import json
import os
import shutil
from pathlib import Path
from datetime import datetime
from dotenv import load_dotenv
from lxml import etree
from jinja2 import Environment, FileSystemLoader
from logger_manager import get_logger

# ============================================================================
_BASE = Path(__file__).resolve().parent
# load_dotenv(_BASE / ".env")
# load_dotenv(_BASE.parent / ".env")

load_dotenv(dotenv_path=".env")

INPUT_DIR = Path(os.getenv("INPUT_DIR", "data/input"))
PROCESSED_DIR = Path("data/processed")
OUTPUT_DIR = Path("data/output")
HTML_DIR = Path("data/html")
SAP_B1_DIR = Path("data/sap_b1")
ERRORS_DIR = Path("data/errors")
TEMPLATE_FILE = _BASE / "template.html"

POST_TO_SAP_B1 = True

TEXT_MONTHS = {
    1: "enero", 2: "febrero", 3: "marzo", 4: "abril",
    5: "mayo", 6: "junio", 7: "julio", 8: "agosto",
    9: "septiembre", 10: "octubre", 11: "noviembre", 12: "diciembre",
}
# ============================================================================
log = get_logger()

# ============================================================================
def _format_date(d: str) -> str:
    if not d:
        return ""
    p = d.split("-")
    if len(p) == 3:
        return f"{p[2][:2]} de {TEXT_MONTHS.get(int(p[1]), p[1])} de {p[0]}"
    return d

# ============================================================================
def _format_datetime(dt: str) -> str:
    if not dt:
        return ""
    dp = dt.split("T")[0]
    tp = dt.split("T")[1][:5] if "T" in dt else ""
    fd = _format_date(dp)
    return f"{fd} {tp} hrs." if tp else fd

# ============================================================================
def _event_text(ev: str) -> str:
    return {"DATE_OF_INVOICE": "fecha de factura", "RECEIPT_OF_GOODS": "recepción de mercadería"}.get(ev, ev or "")

# ============================================================================
def apply_allowances(net_price: int, qty: int, allowances: list) -> tuple:
    total = net_price * qty
    applied = []
    for alw in allowances:
        pct = alw.get("percentage", 0)
        if pct > 0:
            dsc = round(total * pct / 100)
        else:
            dsc = round(alw.get("amount", 0))
        applied.append({"type": alw.get("type"), "percentage": pct, "amount": dsc})
        total -= dsc
    return total, applied

# ============================================================================
def _strip_ns(root):
    for el in root.iter():
        if "}" in el.tag:
            el.tag = el.tag.split("}", 1)[1]
    etree.cleanup_namespaces(root)
    return root

# ============================================================================
def _x(node, path, default=None):
    v = node.xpath(path)
    return v[0] if v else default

# ============================================================================
def _t(node, path, default=""):
    v = _x(node, path)
    return v.text.strip() if v is not None and v.text else default

# ============================================================================
def _a(node, path, attr, default=""):
    v = _x(node, path)
    return v.get(attr, default) if v is not None else default

# ============================================================================
def _l(node, path):
    return node.xpath(path)

# ============================================================================
def substring_desde_fin(texto: str, cantidad: int = 10, excluir_ultimos: int = 1) -> str:
    inicio = -(cantidad + excluir_ultimos)
    fin = -excluir_ultimos if excluir_ultimos > 0 else None
    return texto[inicio:fin]

# ============================================================================
def parse_order(xml_bytes: bytes, filename: str = "") -> dict:
    root = _strip_ns(etree.fromstring(xml_bytes))
    order = _x(root, "//order")
    if order is None:
        raise ValueError("Elemento <order> no encontrado")

    msg = _x(root, "//messageHeader")
    oc_id = _x(
        order,
        'typedEntityIdentification[@entityType="ORDER"]/entityIdentification/uniqueCreatorIdentification',
    )
    oc_num = oc_id.text.strip() if oc_id is not None and oc_id.text else ""

    cd = order.get("creationDate", "")
    pt = _x(order, "paymentTerms")
    event = pt.get("eventType", "") if pt is not None else ""
    net_days = _t(order, "paymentTerms/netPayment/timePeriodDue")

