Merge release/1.0 (0.15.0 + SAFETY-90) into maint-10-local-start-hour

Conflicts: main.py's maintenance import (base added CHARGE, HOLD; branch added
site_zone) - both kept. DOCS maintenance table: base's longer drain-rate row
kept, start hour row at 19 / local.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

goodwe_controller/app/allocator.py

@@ -354,6 +354,11 @@ def pin_w(b):
     return float(pv) if lo > hi else float(_clamp_int(round(float(pv)), lo, hi))
 
 
+def hi_w(b):
+    """A unit's upper hard limit as `plan()` narrows it to whole W (SAFETY-84)."""
+    return float(_int_envelope(b)[1])
+
+
 def loop_bound(bounds, live=None):
     """OPT-11. `(lo, hi)`: what the units can place when the LOOP decides.
 

goodwe_controller/app/arbiter.py

@@ -76,6 +76,12 @@ from . import allocator
 P_SAFETY = 100        # stopped, inputs missing, shutting down, device limits
 P_MAINTENANCE = 60    # maintenance owns the actuator outright (drain, hold)
 P_PEAK = 50           # capacity-tariff peak shaving - costs real money
+# The order in effect: safety limits and the SAFETY-73 refusal > the peak
+# guard > maintenance > modes > trade > loop. A peak floor above a drain still
+# binds: the `drain` site floor at N>=2 (SAFETY-78), refiled at P_MAINTENANCE
+# at N=1 (SAFETY-83); over a HOLD, `_peak_over_hold()` (SAFETY-86).
+# A cheap-window charge is suspended while the peak guard holds and, at N>=2,
+# sized to the quarter's headroom (SAFETY-84).
 P_MAINT_SHAPE = 40    # maintenance shaping the loop (charge-only)
 # OPT-04. §10.1 priority 3 - price arbitrage. ⚠️ ITS POSITION IS THE SPEC, NOT A
 # preference: P_PEAK (50) is ABOVE it so clause 2 lets the capacity-tariff floor
@@ -190,6 +196,16 @@ CLAIM_SCOPE = {
     # charge against the drain (circulation, refused, 0 W). A site `lo`,
     # never filed at N=1. DECISIONS/SAFETY-78-drain-at-two.md.
     "drain": SCOPE_SITE,
+    # main.py: `Claim.limit("charge", P_MAINT_SHAPE, hi=...)`, SAFETY-84. The
+    # mirror of `drain` for a cheap-window maintenance charge at N>=2: the site
+    # target may not go above what the charging pack's own `hi` asks, or a
+    # sibling would have to give against it. Never filed at N=1.
+    # DECISIONS/SAFETY-84-charge-at-two.md.
+    "charge": SCOPE_SITE,
+    # main.py: `Claim.limit("hold", P_MAINTENANCE, hi=...)`, SAFETY-86. While a
+    # holding pack gives the peak shortfall at N>=2, the site target stays at
+    # the peak floor, what the pin and the others place. Never filed at N=1.
+    "hold": SCOPE_SITE,
 
     # --- UNIT: about one pack, one inverter, one device -------------------
     # main.py: `Claim.limit("device", P_SAFETY, self.dev_min, self.dev_max,
@@ -619,7 +635,7 @@ def site_resolve(claims: list) -> Resolution:
 
 
 def resolve(claims: list, *, units=None, weights=None, live=None,
-            tick=None) -> Resolution:
+            tick=None, reserve=()) -> Resolution:
     """The three stages, in order, over one cycle's claims.
 
     `units` is the site's roster of inverters. Left None it is derived from the
@@ -721,6 +737,13 @@ def resolve(claims: list, *, units=None, weights=None, live=None,
     gate, held = _unit_modes(out, site_claims, bounds, live)
     if callable(weights):
         weights = weights(out.target_w)
+    # SAFETY-87/91: units under their peak reserve weigh 0 while the site
+    # gives, so the others carry the target first. An Off battery gives the
+    # peak's shortfall, so it goes before them when no other unit is left.
+    reserve = set(reserve) if out.target_w > 0.0 else set()
+    if held and reserve and not set(bounds) - held - reserve:
+        held = set()
+    held = held | reserve
     if held:
         weights = {u: (0.0 if u in held else
                        (1.0 if weights is None else weights.get(u, 1.0)))

goodwe_controller/app/clamp.py

@@ -260,6 +260,22 @@ def loop_clamp_note(d) -> str:
     return ""
 
 
+def shortfall_note(named) -> str:
+    """SAFETY-85: the alarm text while another owner sets the batteries.
+    `named` is `[(inverter name or None, asked W, given W)]`, one per battery
+    that gave less than asked."""
+    return f"{REASON_CODE}: " + ", ".join(
+        f"{name or 'the battery'} gives {given:+.0f} W of the {asked:+.0f} W "
+        f"asked" for name, asked, given in named)
+
+
+def delivery_short(asked_w, given_w, margin_w) -> bool:
+    """SAFETY-85: did a battery asked to discharge give more than `margin_w`
+    less? A charge is never short: a full pack tapers (SAFETY-42 section 7)."""
+    asked, given = float(asked_w), float(given_w)
+    return asked > 0.0 and asked - given > abs(float(margin_w))
+
+
 def write_clamp_note(named) -> str:
     """The write-side alarm text: `named` is `[(inverter name or None,
     ClampResult)]` for every inverter whose write was cut back this cycle.
@@ -382,6 +398,10 @@ class ClampWatchdog:
         self.over_rating = 0      # bug=True: "Power request too high"
         self.bound = 0            # bug=False: "Battery is not keeping up"
         self.episodes = 0         # rising edges
+        # SAFETY-85: episodes with a bug=False engagement. The status row
+        # counts these; counting cycles read 861 on one rig run.
+        self.bound_episodes = 0
+        self._bound_counted = False
         self.since: datetime | None = None
         self.last_alarm: datetime | None = None
         self.reason = ""
@@ -436,6 +456,10 @@ class ClampWatchdog:
                 self.spoken = False
                 self.bug = False
                 self.bug_spoken = False
+                self._bound_counted = False
+            if not bug and not self._bound_counted:
+                self._bound_counted = True
+                self.bound_episodes += 1
             if bug or not self.bug:
                 self.reason = reason
                 self.facts = tuple(facts)

goodwe_controller/app/control.py

@@ -382,6 +382,9 @@ class Decision:
     # SAFETY-52. The refused direction to carry back in (+1 discharge, -1
     # charge, 0 none), or None when the caller does not carry it.
     refused: int | None = None
+    # SAFETY-85. The `bound` held the integrator or the command this cycle,
+    # so the batteries' limits, not the loop, decided it.
+    held: bool = False
 
 
 def slew_limit_w(tuning: Tuning) -> float:
@@ -481,6 +484,8 @@ def compute(
     refused: int | None = None,
     probe: bool = False,
     bound: tuple | None = None,
+    gave_nothing: bool | None = None,
+    idle_w: float = 0.0,
 ) -> Decision:
     """One control cycle. A cycle is one meter update (~5 s on a HomeWizard P1).
 
@@ -494,6 +499,13 @@ def compute(
     `bound`    OPT-11: `(lo, hi)`, what the batteries may place this tick with
                their modes applied (`allocator.loop_bound()`), or None. See
                MODE_BOUND below. None is the law as it was.
+    `gave_nothing` SAFETY-94: the caller's span check - the reading stayed
+               under REFUSED_BELOW_W, one way, for SETTLE_CYCLES spanning
+               REFUSED_SPAN_S. A refusal engages only with it. None leaves it
+               out (compute() alone, as before).
+    `idle_w`   SAFETY-97: what `actual_w` reads while the batteries give
+               nothing (app/idle.py). The refusal's band and its end are
+               centred on it. 0 is the law as it was.
     """
     reason = "tracking"
     # OPT-11: a bound that leaves out 0 W would FORCE a direction, which no
@@ -614,11 +626,13 @@ def compute(
     # OPT-11: the integrator does not wind past what the modes let the
     # batteries place. Only a side tighter than the rail is left in `bound`
     # (above), so this never takes SAFETY-03's `i_clamped` away from the rail.
+    held_by_bound = False
     if bound is not None:
         held = max(float(bound[0]), min(float(bound[1]), i_w))
         if held != i_w:
             i_w = held
             reason = MODE_BOUND
+            held_by_bound = True
 
     # ⚠️ Applied EVERY cycle, frozen or not: the freeze is conditional, this
     # bound is not. It is what makes the worst-case unwind time finite and
@@ -812,13 +826,18 @@ def compute(
     # `saturation_w` is a refusal, not a slow plant. The drop to 0 skips the slew
     # limit because it only removes an ask the battery is not meeting.
     if refused is not None:
+        # SAFETY-94: and only when the reading has given nothing for the
+        # whole span, not just now. `sat_count` also counts the cycles a
+        # healthy battery spends reversing through its lag (-2000 W towards
+        # +800 W): at a 1 s meter its 12 cycles end as the reading passes 0.
         if (refused == 0 and frozen and sat_count >= SETTLE_CYCLES
                 and abs(prev_w) > tuning.saturation_w
-                and abs(actual_w) < REFUSED_BELOW_W):
+                and abs(actual_w - idle_w) < REFUSED_BELOW_W
+                and gave_nothing is not False):
             refused = 1 if prev_w > 0 else -1
         if refused and refused * i_w < 0:
             refused = 0                          # the loop wants the other way
-        elif refused and refused * actual_w >= PROBE_ANSWER_W:
+        elif refused and refused * (actual_w - idle_w) >= PROBE_ANSWER_W:
             refused = 0                          # it delivers: a probe answered,
             #                                     or a slow reading arriving
         elif refused:
@@ -839,6 +858,7 @@ def compute(
         if inside != target:
             target = inside
             reason = MODE_BOUND
+            held_by_bound = True
         # SAFETY-48's lead cap above may pull the integrator back toward the
         # slewed command; what is CARRIED stays inside the bound too.
         i_w = max(float(bound[0]), min(float(bound[1]), i_w))
@@ -860,7 +880,7 @@ def compute(
 
     return Decision(float(target), sat_count, frozen, reason, float(i_w),
                     i_clamped, clamped, float(i_bound_w), float(want),
-                    float(clamped_w), refused)
+                    float(clamped_w), refused, held_by_bound)
 
