import logging
from .. import database

logger = logging.getLogger(__name__)

def check_orders_in_roa(min_date, conn) -> dict:
    """Check which orders already exist in Oracle COMENZI by date range.
    Returns: {comanda_externa: id_comanda} for all existing orders.
    Much faster than IN-clause batching — single query using date index.
    """
    if conn is None:
        return {}

    existing = {}
    try:
        with conn.cursor() as cur:
            cur.execute("""
                SELECT comanda_externa, id_comanda FROM COMENZI
                WHERE data_comanda >= :min_date
                  AND comanda_externa IS NOT NULL AND sters = 0
            """, {"min_date": min_date})
            for row in cur:
                existing[str(row[0])] = row[1]
    except Exception as e:
        logger.error(f"check_orders_in_roa failed: {e}")

    logger.info(f"ROA order check (since {min_date}): {len(existing)} existing orders found")
    return existing


def resolve_codmat_ids(codmats: set[str], id_gestiuni: list[int] = None, conn=None) -> dict[str, dict]:
    """Resolve CODMATs to best id_articol + cont: prefers article with stock, then MAX(id_articol).
    Filters: sters=0 AND inactiv=0.
    id_gestiuni: list of warehouse IDs to check stock in, or None for all.
    Returns: {codmat: {"id_articol": int, "cont": str|None}}
    """
    if not codmats:
        return {}

    result = {}
    codmat_list = list(codmats)

    # Build stoc subquery dynamically for index optimization
    if id_gestiuni:
        gest_placeholders = ",".join([f":g{k}" for k in range(len(id_gestiuni))])
        stoc_filter = f"AND s.id_gestiune IN ({gest_placeholders})"
    else:
        stoc_filter = ""

    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        with conn.cursor() as cur:
            for i in range(0, len(codmat_list), 500):
                batch = codmat_list[i:i+500]
                placeholders = ",".join([f":c{j}" for j in range(len(batch))])
                params = {f"c{j}": cm for j, cm in enumerate(batch)}
                if id_gestiuni:
                    for k, gid in enumerate(id_gestiuni):
                        params[f"g{k}"] = gid

                cur.execute(f"""
                    SELECT codmat, id_articol, cont FROM (
                        SELECT na.codmat, na.id_articol, na.cont,
                               ROW_NUMBER() OVER (
                                   PARTITION BY na.codmat
                                   ORDER BY
                                       CASE WHEN EXISTS (
                                           SELECT 1 FROM stoc s
                                           WHERE s.id_articol = na.id_articol
                                             {stoc_filter}
                                             AND s.an = EXTRACT(YEAR FROM SYSDATE)
                                             AND s.luna = EXTRACT(MONTH FROM SYSDATE)
                                             AND s.cants + s.cant - s.cante > 0
                                       ) THEN 0 ELSE 1 END,
                                       na.id_articol DESC
                               ) AS rn
                          FROM nom_articole na
                         WHERE na.codmat IN ({placeholders})
                           AND na.sters = 0 AND na.inactiv = 0
                    ) WHERE rn = 1
                """, params)
                for row in cur:
                    result[row[0]] = {"id_articol": row[1], "cont": row[2]}
    finally:
        if own_conn:
            database.pool.release(conn)

    logger.info(f"resolve_codmat_ids: {len(result)}/{len(codmats)} resolved (gestiuni={id_gestiuni})")
    return result


def validate_skus(skus: set[str], conn=None, id_gestiuni: list[int] = None) -> dict:
    """Validate a set of SKUs against Oracle.
    Returns: {mapped: set, direct: set, missing: set, direct_id_map: {codmat: {"id_articol": int, "cont": str|None}}}
    - mapped: found in ARTICOLE_TERTI (active)
    - direct: found in NOM_ARTICOLE by codmat (not in ARTICOLE_TERTI)
    - missing: not found anywhere
    - direct_id_map: {codmat: {"id_articol": int, "cont": str|None}} for direct SKUs
    """
    if not skus:
        return {"mapped": set(), "direct": set(), "missing": set(), "direct_id_map": {}}

    mapped = set()
    sku_list = list(skus)

    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        with conn.cursor() as cur:
            # Check in batches of 500
            for i in range(0, len(sku_list), 500):
                batch = sku_list[i:i+500]
                placeholders = ",".join([f":s{j}" for j in range(len(batch))])
                params = {f"s{j}": sku for j, sku in enumerate(batch)}

                # Check ARTICOLE_TERTI
                cur.execute(f"""
                    SELECT DISTINCT sku FROM ARTICOLE_TERTI
                    WHERE sku IN ({placeholders}) AND activ = 1 AND sters = 0
                """, params)
                for row in cur:
                    mapped.add(row[0])

