Simplify battery management: bulk add, device-level auto-install, mass operations

- Replace single-battery add form with bulk add (brand + count, auto-generated labels)
- Add device-level install form: specify brand+qty pairs, system autoselects available batteries
- Add bulk actions on dashboard: retire, delete, unassign, change brand (checkbox multi-select)
- Keep per-battery assign route for special cases (e.g. known low-capacity battery)
- Remove unique constraint on Battery.label (labels are now auto-generated)
- Add *.snapshot to .gitignore for DB snapshot files
- Rewrite tests: 35 passing (11 new tests for bulk-add, device-install, bulk-actions)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -4,6 +4,7 @@ __pycache__/
 *.db
 *.db-shm
 *.db-wal
+*.snapshot
 instance/
 .pytest_cache/
 *.egg-info/

app.py

@@ -1,5 +1,5 @@
 from flask import Flask, render_template, redirect, url_for, request, flash, abort
-from sqlalchemy import create_engine
+from sqlalchemy import create_engine, func
 from sqlalchemy.orm import scoped_session, sessionmaker
 
 from models import Base, Battery, Device
@@ -37,31 +37,27 @@ def create_app(config_object="config"):
     @app.route("/battery/add", methods=["GET", "POST"])
     def battery_add():
         if request.method == "POST":
-            label = request.form.get("label", "").strip()
             brand = request.form.get("brand", "").strip()
-            status = request.form.get("status", "available").strip()
             notes = request.form.get("notes", "").strip() or None
+            try:
+                count = max(1, min(50, int(request.form.get("count", 1) or 1)))
+            except (ValueError, TypeError):
+                count = 1
 
-            if not label or not brand:
+            if not brand:
-                flash("Label and brand are required.", "error")
+                flash("Brand is required.", "error")
-                return render_template("battery_add.html"), 400
-
-            if status not in ("available", "installed", "retired"):
-                status = "available"
-
-            if db.query(Battery).filter_by(label=label).first():
-                flash(f"A battery with label '{label}' already exists.", "error")
                 return render_template("battery_add.html",
-                                       form_label=label, form_brand=brand,
+                                       form_brand="", form_count=1, form_notes=notes or ""), 400
-                                       form_status=status, form_notes=notes or ""), 400
 
-            battery = Battery(label=label, brand=brand, status=status, notes=notes)
+            existing = db.query(func.count(Battery.id)).filter_by(brand=brand).scalar()
-            db.add(battery)
+            for i in range(count):
+                label = f"{brand} {existing + i + 1:03d}"
+                db.add(Battery(label=label, brand=brand, status="available", notes=notes))
             db.commit()
-            flash(f"Battery {label} added.", "success")
+            flash(f"Added {count} {brand} batter{'y' if count == 1 else 'ies'}.", "success")
             return redirect(url_for("dashboard"))
 
-        return render_template("battery_add.html")
+        return render_template("battery_add.html", form_count=1)
 
     # ------------------------------------------------------------------ #
     # Battery — detail
@@ -190,6 +186,54 @@ def create_app(config_object="config"):
             return redirect(url_for("dashboard"))
         return render_template("battery_delete.html", battery=battery)
 