 
 def maintenance_charge_floor(

goodwe_controller/app/dayplan.py

@@ -0,0 +1,262 @@
+"""OPT-11 P4: the day plan. Will the sun fill each battery before the
+expensive hours? If not, how much should it take from the grid?
+
+Pure: the forecast (`solarfc`), the house profile, the price runs and the
+batteries in; a level per battery (`Plan.targets`) out. `modetrade.charge_to()`
+turns the level into permission to charge from the grid; main.py rebuilds the
+plan with the price runs (at most every 15 minutes) and keeps a level unless
+it moves by `HYST_KWH` or `HYST_FRAC` (`hold()`).
+
+The sums (OPT-11-design section 1, "Excess solar", with the owner's answers):
+* `sun`: trust x the solar the house will not use, between now and the
+  expensive run the cheap run is for, x the charge efficiency:
+  `trust x sum_h max(0, forecast_h - house_h) x EFF`.
+* Solar first batteries take it first, up to the ceiling. What is left is
+  shared by the Leftover solar batteries by their room.
+* Cheap hours only ignores the plan and fills to the ceiling, as in P3 and
+  the design (section 1). Skipping the sun's share cost money in the replay
+  (PR #156 review: 29.72 against 29.41 EUR on real 2026 prices).
+* A Leftover solar battery charges only up to what the house will draw from
+  it in the expensive runs before the next cheap run, less its share:
+  `min(ceiling, floor + house use / EFF) - share`. So it buys only the
+  shortfall, not up to the ceiling.
+* Solar first never charges from the grid (owner, 2026-09-29).
+
+The house profile is the add-on's own measurement, grid + battery power, per
+local hour, over the last `PROFILE_DAYS` days; the estimate for an hour is the
+median of that hour. It is net of the solar the house used itself, so for
+the solar sum it is never taken below the night-time median (`base()`).
+The site's own solar readings are not used: TEL-11 keeps them out of every
+control decision.
+"""
+
+import statistics
+from dataclasses import dataclass
+from datetime import datetime, timedelta, timezone
+
+from .packmode import LEFTOVER_SOLAR, SOLAR_FIRST
+from .tariff import BILLING_TZ
+
+EFF = 0.95                  # charge (and discharge) efficiency
+HYST_KWH = 1.0              # a kept level moves only by this much...
+HYST_FRAC = 0.10            # ...or this share of the battery's shortfall
+PROFILE_DAYS = 7
+MIN_HOURS = 20              # hours of a day recorded before it counts
+NIGHT_HOURS = (0, 1, 2, 3, 4, 5, 22, 23)
+DEFAULT_TRUST_PCT = 70
+
+# Site verdicts (the page's forecast line).
+SUNNY, PARTLY, DARK = "sunny", "partly", "dark"
+
+
+# --------------------------------------------------------------------------- #
+# The house profile
+# --------------------------------------------------------------------------- #
+def _local(t: datetime):
+    return t.astimezone(BILLING_TZ)
+
+
+class HouseProfile:
+    """Hourly means of the house's net use (grid + battery power), kept per
+    local day and hour: `{"YYYY-MM-DD": {hour: [mean_w, samples]}}`. The
+    store holds `dump()`; `load()` takes it back and drops what is bad."""
+
+    def __init__(self, data=None):
+        self.days = {}
+        self._cur = None            # (day, hour, sum, n)
+        if isinstance(data, dict):
+            self.load(data)
+
+    def load(self, data):
+        for day, hours in data.items():
+            try:
+                datetime.strptime(str(day), "%Y-%m-%d")
+            except ValueError:
+                continue
+            if not isinstance(hours, dict):
+                continue
+            row = {}
+            for h, v in hours.items():
+                try:
+                    hi, w = int(h), float(v)
+                except (TypeError, ValueError):
+                    continue
+                if 0 <= hi < 24 and abs(w) < 1e6:
+                    row[hi] = w
+            if row:
+                self.days[str(day)] = row
+
+    def dump(self) -> dict:
+        return {d: {str(h): round(w, 1) for h, w in sorted(r.items())}
+                for d, r in sorted(self.days.items())}
+
+    def add(self, now: datetime, house_w) -> bool:
+        """One reading. Returns True when an hour closed (then store it)."""
+        lt = _local(now)
+        key = (lt.strftime("%Y-%m-%d"), lt.hour)
+        closed = False
+        if self._cur is not None and self._cur[:2] != key:
+            day, hour, s, n = self._cur
+            if n >= 60:                 # about 5 minutes of readings
+                self.days.setdefault(day, {})[hour] = s / n
+                closed = True
+            self._cur = None
+            self._prune(lt)
+        if house_w is None:
+            return closed
+        if self._cur is None:
+            self._cur = (key[0], key[1], 0.0, 0)
+        d, h, s, n = self._cur
+        self._cur = (d, h, s + float(house_w), n + 1)
+        return closed
+
+    def _prune(self, lt):
+        """Keep the last `PROFILE_DAYS` days; a day after today (the clock
+        was wrong once) would never age out, so it goes too."""
+        keep = (lt.date() - timedelta(days=PROFILE_DAYS)).isoformat()
+        today = lt.date().isoformat()
+        for d in [d for d in self.days if d < keep or d > today]:
+            del self.days[d]
+
+    def ready(self) -> bool:
+        """At least one day with `MIN_HOURS` hours recorded."""
+        return any(len(r) >= MIN_HOURS for r in self.days.values())
+
+    def hour_w(self, hour: int):
+        vals = [r[hour] for r in self.days.values() if hour in r]
+        return statistics.median(vals) if vals else None
+
+    def base(self):
+        vals = [w for h in NIGHT_HOURS if (w := self.hour_w(h)) is not None]
+        return statistics.median(vals) if vals else None
+
+    def estimator(self):
+        """`f(hour) -> W`, or None when not ready. Fixed at call time."""
+        if not self.ready():
+            return None
+        base = self.base() or 0.0
+        table = {}
+        for h in range(24):
+            w = self.hour_w(h)
+            table[h] = base if w is None else w
+        return lambda h: table[h], max(0.0, base)
+
+
+# --------------------------------------------------------------------------- #
+# The plan
+# --------------------------------------------------------------------------- #
+@dataclass(frozen=True)
+class Plan:
+    verdict: str                # SUNNY / PARTLY / DARK
+    sun_kwh: float              # solar the batteries can count on
+    fc_kwh: float               # the forecast over the same span
+    until: datetime             # the expensive run the plan is for
+    targets: dict               # name -> level % (Leftover solar only)
+    need_kwh: dict              # name -> kWh from the grid (0: none)
+    share_kwh: dict             # name -> kWh of solar counted for it
+
+
+def _hour_slices(t0, t1):
+    """Local-hour slices of [t0, t1): (start, end, local hour)."""
+    out, t = [], t0
+    while t < t1:
+        lt = _local(t)
+        nxt = (lt.replace(minute=0, second=0, microsecond=0)
+               + timedelta(hours=1)).astimezone(timezone.utc)
+        e = min(nxt, t1)
+        out.append((t, e, lt.hour))
+        t = e
+    return out
+
+
+def _room(p, to_pct):
+    if p.capacity_kwh is None or p.soc is None:
+        return 0.0
+    return max(0.0, float(to_pct) - float(p.soc)) / 100.0 * float(
+        p.capacity_kwh)
+
+
+def plan(forecast, house, runs, now, packs, *, trust_pct, floor_pct,
+         ceiling_pct):
+    """The day plan, or None when there is none to make: no forecast, no
+    house profile yet, no price plan, or no expensive run after the cheap
+    run. `house` is `HouseProfile.estimator()`'s answer. `packs` are
+    `modetrade.Pack`s."""
+    if forecast is None or house is None or runs is None or not runs.on \
+            or runs.cheap is None:
+        return None
+    house_w, base_w = house
+    until = next((g for g in runs.give if g.start >= runs.cheap.end), None)
+    if until is None:
+        return None
+    trust = max(0.0, min(1.0, float(trust_pct) / 100.0))
+    sun = fc_sum = 0.0
+    for s, e, h in _hour_slices(now, until.start):
+        pv = forecast.between(s, e)
+        if pv is None:
+            return None             # the span reaches a day with no forecast
+        hrs = (e - s).total_seconds() / 3600.0
+        use = max(house_w(h), base_w) * hrs / 1000.0
+        sun += max(0.0, pv - use)
+        fc_sum += pv
+    sun *= trust * EFF
+
+    usable = [p for p in packs if p.use and p.live and p.idle
+              and p.soc is not None and p.capacity_kwh]
+    sf = [p for p in usable if p.mode == SOLAR_FIRST]
+    price = [p for p in usable if p.mode == LEFTOVER_SOLAR]
+    sf_room = sum(_room(p, ceiling_pct) for p in sf)
+    excess = max(0.0, sun - sf_room)
+    rooms = {p.name: _room(p, ceiling_pct) for p in price}
+    total_room = sum(rooms.values())
+
+    # What the house draws in the expensive runs from the one this plan is
+    # for until the next cheap run (or a day), from the profile.
+    horizon = until.start + timedelta(hours=24)
+    use_kwh = 0.0
+    for g in runs.give:
+        if g.start < until.start or g.start >= horizon:
+            continue
+        for s, e, h in _hour_slices(g.start, g.end):
+            use_kwh += max(0.0, house_w(h)) * (
+                e - s).total_seconds() / 3600.0 / 1000.0
+    caps = {p.name: float(p.capacity_kwh) for p in price}
+    cap_sum = sum(caps.values()) or 1.0
+
+    targets, need, share = {}, {}, {}
+    for p in price:
+        sh = excess * rooms[p.name] / total_room if total_room > 0 else 0.0
+        sh_pct = sh / caps[p.name] * 100.0
+        want = use_kwh * caps[p.name] / cap_sum / EFF
+        top = min(float(ceiling_pct),
+                  float(floor_pct) + want / caps[p.name] * 100.0)
+        level = max(0.0, top - sh_pct)
+        targets[p.name] = round(level, 2)
+        need[p.name] = round(_room(p, level), 3)
+        share[p.name] = round(sh, 3)
+    if sun < sf_room:
+        verdict = DARK
+    elif any(v > 0.05 for v in need.values()):
+        verdict = PARTLY
+    else:
+        verdict = SUNNY
+    return Plan(verdict, round(sun, 3), round(fc_sum, 3), until.start,
+                targets, need, share)
+
+
+def hold(old: dict | None, new: dict, capacity: dict) -> dict:
+    """Hysteresis: a battery keeps its old level unless the new one differs
+    by at least `HYST_KWH`, or by `HYST_FRAC` of the larger level's energy
+    (whichever is less). A battery new to the plan takes its level at once;
+    one that left the plan is dropped at once."""
+    out = {}
+    for name, level in new.items():
+        was = (old or {}).get(name)
+        cap = float(capacity.get(name) or 0.0)
+        if was is None or cap <= 0:
+            out[name] = level
+            continue
+        moved = abs(level - was) / 100.0 * cap
+        step = min(HYST_KWH, HYST_FRAC * max(was, level) / 100.0 * cap)
+        out[name] = level if moved >= step else was
+    return out

goodwe_controller/app/freshness.py

@@ -87,6 +87,10 @@ when it has not moved THROUGH A CHANGE IT WAS OBLIGED TO FOLLOW:
                 AND |standing command now - standing command when the reading
                      last changed| >= MOVE_W
 
+SAFETY-94: "unchanged for" counts only the reads at which both command terms
+held, so a register that rested is not judged before it could answer.
+DECISIONS/SAFETY-94-lagging-battery.md.
+
 0x0518 is the inverter reporting ITSELF and it tracks its own command: r = 0.998
 with battery power against r = 0.09 with the real meter (goodwe/NOTES.md §3.3),
 command and actual agreeing within 4 W once settled (§5.10, 2026-08-22), and the
@@ -216,6 +220,8 @@ change - which was the ONLY exit - has a median of 143 s, 17 episodes at or
 over the live one's 710 s, and a worst case of 21440 s. That distribution is a
 property of this battery's firmware. It is not a property of this code, and the
 add-on must not depend on it.
+SAFETY-94: many were the gate judging a rested register on its first read
+(SAFETY-58). Counted from the ask, the same days give 59 trips.
 
