import oracledb
import aiosqlite
import sqlite3
import logging
import os
from pathlib import Path
from .config import settings

logger = logging.getLogger(__name__)

# ---- Oracle Pool ----
pool = None

def init_oracle():
    """Initialize Oracle client mode and create connection pool."""
    global pool

    force_thin = settings.FORCE_THIN_MODE
    instantclient_path = settings.INSTANTCLIENTPATH
    dsn = settings.ORACLE_DSN

    if force_thin:
        logger.info(f"FORCE_THIN_MODE=true: thin mode for {dsn}")
    elif instantclient_path:
        try:
            oracledb.init_oracle_client(lib_dir=instantclient_path)
            logger.info(f"Thick mode activated for {dsn}")
        except Exception as e:
            logger.error(f"Thick mode error: {e}")
            logger.info("Fallback to thin mode")
    else:
        logger.info(f"Thin mode (default) for {dsn}")

    pool = oracledb.create_pool(
        user=settings.ORACLE_USER,
        password=settings.ORACLE_PASSWORD,
        dsn=settings.ORACLE_DSN,
        min=2,
        max=4,
        increment=1
    )
    logger.info(f"Oracle pool created for {dsn}")
    return pool

def get_oracle_connection():
    """Get a connection from the Oracle pool."""
    if pool is None:
        raise RuntimeError("Oracle pool not initialized")
    return pool.acquire()

def close_oracle():
    """Close the Oracle connection pool."""
    global pool
    if pool:
        pool.close()
        pool = None
        logger.info("Oracle pool closed")

# ---- SQLite ----
SQLITE_SCHEMA = """
CREATE TABLE IF NOT EXISTS sync_runs (
    id          INTEGER PRIMARY KEY AUTOINCREMENT,
    run_id      TEXT UNIQUE,
    started_at  TEXT,
    finished_at TEXT,
    status      TEXT,
    total_orders    INTEGER DEFAULT 0,
    imported        INTEGER DEFAULT 0,
    skipped         INTEGER DEFAULT 0,
    errors          INTEGER DEFAULT 0,
    json_files      INTEGER DEFAULT 0
);

CREATE TABLE IF NOT EXISTS import_orders (
    id              INTEGER PRIMARY KEY AUTOINCREMENT,
    sync_run_id     TEXT REFERENCES sync_runs(run_id),
    order_number    TEXT,
    order_date      TEXT,
    customer_name   TEXT,
    status          TEXT,
    id_comanda      INTEGER,
    id_partener     INTEGER,
    error_message   TEXT,
    missing_skus    TEXT,
    items_count     INTEGER,
    created_at      TEXT DEFAULT (datetime('now'))
);

CREATE TABLE IF NOT EXISTS missing_skus (
    sku             TEXT PRIMARY KEY,
    product_name    TEXT,
    first_seen      TEXT DEFAULT (datetime('now')),
    resolved        INTEGER DEFAULT 0,
    resolved_at     TEXT,
    order_count     INTEGER DEFAULT 0,
    order_numbers   TEXT,
    customers       TEXT
);

CREATE TABLE IF NOT EXISTS scheduler_config (
    key             TEXT PRIMARY KEY,
    value           TEXT
);
"""

_sqlite_db_path = None

def init_sqlite():
    """Initialize SQLite database with schema."""
    global _sqlite_db_path
    _sqlite_db_path = settings.SQLITE_DB_PATH

    # Ensure directory exists
    db_dir = os.path.dirname(_sqlite_db_path)
    if db_dir:
        os.makedirs(db_dir, exist_ok=True)

    # Create tables synchronously
    conn = sqlite3.connect(_sqlite_db_path)
    conn.executescript(SQLITE_SCHEMA)

    # Migrate: add columns if missing (for existing databases)
    try:
        cursor = conn.execute("PRAGMA table_info(missing_skus)")
        cols = {row[1] for row in cursor.fetchall()}
        for col, typedef in [("order_count", "INTEGER DEFAULT 0"),
                             ("order_numbers", "TEXT"),
                             ("customers", "TEXT")]:
            if col not in cols:
                conn.execute(f"ALTER TABLE missing_skus ADD COLUMN {col} {typedef}")
                logger.info(f"Migrated missing_skus: added column {col}")
        conn.commit()
    except Exception as e:
        logger.warning(f"Migration check failed: {e}")

    conn.close()
    logger.info(f"SQLite initialized: {_sqlite_db_path}")

async def get_sqlite():
    """Get async SQLite connection."""
    if _sqlite_db_path is None:
        raise RuntimeError("SQLite not initialized")
    db = await aiosqlite.connect(_sqlite_db_path)
    db.row_factory = aiosqlite.Row
    return db

def get_sqlite_sync():
    """Get synchronous SQLite connection."""
    if _sqlite_db_path is None:
        raise RuntimeError("SQLite not initialized")
    conn = sqlite3.connect(_sqlite_db_path)
    conn.row_factory = sqlite3.Row
    return conn