+    # ------------------------------------------------------------------ #
+    # Battery — bulk action
+    # ------------------------------------------------------------------ #
+
+    @app.route("/battery/bulk-action", methods=["POST"])
+    def battery_bulk_action():
+        ids = request.form.getlist("battery_ids", type=int)
+        if not ids:
+            flash("No batteries selected.", "error")
+            return redirect(url_for("dashboard"))
+
+        batteries = db.query(Battery).filter(Battery.id.in_(ids)).all()
+        action = request.form.get("action")
+        n = len(batteries)
+
+        if action == "retire":
+            for b in batteries:
+                b.status = "retired"
+                b.device_id = None
+            db.commit()
+            flash(f"Retired {n} batter{'y' if n == 1 else 'ies'}.", "success")
+        elif action == "delete":
+            for b in batteries:
+                db.delete(b)
+            db.commit()
+            flash(f"Deleted {n} batter{'y' if n == 1 else 'ies'}.", "success")
+        elif action == "unassign":
+            count = sum(1 for b in batteries if b.is_installed())
+            for b in batteries:
+                if b.is_installed():
+                    b.status = "available"
+                    b.device_id = None
+            db.commit()
+            flash(f"Unassigned {count} batter{'y' if count == 1 else 'ies'}.", "success")
+        elif action == "set_brand":
+            new_brand = request.form.get("new_brand", "").strip()
+            if not new_brand:
+                flash("Brand name is required.", "error")
+                return redirect(url_for("dashboard"))
+            for b in batteries:
+                b.brand = new_brand
+            db.commit()
+            flash(f"Updated brand to '{new_brand}' for {n} batter{'y' if n == 1 else 'ies'}.", "success")
+        else:
+            flash("Unknown action.", "error")
+
+        return redirect(url_for("dashboard"))
+
     # ------------------------------------------------------------------ #
     # Devices — list
     # ------------------------------------------------------------------ #
@@ -248,6 +292,79 @@ def create_app(config_object="config"):
             abort(404)
         return render_template("device_detail.html", device=device)
 
+    # ------------------------------------------------------------------ #
+    # Devices — install batteries
+    # ------------------------------------------------------------------ #
+
+    @app.route("/device/<int:device_id>/install", methods=["POST"])
+    def device_install(device_id):
+        device = db.get(Device, device_id)
+        if device is None:
+            abort(404)
+
+        brands = request.form.getlist("brand[]")
+        qtys_raw = request.form.getlist("qty[]")
+
+        pairs = []
+        for brand, qty_raw in zip(brands, qtys_raw):
+            brand = brand.strip()
+            try:
+                qty = int(qty_raw)
+            except (ValueError, TypeError):
+                qty = 0
+            if brand and qty > 0:
+                pairs.append((brand, qty))
+
+        if not pairs:
+            flash("No batteries specified.", "error")
+            return redirect(url_for("device_detail", device_id=device_id))
+
+        free_slots = device.battery_slots - device.installed_count()
+        total_requested = sum(qty for _, qty in pairs)
+        if total_requested > free_slots:
+            flash(
+                f"Only {free_slots} slot(s) free, but {total_requested} requested.",
+                "error",
+            )
+            return redirect(url_for("device_detail", device_id=device_id))
+
+        # Validate availability before writing anything
+        for brand, qty in pairs:
+            available_count = (
+                db.query(func.count(Battery.id))
+                .filter_by(brand=brand, status="available")
+                .scalar()
+            )
+            if available_count < qty:
+                flash(
+                    f"Need {qty} {brand}, but only {available_count} available.",
+                    "error",
+                )
+                return redirect(url_for("device_detail", device_id=device_id))
+
+        # All checks passed — perform installs
+        total_installed = 0
+        for brand, qty in pairs:
+            batch = (
+                db.query(Battery)
+                .filter_by(brand=brand, status="available")
+                .order_by(Battery.id)
+                .limit(qty)
+                .all()
+            )
+            for b in batch:
+                b.status = "installed"
+                b.device_id = device.id
+                total_installed += 1
+
+        db.commit()
+        flash(
+            f"Installed {total_installed} batter{'y' if total_installed == 1 else 'ies'}"
+            f" into {device.name}.",
+            "success",
+        )
+        return redirect(url_for("device_detail", device_id=device_id))
+
     # ------------------------------------------------------------------ #
     # Devices — delete
     # ------------------------------------------------------------------ #

models.py

@@ -31,7 +31,7 @@ class Battery(Base):
     __tablename__ = "battery"
 
     id = Column(Integer, primary_key=True, autoincrement=True)
-    label = Column(String(50), nullable=False, unique=True)
+    label = Column(String(50), nullable=False)
     brand = Column(String(100), nullable=False)
     status = Column(String(20), nullable=False, default="available")
     device_id = Column(Integer, ForeignKey("device.id", ondelete="SET NULL"), nullable=True)

templates/battery_add.html

@@ -1,17 +1,11 @@
 {% extends "base.html" %}
-{% block title %}Add Battery — Battery Tracker{% endblock %}
+{% block title %}Add Batteries — Battery Tracker{% endblock %}
 
