{ item.name }}</option>{% endfor %}
+                                {% for item in rooms %}<option data-scope="room" value="{{ item.id }}" {% if meter.room_id == item.id %}selected{% endif %}>Local — {{ item.name }}</option>{% endfor %}
+                                {% for item in housing_units %}<option data-scope="housing_unit" value="{{ item.id }}" {% if meter.housing_unit_id == item.id %}selected{% endif %}>Logement — {{ item.name }}</option>{% endfor %}
                             </select>
                         </div>
                         
@@ -59,8 +66,8 @@
                         <div class="mb-3">
                             <label for="current_value" class="form-label">Valeur actuelle</label>
                             <div class="input-group">
-                                <input type="number" step="0.01" class="form-control" id="current_value" name="current_value"
-                                       value="{{ meter.current_value }}">
+                                <input type="number" step="0.01" class="form-control" id="current_value"
+                                       value="{{ meter.current_value }}" readonly>
                                 <span class="input-group-text">{{ meter.unit }}</span>
                             </div>
                         </div>
@@ -165,4 +172,9 @@
         </div>
     </div>
 </div>
+<script>
+const type = document.getElementById('scope_type'), target = document.getElementById('scope_id');
+function filterScopes() { const value = type.value; [...target.options].forEach(o => { o.hidden = o.dataset.scope !== value; }); }
+type.addEventListener('change', filterScopes); filterScopes();
+</script>
 {% endblock %}

app_new/meters/templates/meters/index.html

@@ -9,8 +9,8 @@
             <p class="text-muted mb-0">Suivi des heures de fonctionnement, cycles, et autres métriques</p>
         </div>
         <div>
-            <a href="{{ url_for('planning.meters') }}" class="btn btn-outline-primary">
-                <i class="bi bi-plus-circle me-1"></i>Gestion préventive
+            <a href="{{ url_for('meters.new') }}" class="btn btn-primary">
+                <i class="bi bi-plus-circle me-1"></i>Nouveau compteur
             </a>
         </div>
     </div>
@@ -60,7 +60,7 @@
             <table class="table table-hover mb-0">
                 <thead>
                     <tr>
-                        <th>Équipement</th>
+                        <th>Rattachement</th>
                         <th>Compteur</th>
                         <th>Type</th>
                         <th>Valeur</th>
@@ -75,9 +75,11 @@
                     {% for meter in meters %}
                     <tr class="{{ 'table-warning' if meter.warning_level == 'warning' else '' }}{{ 'table-danger' if meter.warning_level == 'critical' else '' }}">
                         <td>
-                            <a href="{{ url_for('equipments.detail', id=meter.equipment.id) }}">
-                                {{ meter.equipment.name }}
-                            </a>
+                            {% if meter.equipment %}<a href="{{ url_for('equipments.detail', id=meter.equipment.id) }}">{{ meter.equipment.name }}</a>
+                            {% elif meter.building %}Bâtiment — {{ meter.building.name }}
+                            {% elif meter.zone %}Zone — {{ meter.zone.name }}
+                            {% elif meter.room %}Local — {{ meter.room.name }}
+                            {% elif meter.housing_unit %}Logement — {{ meter.housing_unit.name }}{% endif %}
                         </td>
                         <td>
                             <a href="{{ url_for('meters.detail', meter_id=meter.id) }}">

