#!/usr/bin/env python3
"""Create the roadmap milestones in Gitea.

Milestones mirror the phases in llmgw-plan.md §11 and the versions in
CHANGELOG.md, so an issue can be filed against the phase that owns it.

Idempotent: a milestone whose title already exists is left untouched, including
its state and due date. Nothing is ever deleted.

Usage:
    GITEA_TOKEN=<token> scripts/gitea/milestones.py [--repo ilker/llmgw] [--dry-run]

The token needs write access to the repository. Create one under
Settings → Applications → Access Tokens with the `write:issue` scope.
"""

import argparse
import json
import os
import sys
import urllib.error
import urllib.request

DEFAULT_INSTANCE = "https://gitea.mynodes.xyz"
DEFAULT_REPO = "ilker/llmgw"

# Due dates are derived from the durations in plan §11 laid end to end from
# 2026-09-16. They are estimates, not commitments; adjust them in Gitea rather
# than here once reality disagrees.
MILESTONES = [
    {
        "title": "v0.1.0 — Phase 0: skeleton and sim-engine",
        "description": (
            "CLI skeleton plus the fake inference engine everything else is tested "
            "against. Exit criterion: sim-engine models batching, KV blocks, prefix "
            "caching and cancellation, and exposes the §7.6 metric contract."
        ),
        "due_on": "2026-09-16T12:00:00Z",
        "closed": True,
    },
    {
        "title": "v0.2.0 — Phase 1: static router",
        "description": (
            "OpenAI handlers, streaming proxy with cancellation propagation, a static "
            "endpoint list, the filter/score/pick pipeline and metric scraping.\n\n"
            "Exit criterion: 1000 concurrent streams behind 3 sim-engines; upstream "
            "cancellation on client disconnect verified; router overhead p99 < 2 ms."
        ),
        "due_on": "2026-09-30T12:00:00Z",
    },
    {
        "title": "v0.3.0 — Phase 1.5: admission control",
        "description": (
            "Saturation detector, priority bands, round-robin tenant fairness, queue "
            "capacity and TTL.\n\n"
            "Exit criterion: while 500 concurrent batch requests flow through the "
            "bronze band, interactive TTFT p99 in the platinum band stays under 1.5x "
            "its idle value. This test stays in CI permanently."
        ),
        "due_on": "2026-10-07T12:00:00Z",
    },
    {
        "title": "v0.4.0 — Phase 2: agent",
        "description": (
            "GPU and IB discovery, the engine interface, the process supervisor and "
            "the control plane stream.\n\n"
            "Exit criterion: start and stop a model on a real node via ctl."
        ),
        "due_on": "2026-10-21T12:00:00Z",
    },
    {
        "title": "v0.5.0 — Phase 3: control plane",
        "description": (
            "SQLite store, catalog, inventory, single-node placement, reconciler, and "
            "a dynamic EndpointSource for the router.\n\n"
            "Exit criterion: shutting down a node moves its replicas elsewhere while "
            "the router keeps serving."
        ),
        "due_on": "2026-11-11T12:00:00Z",
    },
    {
        "title": "v0.6.0 — Phase 4: multi-node and fabrics",
        "description": (
            "Fabric identity, multi-node placement under the fabric constraint, NCCL "
            "environment generation, replica-level failure handling.\n\n"
            "Exit criterion: a 2-node replica on each fabric; killing a node rebuilds "
            "the replica on the same fabric and never spreads it across two."
        ),
        "due_on": "2026-11-25T12:00:00Z",
    },
    {
        "title": "v1.0.0 — Phase 5: production features",
        "description": (
            "Tenancy and budgets, routing profiles from configuration, the approximate "
            "prefix tree, fallback models and pool spillover, ctl bench, tracing, "
            "systemd units and documentation."
        ),
        "due_on": "2026-12-16T12:00:00Z",
    },
    {
        "title": "Phase 6 — v2 ideas",
        "description": (
            "No due date; a parking lot. Precise KV index, admission displacement, "
            "autoscaling with preemption, control plane HA, prefill/decode "
            "disaggregation, LoRA routing, external providers, admin UI."
        ),
    },
]


def request(method, url, token, payload=None):
    data = json.dumps(payload).encode() if payload is not None else None
    req = urllib.request.Request(url, data=data, method=method)
    req.add_header("Authorization", f"token {token}")
    req.add_header("Content-Type", "application/json")
    try:
        with urllib.request.urlopen(req, timeout=30) as resp:
            body = resp.read()
            return json.loads(body) if body else None
    except urllib.error.HTTPError as e:
        detail = e.read().decode(errors="replace")[:300]
        raise SystemExit(f"{method} {url} failed: {e.code} {detail}") from e


def main():
    ap = argparse.ArgumentParser(description=__doc__)
    ap.add_argument("--instance", default=os.environ.get("GITEA_INSTANCE", DEFAULT_INSTANCE))
    ap.add_argument("--repo", default=os.environ.get("GITEA_REPO", DEFAULT_REPO))
    ap.add_argument("--dry-run", action="store_true", help="show what would be created")
    args = ap.parse_args()

    token = os.environ.get("GITEA_TOKEN", "")
    if not token and not args.dry_run:
        sys.exit("GITEA_TOKEN is not set (use --dry-run to preview)")

    base = f"{args.instance.rstrip('/')}/api/v1/repos/{args.repo}/milestones"

    existing = {}
    if not args.dry_run:
        for m in request("GET", f"{base}?state=all&limit=100", token) or []:
            existing[m["title"]] = m

    for spec in MILESTONES:
        title = spec["title"]
        if title in existing:
            print(f"skip    {title}  (already exists, id={existing[title]['id']})")
            continue
        if args.dry_run:
            print(f"create  {title}")
            continue

        payload = {"title": title, "description": spec.get("description", "")}
        if "due_on" in spec:
            payload["due_on"] = spec["due_on"]

        created = request("POST", base, token, payload)
        print(f"create  {title}  (id={created['id']})")

        # The create endpoint ignores `state`, so close it separately.
        if spec.get("closed"):
            request("PATCH", f"{base}/{created['id']}", token, {"state": "closed"})
            print(f"close   {title}")


if __name__ == "__main__":
    main()