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

    # Ensure TNS_ADMIN is set as OS env var so oracledb can find tnsnames.ora
    if settings.TNS_ADMIN:
        os.environ['TNS_ADMIN'] = settings.TNS_ADMIN

    logger.info(f"Oracle config: DSN={dsn}, TNS_ADMIN={settings.TNS_ADMIN or os.environ.get('TNS_ADMIN', '(not set)')}, INSTANTCLIENTPATH={instantclient_path or '(not set)'}")

    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,
    error_message   TEXT,
    already_imported INTEGER DEFAULT 0,
    new_imported     INTEGER DEFAULT 0
);

CREATE TABLE IF NOT EXISTS orders (
    order_number          TEXT PRIMARY KEY,
    order_date            TEXT,
    customer_name         TEXT,
    status                TEXT,
    id_comanda            INTEGER,
    id_partener           INTEGER,
    id_adresa_facturare   INTEGER,
    id_adresa_livrare     INTEGER,
    error_message         TEXT,
    missing_skus          TEXT,
    items_count           INTEGER,
    times_skipped         INTEGER DEFAULT 0,
    first_seen_at         TEXT DEFAULT (datetime('now')),
    last_sync_run_id      TEXT REFERENCES sync_runs(run_id),
    updated_at            TEXT DEFAULT (datetime('now')),
    shipping_name         TEXT,
    billing_name          TEXT,
    payment_method        TEXT,
    delivery_method       TEXT,
    factura_serie         TEXT,
    factura_numar         TEXT,
    factura_total_fara_tva REAL,
    factura_total_tva     REAL,
    factura_total_cu_tva  REAL,
    factura_data          TEXT,
    invoice_checked_at    TEXT,
    order_total           REAL,
    delivery_cost         REAL,
    discount_total        REAL,
    web_status          TEXT
);
CREATE INDEX IF NOT EXISTS idx_orders_status ON orders(status);
CREATE INDEX IF NOT EXISTS idx_orders_date ON orders(order_date);

CREATE TABLE IF NOT EXISTS sync_run_orders (
    sync_run_id    TEXT REFERENCES sync_runs(run_id),
    order_number   TEXT REFERENCES orders(order_number),
    status_at_run  TEXT,
    PRIMARY KEY (sync_run_id, order_number)
);

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
);

CREATE TABLE IF NOT EXISTS web_products (
    sku             TEXT PRIMARY KEY,
    product_name    TEXT,
    first_seen      TEXT DEFAULT (datetime('now')),
    last_seen       TEXT DEFAULT (datetime('now')),
    order_count     INTEGER DEFAULT 0
);

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

CREATE TABLE IF NOT EXISTS order_items (
    order_number   TEXT,
    sku            TEXT,
    product_name   TEXT,
    quantity       REAL,
    price          REAL,
    vat            REAL,
    mapping_status TEXT,
    codmat         TEXT,
    id_articol     INTEGER,
    cantitate_roa  REAL,
    created_at     TEXT DEFAULT (datetime('now')),
    PRIMARY KEY (order_number, sku)
);
CREATE INDEX IF NOT EXISTS idx_order_items_order ON order_items(order_number);
"""

_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)

    # Check existing tables before running schema
    cursor = conn.execute("SELECT name FROM sqlite_master WHERE type='table'")
    existing_tables = {row[0] for row in cursor.fetchall()}

    # Migration: import_orders → orders (one row per order)
    if 'import_orders' in existing_tables and 'orders' not in existing_tables:
        logger.info("Migrating import_orders → orders schema...")
        conn.executescript("""
            CREATE TABLE orders (
                order_number          TEXT PRIMARY KEY,
                order_date            TEXT,
                customer_name         TEXT,
                status                TEXT,
                id_comanda            INTEGER,
                id_partener           INTEGER,
                id_adresa_facturare   INTEGER,
                id_adresa_livrare     INTEGER,
                error_message         TEXT,
                missing_skus          TEXT,
                items_count           INTEGER,
                times_skipped         INTEGER DEFAULT 0,
                first_seen_at         TEXT DEFAULT (datetime('now')),
                last_sync_run_id      TEXT,
                updated_at            TEXT DEFAULT (datetime('now'))
            );
            CREATE INDEX IF NOT EXISTS idx_orders_status ON orders(status);
            CREATE INDEX IF NOT EXISTS idx_orders_date ON orders(order_date);

