from __future__ import annotations

from datetime import UTC, datetime
from typing import List, Optional

from sqlalchemy.orm import Mapped, mapped_column, relationship
from sqlmodel import Field, SQLModel


class ClassificationType:
    STANDARD = "standard_macrolactone"
    NON_STANDARD = "non_standard_macrocycle"
    NOT_MACROLACTONE = "not_macrolactone"


class ProcessingStatus:
    PENDING = "pending"
    SUCCESS = "success"
    FAILED = "failed"
    SKIPPED = "skipped"


# Define all tables without relationships first
class ParentMolecule(SQLModel, table=True):
    """Original molecule information."""

    __tablename__ = "parent_molecules"

    id: Optional[int] = Field(default=None, primary_key=True)
    ml_id: str = Field(index=True)  # MacrolactoneDB unique ID (e.g., ML00000001)
    chembl_id: Optional[str] = Field(default=None, index=True)  # Original CHEMBL ID
    molecule_name: Optional[str] = None
    smiles: str = Field(index=True)
    classification: str = Field(index=True)
    ring_size: Optional[int] = Field(default=None, index=True)
    primary_reason_code: Optional[str] = None
    primary_reason_message: Optional[str] = None
    processing_status: str = Field(default=ProcessingStatus.PENDING)
    error_message: Optional[str] = None
    num_sidechains: Optional[int] = None
    cleavage_positions: Optional[str] = None
    numbered_image_path: Optional[str] = None
    created_at: datetime = Field(default_factory=lambda: datetime.now(UTC))
    processed_at: Optional[datetime] = None


class RingNumbering(SQLModel, table=True):
    """Ring numbering details."""

    __tablename__ = "ring_numberings"

    id: Optional[int] = Field(default=None, primary_key=True)
    parent_id: int = Field(foreign_key="parent_molecules.id", unique=True)
    ring_size: int
    carbonyl_carbon_idx: int
    ester_oxygen_idx: int
    position_to_atom: str
    atom_to_position: str


class SideChainFragment(SQLModel, table=True):
    """Side chain fragments from cleavage."""

    __tablename__ = "side_chain_fragments"

    id: Optional[int] = Field(default=None, primary_key=True)
    parent_id: int = Field(foreign_key="parent_molecules.id", index=True)
    fragment_id: str = Field(index=True)
    cleavage_position: int = Field(index=True)
    attachment_atom_idx: int
    attachment_atom_symbol: str
    fragment_smiles_labeled: str
    fragment_smiles_plain: str
    dummy_isotope: int
    has_dummy_atom: bool = Field(default=True)
    dummy_atom_count: int = Field(default=1)
    atom_count: int
    heavy_atom_count: int
    molecular_weight: float
    original_bond_type: str
    image_path: Optional[str] = None


class FragmentLibraryEntry(SQLModel, table=True):
    """Unified fragment library entries."""

    __tablename__ = "fragment_library_entries"

    id: Optional[int] = Field(default=None, primary_key=True)
    source_type: str = Field(index=True)
    source_fragment_id: Optional[str] = Field(default=None, index=True)
    source_parent_ml_id: Optional[str] = Field(default=None, index=True)
    source_parent_chembl_id: Optional[str] = Field(default=None, index=True)
    cleavage_position: Optional[int] = Field(default=None, index=True)
    fragment_smiles_labeled: Optional[str] = None
    fragment_smiles_plain: str
    has_dummy_atom: bool = Field(default=False)
    dummy_atom_count: int = Field(default=0)
    splice_ready: bool = Field(default=False, index=True)
    original_bond_type: Optional[str] = None
    created_at: datetime = Field(default_factory=lambda: datetime.now(UTC))


class ValidationResult(SQLModel, table=True):
    """Manual validation records."""

    __tablename__ = "validation_results"

    id: Optional[int] = Field(default=None, primary_key=True)
    parent_id: int = Field(foreign_key="parent_molecules.id")
    numbering_correct: Optional[bool] = None
    cleavage_correct: Optional[bool] = None
    classification_correct: Optional[bool] = None
    notes: Optional[str] = None
    validated_by: Optional[str] = None
    validated_at: Optional[datetime] = None