"""Alembic env.py -- read DB URL from ZCBOT_DB_URL, metadata from core.storage.models."""
from __future__ import annotations

import os
import sys
from logging.config import fileConfig
from pathlib import Path

from alembic import context
from sqlalchemy import engine_from_config, pool

# Make project root importable so we can pull in core.storage.models
ROOT = Path(__file__).resolve().parent.parent.parent
sys.path.insert(0, str(ROOT))

from core.storage.models import Base  # noqa: E402

config = context.config

if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# Inject URL from env var (not hardcoded in alembic.ini)
db_url = os.environ.get("ZCBOT_DB_URL", "").strip()
if not db_url:
    raise RuntimeError(
        "ZCBOT_DB_URL is not set.\n"
        "  export ZCBOT_DB_URL='postgresql+psycopg://user:pass@host:5432/dbname'"
    )
config.set_main_option("sqlalchemy.url", db_url)

target_metadata = Base.metadata


def run_migrations_offline() -> None:
    context.configure(
        url=db_url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )
    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online() -> None:
    connectable = engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )
    with connectable.connect() as connection:
        context.configure(connection=connection, target_metadata=target_metadata)
        with context.begin_transaction():
            context.run_migrations()


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()