    cab = {
        "emisor": _t(msg, "from/gln") if msg is not None else "",
        "receptor": _t(msg, "to/gln") if msg is not None else "",
        "numero_oc": substring_desde_fin(oc_num) if (oc_num is not None and len(oc_num) > 10) else "",
        "fecha_generacion": cd,
        "fecha_generacion_format": _format_datetime(cd),
        "fecha_embarque": _t(order, "movementDate"),
        "fecha_embarque_format": _format_date(_t(order, "movementDate")),
        "fecha_cancelacion": "",
        "fecha_cancelacion_format": "",
        "condiciones_pago": f"NET {net_days} días desde {_event_text(event)}" if net_days else "",
        "condiciones_pago_texto": f"NET {net_days} días desde {_event_text(event)}" if net_days else "",
        "lugar_entrega": _t(order, 'shipParty[@identificationType="SHIP_TO"]/gln'),
        "dpto_ventas": _t(order, "salesDepartamentNumber"),
        "tipo_oc": _t(order, "orderType"),
        "promocion": _t(order, "promotionDealNumber"),
        "numero_proveedor": _t(order, "internalVendorNumber"),
        "observaciones": _t(order, "specialHandling"),
    }

    carrier = _x(root, "//mainCarrierTransport")
    if carrier is not None:
        cab["etapa_transporte"] = _t(carrier, "mode")
        cab["transportista"] = _t(carrier, "carrierName")
        cab["divisa"] = _t(carrier, "../../currency") or _t(carrier, "../../../currency") or _t(carrier, "../currency")

    detalle = []
    for item in _l(order, "lineItem"):
        np = int(_t(item, "netPrice/amount", "0"))
        rq = int(_t(item, "requestedQuantity", "0"))
        cu = int(_t(item, "containedUnits", "0"))
        ta = int(_t(item, "totalAmount/amount", "0"))
        currency = _a(item, "netPrice/amount", "currencyISOcode", "CLP")

        alw_list = []
        for alw in _l(item, "allowanceCharge"):
            alw_list.append({
                "type": alw.get("allowanceOrChargeType", ""),
                "percentage": int(_t(alw, "monetaryAmountOrPercentage/percentage", "0")),
                "amount": int(_t(alw, "monetaryAmountOrPercentage/amount", "0")),
            })

        calc_total, applied_alw = apply_allowances(np, rq, alw_list)
        color = _t(item, "itemColor")
        size = _t(item, "itemSize")

        detalle.append({
            "linea": item.get("number", ""),
            "cod_upc": _t(item, "itemIdentification/gtin"),
            "item": _t(item, "itemIdentification/buyerItemNumber"),
            "cod_prov": _t(item, "itemIdentification/vendorItemNumber"),
            "color_talla_um": "/ ".join(filter(None, [color, size])),
            "descripcion": _t(item, 'itemDescription[@language="SP"]/text'),
            "precio_original": np,
            "moneda": currency,
            "allowances": applied_alw,
            "precio_efectivo": round(calc_total / rq) if rq > 0 else 0,
            "empaques": rq,
            "unidad_empaque": _a(item, "requestedQuantity", "UnitType", ""),
            "unid_empaque": cu,
            "cantidad_unid": rq * cu,
            "importe": ta,
        })

    return {
        "metadata": {"archivo": filename, "procesado": datetime.now().isoformat()},
        "cabecera": cab,
        "detalle": detalle,
        "totales": {
            "importe_total": sum(d["importe"] for d in detalle),
            "moneda": detalle[0]["moneda"] if detalle else "CLP",
        },
    }

# ============================================================================
def write_json(data: dict, path: Path):
    path.parent.mkdir(parents=True, exist_ok=True)
    with open(path, "w", encoding="utf-8") as f:
        json.dump(data, f, ensure_ascii=False, indent=2)

# ============================================================================
def write_html(data: dict, template_path: Path, output_path: Path):
    env = Environment(loader=FileSystemLoader(str(template_path.parent)))
    template = env.get_template(template_path.name)
    output_path.parent.mkdir(parents=True, exist_ok=True)
    with open(output_path, "w", encoding="utf-8") as f:
        f.write(template.render(data=data))