 THE RULE, and it is SAFETY-13's shape one module over - "which latches get an
 exit, not how long the block lasts":
@@ -372,7 +378,9 @@ BOUNDS = {
                    "SAFETY-57: the verdict is withdrawn after 17.0 s of the "
                    "standing command below 250 W, because at 0 W the register "
                    "is obliged to nothing and the verdict cannot be tested "
-                   "again from inside the state it creates"),
+                   "again from inside the state it creates. SAFETY-94: the "
+                   "35 s counts only reads at which the command asks the "
+                   "register to move"),
     "soc": Bound(
         signal="soc (0x050E, pack SoC, U16, 1 %, 10 s publish)",
         unchanged_s=float("inf"),
@@ -416,11 +424,9 @@ class Freshness:
     new grading window at that instant. The 1 Hz oscillation the latch exists to
     prevent is still prevented: the new window is `bound.unchanged_s` wide, so
     no re-trip can land sooner than 35 s after a release, rather than on the
-    next read. ⚠️ MEASURED FROM THE RELEASE, NOT FROM THE COMMAND RESUMING - if
-    the site rests for longer than the window before it asks for anything, the
-    window is already old and the re-trip lands on the first read at which the
-    command travels 250 W again. That is survivor 5's shape, it predates this
-    card, and its cost is one `stale_input_s` hold.
+    next read. SAFETY-94: the 35 s counts only while the command asks the
+    register to move, so a site that rests after a release is not re-tripped
+    on its first ask.
 
     ⚠️ TWO CLOCKS, AND THE DISTINCTION IS THE WHOLE OF SAFETY-57'S HONESTY.
     `changed_mono` / `held` are facts about the REGISTER: when it last carried a
@@ -451,6 +457,11 @@ class Freshness:
         # the change-stamps; `_release()` is where they diverge.
         self.graded_from = None
         self.standing_at_grade = None
+        # SAFETY-94. Seconds of this window during which the register was
+        # obliged to move (the command at least `move_w` and `move_w` away
+        # from `standing_at_grade`), and the instant of the last read.
+        self.obliged_acc = 0.0
+        self.last_read = None
         # The instant the standing command last FELL below `move_w`, or None
         # while an obligation is standing. The release timer runs off this.
         self.rested_since = None
@@ -499,6 +510,7 @@ class Freshness:
         # it reads in the order the state machine moves - withdraw, then
         # re-grade - not because the code depends on it.
         self._release(standing_w, now_mono)
+        self._oblige(standing_w, now_mono)
         self._grade(standing_w, now_mono)
 
     def _open_window(self, standing_w, now_mono) -> None:
@@ -510,6 +522,35 @@ class Freshness:
         self.graded_from = float(now_mono)
         self.standing_at_grade = (None if standing_w is None
                                   else float(standing_w))
+        # The read that opens a window is never an ask (no travel yet).
+        self.obliged_acc = 0.0
+
+    def _obliged(self, standing_w) -> bool:
+        """Is the register asked to move: the command is at least `move_w` and
+        has travelled `move_w` since the window opened?"""
+        if standing_w is None or self.standing_at_grade is None:
+            return False
+        standing_w = float(standing_w)
+        return (abs(standing_w) >= self.bound.move_w
+                and abs(standing_w - self.standing_at_grade)
+                >= self.bound.move_w)
+
+    def _oblige(self, standing_w, now_mono) -> None:
+        """SAFETY-94. Count only the time the register was asked to move.
+
+        A register that held still while nothing asked it to move has not
+        failed, so time before the command moved is not evidence. The time
+        since the previous read counts when the obligation stands at this
+        read; a command flapping in and out of the obligation still adds up.
+        """
+        now_mono = float(now_mono)
+        if self.last_read is not None and self._obliged(standing_w):
+            self.obliged_acc += max(0.0, now_mono - self.last_read)
+        self.last_read = now_mono
+
+    def obliged_s(self) -> float:
+        """Seconds of the current window the register was obliged to move."""
+        return self.obliged_acc
 
     def _release(self, standing_w, now_mono) -> None:
         """SAFETY-57. Withdraw a verdict whose obligation is no longer standing.
@@ -543,7 +584,12 @@ class Freshness:
         if self.stale or self.graded_from is None:
             return
         held_s = self.graded_s(now_mono)
-        if held_s < self.bound.unchanged_s:
+        # SAFETY-94 (closes SAFETY-58): the bound counts only the time the
+        # command asked the register to move, not the time since it last
+        # changed. A register that rested for minutes was otherwise judged on
+        # the first read after a new command, before it could answer (live,
+        # 2026-10-03: 1 s after the command).
+        if self.obliged_s() < self.bound.unchanged_s:
             return
         # ⚠️ BOTH None GUARDS ARE FOR A CALLER THAT DOES NOT KNOW ITS OWN
         # OBLIGATION YET, WHICH IS NOT `_read_unit`. `Inverter.standing_w()`

goodwe_controller/app/homeview.py

@@ -345,7 +345,10 @@ def mode_runs(c, day0, day1, now, shadow):
                                    else (soc - floor)) / 100.0 * cap)
             return kwh
         blocks = []
-        if rp.charge_useful() and pm.mode in GRID_CHARGE_MODES:
+        # P4: with a day plan, the grid block is the planned shortfall.
+        need = plan_need(c, inv.name)
+        if rp.charge_useful() and (need > 0.0 if need is not None
+                                   else pm.mode in GRID_CHARGE_MODES):
             blocks.append(("grid", rp.cheap))
         sell = rp.sell if pm.sell and pm.can_sell else None
         for g in rp.give:
@@ -358,6 +361,8 @@ def mode_runs(c, day0, day1, now, shadow):
                 continue
             hrs = (run.end - run.start).total_seconds() / 3600.0
             kwh = room(kind, hrs)
+            if kind == "grid" and need is not None:
+                kwh = min(kwh, need)
             if kwh < MIN_KWH:
                 continue
             price = run.mean_eur_kwh
@@ -382,6 +387,56 @@ def mode_runs(c, day0, day1, now, shadow):
     return out, None
 
 
+def plan_need(c, name):
+    """P4: kWh this battery buys from the grid by the day plan, or None when
+    there is no plan for it (then P3 option A applies)."""
+    targets = c.plan_targets() if hasattr(c, "plan_targets") else None
+    if not targets or name not in targets:
+        return None
+    inv = next((i for i in c.inverters if i.name == name), None)
+    if inv is None or inv.soc is None or not inv.capacity_kwh:
+        return None
+    return max(0.0, targets[name] - float(inv.soc)) / 100.0 * float(
+        inv.capacity_kwh)
+
+
+def plan_state(c):
+    """P4: `"plan"` (a day plan is made), `"learning"` (no house profile
+    yet), `"no_forecast"` (set but missing or stale), or None (not set, or
+    battery modes off)."""
+    if not getattr(c, "modes_on", False) or \
+            getattr(c, "fc_entity", None) is None:
+        return None
+    if getattr(c, "solar_fc", None) is None:
+        return "no_forecast"
+    hp = getattr(c, "house_profile", None)
+    if hp is not None and not hp.ready():
+        return "learning"
+    return "plan" if getattr(c, "day_plan", None) is not None else None
+
+
+def solar_block(c, now):
+    """P4: the solar forecast line for the Batteries screen and the Simple
+    settings view: `{state, fc_kwh, count_kwh, updated, line}`."""
+    st = plan_state(c)
+    out = {"state": st, "fc_kwh": None, "count_kwh": None, "updated": None,
+           "line": ""}
+    if st is None and getattr(c, "solar_fc", None) is None:
+        return out
+    fc = getattr(c, "solar_fc", None)
+    if fc is not None:
+        trust = float(getattr(c, "solar_trust_pct", 70)) / 100.0
+        out.update(fc_kwh=round(fc.today.kwh, 1),
+                   count_kwh=round(fc.today.kwh * trust, 1),
+                   updated=hhmm(fc.at))
+    if st in ("no_forecast", "learning"):
+        out["line"] = _t("solar." + st)
+    elif fc is not None:
+        out["line"] = line_solar(fc.today.kwh, out["count_kwh"],
+                                 out["updated"])
+    return out
+
+
 def maintenance_runs(c, day0, day1, now, shadow):
     """The monthly battery cycle: under way now, or starting later today.
     The cycle starts in the hour `maintenance_start_hour` names, read in the
@@ -663,7 +718,9 @@ def battery_rows(c, shadow, running, held=False):
             refused=refusing(c, inv), peak=peak,
             giving=flow(inv.batt) == "giving", other_refuses=other,
             sf_ahead=sf_ahead, role=role, plan=plan, has_at=bool(at),
-            other_cycle=cycling)
+            other_cycle=cycling,
+            day=None if pm is None or pm.mode not in PRICE_MODES
+            else day_key(c, inv.name))
         rows.append({
             "name": inv.name,
             "level_pct": None if inv.soc is None else float(inv.soc),
@@ -698,10 +755,25 @@ def battery_rows(c, shadow, running, held=False):
     return rows
 
 
+def day_key(c, name):
+    """P4: the day plan's word for one Leftover solar or Cheap hours
+    battery: `sun_fills`, `tops_up`, `no_forecast`, or None."""
+    st = plan_state(c)
+    if st == "no_forecast":
+        mode = c.pack_mode(next(i for i in c.inverters if i.name == name))
+        return "no_forecast" if mode.mode == LEFTOVER_SOLAR else None
+    if st != "plan":
+        return None
+    need = plan_need(c, name)
+    if need is None:
+        return None
+    return "tops_up" if need >= MIN_KWH else "sun_fills"
+
+
 def battery_why(*, modes_on, mode, off, reading, phase, shadow, running,
                 held, refused, peak, sf_ahead, giving=False,
                 other_refuses=None, role=None, plan=None,
-                has_at=False, other_cycle=None) -> str:
+                has_at=False, other_cycle=None, day=None) -> str:
     """The key of one battery's "why" line (`home_words.why`), most urgent
     first. Pure, so every branch is tested without a controller."""
     if not reading:
@@ -728,6 +800,8 @@ def battery_why(*, modes_on, mode, off, reading, phase, shadow, running,
     if not modes_on:
         return "modes_off"
     # OPT-11 P3: the battery's role in the price runs this cycle.
+    if role == "hold" and day is not None:
+        return day              # P4: what the day plan decided
     if role in ROLE_WHY:
         if role == "hold" and not has_at:
             return "saves_later"
@@ -829,7 +903,9 @@ def month_peak(c, now):
     if pg is not None:
         out["period_w"] = pg.projected_w
         ceiling = pg.ceiling_w or limit_w
-    out["line"] = line_period(out["period_w"], ceiling, c.shadow)
+    out["line"] = line_period(out["period_w"], ceiling, c.shadow,
+                              unmeasured=getattr(c, "peak_unmeasured_s", 0.0)
+                              > 0.0)
     return out
 
 
@@ -848,24 +924,25 @@ def state_of(c, level, shadow):
 
 
 def build(c, *, level: str, checks: list, now: datetime | None = None,
-          lang: str = "en") -> dict:
+          lang: str = "en", held: bool | None = None) -> dict:
     """The structured half of `/status`, in `lang` (UX-13 P5). Pure reads of
     the controller."""
     _LANG[0] = uitext.lang_of(lang)
     try:
-        return _build(c, level=level, checks=checks, now=now)
+        return _build(c, level=level, checks=checks, now=now, held=held)
     finally:
         _LANG[0] = "en"
 
