"""One-time (idempotent) seed of Postgres from the existing Google Sheets.

This is the ONLY place the Sheet is treated as authoritative — to bootstrap the
DB. After this, Postgres is the source of truth and Sheets is a downstream
mirror. Safe to re-run: keyed tables upsert by primary key; activity_log is
replaced wholesale.

Run inside the container:  docker compose exec smb-crm python import_from_sheets.py
"""
import os
import sys

import db
from sheets import Sheets


def upsert(cur, entity, records):
    spec = db.TABLES[entity]
    cols = spec["cols"]
    pk = spec["pk"]
    n = 0
    for rec in records:
        row = db.coerce_row(entity, rec)
        if entity != "activity_log" and not row.get(pk):
            continue  # skip rows without a primary key
        placeholders = ", ".join(["%s"] * len(cols))
        collist = ", ".join(cols)
        if entity == "activity_log":
            cur.execute(f"INSERT INTO {entity} ({collist}) VALUES ({placeholders})",
                        [row[c] for c in cols])
        else:
            updates = ", ".join(f"{c} = EXCLUDED.{c}" for c in cols if c != pk)
            cur.execute(
                f"INSERT INTO {entity} ({collist}) VALUES ({placeholders}) "
                f"ON CONFLICT ({pk}) DO UPDATE SET {updates}",
                [row[c] for c in cols])
        n += 1
    return n


def main():
    sh = Sheets(os.environ["GOOGLE_SA_JSON"], os.environ["SHEET_ID"])
    with db.connect() as conn:
        with conn.cursor() as cur:
            cur.execute("TRUNCATE activity_log RESTART IDENTITY")
            for entity, spec in db.TABLES.items():
                records = sh.read_records(spec["tab"])
                n = upsert(cur, entity, records)
                print(f"  {entity:<13} <- {spec['tab']:<13} {n} row(s)")
        conn.commit()
    print("import complete.")


if __name__ == "__main__":
    sys.exit(main())