        # Resolve remaining SKUs via resolve_codmat_ids (consistent id_articol selection)
        all_remaining = [s for s in sku_list if s not in mapped]
        if all_remaining:
            direct_id_map = resolve_codmat_ids(set(all_remaining), id_gestiuni, conn)
            direct = set(direct_id_map.keys())
        else:
            direct_id_map = {}
            direct = set()

    finally:
        if own_conn:
            database.pool.release(conn)

    missing = skus - mapped - direct

    logger.info(f"SKU validation: {len(mapped)} mapped, {len(direct)} direct, {len(missing)} missing")
    return {"mapped": mapped, "direct": direct, "missing": missing,
            "direct_id_map": direct_id_map}

def classify_orders(orders, validation_result):
    """Classify orders as importable or skipped based on SKU validation.
    Returns: (importable_orders, skipped_orders)
    Each skipped entry is a tuple of (order, list_of_missing_skus).
    """
    ok_skus = validation_result["mapped"] | validation_result["direct"]
    importable = []
    skipped = []

    for order in orders:
        order_skus = {item.sku for item in order.items if item.sku}
        order_missing = order_skus - ok_skus

        if order_missing:
            skipped.append((order, list(order_missing)))
        else:
            importable.append(order)

    return importable, skipped

def _extract_id_map(direct_id_map: dict) -> dict:
    """Extract {codmat: id_articol} from either enriched or simple format."""
    if not direct_id_map:
        return {}
    result = {}
    for cm, val in direct_id_map.items():
        if isinstance(val, dict):
            result[cm] = val["id_articol"]
        else:
            result[cm] = val
    return result


def validate_prices(codmats: set[str], id_pol: int, conn=None, direct_id_map: dict=None) -> dict:
    """Check which CODMATs have a price entry in CRM_POLITICI_PRET_ART for the given policy.
    If direct_id_map is provided, skips the NOM_ARTICOLE lookup for those CODMATs.
    Returns: {"has_price": set_of_codmats, "missing_price": set_of_codmats}
    """
    if not codmats:
        return {"has_price": set(), "missing_price": set()}

    codmat_to_id = _extract_id_map(direct_id_map)
    ids_with_price = set()

    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        with conn.cursor() as cur:
            # Check which ID_ARTICOLs have a price in the policy
            id_list = list(codmat_to_id.values())
            for i in range(0, len(id_list), 500):
                batch = id_list[i:i+500]
                placeholders = ",".join([f":a{j}" for j in range(len(batch))])
                params = {f"a{j}": aid for j, aid in enumerate(batch)}
                params["id_pol"] = id_pol

                cur.execute(f"""
                    SELECT DISTINCT pa.ID_ARTICOL FROM CRM_POLITICI_PRET_ART pa
                    WHERE pa.ID_POL = :id_pol AND pa.ID_ARTICOL IN ({placeholders})
                """, params)
                for row in cur:
                    ids_with_price.add(row[0])
    finally:
        if own_conn:
            database.pool.release(conn)

    # Map back to CODMATs
    has_price = {cm for cm, aid in codmat_to_id.items() if aid in ids_with_price}
    missing_price = codmats - has_price

    logger.info(f"Price validation (policy {id_pol}): {len(has_price)} have price, {len(missing_price)} missing price")
    return {"has_price": has_price, "missing_price": missing_price}

def ensure_prices(codmats: set[str], id_pol: int, conn=None, direct_id_map: dict=None,
                   cota_tva: float = None):
    """Insert price 0 entries for CODMATs missing from the given price policy.
    Uses batch executemany instead of individual INSERTs.
    Relies on TRG_CRM_POLITICI_PRET_ART trigger for ID_POL_ART sequence.
    cota_tva: VAT rate from settings (e.g. 21) — used for PROC_TVAV metadata.
    """
    if not codmats:
        return

    proc_tvav = 1 + (cota_tva / 100) if cota_tva else 1.21

    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        with conn.cursor() as cur:
            # Get ID_VALUTA for this policy
            cur.execute("""
                SELECT ID_VALUTA FROM CRM_POLITICI_PRETURI WHERE ID_POL = :id_pol
            """, {"id_pol": id_pol})
            row = cur.fetchone()
            if not row:
                logger.error(f"Price policy {id_pol} not found in CRM_POLITICI_PRETURI")
                return
            id_valuta = row[0]