 {% block content %}
-<h1>Add Battery</h1>
+<h1>Add Batteries</h1>
 
 <div class="card">
   <form method="post" action="{{ url_for('battery_add') }}">
-    <div class="form-group">
-      <label for="label">Label <span class="text-danger">*</span></label>
-      <input type="text" id="label" name="label" value="{{ form_label|default('') }}"
-             placeholder="e.g. ENL-17" required>
-    </div>
-
     <div class="form-group">
       <label for="brand">Brand <span class="text-danger">*</span></label>
       <input type="text" id="brand" name="brand" value="{{ form_brand|default('') }}"
@@ -19,21 +13,18 @@
     </div>
 
     <div class="form-group">
-      <label for="status">Initial Status</label>
+      <label for="count">Quantity</label>
-      <select id="status" name="status">
+      <input type="number" id="count" name="count" value="{{ form_count|default(1) }}" min="1" max="50">
-        <option value="available" {% if form_status|default('available') == 'available' %}selected{% endif %}>Available</option>
+      <small class="text-muted">Labels are auto-generated (e.g. Eneloop 001, Eneloop 002)</small>
-        <option value="installed" {% if form_status|default('') == 'installed' %}selected{% endif %}>Installed</option>
-        <option value="retired"   {% if form_status|default('') == 'retired' %}selected{% endif %}>Retired</option>
-      </select>
     </div>
 
     <div class="form-group">
       <label for="notes">Notes</label>
-      <textarea id="notes" name="notes" placeholder="Optional notes…">{{ form_notes|default('') }}</textarea>
+      <textarea id="notes" name="notes" placeholder="Optional notes applied to all batteries…">{{ form_notes|default('') }}</textarea>
     </div>
 
     <div class="form-actions">
-      <button class="btn btn-primary" type="submit">Add Battery</button>
+      <button class="btn btn-primary" type="submit">Add Batteries</button>
       <a class="btn btn-secondary" href="{{ url_for('dashboard') }}">Cancel</a>
     </div>
   </form>