 
-def _build(c, *, level, checks, now):
+def _build(c, *, level, checks, now, held=None):
     now = now or datetime.now(timezone.utc)
     shadow = bool(c.shadow)
     kind = state_of(c, level, shadow)
     # A red banner means every inverter is at 0 W (the status cascade), so
     # nothing is planned until it clears. Shadow mode still plans: it is
-    # what the add-on would do.
-    held = level == "bad" and not shadow
+    # what the add-on would do. `held` False: an alarm while control runs
+    # (SAFETY-87, the peak alarms).
+    held = level == "bad" and not shadow and held is not False
     running = (bool(c.auto) or shadow) and not held
     settled = all(at_zero(inv) for inv in c.inverters)
     ctl = next((r for r in checks if r.get("id") == "controller"), None)
@@ -875,6 +952,7 @@ def _build(c, *, level, checks, now):
                  modes_on=bool(getattr(c, "modes_on", False)),
                  running=running, held=held, shadow=shadow)
     return {
+        "solar": solar_block(c, now),
         "state": {"kind": kind, "pill": pill(kind),
                   "ran": ctl.get("text", "") if ctl else "",
                   "sub": banner_sub(kind)},
@@ -1171,6 +1249,10 @@ def run_house_amount() -> str:
     return _t("run.house_amount")
 
 
+def line_solar(fc_kwh, count_kwh, at) -> str:
+    return _t("solar.line", kwh=_kwh(fc_kwh), count=_kwh(count_kwh), at=at)
+
+
 def line_no_trade(key) -> str:
     return "" if key == "off" else _t("no_trade." + key)
 
@@ -1213,8 +1295,11 @@ def line_peak_not_covered() -> str:
     return _t("peak_not_covered")
 
 
-def line_period(period_w, limit_w, shadow) -> str:
+def line_period(period_w, limit_w, shadow, unmeasured=False) -> str:
     step = _w(shadow, "step_in", kw=_kw(limit_w))
+    if unmeasured:
+        # SAFETY-90: the add-on started during this period.
+        return _t("period_unmeasured") + " " + step
     if period_w is None:
         return step
     return _t("period", kw=_kw(period_w)) + " " + step
@@ -1288,6 +1373,7 @@ def _samples() -> list:
                 ("plan", line_peak_limit(3500, sh)),
                 ("plan", line_period(1240, 3500, sh)),
                 ("plan", line_period(None, 3500, sh)),
+                ("plan", line_period(1240, 3500, sh, unmeasured=True)),
                 ("plan", control_text(True, sh)),
                 ("plan", control_text(False, sh))]
     out += [("plan", run_grid_why(0.1412)), ("plan", run_grid_amount(1.23)),
@@ -1313,6 +1399,8 @@ def _samples() -> list:
                                                 off=off, peak=peak)))
     out += [("plan", why_words(k, name="Battery A")) for k in words["why"]]
     out += [("plan", today_words(k)) for k in words["today"]]
+    out += [("plan", line_solar(9.2, 6.4, "10:15")),
+            ("plan", _t("solar.no_forecast")), ("plan", _t("solar.learning"))]
     out += [("plan", line_no_trade(k)) for k in
             ("not_covered", "no_prices", "peak", "not_firm", "not_worth",
              "no_level")]

goodwe_controller/app/idle.py

@@ -0,0 +1,87 @@
+"""SAFETY-97: what a battery's power reading shows while it gives nothing.
+
+B's reading (0x0518) shows -95 to -118 W at idle (standby draw, live
+2026-10-03); A's shows -2 to -4 W. "The battery gives nothing" is graded
+against this idle reading, not against 0 W, or a refusing B never latches.
+DECISIONS/SAFETY-97-idle-offset.md.
+
+Learned per unit, never configured:
+- only while control runs, the unit is not refused, stale or tripped, and
+  its command has been within IDLE_ASK_W for IDLE_QUIET_S (a refusing battery
+  is asked more than that, so it cannot teach its refusal as idle);
+- a reading beyond IDLE_SAMPLE_W is not a sample;
+- first value: the mean of IDLE_FIRST_S of samples; then a slow follow
+  (IDLE_TAU_S);
+- persisted per unit and restored, clamped to IDLE_SAMPLE_W, at start.
+The band is centred on it clamped to IDLE_MAX_W (owner, 2026-10-04). Until
+learned the idle reading is 0 W, the rule as it was.
+"""
+
+import math
+
+IDLE_MAX_W = 75.0       # |idle| used: under the 100 W band, so it keeps 0 W +-25 W
+IDLE_SAMPLE_W = 250.0   # a reading beyond this is not a sample
+IDLE_ASK_W = 50.0       # a command this small counts as "asked ~0"
+IDLE_QUIET_S = 120.0    # 6 lags of 20 s: a 2500 W step has decayed to 6 W
+IDLE_FIRST_S = 120.0    # seconds of samples averaged for the first value
+IDLE_TAU_S = 1800.0     # then follow drift this slowly
+IDLE_SAVE_W = 5.0       # persist when the value moved this far
+IDLE_GAP_S = 10.0       # a longer gap between reads counts as this
+
+
+def _num(v):
+    try:
+        v = float(v)
+    except (TypeError, ValueError):
+        return None
+    return v if math.isfinite(v) else None
+
+
+class IdleReading:
+    """One unit's idle reading. `w` is what "gives nothing" is centred on."""
+
+    def __init__(self, saved=None):
+        v = _num(saved)
+        self.value = (None if v is None
+                      else max(-IDLE_SAMPLE_W, min(IDLE_SAMPLE_W, v)))
+        self.saved = self.value
+        self.quiet_since = None
+        self.last = None
+        self.acc_w = 0.0
+        self.acc_s = 0.0
+
+    @property
+    def w(self) -> float:
+        """The centre used: the learned value clamped to IDLE_MAX_W."""
+        if self.value is None:
+            return 0.0
+        return max(-IDLE_MAX_W, min(IDLE_MAX_W, self.value))
+
+    def observe(self, reading, standing_w, now_mono, may_learn) -> bool:
+        """One read. Returns True when the value should be persisted."""
+        now = float(now_mono)
+        dt = (0.0 if self.last is None
+              else max(0.0, min(IDLE_GAP_S, now - self.last)))
+        self.last = now
+        standing = _num(standing_w)
+        if not may_learn or standing is None or abs(standing) > IDLE_ASK_W:
+            self.quiet_since = None
+            return False
+        if self.quiet_since is None:
+            self.quiet_since = now
+        b = _num(reading)
+        if (now - self.quiet_since < IDLE_QUIET_S or b is None
+                or abs(b) > IDLE_SAMPLE_W or dt <= 0.0):
+            return False
+        if self.value is None:
+            self.acc_w += b * dt
+            self.acc_s += dt
+            if self.acc_s < IDLE_FIRST_S:
+                return False
+            self.value = self.acc_w / self.acc_s
+        else:
+            self.value += (b - self.value) * min(1.0, dt / IDLE_TAU_S)
+        if self.saved is None or abs(self.value - self.saved) >= IDLE_SAVE_W:
+            self.saved = self.value
+            return True
+        return False

goodwe_controller/app/inverter.py

@@ -127,6 +127,7 @@ from . import messages
 # SAFETY-37. The freshness policy, and the ONE place its bounds are written.
 # freshness.py imports nothing from this package, so the direction is one-way.
 from .freshness import BOUNDS, Freshness
+from .idle import IdleReading
 # CFG-03's ONE in-code mirror of config.yaml's SAFETY-24 defaults. Imported
 # rather than retyped: the flat-keys path below needs `bms_soc_floor`'s
 # shipped default and a literal here would be the fourth defaults site that
@@ -321,13 +322,21 @@ class Inverter:
         # take, 0 none), when that refusal or its last probe started, the
         # current probe's start, and the cycles of evidence so far and when
         # they began. Memory only, like SAFETY-52's: stop and start end it.
-        # Used at N>1 only.
+        # The evidence count is also used at N=1 (SAFETY-94); the rest at N>1.
         self.refused = 0
         self.refused_at = None
         self.probe_from = None
         self.ref_count = 0
         self.ref_since = None
         self.ref_sign = 0
+        self.ref_from = None
+        # SAFETY-97: what this unit's reading shows at idle; "gives nothing"
+        # is centred on it. Learned, persisted, restored (app/idle.py).
+        self.idle = IdleReading(data.get(self.key("idle_w")))
+
+    @property
+    def idle_w(self) -> float:
+        return self.idle.w
 
     # -- store ---------------------------------------------------------------
     def key(self, name: str) -> str:

goodwe_controller/app/messages.py

@@ -217,7 +217,7 @@ def peak_saturated(ceiling_w, *, shadow: bool = False) -> Notice:
 
 
 def peak_reserve(ceiling_w, *, soc_unread: bool, floor_unknown: bool,
-                 packs=()) -> Notice:
+                 packs=(), others: bool = False) -> Notice:
     """SAFETY-24/25/32: the peak guard may not draw the battery any lower.
 
     The last sentence is SAFETY-25 and must stay: the reserve binds the peak
@@ -227,7 +227,8 @@ def peak_reserve(ceiling_w, *, soc_unread: bool, floor_unknown: bool,
     roster means some inverter's cut-out level is missing (the peak reserve
     itself always has a value) - so the action names the cut-out level.
     Both are named by their setting labels, "Peak reserve (%)" and "Battery
-    cut-out level (%)".
+    cut-out level (%)". `others`: the other batteries give all they can and
+    it is not enough (SAFETY-87), so the limit MAY be passed.
     """
     if soc_unread:
         why = "The battery level cannot be read"
@@ -241,6 +242,12 @@ def peak_reserve(ceiling_w, *, soc_unread: bool, floor_unknown: bool,
         why = (f"The battery of {names(packs)} is at its peak reserve" if packs
                else "The battery is at its peak reserve")
         act = "Switch off large loads, or lower the peak reserve."
+    if others:
+        return Notice(ID_PEAK_RESERVE, ALARM, T_PEAK_RESERVE,
+                      f"{why}, and the other batteries cannot keep this "
+                      f"15-minute period under your {watts(ceiling_w)} peak "
+                      f"limit alone. {act} Home use can still draw a battery "
+                      f"below its reserve, down to its cut-out level.")
     return Notice(ID_PEAK_RESERVE, ALARM, T_PEAK_RESERVE,
                   f"{why}, so this 15-minute period will go over your "
                   f"{watts(ceiling_w)} peak limit and raise this month's peak. "
@@ -470,8 +477,9 @@ def row_peak_saturated(ceiling_w) -> str:
 
 
 def row_peak_reserve(ceiling_w, *, soc_unread: bool, floor_unknown: bool,
-                     packs=()) -> str:
-    """SAFETY-24/25/32. The second sentence is SAFETY-25 and must stay."""
+                     packs=(), others: bool = False) -> str:
+    """SAFETY-24/25/32. The last sentence is SAFETY-25 and must stay.
+    `others`: as in `peak_reserve()` (SAFETY-87)."""
     if soc_unread:
         why = "Battery level cannot be read"
     elif floor_unknown:
@@ -479,6 +487,10 @@ def row_peak_reserve(ceiling_w, *, soc_unread: bool, floor_unknown: bool,
     else:
         why = (f"{names(packs)} battery at its peak reserve" if packs
                else "Battery at its peak reserve")
+    if others:
+        return (f"{why}. The others cannot hold the {watts(ceiling_w)} peak "
+                f"limit alone. Home use still draws it lower, to the cut-out "
+                f"level.")
     return (f"{why}, so the {watts(ceiling_w)} peak limit will be passed. Home "
             f"use still draws the battery below it, down to the cut-out level.")
 