            CREATE TABLE sync_run_orders (
                sync_run_id    TEXT,
                order_number   TEXT,
                status_at_run  TEXT,
                PRIMARY KEY (sync_run_id, order_number)
            );
        """)
        # Copy latest record per order_number into orders
        # Note: old import_orders didn't have address columns — those stay NULL
        conn.execute("""
            INSERT INTO orders
                (order_number, order_date, customer_name, status,
                 id_comanda, id_partener, error_message, missing_skus,
                 items_count, last_sync_run_id)
            SELECT io.order_number, io.order_date, io.customer_name, io.status,
                   io.id_comanda, io.id_partener, io.error_message, io.missing_skus,
                   io.items_count, io.sync_run_id
            FROM import_orders io
            INNER JOIN (
                SELECT order_number, MAX(id) as max_id
                FROM import_orders
                GROUP BY order_number
            ) latest ON io.id = latest.max_id
        """)
        # Populate sync_run_orders from all import_orders rows
        conn.execute("""
            INSERT OR IGNORE INTO sync_run_orders (sync_run_id, order_number, status_at_run)
            SELECT sync_run_id, order_number, status
            FROM import_orders
            WHERE sync_run_id IS NOT NULL
        """)
        # Migrate order_items: drop sync_run_id, change PK to (order_number, sku)
        if 'order_items' in existing_tables:
            conn.executescript("""
                CREATE TABLE order_items_new (
                    order_number   TEXT,
                    sku            TEXT,
                    product_name   TEXT,
                    quantity       REAL,
                    price          REAL,
                    vat            REAL,
                    mapping_status TEXT,
                    codmat         TEXT,
                    id_articol     INTEGER,
                    cantitate_roa  REAL,
                    created_at     TEXT DEFAULT (datetime('now')),
                    PRIMARY KEY (order_number, sku)
                );
                INSERT OR IGNORE INTO order_items_new
                    (order_number, sku, product_name, quantity, price, vat,
                     mapping_status, codmat, id_articol, cantitate_roa, created_at)
                SELECT order_number, sku, product_name, quantity, price, vat,
                       mapping_status, codmat, id_articol, cantitate_roa, created_at
                FROM order_items;
                DROP TABLE order_items;
                ALTER TABLE order_items_new RENAME TO order_items;
                CREATE INDEX IF NOT EXISTS idx_order_items_order ON order_items(order_number);
            """)
        # Rename old table instead of dropping (safety backup)
        conn.execute("ALTER TABLE import_orders RENAME TO import_orders_bak")
        conn.commit()
        logger.info("Migration complete: import_orders → orders")

    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}")
        # Migrate sync_runs: add columns
        cursor = conn.execute("PRAGMA table_info(sync_runs)")
        sync_cols = {row[1] for row in cursor.fetchall()}
        if "error_message" not in sync_cols:
            conn.execute("ALTER TABLE sync_runs ADD COLUMN error_message TEXT")
            logger.info("Migrated sync_runs: added column error_message")
        if "already_imported" not in sync_cols:
            conn.execute("ALTER TABLE sync_runs ADD COLUMN already_imported INTEGER DEFAULT 0")
            logger.info("Migrated sync_runs: added column already_imported")
        if "new_imported" not in sync_cols:
            conn.execute("ALTER TABLE sync_runs ADD COLUMN new_imported INTEGER DEFAULT 0")
            logger.info("Migrated sync_runs: added column new_imported")

        # Migrate orders: add shipping/billing/payment/delivery + invoice columns
        cursor = conn.execute("PRAGMA table_info(orders)")
        order_cols = {row[1] for row in cursor.fetchall()}
        for col, typedef in [
            ("shipping_name", "TEXT"),
            ("billing_name", "TEXT"),
            ("payment_method", "TEXT"),
            ("delivery_method", "TEXT"),
            ("factura_serie", "TEXT"),
            ("factura_numar", "TEXT"),
            ("factura_total_fara_tva", "REAL"),
            ("factura_total_tva", "REAL"),
            ("factura_total_cu_tva", "REAL"),
            ("factura_data", "TEXT"),
            ("invoice_checked_at", "TEXT"),
            ("order_total", "REAL"),
            ("delivery_cost", "REAL"),
            ("discount_total", "REAL"),
            ("web_status", "TEXT"),
        ]:
            if col not in order_cols:
                conn.execute(f"ALTER TABLE orders ADD COLUMN {col} {typedef}")
                logger.info(f"Migrated orders: 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