templates/dashboard.html

@@ -29,60 +29,101 @@
 </div>
 
 <div class="card">
-  <div class="table-wrap">
+  <form method="post" action="{{ url_for('battery_bulk_action') }}" id="bulk-form">
-    <table>
+
-      <thead>
+    <div id="bulk-toolbar" style="display:none;margin-bottom:0.75rem;padding:0.6rem 0.75rem;background:#f1f5f9;border-radius:6px;display:none;align-items:center;gap:0.5rem;flex-wrap:wrap;">
-        <tr>
+      <span id="selected-count" style="font-size:0.85rem;color:#64748b;margin-right:0.25rem;"></span>
-          <th>Label</th>
+      <button class="btn btn-sm btn-warning" name="action" value="unassign" type="submit">Unassign</button>
-          <th>Brand</th>
+      <button class="btn btn-sm btn-secondary" name="action" value="retire" type="submit">Retire</button>
-          <th>Status</th>
+      <button class="btn btn-sm btn-danger" name="action" value="delete" type="submit"
-          <th>Assigned To</th>
+              onclick="return confirm('Permanently delete selected batteries?')">Delete</button>
-          <th>Actions</th>
+      <span style="display:flex;gap:0.35rem;align-items:center;">
-        </tr>
+        <input type="text" name="new_brand" id="new-brand-input" placeholder="New brand name"
-      </thead>
+               style="padding:0.25rem 0.5rem;font-size:0.85rem;border:1px solid #cbd5e1;border-radius:4px;width:160px;">
-      <tbody>
+        <button class="btn btn-sm btn-primary" name="action" value="set_brand" type="submit">Change Brand</button>
-        {% for b in batteries %}
+      </span>
-        <tr>
+    </div>
-          <td><a href="{{ url_for('battery_detail', battery_id=b.id) }}"><strong>{{ b.label }}</strong></a></td>
+
-          <td>{{ b.brand }}</td>
+    <div class="table-wrap">
-          <td>
+      <table>
-            <span class="badge badge-{{ b.status }}">{{ b.status|capitalize }}</span>
+        <thead>
-          </td>
+          <tr>
-          <td>
+            <th style="width:1.5rem;"><input type="checkbox" id="select-all" title="Select all"></th>
-            {% if b.device %}
+            <th>Label</th>
-              <a href="{{ url_for('device_detail', device_id=b.device.id) }}">{{ b.device.name }}</a>
+            <th>Brand</th>
-              {% if b.device.has_mixed_brands() %}
+            <th>Status</th>
-                <span class="badge badge-warning" title="Mixed brands in this device">⚠ mixed</span>
+            <th>Assigned To</th>
+            <th>Actions</th>
+          </tr>
+        </thead>
+        <tbody>
+          {% for b in batteries %}
+          <tr>
+            <td><input type="checkbox" name="battery_ids" value="{{ b.id }}" class="row-cb"></td>
+            <td><a href="{{ url_for('battery_detail', battery_id=b.id) }}"><strong>{{ b.label }}</strong></a></td>
+            <td>{{ b.brand }}</td>
+            <td>
+              <span class="badge badge-{{ b.status }}">{{ b.status|capitalize }}</span>
+            </td>
+            <td>
+              {% if b.device %}
+                <a href="{{ url_for('device_detail', device_id=b.device.id) }}">{{ b.device.name }}</a>
+                {% if b.device.has_mixed_brands() %}
+                  <span class="badge badge-warning" title="Mixed brands in this device">⚠ mixed</span>
+                {% endif %}
+              {% else %}
+                <span class="text-muted">—</span>
               {% endif %}
-            {% else %}
+            </td>
-              <span class="text-muted">—</span>
+            <td style="white-space:nowrap;">
-            {% endif %}
+              <a class="btn btn-sm btn-secondary" href="{{ url_for('battery_detail', battery_id=b.id) }}">View</a>
-          </td>
-          <td style="white-space:nowrap;">
-            <a class="btn btn-sm btn-secondary" href="{{ url_for('battery_detail', battery_id=b.id) }}">View</a>
 
-            {% if b.is_available() %}
+              {% if b.is_available() %}
-              <a class="btn btn-sm btn-primary" href="{{ url_for('battery_assign', battery_id=b.id) }}">Assign</a>
+                <a class="btn btn-sm btn-primary" href="{{ url_for('battery_assign', battery_id=b.id) }}">Assign</a>
-            {% endif %}
+              {% endif %}
 
-            {% if b.is_installed() %}
+              {% if b.is_installed() %}
-              <form class="inline" method="post" action="{{ url_for('battery_unassign', battery_id=b.id) }}">
+                <button class="btn btn-sm btn-warning" type="submit"
-                <button class="btn btn-sm btn-warning" type="submit">Unassign</button>
+                        formaction="{{ url_for('battery_unassign', battery_id=b.id) }}">Unassign</button>
-              </form>
+              {% endif %}
-            {% endif %}
 
