Three features: device dropdown filter, charge log history, unassign-all

- Device dropdowns (quick-assign, bulk install, assign page) now only show
  devices with free slots; full devices are excluded entirely
- New ChargeLog model tracks charge dates with optional cycle increment;
  battery detail page gets a Charge History card with add/delete rows
- Device list page gets per-device Unassign All button (with confirmation)
  via new POST /device/<id>/unassign-all route

app.py

@@ -2,7 +2,7 @@ from flask import Flask, render_template, redirect, url_for, request, flash, abo
 from sqlalchemy import create_engine, func
 from sqlalchemy.orm import scoped_session, sessionmaker
 
-from models import Base, Battery, Device, CapacityTest
+from models import Base, Battery, Device, CapacityTest, ChargeLog
 
 
 def create_app(config_object="config"):
@@ -39,8 +39,10 @@ def create_app(config_object="config"):
             .distinct().order_by(Battery.storage_location).all()
         ]
         devices = db.query(Device).order_by(Device.name).all()
+        devices_with_slots = [d for d in devices if d.installed_count() < d.battery_slots]
         return render_template("dashboard.html", batteries=batteries,
-                               storage_locations=storage_locations, devices=devices)
+                               storage_locations=storage_locations, devices=devices,
+                               devices_with_slots=devices_with_slots)
 
     # ------------------------------------------------------------------ #
     # Battery — add
@@ -114,9 +116,14 @@ def create_app(config_object="config"):
                           .filter_by(battery_id=battery_id)
                           .order_by(CapacityTest.tested_date, CapacityTest.id)
                           .all())
+        charge_logs = (db.query(ChargeLog)
+                       .filter_by(battery_id=battery_id)
+                       .order_by(ChargeLog.charged_date.desc(), ChargeLog.id.desc())
+                       .all())
         return render_template("battery_detail.html", battery=battery,
                                storage_locations=storage_locations,
-                               capacity_tests=capacity_tests)
+                               capacity_tests=capacity_tests,
+                               charge_logs=charge_logs)
 
     # ------------------------------------------------------------------ #
     # Battery — edit notes
@@ -199,6 +206,42 @@ def create_app(config_object="config"):
         flash("Test record deleted.", "success")
         return redirect(url_for("battery_detail", battery_id=battery_id))
 
+    # ------------------------------------------------------------------ #
+    # Battery — charge log history
+    # ------------------------------------------------------------------ #
+
+    @app.route("/battery/<int:battery_id>/charge-log/add", methods=["POST"])
+    def battery_charge_log_add(battery_id):
+        battery = db.get(Battery, battery_id)
+        if battery is None:
+            abort(404)
+        date_val = request.form.get("charged_date", "").strip()
+        if not date_val:
+            flash("Date is required.", "error")
+            return redirect(url_for("battery_detail", battery_id=battery_id))
+        increment = 1 if request.form.get("increment_cycles") else 0
+        notes = request.form.get("notes", "").strip() or None
+        if increment:
+            battery.charge_cycles = (battery.charge_cycles or 0) + 1
+        db.add(ChargeLog(battery_id=battery_id, charged_date=date_val,
+                         increment_cycles=increment, notes=notes))
+        db.commit()
+        flash("Charge log entry added.", "success")
+        return redirect(url_for("battery_detail", battery_id=battery_id))
+
+    @app.route("/battery/<int:battery_id>/charge-log/<int:log_id>/delete", methods=["POST"])
+    def battery_charge_log_delete(battery_id, log_id):
+        battery = db.get(Battery, battery_id)
+        log = db.get(ChargeLog, log_id)
+        if battery is None or log is None or log.battery_id != battery_id:
+            abort(404)
+        if log.increment_cycles:
+            battery.charge_cycles = max(0, (battery.charge_cycles or 0) - 1)
+        db.delete(log)
+        db.commit()
+        flash("Charge log entry deleted.", "success")
+        return redirect(url_for("battery_detail", battery_id=battery_id))
+
     # ------------------------------------------------------------------ #
     # Battery — assign
     # ------------------------------------------------------------------ #
@@ -214,13 +257,14 @@ def create_app(config_object="config"):
             return redirect(url_for("battery_detail", battery_id=battery_id))
 
         devices = db.query(Device).order_by(Device.name).all()
+        devices_with_slots = [d for d in devices if d.installed_count() < d.battery_slots]
 
         if request.method == "POST":
             device_id = request.form.get("device_id", type=int)
             device = db.get(Device, device_id)
             if device is None:
                 flash("Device not found.", "error")
-                return render_template("assign.html", battery=battery, devices=devices)
+                return render_template("assign.html", battery=battery, devices=devices_with_slots)
 
             if device.installed_count() >= device.battery_slots:
                 flash(
@@ -228,7 +272,7 @@ def create_app(config_object="config"):
                     f"({device.battery_slots}/{device.battery_slots} slots used).",
                     "error",
                 )
-                return render_template("assign.html", battery=battery, devices=devices)
+                return render_template("assign.html", battery=battery, devices=devices_with_slots)
 
             # Warn on brand mix (non-blocking)
             existing_brands = device.installed_brands()
@@ -249,7 +293,7 @@ def create_app(config_object="config"):
             flash(f"{battery.label} assigned to {device.name}.", "success")
             return redirect(url_for("dashboard"))
 
-        return render_template("assign.html", battery=battery, devices=devices)
+        return render_template("assign.html", battery=battery, devices=devices_with_slots)
 
     # ------------------------------------------------------------------ #
     # Battery — unassign
@@ -668,6 +712,28 @@ def create_app(config_object="config"):
         flash(f"Device '{name}' deleted. All batteries marked available.", "success")
         return redirect(url_for("device_list"))
 
+    # ------------------------------------------------------------------ #
+    # Devices — unassign all batteries
+    # ------------------------------------------------------------------ #
+
+    @app.route("/device/<int:device_id>/unassign-all", methods=["POST"])
+    def device_unassign_all(device_id):
+        device = db.get(Device, device_id)
+        if device is None:
+            abort(404)
+        count = 0
+        for battery in device.batteries:
+            if battery.status == "installed":
+                battery.status = "available"
+                battery.device_id = None
+                count += 1
+        db.commit()
+        flash(
+            f"Unassigned {count} batter{'y' if count == 1 else 'ies'} from {device.name}.",
+            "success",
+        )
+        return redirect(url_for("device_list"))
+
     return app