"""WHICH STORE THIS DEPLOYMENT IS ALLOWED TO WRITE — the fail-closed binding (D-315 / D-298).

⛔⛔ THE SENTENCE THIS FILE EXISTS TO MAKE IMPOSSIBLE. Owner, 2026-08-18, verbatim: *"this is so
critical that whenever we do staging, we don't fuck up anyone's data. EVER."* It had already
happened once: `fsanyoto/loopable` became STAGING on 2026-08-14 having never been given a store of
its own, so two different builds wrote tenant #0's real business data. Compose that with D-305
(the store is last-write-wins at whole-document granularity) and a routine staging deploy does not
merely add test rows — it can erase a real user's views, fields and typed cell values.

⛔ A DEPLOY FLAG IS NOT THE FIX; THE FLAG IS THE THING THAT ALREADY FAILED. The isolation that
existed was bound to a ROLE ("the staging Space"), and a guard bound to a role stops guarding the
moment the role moves — which these two Spaces have done twice. So the binding here is on the
container's OWN IDENTITY, which no deploy can forget to pass and no role swap can invalidate.

⭐⭐ THE RULE, AND IT CLASSIFIES THE DEPLOYMENT RATHER THAN THE REPO:

    1. the PRODUCTION deployment (identity in `PRODUCTION_SPACES`)  -> may write anything
    2. any other deployment writing a KNOWN production store        -> REFUSED
    3. any other deployment writing a repo on its OWN allowlist     -> allowed
    4. anything else                                                -> REFUSED

⛔ WHY NOT CLASSIFY THE REPO, which is the design everybody reaches for first. A DENYLIST of
production stores fails OPEN for the next tenant nobody remembered to add. A SUFFIX RULE
(`*-staging-data`) pins a SPELLING rather than a claim — see [[gate-pins-a-spelling-not-a-claim]] —
and a store named without the suffix is unprotected while reading as protected. Rule 4 is the one
that survives a tenant nobody has provisioned yet: an unknown repo is refused, so a store this
deployment was never handed cannot be written by accident.

⭐⭐ AND RULE 4 IS NOT THEORETICAL — IT IS THE HALF OF D-315 THE REGISTER ROW DID NOT KNOW ABOUT.
Measured 2026-08-18 by reading both control planes: `royal-imports/cfo-os-staging-data`'s own
`tenants.json` is byte-identical to live's and names **`royal-imports/aios-nurilab-data`,
`aios-gtmlab-data` and `aios-loopable-data`** — the three other tenants' REAL stores. So
`--data-repo=` only ever isolated tenant #0; `harness/runtime.py`'s `store.for_repo(repo)` path
resolved three PRODUCTION repos out of the staging store and wrote them, and no flag has ever
touched that path. The exposure is FOUR production stores, not one.

⚠ READS ARE NOT REFUSED, AND THAT IS A DELIBERATE, STATED SCOPE DECISION. `Store.get` is lenient
by contract: a refused read would hand back `{}`, a caller would paint an empty grid, and the whole
Space would read as "no data" rather than as "refused" — the exact
[[empty-answer-vs-unfinished-answer]] shape this codebase has shipped before. A refused WRITE is
loud (503, with the reason). So staging still SEES production data when pointed at it; it can no
longer CHANGE it. Narrowing the read is a separate decision and is booked, not smuggled in here.

⚠ ABSENT IDENTITY FAILS CLOSED, AND THE FAILURE LOOKS LIKE AN OUTAGE. If a container exposes none
of the identity variables, it is treated as "not the production deployment" and every write to a
production store refuses. That is the safe direction, but on a live Space it would read as a total
product outage — which is why `describe()` reports the RAW observations and not just the verdict:
per D-160 the Space environment cannot be read from outside, so the container has to say what it
saw. One deploy then answers "does SPACE_ID exist here", instead of three.
"""
import os

#: The deployment that OWNS production data. A frozenset rather than a string because the product
#: has had two public addresses before and will again.
#:
#: ⚠ THIS SET IS DUPLICATED IN `aios-web/deploy_web.py` AS `PUBLIC_LIVE`, on purpose and with a
#: gate: `deploy_web` is a standalone CLI that must run without the platform package importable, so
#: it cannot import this. `verify_store_binding.py::section_constants` asserts the two literals
#: agree — a constant two features share is a constant that drifts ([[constant-two-features-share]]).
PRODUCTION_SPACES = frozenset({'fsanyoto/runloopable'})

