"""Leichte In-Place-Migrationen für SQLite (kein Alembic).

Wird beim App-Start nach create_all() ausgeführt. Idempotent.
"""
from __future__ import annotations

import logging

from sqlalchemy import text
from sqlmodel import Session

from app.core.db import engine

log = logging.getLogger("voice-agent.migrate")


def _existing_columns(conn, table: str) -> set[str]:
    rows = conn.execute(text(f"PRAGMA table_info({table})")).all()
    return {r[1] for r in rows}  # row[1] = column name


def run_migrations() -> None:
    with engine.begin() as conn:
        # 1) Job.owner_id Spalte nachrüsten, falls die Tabelle aus alter Version kommt.
        cols = _existing_columns(conn, "job")
        if "owner_id" not in cols:
            log.info("Migration: füge job.owner_id hinzu")
            conn.execute(text("ALTER TABLE job ADD COLUMN owner_id INTEGER"))
            conn.execute(text("CREATE INDEX IF NOT EXISTS ix_job_owner_id ON job(owner_id)"))

        # 2) Job.profile Spalte nachrüsten (Profil-System).
        cols = _existing_columns(conn, "job")
        if "profile" not in cols:
            log.info("Migration: füge job.profile hinzu (default 'meeting')")
            conn.execute(text("ALTER TABLE job ADD COLUMN profile VARCHAR DEFAULT 'meeting'"))

        # 3) User.default_profile nachrüsten.
        user_cols = _existing_columns(conn, "user")
        if user_cols and "default_profile" not in user_cols:
            log.info("Migration: füge user.default_profile hinzu (default 'meeting')")
            conn.execute(text("ALTER TABLE user ADD COLUMN default_profile VARCHAR DEFAULT 'meeting'"))

        # 4) Job.pdf_path nachrüsten (PDF-Export zusätzlich zu DOCX).
        cols = _existing_columns(conn, "job")
        if "pdf_path" not in cols:
            log.info("Migration: füge job.pdf_path hinzu")
            conn.execute(text("ALTER TABLE job ADD COLUMN pdf_path VARCHAR DEFAULT ''"))

        # 5) Diagnose-Felder: step_started_at, last_heartbeat_at
        cols = _existing_columns(conn, "job")
        if "step_started_at" not in cols:
            log.info("Migration: füge job.step_started_at hinzu")
            conn.execute(text("ALTER TABLE job ADD COLUMN step_started_at DATETIME"))
        if "last_heartbeat_at" not in cols:
            log.info("Migration: füge job.last_heartbeat_at hinzu")
            conn.execute(text("ALTER TABLE job ADD COLUMN last_heartbeat_at DATETIME"))

        # 6) Modell-Auswahl: user.default_model + job.model
        user_cols = _existing_columns(conn, "user")
        if user_cols and "default_model" not in user_cols:
            log.info("Migration: füge user.default_model hinzu (leer = Worker-Default)")
            conn.execute(text("ALTER TABLE user ADD COLUMN default_model VARCHAR DEFAULT ''"))
        cols = _existing_columns(conn, "job")
        if "model" not in cols:
            log.info("Migration: füge job.model hinzu (leer = Worker-Default)")
            conn.execute(text("ALTER TABLE job ADD COLUMN model VARCHAR DEFAULT ''"))


def assign_orphan_jobs_to(user_id: int) -> int:
    """Weist alle Jobs ohne owner_id dem angegebenen User zu. Gibt Anzahl zurück."""
    with Session(engine) as session:
        result = session.execute(
            text("UPDATE job SET owner_id = :uid WHERE owner_id IS NULL"),
            {"uid": user_id},
        )
        session.commit()
        n = result.rowcount or 0
        if n:
            log.info("Migration: %d Bestand-Jobs an user_id=%d zugeordnet", n, user_id)
        return n