            # Build batch params using direct_id_map (already resolved via resolve_codmat_ids)
            batch_params = []
            codmat_id_map = _extract_id_map(direct_id_map)

            for codmat in codmats:
                id_articol = codmat_id_map.get(codmat)
                if not id_articol:
                    logger.warning(f"CODMAT {codmat} not found in NOM_ARTICOLE, skipping price insert")
                    continue
                batch_params.append({
                    "id_pol": id_pol,
                    "id_articol": id_articol,
                    "id_valuta": id_valuta,
                    "proc_tvav": proc_tvav
                })

            if batch_params:
                cur.executemany("""
                    INSERT INTO CRM_POLITICI_PRET_ART
                        (ID_POL, ID_ARTICOL, PRET, ID_VALUTA,
                         ID_UTIL, DATAORA, PROC_TVAV, PRETFTVA, PRETCTVA)
                    VALUES
                        (:id_pol, :id_articol, 0, :id_valuta,
                         -3, SYSDATE, :proc_tvav, 0, 0)
                """, batch_params)
                logger.info(f"Batch inserted {len(batch_params)} price entries for policy {id_pol} (PROC_TVAV={proc_tvav})")

            conn.commit()
    finally:
        if own_conn:
            database.pool.release(conn)

    logger.info(f"Ensure prices done: {len(codmats)} CODMATs processed for policy {id_pol}")


def validate_and_ensure_prices_dual(codmats: set[str], id_pol_vanzare: int,
                                     id_pol_productie: int, conn, direct_id_map: dict,
                                     cota_tva: float = 21) -> dict[str, int]:
    """Dual-policy price validation: assign each CODMAT to sales or production policy.

    Logic:
    1. Check both policies in one SQL
    2. If article in one policy → use that
    3. If article in BOTH → prefer id_pol_vanzare
    4. If article in NEITHER → check cont: 341/345 → production, else → sales; insert price 0

    Returns: codmat_policy_map = {codmat: assigned_id_pol}
    """
    if not codmats:
        return {}

    codmat_policy_map = {}
    id_map = _extract_id_map(direct_id_map)

    # Collect all id_articol values we need to check
    id_to_codmats = {}  # {id_articol: [codmat, ...]}
    for cm in codmats:
        aid = id_map.get(cm)
        if aid:
            id_to_codmats.setdefault(aid, []).append(cm)

    if not id_to_codmats:
        return {}

    # Query both policies in one SQL
    existing = {}  # {id_articol: set of id_pol}
    id_list = list(id_to_codmats.keys())
    with conn.cursor() as cur:
        for i in range(0, len(id_list), 500):
            batch = id_list[i:i+500]
            placeholders = ",".join([f":a{j}" for j in range(len(batch))])
            params = {f"a{j}": aid for j, aid in enumerate(batch)}
            params["id_pol_v"] = id_pol_vanzare
            params["id_pol_p"] = id_pol_productie

            cur.execute(f"""
                SELECT pa.ID_ARTICOL, pa.ID_POL FROM CRM_POLITICI_PRET_ART pa
                WHERE pa.ID_POL IN (:id_pol_v, :id_pol_p) AND pa.ID_ARTICOL IN ({placeholders})
            """, params)
            for row in cur:
                existing.setdefault(row[0], set()).add(row[1])

    # Classify each codmat
    missing_vanzare = set()   # CODMATs needing price 0 in sales policy
    missing_productie = set() # CODMATs needing price 0 in production policy

    for aid, cms in id_to_codmats.items():
        pols = existing.get(aid, set())
        for cm in cms:
            if pols:
                if id_pol_vanzare in pols:
                    codmat_policy_map[cm] = id_pol_vanzare
                elif id_pol_productie in pols:
                    codmat_policy_map[cm] = id_pol_productie
            else:
                # Not in any policy — classify by cont
                info = direct_id_map.get(cm, {})
                cont = info.get("cont", "") if isinstance(info, dict) else ""
                cont_str = str(cont or "").strip()
                if cont_str in ("341", "345"):
                    codmat_policy_map[cm] = id_pol_productie
                    missing_productie.add(cm)
                else:
                    codmat_policy_map[cm] = id_pol_vanzare
                    missing_vanzare.add(cm)

    # Ensure prices for missing articles in each policy
    if missing_vanzare:
        ensure_prices(missing_vanzare, id_pol_vanzare, conn, direct_id_map, cota_tva=cota_tva)
    if missing_productie:
        ensure_prices(missing_productie, id_pol_productie, conn, direct_id_map, cota_tva=cota_tva)

    logger.info(
        f"Dual-policy: {len(codmat_policy_map)} CODMATs assigned "
        f"(vanzare={sum(1 for v in codmat_policy_map.values() if v == id_pol_vanzare)}, "
        f"productie={sum(1 for v in codmat_policy_map.values() if v == id_pol_productie)})"
    )
    return codmat_policy_map


def resolve_mapped_codmats(mapped_skus: set[str], conn,
                           id_gestiuni: list[int] = None) -> dict[str, list[dict]]:
    """For mapped SKUs, get their underlying CODMATs from ARTICOLE_TERTI + nom_articole.