-            {% if not b.is_retired() %}
+              {% if not b.is_retired() %}
-              <form class="inline" method="post" action="{{ url_for('battery_retire', battery_id=b.id) }}">
+                <button class="btn btn-sm btn-secondary" type="submit"
-                <button class="btn btn-sm btn-secondary" type="submit">Retire</button>
+                        formaction="{{ url_for('battery_retire', battery_id=b.id) }}">Retire</button>
-              </form>
+              {% endif %}
-            {% endif %}
+            </td>
-          </td>
+          </tr>
-        </tr>
+          {% else %}
-        {% else %}
+          <tr><td colspan="6" class="text-muted" style="text-align:center;padding:1rem;">No batteries found. <a href="{{ url_for('battery_add') }}">Add some.</a></td></tr>
-        <tr><td colspan="5" class="text-muted" style="text-align:center;padding:1rem;">No batteries found. <a href="{{ url_for('battery_add') }}">Add one.</a></td></tr>
+          {% endfor %}
-        {% endfor %}
+        </tbody>
-      </tbody>
+      </table>
-    </table>
+    </div>
-  </div>
+
+  </form>
 </div>
+
+<script>
+(function () {
+  var cbs = document.querySelectorAll('.row-cb');
+  var selectAll = document.getElementById('select-all');
+  var toolbar = document.getElementById('bulk-toolbar');
+  var countEl = document.getElementById('selected-count');
+
+  function updateToolbar() {
+    var checked = document.querySelectorAll('.row-cb:checked');
+    var n = checked.length;
+    toolbar.style.display = n > 0 ? 'flex' : 'none';
+    countEl.textContent = n + ' selected';
+    selectAll.indeterminate = n > 0 && n < cbs.length;
+    selectAll.checked = cbs.length > 0 && n === cbs.length;
+  }
+
+  cbs.forEach(function (cb) { cb.addEventListener('change', updateToolbar); });
+  selectAll.addEventListener('change', function () {
+    cbs.forEach(function (cb) { cb.checked = selectAll.checked; });
+    updateToolbar();
+  });
+}());
+</script>
 {% endblock %}

templates/device_detail.html

@@ -25,6 +25,24 @@
   </table>
 </div>
 
+<div class="card">
+  <h2>Install Batteries</h2>
+  {% set free_slots = device.battery_slots - device.installed_count() %}
+  <p class="text-muted" style="margin-bottom:0.75rem;">{{ free_slots }} slot(s) free</p>
+  <form method="post" action="{{ url_for('device_install', device_id=device.id) }}">
+    <div style="display:grid;grid-template-columns:1fr auto;gap:0.4rem;max-width:360px;align-items:center;margin-bottom:0.75rem;">
+      <span style="font-weight:600;font-size:0.85rem;color:#64748b;">Brand</span>
+      <span style="font-weight:600;font-size:0.85rem;color:#64748b;">Qty</span>
+      {% for _ in range(4) %}
+      <input type="text" name="brand[]" placeholder="e.g. Eneloop" style="padding:0.3rem 0.5rem;">
+      <input type="number" name="qty[]" value="0" min="0"
+             style="padding:0.3rem 0.5rem;width:4rem;text-align:center;">
+      {% endfor %}
+    </div>
+    <button class="btn btn-primary" type="submit">Install</button>
+  </form>
+</div>
+
 <div class="card">
   <h2>Installed Batteries</h2>
   {% set installed = device.batteries | selectattr('status', 'eq', 'installed') | list %}

tests/conftest.py

@@ -31,11 +31,18 @@ def client(app):
 
 @pytest.fixture()
 def seeded_client(app):
-    """Test client pre-loaded with 2 devices and 3 batteries (2 available, 1 retired)."""
+    """Test client pre-loaded with 2 devices and 3 batteries (2 available, 1 retired).
+
+    Batteries:
+      id=1  BrandX 001  (BrandX, available)
+      id=2  BrandY 001  (BrandY, available)
+      id=3  BrandX 002  (BrandX, retired)
+    """
     with app.test_client() as c:
         c.post("/device/add", data={"name": "Device A", "battery_slots": "2"})
         c.post("/device/add", data={"name": "Device B", "battery_slots": "1"})
-        c.post("/battery/add", data={"label": "TST-01", "brand": "BrandX", "status": "available"})
+        c.post("/battery/add", data={"brand": "BrandX", "count": "1"})  # id=1
-        c.post("/battery/add", data={"label": "TST-02", "brand": "BrandY", "status": "available"})
+        c.post("/battery/add", data={"brand": "BrandY", "count": "1"})  # id=2
-        c.post("/battery/add", data={"label": "TST-03", "brand": "BrandX", "status": "retired"})
+        c.post("/battery/add", data={"brand": "BrandX", "count": "1"})  # id=3
+        c.post("/battery/3/retire")
         yield c

