"""Owner-configured runtime and scheduled durable audit delivery.

This loads explicit configuration; it neither provisions credentials nor admits
a deployment. Projected caller tokens and Audit Core sender custody have owners.
"""

from dataclasses import dataclass
from datetime import datetime, timezone
import json
import os
from pathlib import Path
import stat
import tempfile
import threading
import time

from .approval_http import ApprovalHTTPClient
from .audit import AuditCoreSink, OutboxWorker
from .policy import PolicyClient
from .review import ReviewController
from .store import Store


def token_file(path):
    path = Path(path)
    if not path.is_absolute():
        raise ValueError("credential file path must be absolute")
    def read():
        with path.open("rb") as handle:
            value = handle.read(32769)
        if len(value) > 32768:
            raise ValueError("credential file too large")
        return value.decode("ascii").strip()
    return read


class AuditPump:
    """One process, bounded batches, 30s ticks; never drops a failed record."""
    def __init__(self, store, sink, *, clock=time.time):
        self.store, self.worker, self.clock = store, OutboxWorker(store, sink), clock
        self._stop = threading.Event()
        self._thread = None
        self._lock = threading.Lock()
        self._last_ok = None
        self._last_reconciled = 0

    def ready(self):
        with self._lock:
            return self._last_ok is not None and self.clock() - self._last_ok < 90

    def tick(self):
        try:
            self.store.queue_heartbeats()
            result = self.worker.run_once(limit=10)
            now = self.clock()
            if now - self._last_reconciled >= 300:
                stamp = lambda t: datetime.fromtimestamp(t, timezone.utc).isoformat(timespec="microseconds")
                report = self.worker.reconcile(stamp(now - 86400), stamp(now))
                # Report the two time bases, not an invented loss/completeness
                # result. A retained private snapshot is for operator inspection.
                directory = self.store.path.parent
                fd, temporary = tempfile.mkstemp(prefix=".reconciliation-", dir=directory)
                try:
                    with os.fdopen(fd, "w") as handle:
                        json.dump(report, handle, sort_keys=True)
                        handle.write("\n"); handle.flush(); os.fsync(handle.fileno())
                    os.replace(temporary, directory / "audit-reconciliation.json")
                finally:
                    if os.path.exists(temporary):
                        os.unlink(temporary)
                self._last_reconciled = now
            healthy = not result["retrying"] and not result["blocked"] and not any(
                row["state"] != "delivered" for row in self.store.outbox())
            with self._lock:
                self._last_ok = now if healthy else None
        except Exception:
            # Keep readiness closed and retry next tick. Never log response
            # bodies, file paths, bearer tokens or a fabricated human decline.
            with self._lock:
                self._last_ok = None

    def start(self):
        if self._thread is not None:
            raise RuntimeError("audit delivery already started")
        def run():
            while not self._stop.is_set():
                self.tick()
                self._stop.wait(30)
        self._thread = threading.Thread(target=run, name="infd-audit-delivery", daemon=True)
        self._thread.start()

    def stop(self):
        self._stop.set()
        if self._thread is not None:
            self._thread.join(timeout=6)


@dataclass(frozen=True)
class Runtime:
    controller: ReviewController
    pump: AuditPump

    @classmethod
    def from_file(cls, filename):
        path = Path(filename)
        info = path.lstat()
        if (not path.is_absolute() or not stat.S_ISREG(info.st_mode) or info.st_nlink != 1
                or info.st_uid != os.getuid() or stat.S_IMODE(info.st_mode) != 0o600
                or info.st_size > 16384):
            raise ValueError("runtime configuration must be an owned private 0600 file")
        data = json.loads(path.read_text())
        if (set(data) != {"schema", "evidence_db", "policy", "approval_origin", "audit"}
                or data["schema"] != "informed-decision.review-runtime.v1"
                or set(data["policy"]) != {"origin", "package", "version", "package_digest", "caller_token_file"}
                or set(data["audit"]) != {"origin", "sender_token_file"}):
            raise ValueError("invalid review runtime configuration")
        if not Path(data["evidence_db"]).is_absolute():
            raise ValueError("absolute evidence database path required")
        from .http_transport import fixed_origin
        approval_origin = fixed_origin(data["approval_origin"], allow_internal_http=True)
        policy = data["policy"]
        client = PolicyClient(policy["origin"], token_file(policy["caller_token_file"]),
            package=policy["package"], version=policy["version"], package_digest=policy["package_digest"],
            allow_internal_http=True)
        sink = AuditCoreSink(data["audit"]["origin"], token_file(data["audit"]["sender_token_file"]),
                             allow_internal_http=True)
        store = Store(data["evidence_db"])
        controller = ReviewController(store, client, lambda session: ApprovalHTTPClient(
            approval_origin, session, allow_internal_http=True))
        return cls(controller, AuditPump(store, sink))