    Uses ROW_NUMBER to pick the best id_articol per (SKU, CODMAT) pair:
    prefers article with stock in current month, then MAX(id_articol) as fallback.
    This avoids inflating results when a CODMAT has multiple NOM_ARTICOLE entries.

    Returns: {sku: [{"codmat": str, "id_articol": int, "cont": str|None, "cantitate_roa": float|None}]}
    """
    if not mapped_skus:
        return {}

    # Build stoc subquery gestiune filter (same pattern as resolve_codmat_ids)
    if id_gestiuni:
        gest_placeholders = ",".join([f":g{k}" for k in range(len(id_gestiuni))])
        stoc_filter = f"AND s.id_gestiune IN ({gest_placeholders})"
    else:
        stoc_filter = ""

    result = {}
    sku_list = list(mapped_skus)

    with conn.cursor() as cur:
        for i in range(0, len(sku_list), 500):
            batch = sku_list[i:i+500]
            placeholders = ",".join([f":s{j}" for j in range(len(batch))])
            params = {f"s{j}": sku for j, sku in enumerate(batch)}
            if id_gestiuni:
                for k, gid in enumerate(id_gestiuni):
                    params[f"g{k}"] = gid

            cur.execute(f"""
                SELECT sku, codmat, id_articol, cont, cantitate_roa FROM (
                    SELECT at.sku, at.codmat, na.id_articol, na.cont, at.cantitate_roa,
                           ROW_NUMBER() OVER (
                               PARTITION BY at.sku, at.codmat
                               ORDER BY
                                   CASE WHEN EXISTS (
                                       SELECT 1 FROM stoc s
                                       WHERE s.id_articol = na.id_articol
                                         {stoc_filter}
                                         AND s.an = EXTRACT(YEAR FROM SYSDATE)
                                         AND s.luna = EXTRACT(MONTH FROM SYSDATE)
                                         AND s.cants + s.cant - s.cante > 0
                                   ) THEN 0 ELSE 1 END,
                                   na.id_articol DESC
                           ) AS rn
                    FROM ARTICOLE_TERTI at
                    JOIN NOM_ARTICOLE na ON na.codmat = at.codmat AND na.sters = 0 AND na.inactiv = 0
                    WHERE at.sku IN ({placeholders}) AND at.activ = 1 AND at.sters = 0
                ) WHERE rn = 1
            """, params)
            for row in cur:
                sku = row[0]
                if sku not in result:
                    result[sku] = []
                result[sku].append({
                    "codmat": row[1],
                    "id_articol": row[2],
                    "cont": row[3],
                    "cantitate_roa": row[4]
                })

    logger.info(f"resolve_mapped_codmats: {len(result)} SKUs → {sum(len(v) for v in result.values())} CODMATs")
    return result


def validate_kit_component_prices(mapped_codmat_data: dict, id_pol: int,
                                   id_pol_productie: int = None, conn=None) -> dict:
    """Pre-validate that kit components have non-zero prices in crm_politici_pret_art.

    Args:
        mapped_codmat_data: {sku: [{"codmat", "id_articol", "cont"}, ...]} from resolve_mapped_codmats
        id_pol: default sales price policy
        id_pol_productie: production price policy (for cont 341/345)

    Returns: {sku: [missing_codmats]} for SKUs with missing prices, {} if all OK
    """
    missing = {}
    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        with conn.cursor() as cur:
            for sku, components in mapped_codmat_data.items():
                if len(components) == 0:
                    continue
                if len(components) == 1 and (components[0].get("cantitate_roa") or 1) <= 1:
                    continue  # True 1:1 mapping, no kit pricing needed
                sku_missing = []
                for comp in components:
                    cont = str(comp.get("cont") or "").strip()
                    if cont in ("341", "345") and id_pol_productie:
                        pol = id_pol_productie
                    else:
                        pol = id_pol
                    cur.execute("""
                        SELECT PRET FROM crm_politici_pret_art
                        WHERE id_pol = :pol AND id_articol = :id_art
                    """, {"pol": pol, "id_art": comp["id_articol"]})
                    row = cur.fetchone()
                    if not row or (row[0] is not None and row[0] == 0):
                        sku_missing.append(comp["codmat"])
                if sku_missing:
                    missing[sku] = sku_missing
    finally:
        if own_conn:
            database.pool.release(conn)
    return missing


def compare_and_update_price(id_articol: int, id_pol: int, web_price_cu_tva: float,
                              conn, tolerance: float = 0.01) -> dict | None:
    """Compare web price with ROA price and update if different.