tests/test_acceptance.py

@@ -4,7 +4,8 @@ Acceptance tests for Battery Tracker.
 Each test gets a fresh in-memory SQLite database via the fixtures in conftest.py.
 The `seeded_client` fixture pre-populates:
   Devices:   Device A (2 slots), Device B (1 slot)
-  Batteries: TST-01 (BrandX, available), TST-02 (BrandY, available), TST-03 (BrandX, retired)
+  Batteries: BrandX 001 (id=1, available), BrandY 001 (id=2, available),
+             BrandX 002 (id=3, retired)
 """
 
 import pytest
@@ -17,7 +18,6 @@ import pytest
 def get_location(resp):
     """Return the redirect Location header (without host)."""
     loc = resp.headers.get("Location", "")
-    # Strip scheme+host if present
     if loc.startswith("http"):
         from urllib.parse import urlparse
         loc = urlparse(loc).path
@@ -36,34 +36,37 @@ def follow(client, resp):
 def test_dashboard_loads(seeded_client):
     resp = seeded_client.get("/")
     assert resp.status_code == 200
-    assert b"TST-01" in resp.data
+    assert b"BrandX 001" in resp.data
-    assert b"TST-02" in resp.data
+    assert b"BrandY 001" in resp.data
-    assert b"TST-03" in resp.data
+    assert b"BrandX 002" in resp.data
 
 
 # ------------------------------------------------------------------ #
-# Battery — add
+# Battery — bulk add
 # ------------------------------------------------------------------ #
 
-def test_add_battery(client):
+def test_bulk_add_batteries(client):
     resp = client.post("/battery/add",
-                       data={"label": "NEW-01", "brand": "TestBrand", "status": "available"},
+                       data={"brand": "Eneloop", "count": "3"},
                        follow_redirects=True)
     assert resp.status_code == 200
-    assert b"NEW-01" in resp.data
+    assert b"Eneloop 001" in resp.data
+    assert b"Eneloop 002" in resp.data
+    assert b"Eneloop 003" in resp.data
 
 
-def test_add_battery_duplicate_label(seeded_client):
+def test_bulk_add_autogenerates_sequential_labels(client):
-    resp = seeded_client.post("/battery/add",
+    client.post("/battery/add", data={"brand": "Eneloop", "count": "2"})
-                              data={"label": "TST-01", "brand": "OtherBrand", "status": "available"})
+    resp = client.post("/battery/add", data={"brand": "Eneloop", "count": "2"},
+                       follow_redirects=True)
+    assert b"Eneloop 003" in resp.data
+    assert b"Eneloop 004" in resp.data
+
+
+def test_bulk_add_missing_brand(client):
+    resp = client.post("/battery/add", data={"brand": "", "count": "1"})
     assert resp.status_code == 400
-    assert b"already exists" in resp.data
+    assert b"required" in resp.data.lower()
-
-
-def test_add_battery_missing_fields(client):
-    resp = client.post("/battery/add", data={"label": "", "brand": ""})
-    assert resp.status_code == 400
-    assert b"required" in resp.data
 
 
 # ------------------------------------------------------------------ #
@@ -73,7 +76,7 @@ def test_add_battery_missing_fields(client):
 def test_battery_detail(seeded_client):
     resp = seeded_client.get("/battery/1")
     assert resp.status_code == 200
-    assert b"TST-01" in resp.data
+    assert b"BrandX 001" in resp.data
     assert b"BrandX" in resp.data
 
 
@@ -93,11 +96,10 @@ def test_edit_notes(seeded_client):
 
 
 # ------------------------------------------------------------------ #
-# Battery — assign
+# Battery — assign (per-battery, kept for special cases)
 # ------------------------------------------------------------------ #
 
 def test_assign_battery(seeded_client):
-    # TST-01 is battery id=1, Device A is device id=1
     resp = seeded_client.post("/battery/1/assign",
                               data={"device_id": "1"},
                               follow_redirects=True)
@@ -106,7 +108,7 @@ def test_assign_battery(seeded_client):
 
 
 def test_assign_retired_battery_blocked(seeded_client):
-    # TST-03 is retired (id=3)
+    # id=3 is retired
     resp = seeded_client.post("/battery/3/assign",
                               data={"device_id": "1"},
                               follow_redirects=True)
@@ -115,9 +117,9 @@ def test_assign_retired_battery_blocked(seeded_client):
 