@@ -781,6 +793,12 @@ def row_peak_guard_blind(why: str) -> str:
             f"meanwhile")
 
 
+def row_peak_guard_unmeasured() -> str:
+    """SAFETY-90. Before the first reading; that part counts as high use."""
+    return ("Peak guard: part of this 15-minute period was not measured, "
+            "counted as high use")
+
+
 def row_peak_guard_on(floor_w, limit_w, *, shadow: bool = False) -> str:
     if shadow:
         return (f"Peak guard: would ask for {watts(floor_w)} to stay under "
@@ -835,6 +853,8 @@ WHY_LIMIT = {
     "pack": "the battery level",
     "reserve": "the battery reserve",
     "maintenance": "battery maintenance",
+    "charge": "battery maintenance",
+    "hold": "battery maintenance",
     "refused": "a battery that refuses power",
 }
 
@@ -898,6 +918,7 @@ HINTS = {
     "peak_on": "Peak guard started",
     "peak_off": "Peak guard idle",
     "peak_blind": "Peak guard cannot read the meter well",
+    "peak_gap": "Meter is back, the peak guard counts the missed time as high use",
     "peak_saturated": T_PEAK_SATURATED,
     "peak_reserve": T_PEAK_RESERVE,
     "meter_frozen": T_METER_FROZEN,
@@ -906,6 +927,8 @@ HINTS = {
     "trade_charge": "Trading: charging while the price is low",
     "trade_give": "Trading: giving power while the price is high",
     "trade_off": "Trading: waiting for a better price",
+    "forecast_read": "Solar forecast read, the day plan uses it",
+    "forecast_none": "No solar forecast, so Leftover solar takes solar only",
     "split": "The power split between inverters changed",
     "clash": "Two limits clash, inverters set to 0 W",
     "no_setpoint": "An inverter has no “Setpoint entity”, inverters stay at 0 W",
@@ -1010,6 +1033,9 @@ def status_samples() -> list:
         ("row_peak_guard_off", AMBER, row_peak_guard_off()),
         ("row_peak_reserve", RED, row_peak_reserve(
             5000, soc_unread=False, floor_unknown=False, packs=["inverter-b"])),
+        ("row_peak_reserve", RED, row_peak_reserve(
+            5000, soc_unread=False, floor_unknown=False, packs=["inverter-b"],
+            others=True)),
         ("row_peak_reserve", RED, row_peak_reserve(
             5000, soc_unread=True, floor_unknown=False)),
         ("row_peak_reserve", RED, row_peak_reserve(
@@ -1078,6 +1104,7 @@ def status_samples() -> list:
         ("row_peak_guard_idle", GREEN, row_peak_guard_idle(1300, 2500, True)),
         ("row_peak_guard_idle", GREEN, row_peak_guard_idle(1300, 2500, False)),
         ("row_peak_guard_quiet", GREEN, row_peak_guard_quiet()),
+        ("row_peak_guard_unmeasured", AMBER, row_peak_guard_unmeasured()),
         *(("row_peak_guard_blind", AMBER, row_peak_guard_blind(k))
           for k in BLIND_WORDS),
         ("row_peak_guard_on", AMBER, row_peak_guard_on(1200, 2500)),
@@ -1112,6 +1139,8 @@ def samples() -> list:
         peak_reserve(5000, soc_unread=False, floor_unknown=False),
         peak_reserve(5000, soc_unread=False, floor_unknown=False,
                      packs=["inverter-b"]),
+        peak_reserve(5000, soc_unread=False, floor_unknown=False,
+                     packs=["inverter-b"], others=True),
         peak_reserve(5000, soc_unread=True, floor_unknown=False),
         peak_reserve(5000, soc_unread=False, floor_unknown=True),
         circulating(["inverter-a"], ["inverter-b"]),
@@ -1173,6 +1202,9 @@ LABELS = {
     "batt_entity": "Battery power entity",
     "pv_entity": "Solar production entity",
     "pv_entities": "Solar production entities, per inverter",
+    "pv_forecast_entity": "Solar forecast, today",
+    "pv_forecast_tomorrow_entity": "Solar forecast, tomorrow",
+    "solar_trust_pct": "Trust in the forecast",
     "p1_phase_import_entities": "Import entities per phase",
     "p1_phase_export_entities": "Export entities per phase",
 }

goodwe_controller/app/modetrade.py

@@ -23,7 +23,11 @@ Roles (the page's Why line names them):
 
 Rules that keep this safe (tests: test_modes_p3.py):
   * every range holds 0 W (a mode may forbid a direction, never force one);
-  * a Solar first battery never charges from the grid (no forecast yet, P4);
+  * a Solar first battery never charges from the grid;
+  * P4: with a day plan (`targets`), a Leftover solar battery charges from
+    the grid only up to its planned level, never above the ceiling; with
+    none it takes solar only (P3 option A). Cheap hours only fills to the
+    ceiling either way (`charge_to()`);
   * grid charging needs a measured peak guard that is clear and a measured
     headroom (SAFETY-45); the trade is sized to that headroom, whose aim is
     `peak_cap_w - peak_margin_w` (SAFETY-79). It starts only at START_W or
@@ -47,7 +51,7 @@ Rules that keep this safe (tests: test_modes_p3.py):
 from dataclasses import dataclass
 
 from .packmode import (CHEAP_HOURS, GRID_CHARGE_MODES, LEFTOVER_SOLAR,
-                       SOLAR_FIRST)
+                       PLAN_CHARGE_MODES, SOLAR_FIRST)
 
 OFF, HOUSE, HOLD, GIVE, SELL, CHARGE, REST = (
     "off", "house", "hold", "give", "sell", "charge", "rest")
@@ -90,13 +94,35 @@ def _room_kwh(p: Pack, pct: float) -> float:
     return max(0.0, abs(pct - p.soc)) / 100.0 * float(p.capacity_kwh)
 
 
-def chargers(packs, ceiling_pct, done=()) -> list:
-    """Batteries that may charge from the grid in a cheap run: the modes in
-    `packmode.GRID_CHARGE_MODES` (Cheap hours only until P4's forecast)."""
-    return [p for p in packs
-            if p.use and p.idle and p.live and p.mode in GRID_CHARGE_MODES
-            and p.soc is not None and p.soc < ceiling_pct
-            and p.refused >= 0 and p.name not in done]
+def charge_to(p: Pack, ceiling_pct, targets=None):
+    """The level this battery may charge to from the grid, or None.
+
+    `targets` is the day plan (`dayplan.plan()`: name -> level), or None
+    when there is none (no forecast, stale, or not configured). With no plan
+    this is P3 option A exactly: Cheap hours to the ceiling, the others never.
+    With a plan, a Leftover solar battery charges only to its planned level
+    (the sun fills the rest); a battery the plan leaves out, Cheap hours only
+    included, gets the no-plan answer. Solar first never charges."""
+    if p.mode in GRID_CHARGE_MODES:
+        return float(ceiling_pct)
+    if targets is None or p.name not in targets \
+            or p.mode not in PLAN_CHARGE_MODES:
+        return None
+    t = targets[p.name]
+    return None if t is None else min(float(ceiling_pct), float(t))
+
+
+def chargers(packs, ceiling_pct, done=(), targets=None) -> list:
+    """Batteries that may charge from the grid in a cheap run: below the
+    level `charge_to()` allows them (P4: the day plan's)."""
+    out = []
+    for p in packs:
+        to = charge_to(p, ceiling_pct, targets)
+        if (to is not None and p.use and p.idle and p.live
+                and p.soc is not None and p.soc < to
+                and p.refused >= 0 and p.name not in done):
+            out.append(p)
+    return out
 
 
 def sellers(packs, floor_pct, done=()) -> list:
@@ -108,11 +134,15 @@ def sellers(packs, floor_pct, done=()) -> list:
             and p.refused <= 0 and p.name not in done]
 
 
-def energy(packs, floor_pct, ceiling_pct, done_charge=(), done_sell=()):
-    """`(charge_kwh, charge_kw, sell_kwh, sell_kw)` for `priceruns.plan()`."""
-    ch = chargers(packs, ceiling_pct, done_charge)
+def energy(packs, floor_pct, ceiling_pct, done_charge=(), done_sell=(),
+           targets=None):
+    """`(charge_kwh, charge_kw, sell_kwh, sell_kw)` for `priceruns.plan()`.
+    With a day plan the charge is each battery's shortfall, so the cheap run
+    is only as long as the shortfall needs."""
+    ch = chargers(packs, ceiling_pct, done_charge, targets)
     se = sellers(packs, floor_pct, done_sell)
-    return (sum(_room_kwh(p, ceiling_pct) for p in ch),
+    return (sum(_room_kwh(p, charge_to(p, ceiling_pct, targets))
+                for p in ch),
             sum(abs(p.rating_w) for p in ch) / 1000.0,
             sum(_room_kwh(p, floor_pct) for p in se),
             sum(abs(p.rating_w) for p in se) / 1000.0)
@@ -121,7 +151,7 @@ def energy(packs, floor_pct, ceiling_pct, done_charge=(), done_sell=()):
 def decide(runs, now, packs, *, charge_ok, sell_ok, trade_why, price_now,
            headroom_w, floor_pct, ceiling_pct, house_w, charging_now=False,
            blocked=False, done_charge=(), done_sell=(),
-           draining=False) -> Tick:
+           targets=None, draining=False) -> Tick:
     """This tick's ranges, roles and site ask.
 