    Handles PRETURI_CU_TVA flag per policy.
    Returns: {"updated": bool, "old_price": float, "new_price": float, "codmat": str} or None if no price entry.
    """
    with conn.cursor() as cur:
        cur.execute("SELECT PRETURI_CU_TVA FROM CRM_POLITICI_PRETURI WHERE ID_POL = :pol", {"pol": id_pol})
        pol_row = cur.fetchone()
        if not pol_row:
            return None
        preturi_cu_tva = pol_row[0]  # 1 or 0

        cur.execute("""
            SELECT PRET, PROC_TVAV, na.codmat
            FROM crm_politici_pret_art pa
            JOIN nom_articole na ON na.id_articol = pa.id_articol
            WHERE pa.id_pol = :pol AND pa.id_articol = :id_art
        """, {"pol": id_pol, "id_art": id_articol})
        row = cur.fetchone()
        if not row:
            return None

        pret_roa, proc_tvav, codmat = row[0], row[1], row[2]
        proc_tvav = proc_tvav or 1.19

        if preturi_cu_tva == 1:
            pret_roa_cu_tva = pret_roa
        else:
            pret_roa_cu_tva = pret_roa * proc_tvav

        if abs(pret_roa_cu_tva - web_price_cu_tva) <= tolerance:
            return {"updated": False, "old_price": pret_roa_cu_tva, "new_price": web_price_cu_tva, "codmat": codmat}

        if preturi_cu_tva == 1:
            new_pret = web_price_cu_tva
        else:
            new_pret = round(web_price_cu_tva / proc_tvav, 4)

        cur.execute("""
            UPDATE crm_politici_pret_art SET PRET = :pret, DATAORA = SYSDATE
            WHERE id_pol = :pol AND id_articol = :id_art
        """, {"pret": new_pret, "pol": id_pol, "id_art": id_articol})
        conn.commit()

        return {"updated": True, "old_price": pret_roa_cu_tva, "new_price": web_price_cu_tva, "codmat": codmat}


def sync_prices_from_order(orders, mapped_codmat_data: dict, direct_id_map: dict,
                            codmat_policy_map: dict, id_pol: int,
                            id_pol_productie: int = None, conn=None,
                            settings: dict = None) -> list:
    """Sync prices from order items to ROA for direct/1:1 mappings.

    Skips kit components and transport/discount CODMATs.
    Returns: list of {"codmat", "old_price", "new_price"} for updated prices.
    """
    if settings and settings.get("price_sync_enabled") != "1":
        return []

    transport_codmat = (settings or {}).get("transport_codmat", "")
    discount_codmat = (settings or {}).get("discount_codmat", "")
    kit_discount_codmat = (settings or {}).get("kit_discount_codmat", "")
    skip_codmats = {transport_codmat, discount_codmat, kit_discount_codmat} - {""}

    # Build set of kit SKUs (>1 component)
    kit_skus = {sku for sku, comps in mapped_codmat_data.items() if len(comps) > 1}

    updated = []
    own_conn = conn is None
    if own_conn:
        conn = database.get_oracle_connection()
    try:
        for order in orders:
            for item in order.items:
                sku = item.sku
                if not sku or sku in skip_codmats:
                    continue
                if sku in kit_skus:
                    continue  # Don't sync prices from kit orders

                web_price = item.price  # already with TVA
                if not web_price or web_price <= 0:
                    continue

                # Determine id_articol and price policy for this SKU
                if sku in mapped_codmat_data and len(mapped_codmat_data[sku]) == 1:
                    # 1:1 mapping via ARTICOLE_TERTI
                    comp = mapped_codmat_data[sku][0]
                    id_articol = comp["id_articol"]
                    cantitate_roa = comp.get("cantitate_roa") or 1
                    web_price_per_unit = web_price / cantitate_roa if cantitate_roa != 1 else web_price
                elif sku in (direct_id_map or {}):
                    info = direct_id_map[sku]
                    id_articol = info["id_articol"] if isinstance(info, dict) else info
                    web_price_per_unit = web_price
                else:
                    continue

                pol = codmat_policy_map.get(sku, id_pol)
                result = compare_and_update_price(id_articol, pol, web_price_per_unit, conn)
                if result and result["updated"]:
                    updated.append(result)
    finally:
        if own_conn:
            database.pool.release(conn)

    return updated