 
 def test_assign_over_capacity_blocked(seeded_client):
-    # Fill Device B (1 slot) with TST-01
+    # Fill Device B (1 slot) with id=1
     seeded_client.post("/battery/1/assign", data={"device_id": "2"})
-    # Try to assign TST-02 to the same full device
+    # Try to assign id=2 to the same full device
     resp = seeded_client.post("/battery/2/assign",
                               data={"device_id": "2"},
                               follow_redirects=True)
@@ -126,14 +128,13 @@ def test_assign_over_capacity_blocked(seeded_client):
 
 
 def test_brand_mix_warning(seeded_client):
-    # Assign TST-01 (BrandX) to Device A
+    # Assign BrandX 001 (id=1) to Device A
     seeded_client.post("/battery/1/assign", data={"device_id": "1"})
-    # Assign TST-02 (BrandY) to same Device A → brand mix warning, but succeeds
+    # Assign BrandY 001 (id=2) to same Device A → brand mix warning, but succeeds
     resp = seeded_client.post("/battery/2/assign",
                               data={"device_id": "1"},
                               follow_redirects=True)
     assert resp.status_code == 200
-    # Warning flash should mention mixing
     assert b"mixing" in resp.data.lower() or b"mix" in resp.data.lower() or b"brand" in resp.data.lower()
 
 
@@ -145,7 +146,6 @@ def test_unassign_battery(seeded_client):
     seeded_client.post("/battery/1/assign", data={"device_id": "1"})
     resp = seeded_client.post("/battery/1/unassign", follow_redirects=True)
     assert resp.status_code == 200
-    # Battery should show as available on dashboard
     resp2 = seeded_client.get("/battery/1")
     assert b"available" in resp2.data.lower()
 
@@ -169,7 +169,7 @@ def test_retire_clears_device(seeded_client):
 
 
 def test_retire_already_retired(seeded_client):
-    # TST-03 is already retired (id=3)
+    # id=3 is already retired by fixture
     resp = seeded_client.post("/battery/3/retire", follow_redirects=True)
     assert resp.status_code == 200
     assert b"already retired" in resp.data.lower()
@@ -183,7 +183,7 @@ def test_delete_battery_confirmation_page(seeded_client):
     resp = seeded_client.get("/battery/1/delete")
     assert resp.status_code == 200
     assert b"Confirm Delete" in resp.data
-    assert b"TST-01" in resp.data
+    assert b"BrandX 001" in resp.data
 
 
 def test_delete_battery(seeded_client):
@@ -192,6 +192,108 @@ def test_delete_battery(seeded_client):
     assert resp.status_code == 404
 