app_new/meters/templates/meters/new.html

@@ -0,0 +1,27 @@
+{% extends "base.html" %}
+{% block title %}Nouveau compteur — GMAO{% endblock %}
+{% block content %}
+<div class="container-fluid">
+  <h1 class="h3 mb-3">Nouveau compteur</h1>
+  <form method="post" class="card">
+    <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
+    <div class="card-body row g-3">
+      <div class="col-md-6"><label class="form-label" for="name">Nom *</label><input class="form-control" id="name" name="name" required></div>
+      <div class="col-md-3"><label class="form-label" for="meter_type">Type</label><input class="form-control" id="meter_type" name="meter_type" value="eau" required></div>
+      <div class="col-md-3"><label class="form-label" for="unit">Unité physique</label><input class="form-control" id="unit" name="unit" value="m³" required></div>
+      <div class="col-12"><label class="form-label" for="usage">Usage mesuré</label><input class="form-control" id="usage" name="usage" placeholder="Ex. alimentation générale"></div>
+      <div class="col-md-6"><label class="form-label" for="scope_type">Rattachement *</label><select class="form-select" id="scope_type" name="scope_type" required><option value="">Choisir…</option><option value="equipment">Équipement</option><option value="building">Bâtiment</option><option value="zone">Zone</option><option value="room">Local</option><option value="housing_unit">Logement</option></select></div>
+      <div class="col-md-6"><label class="form-label" for="scope_id">Élément patrimoine *</label><select class="form-select" id="scope_id" name="scope_id" required><option value="">Choisir…</option>{% for item in equipments %}<option data-scope="equipment" value="{{ item.id }}">Équipement — {{ item.name }}</option>{% endfor %}{% for item in buildings %}<option data-scope="building" value="{{ item.id }}">Bâtiment — {{ item.name }}</option>{% endfor %}{% for item in zones %}<option data-scope="zone" value="{{ item.id }}">Zone — {{ item.name }}</option>{% endfor %}{% for item in rooms %}<option data-scope="room" value="{{ item.id }}">Local — {{ item.name }}</option>{% endfor %}{% for item in housing_units %}<option data-scope="housing_unit" value="{{ item.id }}">Logement — {{ item.name }}</option>{% endfor %}</select></div>
+      <div class="col-md-4"><label class="form-label" for="initial_value">Index initial</label><input class="form-control" type="number" step="0.01" id="initial_value" name="initial_value" value="0"></div>
+      <div class="col-md-4"><label class="form-label" for="parent_id">Compteur parent (facultatif)</label><select class="form-select" id="parent_id" name="parent_id"><option value="">Aucun</option>{% for parent in parents %}<option value="{{ parent.id }}">{{ parent.name }}</option>{% endfor %}</select></div>
+      <div class="col-md-4"><label class="form-label" for="remainder_label">Libellé du reste (facultatif)</label><input class="form-control" id="remainder_label" name="remainder_label" placeholder="Ex. Parties communes"></div>
+    </div>
+    <div class="card-footer"><button class="btn btn-primary">Créer</button> <a class="btn btn-outline-secondary" href="{{ url_for('meters.index') }}">Annuler</a></div>
+  </form>
+</div>
+<script>
+const type = document.getElementById('scope_type'), target = document.getElementById('scope_id');
+function filterScopes() { const value = type.value; [...target.options].forEach(o => { o.hidden = o.value && o.dataset.scope !== value; }); if (target.selectedOptions[0]?.hidden) target.value = ''; }
+type.addEventListener('change', filterScopes); filterScopes();
+</script>
+{% endblock %}

app_new/planning/schedules.py

@@ -675,7 +675,7 @@ def scheduled_detail(id):
 @login_required
 def meters():
     """Liste des compteurs."""
-    meters = Meter.query.order_by(Meter.equipment_id).all()
+    meters = Meter.query.order_by(Meter.name).all()
     return render_template('planning/meters.html', meters=meters)
 