     `runs` is the kept `priceruns.RunPlan` or None (no fresh prices).
@@ -132,8 +162,9 @@ def decide(runs, now, packs, *, charge_ok, sell_ok, trade_why, price_now,
     `house_w` is the measured house (grid + batteries), or None.
     `charging_now` says last tick charged (then any headroom above 0 keeps
     it going); `blocked` that the guard or the headroom stopped a charge in
-    this 15-minute period. `draining` says a battery drains for its
-    monthly cycle, so none may charge from the grid (why "cycle").
+    this 15-minute period. `targets` is the day plan (`charge_to()`).
+    `draining` says a battery drains for its monthly cycle, so none may
+    charge from the grid (why "cycle").
     """
     plan_on = runs is not None and runs.on
     in_cheap = plan_on and runs.cheap.holds(now) and runs.charge_useful()
@@ -141,7 +172,8 @@ def decide(runs, now, packs, *, charge_ok, sell_ok, trade_why, price_now,
     in_sell = plan_on and runs.sell is not None and runs.sell.holds(now)
 
     why = None
-    ch = chargers(packs, ceiling_pct, done_charge) if in_cheap else []
+    ch = chargers(packs, ceiling_pct, done_charge, targets) if in_cheap \
+        else []
     if ch and draining:
         ch, why = [], "cycle"
     charging = False

goodwe_controller/app/p1.py

@@ -312,6 +312,13 @@ class QuarterAverager:
         """
         return self._last_net
 
+    @property
+    def held_since(self) -> datetime | None:
+        """SAFETY-90: when the held sample arrived (its `ingest_ts`), or None."""
+        if self._last_t is None:
+            return None
+        return datetime.fromtimestamp(self._last_t, timezone.utc)
+
     @property
     def offtake_avg_w(self) -> float:
         """Average offtake over the part of the open block seen so far."""

goodwe_controller/app/packmode.py

@@ -46,10 +46,13 @@ SELL_KEY = "pack_sell"              # OPT-11 P3: sell in the sell run
 # refused; the sell code in modetrade/priceruns stays, unreachable.
 SELLING_ENABLED = False
 
-# The modes that may charge from the grid in a cheap run. Leftover solar joins
-# when the solar forecast exists (P4); until then it takes solar only (owner
-# decision 2026-09-29, option A).
+# The modes that may charge from the grid in a cheap run with no day plan.
+# Leftover solar takes solar only then (owner decision 2026-09-29, option A).
 GRID_CHARGE_MODES = (CHEAP_HOURS,)
+# OPT-11 P4: with a fresh solar forecast, the day plan (dayplan.py) lets
+# Leftover solar charge from the grid, by the shortfall only. Cheap hours only
+# ignores the plan (fills to the ceiling); Solar first never grid-charges.
+PLAN_CHARGE_MODES = (LEFTOVER_SOLAR,)
 
 
 def enabled(opts) -> bool:

goodwe_controller/app/peakguard.py

@@ -183,6 +183,8 @@ guard passes its own tests while being switched off:
     record). Those seconds make the projection read LOW, which is the
     under-guarding direction. The threshold is `max_hold_s` itself - the point
     p1.py already stops trusting a held sample - not a new number.
+    SAFETY-90: once readings are back, main.py counts those seconds
+    (`fill_gaps()`), so this holds only while the gap lasts.
 
   * FROZEN. SAFETY-18's conjunction, evaluated through `freeze.looks_frozen()`
     rather than re-written here. A frozen meter is the worst case of all: the
@@ -397,7 +399,7 @@ function, so whichever way the owner answers, this file does not change and does
 not need re-testing. Nothing here indexes a phase.
 """
 
-from dataclasses import dataclass
+from dataclasses import dataclass, replace
 
 from . import messages
 from .arbiter import ACTUATOR_SITE, P_PEAK, Claim
@@ -490,11 +492,18 @@ class PeakDecision:
     # floor refused to size it. Mutually exclusive with `saturated` by
     # construction: this branch asks for nothing, so it cannot have run out of
     # inverter. `soc_floor_reason` says WHICH of the two ways it bound.
+    # SAFETY-87: at N>=2 it may ask the batteries above their reserve for
+    # `able_w`, all they have, when that is not enough (`place_on_able()`).
     floor_limited: bool = False
     soc: float | None = None
     soc_floor: float | None = None
     soc_floor_reason: str | None = None
     reason: str = ""
+    # SAFETY-87, N>=2 only: the batteries at or under their own reserve,
+    # which give nothing for the peak, and what the others can give (None
+    # when they are not asked). See `place_on_able()`.
+    held: tuple = ()
+    able_w: float | None = None
 
     def explain(self) -> str:
         """Idle: the status row's plain words (UX-08). Engaged: `reason`, the
@@ -592,6 +601,57 @@ def blindness(projection, max_hold_s, frozen: bool) -> str | None:
     return None
 
 
+# SAFETY-90. Seconds of uncounted time below which nothing is filled: float
+# noise between the averager's sums and the wall clock, never a real gap.
+GAP_TOL_S = 1e-3
+
+
+def gap_w(ceiling_w, *seen_w) -> float:
+    """SAFETY-90: the watts a meter gap is counted at. The highest of the
+    limit and `seen_w`, the import with the batteries at 0 W (grid + their
+    discharge) just before and just after the gap; None entries are skipped.
+    DECISIONS/SAFETY-90-peak-guard-after-a-gap.md."""
+    return max([float(ceiling_w)] + [float(w) for w in seen_w if w is not None])
+
+
+def fill_gaps(projection, *, tail_s, max_hold_s, unseen_s, gap_w, unseen_w,
+              held_ws=0.0):
+    """SAFETY-90: `projection` with the seconds the averager did not count
+    (a meter gap past `max_hold_s`) counted at `gap_w`, and those from before
+    this run's first reading (`unseen_s`) at `unseen_w`. `held_ws` is added
+    too: what the gap's first `max_hold_s`, credited at the reading before
+    it, lacks to reach `gap_w`. Returns
+    `(projection, gap seconds filled, unseen seconds filled)`.
+
+    `tail_s` is the age of the held reading: up to `max_hold_s` of it is left
+    as before (the averager credits it once the next reading lands). Past
+    that the gap is still open, nothing is filled and `blindness()` answers
+    as before. DECISIONS/SAFETY-90-peak-guard-after-a-gap.md."""
+    if projection.block_start is None or max_hold_s is None:
+        return projection, 0.0, 0.0
+    wall = float(projection.elapsed_s)
+    tail = min(max(0.0, float(tail_s)), wall)
+    if tail > float(max_hold_s):
+        return projection, 0.0, 0.0
+    covered = wall - uncovered_s(projection)
+    missing = wall - covered - tail
+    if missing <= GAP_TOL_S:
+        missing = 0.0
+        if held_ws <= 0.0:
+            return projection, 0.0, 0.0
+    unseen = min(missing, max(0.0, float(unseen_s)))
+    gap = missing - unseen
+    add_ws = gap * float(gap_w) + unseen * float(unseen_w) + float(held_ws)
+    done = covered + missing
+    return (replace(
+        projection,
+        projected_w=float(projection.projected_w) + add_ws / QUARTER_S,
+        elapsed_w=((float(projection.elapsed_w) * covered + add_ws) / done
+                   if done > 0.0 else float(projection.elapsed_w)),
+        covered_frac=(done / wall if wall > 0.0
+                      else float(projection.covered_frac))), gap, unseen)
+
+
 def discharge_permitted(soc, soc_floor) -> str | None:
     """SAFETY-24. May the guard size a forced discharge, or why may it not?
 
@@ -733,6 +793,43 @@ def binding_soc_floor(packs, soc_floor):
     return max(floors)
 
 
+def reserve_split(packs, soc_floor) -> tuple[list, tuple]:
+    """SAFETY-87: `(packs the guard may spend, names of those it may not)`,
+    each pack graded on its own floor by `pack_permissions()`."""
+    perms = pack_permissions(packs, soc_floor)
+    return ([p for p, (_n, why) in zip(packs, perms) if why is None],
+            tuple(n for n, why in perms if why is not None))
+
+
+def place_on_able(decision, held, *, able_w, soc, soc_floor) -> PeakDecision:
+    """SAFETY-87: `decision` with the batteries in `held` (at or under their
+    own reserve) giving nothing for the peak. `able_w`, `soc` and `soc_floor`
+    describe the others, as `decide()`'s arguments do for the roster. A
+    floor-limited decision is re-taken on them: they are asked for the need
+    up to `able_w`, and it stays floor-limited only if that is not enough.
+    `soc` and `soc_floor` keep the roster's verdict, as `decide()` echoed it.
+    DECISIONS/SAFETY-87-guard-uses-able-batteries.md."""
+    held = tuple(held)
+    if not decision.floor_limited or decision.wanted_w is None \
+            or discharge_permitted(soc, soc_floor) is not None:
+        return replace(decision, held=held)
+    wanted = float(decision.wanted_w)
+    floor = min(wanted, float(able_w))
+    head = (f"this 15-minute period heads for {decision.projected_w:.0f} W "
+            f"against a {decision.ceiling_w:.0f} W limit "
+            f"({decision.ceiling_from}), aiming at {decision.target_w:.0f} W. "
+            f"At the peak reserve, so giving nothing for the peak: "
+            f"{messages.names(held)}. The others are asked for {floor:+.0f} W")
+    if floor >= wanted:
+        return replace(decision, floor_limited=False, floor_w=floor,
+                       soc_floor_reason=None, held=held, able_w=float(able_w),
+                       reason=f"PEAK_GUARD: {head}")
+    return replace(decision, floor_w=floor, held=held, able_w=float(able_w),
+                   reason=(f"PEAK_GUARD_FLOOR_LIMITED: {head}, all they can "
+                           f"give, but {wanted:+.0f} W was needed, so this "
+                           f"period may go over the limit"))
+
+
 def decide(projection, *, batt_w, cap_w, margin_w, reading, achievable_w, soc,
            soc_floor, max_hold_s=None, frozen: bool = False) -> PeakDecision:
     """The whole guard. Pure: no clock, no I/O, no state carried between calls.
@@ -1097,5 +1194,6 @@ def claim(decision: PeakDecision) -> Claim | None:
     return Claim.limit(SOURCE, P_PEAK, lo=float(decision.floor_w),
                        reason=("blind" if decision.blind
                                else "SoC floor" if decision.floor_limited
+                               and not decision.floor_w
                                else "quarter peak"),
                        actuator=ACTUATOR_SITE)

