"""Signature model for electronic signatures."""
import enum
from datetime import datetime
from typing import Optional

from sqlalchemy import String, Text, DateTime, Enum as SQLEnum, Integer, ForeignKey, JSON
from sqlalchemy.orm import Mapped, mapped_column

from app.core.database import Base


class SignatureStatus(str, enum.Enum):
    """Signature status enumeration."""
    PENDING = "pending"
    SIGNED = "signed"
    REJECTED = "rejected"
    EXPIRED = "expired"


class SignatureRequest(Base):
    """Signature request model."""

    __tablename__ = "signature_requests"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    contract_id: Mapped[int] = mapped_column(Integer, ForeignKey("contracts.id"), index=True)
    requester_id: Mapped[int] = mapped_column(Integer, ForeignKey("users.id"), index=True)
    signer_name: Mapped[str] = mapped_column(String(100))
    signer_email: Mapped[str] = mapped_column(String(100))
    status: Mapped[SignatureStatus] = mapped_column(
        SQLEnum(SignatureStatus),
        default=SignatureStatus.PENDING
    )
    token: Mapped[str] = mapped_column(String(64), unique=True, index=True)
    expires_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)

    def __init__(
        self,
        contract_id: int,
        requester_id: int,
        signer_name: str,
        signer_email: str,
        token: str,
        expires_at: datetime,
        status: SignatureStatus = SignatureStatus.PENDING,
        **kwargs
    ):
        self.contract_id = contract_id
        self.requester_id = requester_id
        self.signer_name = signer_name
        self.signer_email = signer_email
        self.token = token
        self.expires_at = expires_at
        self.status = status
        self.created_at = datetime.utcnow()


class Signature(Base):
    """Signature record model."""

    __tablename__ = "signatures"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    request_id: Mapped[int] = mapped_column(Integer, ForeignKey("signature_requests.id"), index=True)
    signer_name: Mapped[str] = mapped_column(String(100))
    signature_data: Mapped[str] = mapped_column(Text)  # Base64 image or coordinates
    ip_address: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)
    user_agent: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    verification_hash: Mapped[str] = mapped_column(String(64))  # Document fingerprint
    signed_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)

    def __init__(
        self,
        request_id: int,
        signer_name: str,
        signature_data: str,
        verification_hash: str,
        ip_address: Optional[str] = None,
        user_agent: Optional[str] = None,
        **kwargs
    ):
        self.request_id = request_id
        self.signer_name = signer_name
        self.signature_data = signature_data
        self.verification_hash = verification_hash
        self.ip_address = ip_address
        self.user_agent = user_agent
        self.signed_at = datetime.utcnow()


class SignatureAudit(Base):
    """Signature audit log model."""

    __tablename__ = "signature_audits"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    signature_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("signatures.id"), nullable=True)
    request_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("signature_requests.id"), nullable=True)
    action: Mapped[str] = mapped_column(String(50))
    details: Mapped[Optional[dict]] = mapped_column(JSON, nullable=True)
    ip_address: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)

    def __init__(
        self,
        action: str,
        signature_id: Optional[int] = None,
        request_id: Optional[int] = None,
        details: Optional[dict] = None,
        ip_address: Optional[str] = None,
        **kwargs
    ):
        self.action = action
        self.signature_id = signature_id
        self.request_id = request_id
        self.details = details
        self.ip_address = ip_address
        self.created_at = datetime.utcnow()