#: The stores that hold REAL customer business data. Enumerated 2026-08-18 from the live control
#: plane (`royal-imports/cfo-os-data::tenants.json`), not guessed.
#:
#: ⛔ THIS LIST IS RULE 2, NOT THE WHOLE GUARD. It exists to make a DELIBERATE mis-pointing loud —
#: `OS_DATA_REPO=royal-imports/cfo-os-data` typed on a laptop, or a production repo added to a
#: sandbox allowlist by hand. Rule 4 is what covers a tenant provisioned after this line was
#: written, which is why the file does not depend on this staying complete.
PRODUCTION_STORES = frozenset({
    'royal-imports/cfo-os-data',            # tenant #0 — Royal Imports
    'royal-imports/aios-nurilab-data',      # Nurilab
    'royal-imports/aios-gtmlab-data',       # GTM Lab
    'royal-imports/aios-loopable-data',     # Loopable
})

#: The historical default of `OS_DATA_REPO`. Kept as a name so the resolution below can say what it
#: is refusing to assume, rather than repeating a literal.
PRODUCTION_DEFAULT_STORE = 'royal-imports/cfo-os-data'

#: The env vars a Hugging Face Space container sets to describe itself, in the order they are
#: trusted. `SPACE_ID` is the canonical one; the pair is the documented fallback. Read as a LIST so
#: `describe()` can report every one of them and what it held.
_IDENTITY_VARS = ('SPACE_ID', 'SPACE_AUTHOR_NAME', 'SPACE_REPO_NAME', 'SPACE_HOST')

#: The env a NON-production deployment uses to name the stores it may write, beyond `OS_DATA_REPO`.
#: Comma-separated.
#:
#: ⭐ THE POLARITY IS THE POINT, and it is what keeps trap 1 satisfied. Forgetting to set this
#: makes a deployment write LESS, never more — so an omitted deploy argument is a refusal, not a
#: silent grant. That is the exact inverse of `--data-repo`, whose omission printed
#: "OS_DATA_REPO unchanged" and left a Space on production.
_SANDBOX_STORES_VAR = 'AIOS_SANDBOX_STORES'

#: The local (no-identity) escape hatch. Present ⇒ writes to production stores are permitted from a
#: machine with no Space identity, AND every commit this process makes is stamped distinguishably
#: (see `local_commit_suffix`). Deliberately does NOT widen a Space: a container that HAS an
#: identity and is not production is refused with no override, because that is the case the owner
#: said "EVER" about.
_LOCAL_OPT_IN_VAR = 'AIOS_ALLOW_PRODUCTION_DATA'


class StoreWriteRefused(RuntimeError):
    """A write this deployment is not allowed to make.

    ⛔ DELIBERATELY NOT A SUBCLASS OF `grid_events.StoreUnavailable`, and the reason is the routes.
    Several of them carry `except StoreUnavailable:` blocks that DEGRADE to a session-scoped
    fallback workspace — correct for an outage, catastrophic for a refusal, because the user would
    be told the change was saved somewhere. A distinct type falls through all of them to the
    app-level handler, which answers 503 with the reason and never claims a save.
    """


def _env(name):
    return str(os.environ.get(name) or '').strip()


def deployment_id():
    """This container's own identity, or `''` when it is not a Space (i.e. local dev).

    ⚠ NOT DERIVED FROM ANY DEPLOY ARGUMENT. That is the whole design: `SPACE_ID` is set by the
    platform inside the container, so it cannot be forgotten, mistyped, or left behind by a Space
    that changed role without being redeployed.
    """
    sid = _env('SPACE_ID')
    if sid:
        return sid
    author, repo = _env('SPACE_AUTHOR_NAME'), _env('SPACE_REPO_NAME')
    if author and repo:
        return f'{author}/{repo}'
    return ''


def is_production_deployment():
    """True only on the deployment that owns production data. Unknown ⇒ False (fail closed)."""
    return deployment_id() in PRODUCTION_SPACES


def is_space():
    """True when this process is running inside a Space at all.

    The distinction matters exactly once: a Space that is not production gets NO override, while a
    laptop does. `deployment_id()` conflates them into `''`, so ask separately.
    """
    return bool(deployment_id())


def sandbox_allowlist():
    """The repos a non-production deployment may write: `OS_DATA_REPO` + `AIOS_SANDBOX_STORES`."""
    allowed = {r.strip() for r in _env(_SANDBOX_STORES_VAR).split(',') if r.strip()}
    own = _env('OS_DATA_REPO')
    if own:
        allowed.add(own)
    return frozenset(allowed)


def local_override():
    """True when a machine with no Space identity has explicitly opted in to production data."""
    return (not is_space()) and _env(_LOCAL_OPT_IN_VAR) == '1'


def default_store():
    """What `OS_DATA_REPO` resolves to when it is unset.

    ⛔⛔ FACT (1) OF D-315 DIES HERE: `core/store.py` used to read
    `os.environ.get('OS_DATA_REPO', 'royal-imports/cfo-os-data')`, so a Space that was never given
    the key — every NEW Space, by construction — came up bound to tenant #0's real business data.
    The default now exists ONLY on the deployment that owns it.

