from sqlalchemy import (
    Column, String, Integer, Date, DateTime, Text, ForeignKey, Index, UniqueConstraint
)
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func

from app.database import Base


class Bill(Base):
    __tablename__ = "bills"

    # Natural key: "{congress}-{bill_type_lower}-{bill_number}" e.g. "119-hr-1234"
    bill_id = Column(String, primary_key=True)
    congress_number = Column(Integer, nullable=False)
    bill_type = Column(String(10), nullable=False)  # hr, s, hjres, sjres, hconres, sconres, hres, sres
    bill_number = Column(Integer, nullable=False)
    title = Column(Text)
    short_title = Column(Text)
    sponsor_id = Column(String, ForeignKey("members.bioguide_id"), nullable=True)
    introduced_date = Column(Date)
    latest_action_date = Column(Date)
    latest_action_text = Column(Text)
    status = Column(String(100))
    chamber = Column(String(50))
    congress_url = Column(String)
    govtrack_url = Column(String)

    bill_category = Column(String(20), nullable=True)  # substantive | commemorative | administrative
    cosponsors_fetched_at = Column(DateTime(timezone=True))

    # Ingestion tracking
    last_checked_at = Column(DateTime(timezone=True))
    actions_fetched_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())

    sponsor = relationship("Member", back_populates="bills", foreign_keys=[sponsor_id])
    actions = relationship("BillAction", back_populates="bill", order_by="desc(BillAction.action_date)")
    documents = relationship("BillDocument", back_populates="bill")
    briefs = relationship("BillBrief", back_populates="bill", order_by="desc(BillBrief.created_at)")
    news_articles = relationship("NewsArticle", back_populates="bill", order_by="desc(NewsArticle.published_at)")
    trend_scores = relationship("TrendScore", back_populates="bill", order_by="desc(TrendScore.score_date)")
    committee_bills = relationship("CommitteeBill", back_populates="bill")
    notes = relationship("BillNote", back_populates="bill", cascade="all, delete-orphan")
    cosponsors = relationship("BillCosponsor", back_populates="bill", cascade="all, delete-orphan")

    __table_args__ = (
        Index("ix_bills_congress_number", "congress_number"),
        Index("ix_bills_latest_action_date", "latest_action_date"),
        Index("ix_bills_introduced_date", "introduced_date"),
        Index("ix_bills_chamber", "chamber"),
        Index("ix_bills_sponsor_id", "sponsor_id"),
    )


class BillAction(Base):
    __tablename__ = "bill_actions"

    id = Column(Integer, primary_key=True, autoincrement=True)
    bill_id = Column(String, ForeignKey("bills.bill_id", ondelete="CASCADE"), nullable=False)
    action_date = Column(Date)
    action_text = Column(Text)
    action_type = Column(String(100))
    chamber = Column(String(50))
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    bill = relationship("Bill", back_populates="actions")

    __table_args__ = (
        Index("ix_bill_actions_bill_id", "bill_id"),
        Index("ix_bill_actions_action_date", "action_date"),
    )


class BillDocument(Base):
    __tablename__ = "bill_documents"

    id = Column(Integer, primary_key=True, autoincrement=True)
    bill_id = Column(String, ForeignKey("bills.bill_id", ondelete="CASCADE"), nullable=False)
    doc_type = Column(String(50))   # bill_text | committee_report | amendment
    doc_version = Column(String(50))  # Introduced, Enrolled, etc.
    govinfo_url = Column(String)
    raw_text = Column(Text)
    fetched_at = Column(DateTime(timezone=True))
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    bill = relationship("Bill", back_populates="documents")
    briefs = relationship("BillBrief", back_populates="document")

    __table_args__ = (
        Index("ix_bill_documents_bill_id", "bill_id"),
    )


class BillCosponsor(Base):
    __tablename__ = "bill_cosponsors"

    id = Column(Integer, primary_key=True, autoincrement=True)
    bill_id = Column(String, ForeignKey("bills.bill_id", ondelete="CASCADE"), nullable=False)
    bioguide_id = Column(String, ForeignKey("members.bioguide_id", ondelete="SET NULL"), nullable=True)
    name = Column(String(200))
    party = Column(String(50))
    state = Column(String(10))
    sponsored_date = Column(Date, nullable=True)
    created_at = Column(DateTime(timezone=True), server_default=func.now())

    bill = relationship("Bill", back_populates="cosponsors")

    __table_args__ = (
        Index("ix_bill_cosponsors_bill_id", "bill_id"),
        Index("ix_bill_cosponsors_bioguide_id", "bioguide_id"),
    )