 
+# ------------------------------------------------------------------ #
+# Battery — bulk actions
+# ------------------------------------------------------------------ #
+
+def test_bulk_retire(client):
+    client.post("/battery/add", data={"brand": "TestBrand", "count": "2"})
+    resp = client.post("/battery/bulk-action",
+                       data={"battery_ids": ["1", "2"], "action": "retire"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"retired" in client.get("/battery/1").data.lower()
+    assert b"retired" in client.get("/battery/2").data.lower()
+
+
+def test_bulk_delete(client):
+    client.post("/battery/add", data={"brand": "TestBrand", "count": "2"})
+    resp = client.post("/battery/bulk-action",
+                       data={"battery_ids": ["1", "2"], "action": "delete"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert client.get("/battery/1").status_code == 404
+    assert client.get("/battery/2").status_code == 404
+
+
+def test_bulk_unassign(client):
+    client.post("/device/add", data={"name": "Gadget", "battery_slots": "2"})
+    client.post("/battery/add", data={"brand": "TestBrand", "count": "2"})
+    client.post("/device/1/install", data={"brand[]": "TestBrand", "qty[]": "2"})
+    resp = client.post("/battery/bulk-action",
+                       data={"battery_ids": ["1", "2"], "action": "unassign"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"available" in client.get("/battery/1").data.lower()
+
+
+def test_bulk_set_brand(client):
+    client.post("/battery/add", data={"brand": "OldBrand", "count": "2"})
+    resp = client.post("/battery/bulk-action",
+                       data={"battery_ids": ["1", "2"], "action": "set_brand",
+                             "new_brand": "NewBrand"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"NewBrand" in client.get("/battery/1").data
+
+
+def test_bulk_action_no_selection(client):
+    client.post("/battery/add", data={"brand": "TestBrand", "count": "1"})
+    resp = client.post("/battery/bulk-action",
+                       data={"action": "retire"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"No batteries selected" in resp.data
+
+
+# ------------------------------------------------------------------ #
+# Device — install batteries
+# ------------------------------------------------------------------ #
+
+def test_device_install_autoselects(client):
+    client.post("/device/add", data={"name": "Gadget", "battery_slots": "2"})
+    client.post("/battery/add", data={"brand": "Eneloop", "count": "3"})
+    resp = client.post("/device/1/install",
+                       data={"brand[]": "Eneloop", "qty[]": "2"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    # Device detail should show 2 installed batteries
+    assert b"Eneloop" in resp.data
+    assert b"2 / 2" in resp.data
+
+
+def test_device_install_mixed_brands(client):
+    client.post("/device/add", data={"name": "Remote", "battery_slots": "4"})
+    client.post("/battery/add", data={"brand": "Eneloop", "count": "2"})
+    client.post("/battery/add", data={"brand": "Energizer", "count": "2"})
+    resp = client.post("/device/1/install",
+                       data={"brand[]": ["Eneloop", "Energizer"], "qty[]": ["2", "2"]},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"Eneloop" in resp.data
+    assert b"Energizer" in resp.data
+
+
+def test_device_install_insufficient_batteries(client):
+    client.post("/device/add", data={"name": "Gadget", "battery_slots": "4"})
+    client.post("/battery/add", data={"brand": "Eneloop", "count": "1"})
+    resp = client.post("/device/1/install",
+                       data={"brand[]": "Eneloop", "qty[]": "2"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"available" in resp.data.lower()
+
+
+def test_device_install_over_capacity(client):
+    client.post("/device/add", data={"name": "Gadget", "battery_slots": "1"})
+    client.post("/battery/add", data={"brand": "Eneloop", "count": "3"})
+    resp = client.post("/device/1/install",
+                       data={"brand[]": "Eneloop", "qty[]": "3"},
+                       follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"slot" in resp.data.lower()
+
+
 # ------------------------------------------------------------------ #
 # Device — list
 # ------------------------------------------------------------------ #
@@ -248,12 +350,9 @@ def test_device_detail_not_found(client):
 # ------------------------------------------------------------------ #
 
 def test_delete_device_frees_batteries(seeded_client):
-    # Assign TST-01 to Device A
     seeded_client.post("/battery/1/assign", data={"device_id": "1"})
-    # Delete Device A
     resp = seeded_client.post("/device/1/delete", follow_redirects=True)
     assert resp.status_code == 200
-    # TST-01 should now be available
     resp2 = seeded_client.get("/battery/1")
     assert b"available" in resp2.data.lower()
 
@@ -268,14 +367,12 @@ def test_delete_device_removed(seeded_client):
 # Full round-trip
 # ------------------------------------------------------------------ #
 
-def test_add_assign_delete_battery(client):
+def test_add_install_delete_battery(client):
-    # Add a device
     client.post("/device/add", data={"name": "Gadget", "battery_slots": "1"})
-    # Add a battery
+    client.post("/battery/add", data={"brand": "AcmeBrand", "count": "1"})
-    client.post("/battery/add", data={"label": "RT-01", "brand": "AcmeBrand", "status": "available"})
+    resp = client.post("/device/1/install",
-    # Assign it
+                       data={"brand[]": "AcmeBrand", "qty[]": "1"},
-    resp = client.post("/battery/1/assign", data={"device_id": "1"}, follow_redirects=True)
+                       follow_redirects=True)
     assert b"Gadget" in resp.data
-    # Delete it
     client.post("/battery/1/delete")
     assert client.get("/battery/1").status_code == 404