from __future__ import annotations
from datetime import datetime
from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, relationship
from sqlalchemy.sql import func
from sqlalchemy import String, ForeignKey, BigInteger, UniqueConstraint, Text, DateTime
from sqlalchemy.dialects.postgresql import ARRAY
import enum
from typing import List, Optional


class Base(DeclarativeBase):
    pass


class Sessions(Base):
    __tablename__ = "sessions"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(String(8), unique=True, nullable=False)
    patient_id: Mapped[int] = mapped_column(
        ForeignKey("patients.id", ondelete="CASCADE"), nullable=False)
    patient: Mapped["Patients"] = relationship(back_populates="sessions")
    sent_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    consulted_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    doctor_id: Mapped[int] = mapped_column(ForeignKey("doctors.id"))
    session_status_history: Mapped[List["SessionStatusHistory"]] = relationship(
        back_populates="sessions", cascade="all, delete-orphan")
    session_date_time_history: Mapped[List["SessionDateTimeHistory"]] = relationship(
        back_populates="sessions", cascade="all, delete-orphan")
    paid_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)


class SessionDateTimeHistory(Base):
    __tablename__ = "session_date_time_history"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    sessions_id: Mapped[int] = mapped_column(ForeignKey("sessions.id", ondelete="CASCADE"), nullable=False)
    sessions: Mapped["Sessions"] = relationship(back_populates="session_date_time_history")
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    consultation_date_time: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    who_updated: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)


class SessionStatusHistory(Base):
    __tablename__ = "session_status_history"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    sessions_id: Mapped[int] = mapped_column(ForeignKey("sessions.id", ondelete="CASCADE"), nullable=False)
    sessions: Mapped["Sessions"] = relationship(back_populates="session_status_history")
    updated_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    status: Mapped[str] = mapped_column(String(50), nullable=False, default="pending")
    who_updated: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)


class Admins(Base):
    __tablename__ = "admins"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    telegram_id: Mapped[int] = mapped_column(BigInteger, unique=True, nullable=False)
    created_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    available_payment_methods: Mapped[Optional[List[str]]] = mapped_column(
        ARRAY(String), nullable=True)


class Patients(Base):
    __tablename__ = "patients"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    telegram_id: Mapped[int] = mapped_column(BigInteger, unique=True, nullable=False)
    phone: Mapped[Optional[str]] = mapped_column(nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    updated_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    accepted_terms: Mapped[bool] = mapped_column(default=False, nullable=True)
    sessions: Mapped[List["Sessions"]] = relationship(
        back_populates="patient", cascade="all, delete-orphan")


class Doctors(Base):
    __tablename__ = "doctors"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(unique=True, nullable=True)
    time_zone: Mapped[Optional[str]] = mapped_column(nullable=True)
    telegram_id: Mapped[int] = mapped_column(BigInteger, unique=True, nullable=False)
    name: Mapped[str] = mapped_column(nullable=False)
    available_formats: Mapped[Optional[List[str]]
                              ] = mapped_column(ARRAY(String), nullable=True)
    is_active: Mapped[bool] = mapped_column(default=False, nullable=False)
    is_verified: Mapped[bool] = mapped_column(default=False, nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    referral_code_id: Mapped[int] = mapped_column(
        ForeignKey("referral_codes.id"), nullable=False)
    specialties: Mapped[List[str]] = mapped_column(
        ARRAY(String), nullable=False, default=list)
    referral: Mapped["ReferralCode"] = relationship(
        back_populates="doctor", uselist=False)
    sessions: Mapped[List["Sessions"]] = relationship()
    form_links: Mapped[List["FormLink"]] = relationship(
        back_populates="doctor", cascade="all, delete-orphan")
    payment_methods: Mapped[List["PaymentMethod"]] = relationship(
        back_populates="doctor", cascade="all, delete-orphan")
    verification_requests: Mapped[List["VerificationRequests"]] = relationship(
        back_populates="doctor", cascade="all, delete-orphan")

    def __repr__(self) -> str:
        return f"<Doctors(telegram_id={self.telegram_id!r}, name={self.name!r}, is_active={self.is_active})>"


class ReferralCode(Base):
    __tablename__ = "referral_codes"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(unique=True, nullable=False)
    is_used: Mapped[bool] = mapped_column(default=False, nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    used_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    doctor: Mapped[Optional["Doctors"]] = relationship(
        back_populates="referral", uselist=False)

    def __repr__(self) -> str:
        return f"<ReferralCode(code={self.code!r}, is_used={self.is_used})>"


class VerificationRequests(Base):
    __tablename__ = "verification_requests"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    doctor_id: Mapped[int] = mapped_column(
        ForeignKey("doctors.id", ondelete="CASCADE"), unique=True, nullable=False)
    code: Mapped[str] = mapped_column(unique=True, nullable=False)
    sent_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    reviewed_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    status: Mapped[str] = mapped_column(default=False, nullable=False)
    # Связь поправлена — связь с doctor через doctor_id
    doctor: Mapped["Doctors"] = relationship(
        back_populates="verification_requests")

    def __repr__(self) -> str:
        return f"<VerificationRequests(code={self.code!r}, status={self.status!r}, sent_at={self.sent_at!r})>"


class FormLink(Base):
    __tablename__ = "form_links"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    doctor_id: Mapped[int] = mapped_column(
        ForeignKey("doctors.id", ondelete="CASCADE"), unique=True, nullable=False)
    url: Mapped[str] = mapped_column(nullable=False)
    label: Mapped[Optional[str]] = mapped_column(nullable=True)
    is_active: Mapped[bool] = mapped_column(default=True, nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())

    doctor: Mapped["Doctors"] = relationship(back_populates="form_links")


class PaymentMethod(Base):
    __tablename__ = "payment_methods"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    doctor_id: Mapped[int] = mapped_column(
        ForeignKey("doctors.id", ondelete="CASCADE"), unique=True, nullable=False)
    method: Mapped[str] = mapped_column(nullable=False)
    details: Mapped[Optional[str]] = mapped_column(nullable=True)
    payment_api_key: Mapped[str] = mapped_column(nullable=False)
    is_active: Mapped[bool] = mapped_column(default=True, nullable=False)
    is_primary: Mapped[bool] = mapped_column(default=True, nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())

    doctor: Mapped["Doctors"] = relationship(back_populates="payment_methods")


class PaymentsRegistered(Base):
    __tablename__ = "payments_registered"
    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    code: Mapped[str] = mapped_column(String(8), unique=True, nullable=False)
    mapped: Mapped[bool] = mapped_column(nullable=True)


class NotificationType(enum.Enum):
    PAYMENT_RECEIVED = "payment_received"
    FIRST_REMINDER_SENT = "first_reminder_sent"

class SessionNotification(Base):
    __tablename__ = "session_notifications"
    __table_args__ = (
        UniqueConstraint("session_id", "type", name="uq_session_notification_once"),
    )

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    session_id: Mapped[int] = mapped_column(ForeignKey("sessions.id", ondelete="CASCADE"), nullable=False)
    patient_id: Mapped[int] = mapped_column(ForeignKey("patients.id", ondelete="CASCADE"), nullable=False)
    type: Mapped[NotificationType] = mapped_column(nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    sent_at: Mapped[Optional[datetime]] = mapped_column(DateTime(timezone=True), nullable=True)
    last_error: Mapped[Optional[str]] = mapped_column(Text, nullable=True)