#!/usr/bin/env python3
"""ETL VPS → ClickHouse (cada 5min). Corre EN el VPS datardos (no en el PC) porque
popelis-db (Postgres) solo es alcanzable en la red coolify. Lee popelis-db via
`docker exec popelis-db psql` y empuja a ClickHouse por su HTTP local (127.0.0.1:8123).

Standalone a proposito: el VPS no tiene el registry fn_registry checkouteado, asi que
no importa clickhouse_insert_rows_py_infra — replica el POST JSONEachRow minimal.

- users, mylist: snapshot completo cada run (snapshot_ts).
- events: incremental por id (> max(event_id) ya en CH; ReplacingMergeTree dedup).

Lee creds de /opt/analytics/.env (CH_PASSWORD). Pensado para systemd timer en el VPS.
Uso: sudo python3 etl_vps.py
"""
import json
import subprocess
import sys
import urllib.request
import urllib.parse
import urllib.error
from datetime import datetime, timezone

ENV = "/opt/analytics/.env"
CH_URL = "http://127.0.0.1:8123"
CH_USER = "analytics"
CH_DB = "analytics"
PG_CONTAINER = "popelis-db"
PG_USER = "popelis"
PG_DB = "popelis"
SNAP = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%S")


def ch_password():
    with open(ENV) as f:
        for line in f:
            if line.startswith("CH_PASSWORD="):
                return line.strip().split("=", 1)[1]
    raise RuntimeError("CH_PASSWORD no en " + ENV)


CH_PASS = ch_password()


def pg_json(sql):
    """Ejecuta SQL en popelis-db y devuelve list[dict] (via json_agg)."""
    wrapped = f"SELECT COALESCE(json_agg(t), '[]') FROM ({sql}) t"
    out = subprocess.check_output(
        ["docker", "exec", PG_CONTAINER, "psql", "-U", PG_USER, "-d", PG_DB,
         "-tAc", wrapped], text=True)
    return json.loads(out.strip() or "[]")


def ch_query(sql):
    url = f"{CH_URL}/?{urllib.parse.urlencode({'database': CH_DB, 'default_format': 'JSONEachRow'})}"
    req = urllib.request.Request(url, data=sql.encode(),
                                 headers={"X-ClickHouse-User": CH_USER, "X-ClickHouse-Key": CH_PASS})
    with urllib.request.urlopen(req, timeout=30) as r:
        body = r.read().decode()
    return [json.loads(l) for l in body.splitlines() if l.strip()]


def ch_insert(table, rows):
    if not rows:
        return 0
    body = "\n".join(json.dumps(r, separators=(",", ":")) for r in rows).encode()
    q = f"INSERT INTO {CH_DB}.{table} FORMAT JSONEachRow"
    url = f"{CH_URL}/?{urllib.parse.urlencode({'database': CH_DB, 'query': q})}"
    req = urllib.request.Request(url, data=body,
                                 headers={"X-ClickHouse-User": CH_USER, "X-ClickHouse-Key": CH_PASS,
                                          "Content-Type": "text/plain"})
    try:
        urllib.request.urlopen(req, timeout=30).read()
    except urllib.error.HTTPError as e:
        raise ValueError(f"CH {e.code}: {e.read()[:300]}")
    return len(rows)


def fmt_ts(s):
    if not s:
        return "1970-01-01 00:00:00"
    return str(s).replace("T", " ").split(".")[0].split("+")[0][:19]


def main():
    total = 0
    # users (snapshot)
    users = pg_json("SELECT id AS user_id, username, jf_user_id, "
                    "to_char(COALESCE(created_at, now()),'YYYY-MM-DD HH24:MI:SS') AS created_at "
                    "FROM users") if has_col("users", "created_at") else \
        pg_json("SELECT id AS user_id, username, jf_user_id FROM users")
    for u in users:
        u["snapshot_ts"] = SNAP
        u.setdefault("created_at", "1970-01-01 00:00:00")
        u["created_at"] = fmt_ts(u["created_at"])
    total += ch_insert("popelis_users", users)

    # mylist (snapshot)
    ml = pg_json("SELECT user_id, item_id, "
                 "to_char(COALESCE(added_at, now()),'YYYY-MM-DD HH24:MI:SS') AS added_at FROM mylist") \
        if has_col("mylist", "added_at") else \
        pg_json("SELECT user_id, item_id FROM mylist")
    for m in ml:
        m["snapshot_ts"] = SNAP
        m.setdefault("added_at", "1970-01-01 00:00:00")
        m["added_at"] = fmt_ts(m["added_at"])
    total += ch_insert("popelis_mylist", ml)

    # events (incremental por id)
    last = 0
    try:
        r = ch_query("SELECT max(event_id) AS m FROM popelis_events")
        last = int(r[0]["m"]) if r and r[0].get("m") not in (None, "") else 0
    except Exception:
        last = 0
    ev = pg_json(f"SELECT id AS event_id, "
                 f"to_char(ts,'YYYY-MM-DD HH24:MI:SS') AS event_ts, "
                 f"COALESCE(user_id,0) AS user_id, username, event_type, item_id, meta "
                 f"FROM events WHERE id > {last} ORDER BY id")
    for e in ev:
        e["event_ts"] = fmt_ts(e["event_ts"])
    total += ch_insert("popelis_events", ev)

    print(json.dumps({"snapshot_ts": SNAP, "users": len(users), "mylist": len(ml),
                      "events_new": len(ev), "inserted": total}))


def has_col(table, col):
    try:
        out = subprocess.check_output(
            ["docker", "exec", PG_CONTAINER, "psql", "-U", PG_USER, "-d", PG_DB, "-tAc",
             f"SELECT 1 FROM information_schema.columns WHERE table_name='{table}' AND column_name='{col}'"],
            text=True).strip()
        return out == "1"
    except Exception:
        return False


if __name__ == "__main__":
    main()