"""Contract model."""
import enum
from datetime import date, datetime
from typing import Optional

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

from app.core.database import Base


class ContractStatus(str, enum.Enum):
    """Contract status enumeration."""
    DRAFT = "draft"
    PENDING_APPROVAL = "pending_approval"
    APPROVED = "approved"
    PENDING_SIGNATURE = "pending_signature"
    SIGNED = "signed"
    ARCHIVED = "archived"
    REJECTED = "rejected"


class Contract(Base):
    """Contract model."""

    __tablename__ = "contracts"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    template_id: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("contract_templates.id"), nullable=True)
    title: Mapped[str] = mapped_column(String(200), index=True)
    contract_number: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)
    party_a: Mapped[str] = mapped_column(String(100))
    party_b: Mapped[str] = mapped_column(String(100))
    content: Mapped[str] = mapped_column(Text)
    status: Mapped[ContractStatus] = mapped_column(
        SQLEnum(ContractStatus),
        default=ContractStatus.DRAFT
    )
    effective_date: Mapped[Optional[date]] = mapped_column(Date, nullable=True)
    expiry_date: Mapped[Optional[date]] = mapped_column(Date, nullable=True)
    file_path: Mapped[Optional[str]] = mapped_column(String(255), nullable=True)
    created_by: Mapped[int] = mapped_column(Integer, ForeignKey("users.id"))
    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
    updated_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)

    def __init__(
        self,
        title: str,
        party_a: str,
        party_b: str,
        content: str,
        created_by: int,
        template_id: Optional[int] = None,
        contract_number: Optional[str] = None,
        status: ContractStatus = ContractStatus.DRAFT,
        effective_date: Optional[date] = None,
        expiry_date: Optional[date] = None,
        file_path: Optional[str] = None,
        **kwargs
    ):
        self.title = title
        self.party_a = party_a
        self.party_b = party_b
        self.content = content
        self.created_by = created_by
        self.template_id = template_id
        self.contract_number = contract_number
        self.status = status
        self.effective_date = effective_date
        self.expiry_date = expiry_date
        self.file_path = file_path
        self.created_at = datetime.utcnow()
        self.updated_at = datetime.utcnow()


class ContractTemplate(Base):
    """Contract template model."""

    __tablename__ = "contract_templates"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    name: Mapped[str] = mapped_column(String(100))
    contract_type: Mapped[Optional[str]] = mapped_column(String(50), nullable=True)
    content: Mapped[str] = mapped_column(Text)
    variables: Mapped[Optional[dict]] = mapped_column(String, nullable=True)  # JSON string
    created_by: Mapped[int] = mapped_column(Integer, ForeignKey("users.id"))
    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)

    def __init__(
        self,
        name: str,
        content: str,
        created_by: int,
        contract_type: Optional[str] = None,
        variables: Optional[dict] = None,
        **kwargs
    ):
        self.name = name
        self.content = content
        self.created_by = created_by
        self.contract_type = contract_type
        self.variables = variables
        self.created_at = datetime.utcnow()


class ContractApproval(Base):
    """Contract approval model."""

    __tablename__ = "contract_approvals"

    id: Mapped[int] = mapped_column(primary_key=True, autoincrement=True)
    contract_id: Mapped[int] = mapped_column(Integer, ForeignKey("contracts.id"), index=True)
    approver_id: Mapped[int] = mapped_column(Integer, ForeignKey("users.id"), index=True)
    status: Mapped[ContractStatus] = mapped_column(SQLEnum(ContractStatus))
    comment: Mapped[Optional[str]] = mapped_column(Text, nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, nullable=False)
    approved_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)

    def __init__(
        self,
        contract_id: int,
        approver_id: int,
        status: ContractStatus,
        comment: Optional[str] = None,
        **kwargs
    ):
        self.contract_id = contract_id
        self.approver_id = approver_id
        self.status = status
        self.comment = comment
        self.created_at = datetime.utcnow()