 
@@ -684,7 +684,9 @@ def meters():
 def new_meter():
     """Créer un nouveau compteur."""
     if request.method == 'POST':
-        meter = Meter(
+        from ..core.services.meter_service import create_meter, MeterDomainError
+        try:
+            meter = create_meter(
                 equipment_id=request.form.get('equipment_id', type=int),
                 name=request.form.get('name'),
                 meter_type=request.form.get('meter_type', 'hours'),
@@ -694,10 +696,10 @@ def new_meter():
                 warning_threshold=request.form.get('warning_threshold', type=float),
                 critical_threshold=request.form.get('critical_threshold', type=float),
                 maintenance_interval=request.form.get('maintenance_interval', type=float),
-            is_active=True
             )
-        db.session.add(meter)
-        db.session.commit()
+        except MeterDomainError as exc:
+            flash(str(exc), 'danger')
+            return redirect(url_for('planning.new_meter'))
         flash('Compteur créé', 'success')
         return redirect(url_for('planning.meters'))
     

app_new/planning/templates/planning/meters.html

@@ -4,7 +4,7 @@
 {% block content %}
 <div class="d-flex justify-content-between align-items-center mb-4">
     <h1><i class="bi bi-speedometer2"></i> Compteurs</h1>
-    <a href="{{ url_for('planning.new_meter') }}" class="btn btn-primary">
+    <a href="{{ url_for('meters.new') }}" class="btn btn-primary">
         <i class="bi bi-plus"></i> Nouveau compteur
     </a>
 </div>
@@ -12,7 +12,7 @@
 <table class="table table-hover">
     <thead class="table-light">
         <tr>
-            <th>Équipement</th>
+            <th>Rattachement</th>
             <th>Nom</th>
             <th>Type</th>
             <th>Valeur actuelle</th>
@@ -26,7 +26,7 @@
     <tbody>
         {% for meter in meters %}
         <tr>
-            <td>{{ meter.equipment.name if meter.equipment else '-' }}</td>
+            <td>{% if meter.equipment %}{{ meter.equipment.name }}{% elif meter.building %}Bâtiment — {{ meter.building.name }}{% elif meter.zone %}Zone — {{ meter.zone.name }}{% elif meter.room %}Local — {{ meter.room.name }}{% elif meter.housing_unit %}Logement — {{ meter.housing_unit.name }}{% else %}—{% endif %}</td>
             <td><strong>{{ meter.name }}</strong></td>
             <td><span class="badge bg-secondary">{{ meter.meter_type }}</span></td>
             <td>{{ meter.current_value }} {{ meter.unit }}</td>
@@ -62,7 +62,7 @@
         {% else %}
         <tr>
             <td colspan="9" class="text-center text-muted py-4">
-                Aucun compteur. <a href="{{ url_for('planning.new_meter') }}">Créer le premier</a>
+                Aucun compteur. <a href="{{ url_for('meters.new') }}">Créer le premier</a>
             </td>
         </tr>
         {% endfor %}

migrations/alembic.ini

@@ -1,6 +1,8 @@
 # A generic, single database configuration.
 
 [alembic]
+script_location = migrations
+prepend_sys_path = .
 # template used to generate migration files
 # file_template = %%(rev)s_%%(slug)s
 