goodwe_controller/app/solarfc.py

@@ -0,0 +1,254 @@
+"""OPT-11 P4: the solar forecast, read from a Home Assistant sensor.
+
+Pure: HA state dicts and the time in, a `Forecast` (or None and why) out.
+main.py reads the entities; dayplan.py uses the answer. FCST-01 replaces
+this later with the add-on's own forecast (owner answer, 2026-09-27).
+
+Two options name the sensors: `pv_forecast_entity`, the solar energy still
+to come TODAY, and `pv_forecast_tomorrow_entity`, TOMORROW's (optional; it
+is only needed for a cheap run before midnight). Supported, by the entities
+they create (DOCS.md lists them):
+
+* Forecast.Solar (HA core): `sensor.energy_production_today_remaining` and
+  `sensor.energy_production_tomorrow`. The state only; no hourly split.
+* Solcast PV Forecast (HACS `solcast_solar`):
+  `sensor.solcast_pv_forecast_forecast_remaining_today` and
+  `..._forecast_tomorrow`, with `detailedForecast` (or `detailedHourly`):
+  `[{period_start, pv_estimate}]`, kW per period.
+* Open-Meteo Solar Forecast (HACS `open_meteo_solar_forecast`):
+  `sensor.energy_production_today_remaining` / `..._tomorrow`, with
+  `wh_period`: `{period start: Wh}`.
+
+Any other sensor whose state is energy in Wh, kWh or MWh works too, as a
+state only. The unit is read, never guessed (the rule `pv.watts()` has).
+Without an hourly split, the day's energy is spread over a fixed bell from
+06:00 to 20:00 local time (`BELL_FROM_H`, `BELL_TO_H`).
+
+A reading older than `FRESH_S`, or from before local midnight, is stale,
+and a stale or missing forecast is no forecast: the day plan is off and
+every mode acts as in P3 option A.
+"""
+
+import math
+from dataclasses import dataclass
+from datetime import datetime, timedelta, timezone
+
+from .hass import BAD_STATES
+from .tariff import BILLING_TZ
+
+KWH_PER = {"Wh": 0.001, "kWh": 1.0, "MWh": 1000.0}
+
+# Stale after 3 h. The integrations above refresh at least hourly, so a
+# 2 h limit would flag a site whose hourly poll was missed once.
+FRESH_S = 3 * 3600.0
+
+# The bell a state-only forecast is spread over, in local hours.
+BELL_FROM_H, BELL_TO_H = 6.0, 20.0
+
+# Why there is no forecast (the page words are in ui_text `home_words`).
+NOT_SET, MISSING, UNIT, STALE, BAD = (
+    "not_set", "missing", "unit", "stale", "bad")
+
+
+@dataclass(frozen=True)
+class Day:
+    """One day's forecast: `kwh` still to come (today) or in all (tomorrow),
+    and the hourly split if the sensor has one: `((start, end, kwh), ...)`."""
+    day0: datetime              # local midnight, as UTC
+    kwh: float
+    periods: tuple = ()
+
+
+@dataclass(frozen=True)
+class Forecast:
+    today: Day
+    tomorrow: Day | None
+    at: datetime                # when the sensor last reported
+
+    def between(self, t0: datetime, t1: datetime) -> float | None:
+        """kWh the sun should give between `t0` (now or later) and `t1`.
+        None when the span reaches the sunny hours of a day with no
+        forecast (tomorrow, when its sensor is not set)."""
+        if t1 <= t0:
+            return 0.0
+        last = self.tomorrow or self.today
+        if t1 > last.day0 + timedelta(days=1, hours=BELL_FROM_H):
+            return None
+        total = 0.0
+        for day in (self.today, self.tomorrow):
+            if day is None:
+                continue
+            a = max(t0, day.day0)
+            b = min(t1, day.day0 + timedelta(days=1))
+            if b > a:
+                total += _day_between(day, a, b, t0)
+        return total
+
+
+def _local_hour(t: datetime) -> float:
+    lt = t.astimezone(BILLING_TZ)
+    return lt.hour + lt.minute / 60.0 + lt.second / 3600.0
+
+
+def _bell(h: float) -> float:
+    """Cumulative share of a day's sun by local hour `h` (0..1)."""
+    if h <= BELL_FROM_H:
+        return 0.0
+    if h >= BELL_TO_H:
+        return 1.0
+    x = (h - BELL_FROM_H) / (BELL_TO_H - BELL_FROM_H)
+    return (1.0 - math.cos(math.pi * x)) / 2.0
+
+
+def _hours_since(day0, t):
+    return (t - day0).total_seconds() / 3600.0
+
+
+def _day_between(day: Day, a: datetime, b: datetime, now: datetime) -> float:
+    if day.periods:
+        out = 0.0
+        for s, e, kwh in day.periods:
+            lo, hi = max(a, s), min(b, e)
+            if hi > lo:
+                out += kwh * (hi - lo).total_seconds() / (e - s).total_seconds()
+        return out
+    # State only: `kwh` is what is left from `max(now, day0)` to the day's
+    # end, spread over the bell.
+    h_from = _hours_since(day.day0, max(now, day.day0))
+    left = 1.0 - _bell(h_from)
+    if left <= 1e-9:
+        return 0.0
+    share = (_bell(_hours_since(day.day0, b))
+             - _bell(_hours_since(day.day0, a))) / left
+    return day.kwh * max(0.0, share)
+
+
+def _parse_time(v):
+    try:
+        t = datetime.fromisoformat(str(v).replace("Z", "+00:00"))
+    except (TypeError, ValueError):
+        return None
+    return t if t.tzinfo else t.replace(tzinfo=timezone.utc)
+
+
+def _periods(attrs: dict, day0: datetime) -> tuple:
+    """The hourly split, if the sensor has one, for the day at `day0`."""
+    d1 = day0 + timedelta(days=1)
+    out = []
+    for key in ("detailedForecast", "detailedHourly"):
+        rows = attrs.get(key)
+        if isinstance(rows, list) and rows:
+            starts = []
+            for r in rows:
+                if not isinstance(r, dict):
+                    continue
+                t = _parse_time(r.get("period_start"))
+                try:
+                    kw = float(r.get("pv_estimate"))
+                except (TypeError, ValueError):
+                    continue
+                if t is not None and math.isfinite(kw) and kw >= 0:
+                    starts.append((t, kw))
+            starts.sort()
+            for i, (t, kw) in enumerate(starts):
+                step = (starts[i + 1][0] - t if i + 1 < len(starts)
+                        else timedelta(minutes=30 if key ==
+                                       "detailedForecast" else 60))
+                if step <= timedelta(0) or step > timedelta(hours=1):
+                    step = timedelta(minutes=30 if key == "detailedForecast"
+                                     else 60)
+                if day0 <= t < d1:
+                    out.append((t, t + step,
+                                kw * step.total_seconds() / 3600.0))
+            if out:
+                return tuple(out)
+    wh = attrs.get("wh_period")
+    if isinstance(wh, dict) and wh:
+        rows = []
+        for k, v in wh.items():
+            t = _parse_time(k)
+            try:
+                e = float(v)
+            except (TypeError, ValueError):
+                continue
+            if t is not None and math.isfinite(e) and e >= 0:
+                rows.append((t, e / 1000.0))
+        rows.sort()
+        for i, (t, kwh) in enumerate(rows):
+            nxt = rows[i + 1][0] if i + 1 < len(rows) else t + timedelta(
+                hours=1)
+            if nxt - t > timedelta(hours=1) or nxt <= t:
+                nxt = t + timedelta(hours=1)
+            if day0 <= t < d1:
+                out.append((t, nxt, kwh))
+    return tuple(out)
+
+
+def _day(state, day0, now, *, today):
+    """`(Day, None)` or `(None, why)` from one sensor's state dict."""
+    if state is None:
+        return None, MISSING
+    raw = str(state.get("state", "")).strip()
+    if raw.lower() in BAD_STATES:
+        return None, MISSING
+    try:
+        v = float(raw)
+    except ValueError:
+        return None, BAD
+    attrs = state.get("attributes") or {}
+    unit = str(attrs.get("unit_of_measurement") or "").strip()
+    if unit not in KWH_PER:
+        return None, UNIT
+    kwh = v * KWH_PER[unit]
+    if not math.isfinite(kwh) or kwh < 0:
+        return None, BAD
+    periods = _periods(attrs, day0)
+    if periods and today:
+        # The split is the whole day; keep what is still to come, scaled so
+        # it adds up to the state (the state is what the integration says
+        # is left).
+        left = sum(k * max(0.0, min(1.0, (e - max(s, now)).total_seconds()
+                                    / (e - s).total_seconds()))
+                   for s, e, k in periods)
+        if left > 1e-6:
+            f = kwh / left
+            periods = tuple((s, e, k * f) for s, e, k in periods)
+    return Day(day0, kwh, periods), None
+
+
+def _reported(state):
+    ts = [_parse_time(state.get(k)) for k in
+          ("last_reported", "last_updated", "last_changed")]
+    ts = [t for t in ts if t is not None]
+    return max(ts) if ts else None
+
+
+def read(today_state, tomorrow_state, now: datetime, *,
+         configured=True):
+    """`(Forecast, None)` or `(None, why)`. `tomorrow_state` may be None
+    (the option is not set, or the sensor is missing): the forecast then
+    covers today only."""
+    if not configured:
+        return None, NOT_SET
+    here = now.astimezone(BILLING_TZ)
+    d0 = datetime(here.year, here.month, here.day, tzinfo=BILLING_TZ)
+    nd = d0.date() + timedelta(days=1)
+    d1 = datetime(nd.year, nd.month, nd.day, tzinfo=BILLING_TZ)
+    day0, day1 = d0.astimezone(timezone.utc), d1.astimezone(timezone.utc)
+    today, why = _day(today_state, day0, now, today=True)
+    if today is None:
+        return None, why
+    at = _reported(today_state)
+    # A reading from before local midnight is yesterday's "left today" (0
+    # after sunset) until the integration refreshes: stale, not a dark day.
+    if at is None or at < day0 or (now - at).total_seconds() > FRESH_S \
+            or (at - now).total_seconds() > 300:
+        return None, STALE
+    tomorrow = None
+    if tomorrow_state is not None:
+        t, _w = _day(tomorrow_state, day1, now, today=False)
+        t_at = _reported(tomorrow_state)
+        if t is not None and t_at is not None and t_at >= day0 \
+                and (now - t_at).total_seconds() <= FRESH_S:
+            tomorrow = t
+    return Forecast(today, tomorrow, at), None

goodwe_controller/app/static/app.js

@@ -403,6 +403,9 @@
     else $("#batt-banner").replaceChildren();
     keepFocus(() => {
       $("#bcards").replaceChildren(...S.batteries.map(batteryCard));
+      // OPT-11 P4: the solar forecast line under the cards.
+      const sl = $("#batt-solar"), line = modes && S.solar ? S.solar.line : "";
+      if (sl) { sl.textContent = line || ""; sl.hidden = !line; }
       if (simpleHost && simpleHost.isConnected) {
         simpleHost.replaceChildren(...(modes ? S.batteries.map(simpleRow)
           : [h("p", { class: "small muted", style: "margin:4px 0" }, t("batteries.modes_off.name") + ". " + t("batteries.description"))]));

goodwe_controller/app/static/index.html

@@ -101,6 +101,7 @@
     <a class="btn" href="#settings" data-t="batteries.settings"></a>
   </div>
   <div id="bcards"></div>
+  <p class="small muted" id="batt-solar" hidden></p>
   <details class="grp" id="batt-how" hidden>
     <summary><span class="grow"><strong data-t="batteries.how.name"></strong><span class="small muted gdesc" data-t="batteries.how.description"></span></span><span class="chev" aria-hidden="true">&#8250;</span></summary>
     <div class="body small">

goodwe_controller/app/static/settings.js

@@ -446,7 +446,17 @@
       e.textContent = ok ? e.dataset.kwNote.replace("{kw}", window.UX13.kw(mp.peak_w) + " kW") : "";
     });
   }
+  // OPT-11 P4: the solar forecast card shows the add-on's forecast line.
+  function fillSolar() {
+    const st = window.UX13.status();
+    const line = st && st.solar ? st.solar.line : "";
+    document.querySelectorAll("#simple [data-solar-note]").forEach((e) => {
+      e.textContent = line || "";
+      e.hidden = !line;
+    });
+  }
   document.addEventListener("ux13:status", fillNotes);
+  document.addEventListener("ux13:status", fillSolar);
   function simpleField(f) {
     const row = fieldRow(f, null, "simple");
     row.querySelector(".head").append(chip(f.applies));
@@ -458,6 +468,7 @@
       const help = row.querySelector(".help");
       if (help) help.textContent = n.description;
     }
+    if (f.note === "forecast") row.append(h("div", { class: "small muted", "data-solar-note": "", hidden: true }));
     return h("div", { class: "card" }, row);
   }
   function renderSimple() {

goodwe_controller/app/tariff.py

@@ -822,6 +822,22 @@ class PeakTracker:
             held_w=averager.held_net_w)
 
