from datetime import datetime
from sqlalchemy import JSON, DateTime, Float, ForeignKey, Integer, String, Text, func
from sqlalchemy.orm import Mapped, mapped_column, relationship
from app.core.db import Base


class User(Base):
    __tablename__ = "users"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    email: Mapped[str] = mapped_column(String(255), unique=True, index=True, nullable=False)
    password_hash: Mapped[str] = mapped_column(String(255), nullable=False)
    role: Mapped[str] = mapped_column(String(20), nullable=False, default="viewer")
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now(), nullable=False)

    audit_logs: Mapped[list["AuditLog"]] = relationship(back_populates="user")


class Target(Base):
    __tablename__ = "targets"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    name: Mapped[str] = mapped_column(String(120), unique=True, index=True, nullable=False)
    host: Mapped[str] = mapped_column(String(255), nullable=False)
    port: Mapped[int] = mapped_column(Integer, nullable=False, default=5432)
    dbname: Mapped[str] = mapped_column(String(120), nullable=False)
    username: Mapped[str] = mapped_column(String(120), nullable=False)
    encrypted_password: Mapped[str] = mapped_column(Text, nullable=False)
    sslmode: Mapped[str] = mapped_column(String(20), nullable=False, default="prefer")
    tags: Mapped[dict] = mapped_column(JSON, nullable=False, default=dict)
    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now(), nullable=False)

    metrics: Mapped[list["Metric"]] = relationship(back_populates="target", cascade="all, delete-orphan")
    query_stats: Mapped[list["QueryStat"]] = relationship(back_populates="target", cascade="all, delete-orphan")


class Metric(Base):
    __tablename__ = "metrics"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    target_id: Mapped[int] = mapped_column(ForeignKey("targets.id", ondelete="CASCADE"), nullable=False, index=True)
    ts: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now(), index=True)
    metric_name: Mapped[str] = mapped_column(String(120), nullable=False, index=True)
    value: Mapped[float] = mapped_column(Float, nullable=False)
    labels: Mapped[dict] = mapped_column(JSON, nullable=False, default=dict)

    target: Mapped[Target] = relationship(back_populates="metrics")


class QueryStat(Base):
    __tablename__ = "query_stats"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    target_id: Mapped[int] = mapped_column(ForeignKey("targets.id", ondelete="CASCADE"), nullable=False, index=True)
    ts: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now(), index=True)
    queryid: Mapped[str] = mapped_column(String(100), nullable=False)
    calls: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    total_time: Mapped[float] = mapped_column(Float, nullable=False, default=0.0)
    mean_time: Mapped[float] = mapped_column(Float, nullable=False, default=0.0)
    rows: Mapped[int] = mapped_column(Integer, nullable=False, default=0)
    query_text: Mapped[str | None] = mapped_column(Text, nullable=True)

    target: Mapped[Target] = relationship(back_populates="query_stats")


class AuditLog(Base):
    __tablename__ = "audit_logs"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    ts: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False, server_default=func.now(), index=True)
    user_id: Mapped[int | None] = mapped_column(ForeignKey("users.id"), nullable=True, index=True)
    action: Mapped[str] = mapped_column(String(120), nullable=False)
    payload: Mapped[dict] = mapped_column(JSON, nullable=False, default=dict)

    user: Mapped[User | None] = relationship(back_populates="audit_logs")