import uuid
from datetime import datetime, date

from sqlalchemy import Date, DateTime, ForeignKey, String, Text, UniqueConstraint, func
from sqlalchemy.dialects.postgresql import UUID
from sqlalchemy.orm import Mapped, mapped_column

from app.db.base_class import Base


class Subject(Base):
    __tablename__ = "subjects"
    __table_args__ = (UniqueConstraint("study_id", "subject_no", name="uq_subject_study_no"),)

    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    study_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("studies.id"), index=True, nullable=False)
    site_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), ForeignKey("sites.id"), index=True, nullable=False)
    subject_no: Mapped[str] = mapped_column(String(50), nullable=False)
    status: Mapped[str] = mapped_column(String(20), nullable=False, default="SCREENING")
    screening_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    consent_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    enrollment_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    baseline_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    completion_date: Mapped[date | None] = mapped_column(Date, nullable=True)
    drop_reason: Mapped[str | None] = mapped_column(Text, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now())
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now()
    )