# ============================================================================
def process_file(xml_path: Path):
    with log.task(f"📦 {xml_path.name}"):
        log.info("📄 XML parseado")
        with open(xml_path, "rb") as f:
            data = parse_order(f.read(), filename=xml_path.name)

        base = xml_path.stem
        write_json(data, OUTPUT_DIR / f"{base}.json")
        log.info("💾 JSON guardado")

        write_html(data, TEMPLATE_FILE, HTML_DIR / f"{base}.html")
        log.info("💾 HTML generado")

        if POST_TO_SAP_B1:
            with log.task("🔐 SAP B1"):
                try:
                    from sapb1_mapper import to_draft_payload
                    from sapb1_manager import create_orders
                    from sql_manager import get_client_by_gln, get_item_catalog, get_price_list, get_prices, get_card_name
                    from email_reporter import generate_email_html

                    cab = data.get("cabecera", {})
                    emisor = cab.get("emisor", "")
                    lugar_entrega = cab.get("lugar_entrega", "")

                    result = get_client_by_gln(emisor, lugar_entrega)

                    if result:
                        cardcode = result["CardCode"]
                        city = result["City"]
                        county = result["County"]
                        log.info("CardCode={} (desde CRD1)".format(cardcode))
                    else:
                        cardcode = ""
                        log.warning("No se obtuvo Socio de negocios para el {}.{}".format(emisor, lugar_entrega))
                        try:
                            from mail_sender import send_mail
                            send_mail(
                                subject=f"OC {cab.get('numero_oc', '')} — Sin socio de negocios",
                                text=f"No se obtuvo Socio de negocios para el {emisor}.{lugar_entrega}",
                            )
                            log.info("Correo de notificación enviado")
                        except Exception as e:
                            log.warning("Error enviando correo de notificación: {}".format(e))
                        ERRORS_DIR.mkdir(parents=True, exist_ok=True)
                        shutil.move(str(xml_path), str(ERRORS_DIR / xml_path.name))
                        log.info("📁 XML movido a errors/")
                        return

                    item_catalog = get_item_catalog(cardcode)
                    pricelist = get_price_list(cardcode)
                    prices = get_prices(pricelist) if pricelist else {}
                    log.info("Catálogo: {} items, precios: {} registros".format(len(item_catalog), len(prices)))

                    cardname = get_card_name(cardcode)
                    email_html = generate_email_html(data, cardcode, cardname, item_catalog, prices)
                    (HTML_DIR / f"{base}_email.html").write_text(email_html, encoding="utf-8")
                    log.info("Email HTML generado")

                    payload = to_draft_payload(data, cardcode=cardcode, city=city, county=county, item_catalog=item_catalog, prices=prices)
                    write_json(payload, SAP_B1_DIR / f"{base}_sap.json")
                    log.info("Payload guardado en data/sap_b1/")

                    det = data.get("detalle", [])
                    price_ok = True
                    for d in det:
                        upc = d.get("cod_upc", "") or ""
                        sap_item = item_catalog.get(upc, "")
                        sap_price = prices.get(sap_item) if sap_item else None
                        importe = d.get("importe", 0) or 0
                        qty = d.get("cantidad_unid", 1) or 1
                        precio_xml = round(importe / qty) if qty > 0 else 0
                        if not sap_item or sap_price is None or sap_price != precio_xml:
                            price_ok = False
                            log.warning("⚠️ {}: difiere (XML={} vs SAP={})".format(upc, precio_xml, sap_price))

                    if not price_ok:
                        email_path = HTML_DIR / f"{base}_email.html"
                        num_oc = cab.get("numero_oc", "") or base
                        try:
                            from mail_sender import send_validation_email
                            send_validation_email(
                                email_path,
                                subject=f"Validación OC {num_oc} — diferencias precio/catálogo",
                            )
                            log.info("Notificación enviada a MAIL_TO")
                        except Exception as e:
                            log.warning("Error enviando correo: {}".format(e))

                    create_orders(payload)
                except ImportError as e:
                    log.warning("⚠️ SAP saltado (dependencia faltante: {})".format(e))
                except Exception as e:
                    log.warning("❌ SAP error: {}".format(e))

        PROCESSED_DIR.mkdir(parents=True, exist_ok=True)
        shutil.move(str(xml_path), str(PROCESSED_DIR / xml_path.name))
        log.info("📁 XML movido a processed/")

# ============================================================================
def process_all():
    INPUT_DIR.mkdir(parents=True, exist_ok=True)
    files = sorted(f for f in INPUT_DIR.iterdir() if f.is_file())
    if not files:
        return
    log.info("📦 Archivos pendientes: {}".format(len(files)))
    for f in files:
        try:
            process_file(f)
        except Exception as e:
            log.error("❌ Error con {}: {}".format(f.name, e))

# ============================================================================