"""
run_migrations.py — Idempotent SQL migration runner for Docker init.
Uses psql (not psycopg2) so each statement runs independently —
one error doesn't roll back the entire file.
"""

import os
import subprocess
import sys

import psycopg2

DATABASE_URL = os.environ["DATABASE_URL"]

MIGRATIONS = [
    "02_tracksolid_full_schema_rev.sql",
    "03_webhook_schema_migration.sql",
]

CRITICAL_TABLES = [
    "tracksolid.devices",
    "tracksolid.api_token_cache",
    "tracksolid.ingestion_log",
    "tracksolid.live_positions",
    "tracksolid.position_history",
    "tracksolid.trips",
    "tracksolid.alarms",
    "tracksolid.obd_readings",
]


def run_file(path, filename):
    """Execute a SQL file via psql. Returns True on success."""
    print(f"Running {filename}...")
    result = subprocess.run(
        ["psql", DATABASE_URL, "-f", path],
        capture_output=True, text=True,
    )
    # psql prints errors to stderr but continues by default
    errors = [l for l in result.stderr.splitlines() if "ERROR:" in l]
    if errors:
        for e in errors:
            print(f"  WARN: {e.strip()}")
        return False
    print(f"  OK: {filename}")
    return True


def verify_schema():
    """Verify critical tables exist. Exit 1 if not — prevents services from starting."""
    print("Verifying schema...")
    conn = psycopg2.connect(DATABASE_URL)
    cur = conn.cursor()
    missing = []
    for table in CRITICAL_TABLES:
        schema, name = table.split(".")
        cur.execute(
            "SELECT 1 FROM information_schema.tables WHERE table_schema=%s AND table_name=%s",
            (schema, name),
        )
        if not cur.fetchone():
            missing.append(table)
    cur.close()
    conn.close()

    if missing:
        print(f"FATAL: Missing critical tables: {', '.join(missing)}")
        print("Schema bootstrap failed. Services cannot start.")
        sys.exit(1)
    print("  All critical tables verified.")


def main():
    print("=== Database Migration Runner ===")

    for sql_file in MIGRATIONS:
        path = os.path.join("/app", sql_file)
        if not os.path.exists(path):
            print(f"  SKIP: {sql_file} (not found)")
            continue
        run_file(path, sql_file)

    verify_schema()
    print("Migrations complete.")


if __name__ == "__main__":
    main()