"""DB 모델 정의"""

from datetime import datetime
from enum import Enum as PyEnum

from sqlalchemy import (
    Column, Integer, BigInteger, String, Float, DateTime,
    Enum, ForeignKey, Text, Boolean, Index,
)
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func

from app.database import Base


# ── 상태 Enum ──

class ChargerStatus(str, PyEnum):
    AVAILABLE = "Available"
    CHARGING = "Charging"
    FAULTED = "Faulted"
    UNAVAILABLE = "Unavailable"
    RESERVED = "Reserved"


class SessionStatus(str, PyEnum):
    PENDING = "pending"          # 결제 대기
    AUTHORIZED = "authorized"    # 결제 승인, 충전 시작 대기
    CHARGING = "charging"        # 충전 중
    COMPLETED = "completed"      # 정상 종료
    FAILED = "failed"            # 실패
    CANCELLED = "cancelled"      # 취소


class PaymentStatus(str, PyEnum):
    PENDING = "pending"
    CONFIRMED = "confirmed"
    FAILED = "failed"
    REFUNDED = "refunded"
    PARTIAL_REFUND = "partial_refund"


# ── 충전기 ──

class Charger(Base):
    __tablename__ = "chargers"

    id = Column(Integer, primary_key=True, autoincrement=True)
    charge_box_id = Column(String(64), unique=True, nullable=False, index=True,
                           comment="OCPP chargeBoxId (Steve 등록명)")
    name = Column(String(128), comment="표시 이름 (예: A동 주차장 1번)")
    location = Column(String(256), comment="설치 위치")
    connector_count = Column(Integer, default=1)
    power_kw = Column(Float, default=7.0, comment="충전 용량 kW")
    status = Column(Enum(ChargerStatus), default=ChargerStatus.UNAVAILABLE)
    last_heartbeat = Column(DateTime(timezone=True))
    is_active = Column(Boolean, default=True)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    sessions = relationship("ChargingSession", back_populates="charger")

    def __repr__(self):
        return f"<Charger {self.charge_box_id} [{self.status}]>"


# ── 충전 세션 ──

class ChargingSession(Base):
    __tablename__ = "charging_sessions"
    __table_args__ = (
        Index("ix_session_charger_status", "charger_id", "status"),
        Index("ix_session_created", "created_at"),
    )

    id = Column(Integer, primary_key=True, autoincrement=True)
    session_uid = Column(String(64), unique=True, nullable=False, index=True,
                         comment="고유 세션 ID (UUID)")
    charger_id = Column(Integer, ForeignKey("chargers.id"), nullable=False)
    connector_id = Column(Integer, default=1)

    # OCPP 트랜잭션 정보
    ocpp_transaction_id = Column(Integer, comment="Steve에서 발급한 transactionId")
    id_tag = Column(String(64), comment="OCPP 인증 태그")

    # 전력량 (Wh 단위)
    meter_start = Column(BigInteger, comment="시작 전력량 Wh")
    meter_stop = Column(BigInteger, comment="종료 전력량 Wh")
    charged_wh = Column(BigInteger, default=0, comment="충전된 전력량 Wh")
    last_meter_value = Column(BigInteger, comment="마지막 MeterValues Wh")

    # 요금
    electricity_cost = Column(Integer, default=0, comment="전기 원가 (원)")
    service_fee = Column(Integer, default=0, comment="서비스 수수료 (원)")
    total_bill = Column(Integer, default=0, comment="총 요금 (원)")

    # 시간
    status = Column(Enum(SessionStatus), default=SessionStatus.PENDING)
    started_at = Column(DateTime(timezone=True))
    stopped_at = Column(DateTime(timezone=True))
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    charger = relationship("Charger", back_populates="sessions")
    payment = relationship("Payment", back_populates="session", uselist=False)

    def __repr__(self):
        return f"<Session {self.session_uid} [{self.status}]>"


# ── 결제 ──

class Payment(Base):
    __tablename__ = "payments"
    __table_args__ = (
        Index("ix_payment_order", "order_id"),
    )

    id = Column(Integer, primary_key=True, autoincrement=True)
    session_id = Column(Integer, ForeignKey("charging_sessions.id"), nullable=False)

    # 토스페이먼츠
    order_id = Column(String(128), unique=True, nullable=False,
                      comment="토스 주문 ID")
    payment_key = Column(String(256), comment="토스 paymentKey")
    amount = Column(Integer, nullable=False, comment="결제 요청 금액 (원)")
    actual_amount = Column(Integer, comment="실제 충전 후 정산 금액")

    status = Column(Enum(PaymentStatus), default=PaymentStatus.PENDING)
    method = Column(String(32), comment="결제 수단 (카드, 간편결제 등)")
    card_company = Column(String(32), comment="카드사 이름")

    confirmed_at = Column(DateTime(timezone=True))
    refunded_at = Column(DateTime(timezone=True))
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    session = relationship("ChargingSession", back_populates="payment")

    def __repr__(self):
        return f"<Payment {self.order_id} [{self.status}]>"


# ── 충전기 MeterValue 로그 ──

class MeterValueLog(Base):
    """실시간 MeterValues 로그 (디버깅/분석용)"""
    __tablename__ = "meter_value_logs"

    id = Column(BigInteger, primary_key=True, autoincrement=True)
    charger_id = Column(Integer, ForeignKey("chargers.id"), nullable=False)
    transaction_id = Column(Integer)
    connector_id = Column(Integer, default=1)
    measurand = Column(String(64), default="Energy.Active.Import.Register")
    value = Column(Float, nullable=False, comment="측정값")
    unit = Column(String(16), default="Wh")
    timestamp = Column(DateTime(timezone=True), server_default=func.now())


# ── 사용자 ──

class UserRole(str, PyEnum):
    ADMIN = "admin"
    OPERATOR = "operator"
    VIEWER = "viewer"


class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True, autoincrement=True)
    username = Column(String(64), unique=True, nullable=False, index=True)
    hashed_password = Column(String(256), nullable=False)
    display_name = Column(String(128), comment="표시 이름")
    role = Column(Enum(UserRole), default=UserRole.VIEWER)
    is_active = Column(Boolean, default=True)
    last_login = Column(DateTime(timezone=True))
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    def __repr__(self):
        return f"<User {self.username} [{self.role}]>"