"""Migration automatique SQLite — détecte et ajoute les colonnes manquantes."""
import logging
from sqlalchemy import text
from app.database import engine

logger = logging.getLogger(__name__)

# Définition des colonnes attendues par table : {table: [(col, type_sql, default)]}
EXPECTED_COLUMNS: dict[str, list[tuple[str, str, str | None]]] = {
    "plant": [
        ("categorie", "TEXT", None),
        ("hauteur_cm", "INTEGER", None),
        ("maladies_courantes", "TEXT", None),
        ("astuces_culture", "TEXT", None),
        ("url_reference", "TEXT", None),
    ],
    "garden": [
        ("surface_m2", "REAL", None),
        ("ensoleillement", "TEXT", None),
    ],
    "task": [
        ("frequence_jours", "INTEGER", None),
        ("date_prochaine", "TEXT", None),
        ("outil_id", "INTEGER", None),
    ],
    "plantvariety": [
        # ancien nom de table → migration vers "plant" si présente
    ],
    "media": [
        ("identified_species", "TEXT", None),
        ("identified_common", "TEXT", None),
        ("identified_confidence", "REAL", None),
        ("identified_source", "TEXT", None),
    ],
}


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


def _existing_tables(conn) -> set[str]:
    rows = conn.execute(text("SELECT name FROM sqlite_master WHERE type='table'")).fetchall()
    return {row[0] for row in rows}


def run_migrations() -> None:
    with engine.connect() as conn:
        tables = _existing_tables(conn)

        # Renommage plantvariety → plant si l'ancienne table existe et la nouvelle non
        if "plantvariety" in tables and "plant" not in tables:
            conn.execute(text("ALTER TABLE plantvariety RENAME TO plant"))
            conn.commit()
            logger.info("Migration: plantvariety renommée en plant")
            tables = _existing_tables(conn)

        for table, columns in EXPECTED_COLUMNS.items():
            if table not in tables or not columns:
                continue
            existing = _existing_columns(conn, table)
            for col_name, col_type, default in columns:
                if col_name not in existing:
                    if default is not None:
                        sql = f"ALTER TABLE {table} ADD COLUMN {col_name} {col_type} DEFAULT {default}"
                    else:
                        sql = f"ALTER TABLE {table} ADD COLUMN {col_name} {col_type}"
                    conn.execute(text(sql))
                    conn.commit()
                    logger.info(f"Migration: colonne {table}.{col_name} ajoutée")