 
+def next_quarter(p: Projection, max_hold_s: float) -> Projection:
+    """SAFETY-91: `p` past its block's end, before the next block's first
+    telegram: the next quarter, projected from the held reading (the averager
+    credits it there). `p` itself otherwise, or when that reading is too old
+    to be credited. DECISIONS/SAFETY-91-held-battery-last.md."""
+    if p.block_start is None or p.elapsed_s < QUARTER_S \
+            or p.elapsed_s * (1.0 - p.covered_frac) > float(max_hold_s):
+        return p
+    held = max(p.held_w, 0.0)
+    return Projection(projected_w=held, elapsed_w=held,
+                      elapsed_s=p.elapsed_s - QUARTER_S, covered_frac=1.0,
+                      complete=True,
+                      block_start=p.block_start + timedelta(seconds=QUARTER_S),
+                      held_w=p.held_w)
+
+
 @dataclass(frozen=True)
 class _ClosedBlock:
     """A block reconstructed from a checkpoint. Shaped like `p1.QuarterBlock` so

goodwe_controller/app/ui_text/en.json

@@ -119,7 +119,7 @@
     "description": "Every setting, grouped by task.",
     "view": {"name": "Settings view", "simple": "Simple", "installer": "Installer"},
     "simple": {"description": "The choices a home owner makes.",
-      "note": {"month_peak": {"description": "This month's peak so far: {kw}."}, "shadow": {"description": "Use Always on while you test a new installation."}},
+      "note": {"month_peak": {"description": "This month's peak so far: {kw}."}, "shadow": {"description": "Use Always on while you test a new installation."}, "forecast": {"description": "With a forecast, a battery buys only what the sun will not give."}},
       "batteries": {"name": "Batteries"},
       "more": {"description": "Looking for the meter, inverters or prices?"},
       "installer": "Open the installer view"},
@@ -335,8 +335,12 @@
       "saves": "Saves its power for {at}.",
       "saves_later": "Saves its power for higher prices.",
       "no_prices": "No prices, so it follows the house.",
-      "no_spread": "Prices differ too little, so it follows the house."
+      "no_spread": "Prices differ too little, so it follows the house.",
+      "sun_fills": "Enough sun is forecast, so it does not charge from the grid.",
+      "tops_up": "Too little sun is forecast, so it charges some from the grid.",
+      "no_forecast": "No solar forecast, so it charges from solar only."
     },
+    "solar": {"line": "Solar still to come today: {kwh}, we count on {count}. Updated {at}.", "no_forecast": "No solar forecast now, so Leftover solar charges from solar only.", "learning": "The add-on is learning your house's use. The plan starts after one full day."},
     "today": {
       "not_planned": "Not planned yet.",
       "no_runs": "No cheap or expensive hours left today.",
@@ -406,6 +410,7 @@
     "step_in": "The batteries step in above {kw}.",
     "step_in_would": "The batteries would step in above {kw}.",
     "period": "This 15-minute period is heading for {kw}.",
+    "period_unmeasured": "Part of this 15-minute period was not measured.",
     "prices": {
       "now": "Price now {eur} per kWh, all in.",
       "today": "Today: lowest {lo} at {lo_at}, highest {hi} at {hi_at}.",

goodwe_controller/app/ui_text/nl.json

@@ -114,7 +114,7 @@
     "description": "Elke instelling, per taak.",
     "view": {"name": "Weergave van de instellingen", "simple": "Eenvoudig", "installer": "Installateur"},
     "simple": {"description": "De keuzes die een eigenaar maakt.",
-      "note": {"month_peak": {"description": "De piek van deze maand tot nu: {kw}."}, "shadow": {"description": "Kies Altijd aan terwijl u een nieuwe installatie test."}},
+      "note": {"month_peak": {"description": "De piek van deze maand tot nu: {kw}."}, "shadow": {"description": "Kies Altijd aan terwijl u een nieuwe installatie test."}, "forecast": {"description": "Met een prognose koopt een batterij alleen wat de zon niet geeft."}},
       "batteries": {"name": "Batterijen"},
       "more": {"description": "Zoekt u de meter, de omvormers of de prijzen?"},
       "installer": "De installateursweergave openen"},
@@ -277,8 +277,12 @@
       "saves": "Spaart haar stroom voor {at}.",
       "saves_later": "Spaart haar stroom voor hogere prijzen.",
       "no_prices": "Geen prijzen, dus ze volgt het huis.",
-      "no_spread": "De prijzen verschillen te weinig, dus ze volgt het huis."
+      "no_spread": "De prijzen verschillen te weinig, dus ze volgt het huis.",
+      "sun_fills": "Er is genoeg zon voorspeld, dus ze laadt niet van het net.",
+      "tops_up": "Te weinig zon voorspeld, dus ze laadt wat van het net.",
+      "no_forecast": "Geen zonneprognose, dus ze laadt alleen met zonne-energie."
     },
+    "solar": {"line": "Nog verwachte zon vandaag: {kwh}, we rekenen op {count}. Bijgewerkt om {at}.", "no_forecast": "Nu geen zonneprognose, dus Overschot zonne-energie laadt alleen met zon.", "learning": "De add-on leert eerst het verbruik van uw huis. Het plan start na één volle dag."},
     "today": {
       "not_planned": "Nog niet gepland.",
       "no_runs": "Vandaag geen goedkope of dure uren meer.",
@@ -343,6 +347,7 @@
     "step_in": "De batterijen springen bij boven {kw}.",
     "step_in_would": "De batterijen zouden bijspringen boven {kw}.",
     "period": "Dit kwartier gaat richting {kw}.",
+    "period_unmeasured": "Een deel van dit kwartier is niet gemeten.",
     "prices": {"now": "Prijs nu {eur} per kWh, alles inbegrepen.", "today": "Vandaag: laagste {lo} om {lo_at}, hoogste {hi} om {hi_at}.", "none": "Geen prijzen voor vandaag."},
     "tomorrow": {"known": "De prijzen van morgen zijn binnen.", "unknown": "De prijzen van morgen komen meestal na 13:00."},
     "region": {"preset": "Heffingen en btw: {region}, cijfers van {year}.", "own": "Heffingen en btw: uw eigen bedrag."},

goodwe_controller/app/uilayout.py

@@ -129,7 +129,14 @@ GROUPS = (
                              wizard=3),)),
         # OPT-11: the switch that turns battery modes on. Each battery's mode
         # and on/off switch are runtime state on the Batteries screen.
-        Part("modes", (Field("battery_modes_enabled", TOGGLE),)),
+        Part("modes", (
+            Field("battery_modes_enabled", TOGGLE),
+            # OPT-11 P4: the solar forecast; today's also on Settings, Simple.
+            Field("pv_forecast_entity", ENTITY, kind="energy", simple=True,
+                  note="forecast"),
+            Field("pv_forecast_tomorrow_entity", ENTITY, kind="energy"),
+            Field("solar_trust_pct", SLIDER, "%", step=5),
+        )),
     )),
     Group("tariff", (
         Part("", (

goodwe_controller/app/validate.py

@@ -246,6 +246,10 @@ NOT READY banner already names the problem, (b) does not apply.
  12. `peak_margin_w` outside 0-500 W, not whole, or not below `peak_cap_w`.
      SAFETY-79; the Supervisor checks the range too, but not for sim/inject.py.
 
+ 13. OPT-11 P4: `solar_trust_pct` outside 30-100 or not whole, or a solar
+     forecast entity that is not a `sensor.` id. A trust of 0 or 500 % would
+     make the day plan buy everything or nothing, which no one means.
+
 WHAT IS DELIBERATELY *NOT* REFUSED, because it is untidy rather than unsafe:
 
   - `integrator_max_w` above `max_w`. DOCS.md is right that the only thing the
@@ -324,9 +328,10 @@ WHAT IS DELIBERATELY *NOT* REFUSED, because it is untidy rather than unsafe:
 """
 
 import logging
+import re
 from typing import NamedTuple
 
-from . import messages, pv
+from . import dayplan, messages, pv, solarfc
 from .arbitrage import enabled as arbitrage_on
 from .control import SLEW_RAIL_FRAC, LOOP_TICK_S, PLANT_SETTLE_S
 from .custom_formula import (
@@ -1199,6 +1204,7 @@ def validate_startup_config(opts: dict, dev_min=None, dev_max=None,
 
     # --- 12. SAFETY-79: the margin the peak guard keeps under the limit -----
     problems += _margin_problems(opts)
+    problems += _forecast_problems(opts)
 
     # --- warnings: real, but not worth refusing over -------------------------
     integ = opts.get("integrator_max_w")
@@ -1751,6 +1757,8 @@ def _entities_read(opts: dict) -> list[tuple[str, str, str]]:
     add("pv_entities" if solar else "pv_entity", list(pv.entities(opts)))
     for key in ("peak_forecast_entity", "price_now_entity", "price_avg_entity"):
         add(key, opts.get(key))
+    for key in FORECAST_KEYS:
+        add(key, opts.get(key))
     return out
 
 
@@ -1790,6 +1798,19 @@ def _entity_notes(notes, opts: dict, entities: dict, bad=()) -> None:
             _advise(notes, "warn", (key,),
                     f"{entity} reads in {unit}, but {S(key, where)} is "
                     "taken as watts, so pick a sensor in W.")
+        if key in FORECAST_KEYS and unit not in solarfc.KWH_PER:
+            _advise(notes, "warn", (key,),
+                    f"{entity} does not read in kWh, so pick a solar "
+                    "forecast sensor in kWh.")
+    if any(opts.get(k) for k in FORECAST_KEYS) and \
+            opts.get("battery_modes_enabled") is not True:
+        _advise(notes, "info", ("pv_forecast_entity",),
+                "The solar forecast is used only with battery modes on.")
+    if opts.get("pv_forecast_tomorrow_entity") and \
+            not opts.get("pv_forecast_entity"):
+        _advise(notes, "warn", ("pv_forecast_tomorrow_entity",),
+                "Tomorrow's forecast is used only with today's, so set "
+                f"{S('pv_forecast_entity')} too.")
 
 
 # --------------------------------------------------------------------------- #
@@ -2045,6 +2066,33 @@ def _margin_problems(opts: dict) -> list[str]:
     return []
 
 
+TRUST_RANGE_PCT = (30, 100)
+# A Home Assistant sensor id; it goes into the /api/states/<id> path.
+_SENSOR_ID = re.compile(r"sensor\.[a-z0-9_]+")
+FORECAST_KEYS = ("pv_forecast_entity", "pv_forecast_tomorrow_entity")
+
+
+def _forecast_problems(opts: dict) -> list[str]:
+    """Rule 13 (OPT-11 P4): the trust is a whole percentage in range, and
+    each forecast entity set is a sensor."""
+    out = []
+    raw = opts.get("solar_trust_pct")
+    trust = _number(opts, "solar_trust_pct", dayplan.DEFAULT_TRUST_PCT)
+    lo, hi = TRUST_RANGE_PCT
+    if trust is None or trust != int(trust) or not lo <= trust <= hi:
+        out.append(f"{S('solar_trust_pct')} must be a whole number from {lo} "
+                   f"to {hi} %. It is {messages.shown(raw)}.")
+    for key in FORECAST_KEYS:
+        e = opts.get(key)
+        if e is None or e == "":
+            continue
+        if not isinstance(e, str) or not _SENSOR_ID.fullmatch(e):
+            out.append(f"{S(key)} must be a sensor, like "
+                       f"sensor.energy_production_today_remaining. It is "
+                       f"{messages.shown(e)}.")
+    return out
+
+
 def _number(opts: dict, key, default):
     raw = opts.get(key, default)
     if raw is None or raw == "":