    ⚠ IT STILL RETURNS THE PRODUCTION ID ELSEWHERE, RATHER THAN `None` OR `''`, AND THAT IS
    DELIBERATE. A `None` repo would make `Store.__init__` — which runs at IMPORT time via
    `_DEFAULT = for_repo(REPO)` — raise or bind something nonsensical, killing the app and every
    gate on any non-production machine. Returning the real id keeps binding total and lets
    `write_refusal` refuse the WRITE with a message that names the actual problem. Reads still
    work, so a developer sees a populated app that will not let them damage it.
    """
    return PRODUCTION_DEFAULT_STORE


def write_refusal(repo):
    """`None` if this deployment may write `repo`, else the sentence explaining why not.

    ⭐ RETURNS A REASON RATHER THAN A BOOL, because [[report-the-cause-before-you-fix-it]]: a
    silent refusal makes every theory about it unfalsifiable, and this one fires on a path where
    the operator cannot read the container's environment (D-160).
    """
    rid = str(repo or '').strip()
    if not rid:
        return ('no store repo is bound. Refusing to guess: an unnamed store is how a deployment '
                'ends up on somebody else\'s data.')
    if is_production_deployment():
        return None                                   # rule 1 — the live Space owns its data
    if rid in PRODUCTION_STORES:                      # rule 2 — never, from anywhere else
        if local_override():
            return None
        who = deployment_id() or 'this machine (no Space identity)'
        if is_space():
            return (f'{who} is not the production deployment, so it may not write {rid}, which '
                    f'holds real customer data. Point this Space at its own store with '
                    f'--data-repo=, or add it to {_SANDBOX_STORES_VAR}. There is no override for '
                    f'a Space: a build that is not live never writes live data.')
        return (f'{who} may not write {rid}, which holds real customer data. Set OS_DATA_REPO to a '
                f'sandbox store, or set {_LOCAL_OPT_IN_VAR}=1 to opt in deliberately (every commit '
                f'is then stamped as a local write so it can be told apart afterwards).')
    allow = sandbox_allowlist()                       # rule 3 — what it was explicitly handed
    if rid in allow:
        return None
    who = deployment_id() or 'this machine (no Space identity)'
    listed = ', '.join(sorted(allow)) or '(nothing)'
    return (f'{who} was not given {rid}. A non-production deployment may write only the stores it '
            f'was handed: {listed}. Add it to {_SANDBOX_STORES_VAR} if that is intended.')


def check_write(repo, operation='write'):
    """Raise `StoreWriteRefused` unless this deployment may write `repo`. The one enforcement door."""
    reason = write_refusal(repo)
    if reason:
        raise StoreWriteRefused(f'{operation} to {repo!r} refused: {reason}')


def local_commit_suffix():
    """A marker appended to commit messages made under the local override, else `''`.

    ⭐ THIS IS THE SECOND HALF OF D-298's EXIT CONDITION, satisfied rather than argued around: *"a
    local run either cannot reach the live store without an explicit opt-in, OR stamps its commits
    distinguishably"*. The measured complaint was that a laptop's commits were titled
    `update user_tables` — byte-identical to what the live Space writes every few minutes — so a
    local run and production were indistinguishable in the store's git history, which is the ONLY
    audit trail this product has. Both clauses now hold: the opt-in is required AND it stamps.
    """
    if not local_override():
        return ''
    import getpass                                   # noqa: PLC0415 — only on the opt-in path
    import socket                                    # noqa: PLC0415
    try:
        who = getpass.getuser()
    except Exception:                                # noqa: BLE001
        who = 'unknown'
    try:
        host = socket.gethostname()
    except Exception:                                # noqa: BLE001
        host = 'unknown'
    return f' [LOCAL DEV {who}@{host}]'


def describe(repo=None):
    """What this container sees about itself — the payload behind the status field.

    ⛔ IT REPORTS THE RAW OBSERVATIONS, NOT ONLY THE VERDICT, and that is the point rather than
    debug noise. D-160 established that a Space's environment cannot be read from outside, so
    "is staging on the right store?" is a question only the container can answer. A verdict alone
    ("production: false") cannot distinguish "SPACE_ID says staging" from "SPACE_ID does not exist
    on this platform at all" — two states with the same verdict and completely different fixes.
    Reporting the variables makes ONE deploy answer it.

    ⚠ Carries no secret: a Space id and a dataset repo id are public names. The DATA is not, and
    none of it is here. The field is session-gated anyway (see `routes_admin.settings`).
    """
    rid = str(repo or '').strip()
    return {
        'deployment': deployment_id(),
        'production': is_production_deployment(),
        'repo': rid,
        'writable': write_refusal(rid) is None if rid else False,
        'refusal': write_refusal(rid) if rid else None,
        'localOverride': local_override(),
        'allowlist': sorted(sandbox_allowlist()),
        # The raw half. `''` means "the variable is absent", which is itself the answer on a
        # platform that does not set it.
        'observed': {name: _env(name) for name in _IDENTITY_VARS},
    }