migrations/versions/n9c0d1e2f3g4_meter_c1_foundation.py

@@ -0,0 +1,80 @@
+"""Checkpoint C1: socle compteurs, rattachements et relevés audités."""
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = "n9c0d1e2f3g4"
+down_revision = "m8b9c0d1e2f3"
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # Les relevés restent auditables après suppression d'un utilisateur ;
+    # seule la référence vers l'auteur devient NULL.
+    op.drop_constraint("meter_readings_ibfk_2", "meter_readings", type_="foreignkey")
+    op.create_foreign_key(
+        "fk_meter_readings_read_by", "meter_readings", "users",
+        ["read_by_id"], ["id"], ondelete="SET NULL",
+    )
+    op.alter_column("meters", "equipment_id", existing_type=sa.Integer(), nullable=True)
+    for name, target in (
+        ("building_id", "buildings"), ("zone_id", "zones"),
+        ("room_id", "rooms"), ("housing_unit_id", "housing_units"),
+    ):
+        op.add_column("meters", sa.Column(name, sa.Integer(), nullable=True))
+        op.create_index(f"ix_meters_{name}", "meters", [name])
+        op.create_foreign_key(f"fk_meters_{name}", "meters", target, [name], ["id"])
+    op.add_column("meters", sa.Column("parent_id", sa.Integer(), nullable=True))
+    op.add_column("meters", sa.Column("replaces_meter_id", sa.Integer(), nullable=True))
+    op.add_column("meters", sa.Column("usage", sa.String(255), nullable=True))
+    op.add_column("meters", sa.Column("status", sa.String(30), nullable=False, server_default="active"))
+    op.add_column("meters", sa.Column("remainder_label", sa.String(255), nullable=True))
+    for name in ("parent_id", "replaces_meter_id"):
+        op.create_index(f"ix_meters_{name}", "meters", [name])
+        op.create_foreign_key(f"fk_meters_{name}", "meters", "meters", [name], ["id"])
+    op.create_check_constraint(
+        "ck_meters_one_scope", "meters",
+        "(equipment_id IS NOT NULL) + (building_id IS NOT NULL) + "
+        "(zone_id IS NOT NULL) + (room_id IS NOT NULL) + "
+        "(housing_unit_id IS NOT NULL) = 1",
+    )
+    op.add_column("meter_readings", sa.Column("photo_filename", sa.String(255), nullable=True))
+    op.add_column("meter_readings", sa.Column("photo_path", sa.String(500), nullable=True))
+    op.create_table(
+        "meter_reading_corrections",
+        sa.Column("id", sa.Integer(), primary_key=True),
+        sa.Column("reading_id", sa.Integer(), nullable=False),
+        sa.Column("old_value", sa.Float(), nullable=False),
+        sa.Column("new_value", sa.Float(), nullable=False),
+        sa.Column("corrected_by_id", sa.Integer(), nullable=True),
+        sa.Column("corrected_at", sa.DateTime(), nullable=False),
+        sa.Column("reason", sa.Text(), nullable=False),
+        sa.ForeignKeyConstraint(["reading_id"], ["meter_readings.id"], ondelete="CASCADE"),
+        sa.ForeignKeyConstraint(["corrected_by_id"], ["users.id"], ondelete="SET NULL"),
+    )
+    op.create_index("ix_meter_reading_corrections_reading_id", "meter_reading_corrections", ["reading_id"])
+    op.create_index("ix_meter_reading_corrections_corrected_by_id", "meter_reading_corrections", ["corrected_by_id"])
+
+
+def downgrade():
+    op.drop_constraint("fk_meter_readings_read_by", "meter_readings", type_="foreignkey")
+    op.create_foreign_key("meter_readings_ibfk_2", "meter_readings", "users", ["read_by_id"], ["id"])
+    op.drop_index("ix_meter_reading_corrections_corrected_by_id", table_name="meter_reading_corrections")
+    op.drop_index("ix_meter_reading_corrections_reading_id", table_name="meter_reading_corrections")
+    op.drop_table("meter_reading_corrections")
+    op.drop_column("meter_readings", "photo_path")
+    op.drop_column("meter_readings", "photo_filename")
+    op.drop_constraint("ck_meters_one_scope", "meters", type_="check")
+    for name in ("replaces_meter_id", "parent_id"):
+        op.drop_constraint(f"fk_meters_{name}", "meters", type_="foreignkey")
+        op.drop_index(f"ix_meters_{name}", table_name="meters")
+        op.drop_column("meters", name)
+    for name in ("remainder_label", "status", "usage"):
+        op.drop_column("meters", name)
+    for name, target in reversed((("building_id", "buildings"), ("zone_id", "zones"), ("room_id", "rooms"), ("housing_unit_id", "housing_units"))):
+        op.drop_constraint(f"fk_meters_{name}", "meters", type_="foreignkey")
+        op.drop_index(f"ix_meters_{name}", table_name="meters")
+        op.drop_column("meters", name)
+    op.alter_column("meters", "equipment_id", existing_type=sa.Integer(), nullable=False)