from typing import Optional, Any, TYPE_CHECKING
if TYPE_CHECKING:
    from .inventory import Inventory  
    from .users import User

from sqlalchemy import Boolean, ForeignKeyConstraint, Identity, Integer, ForeignKey, Unicode, DateTime, text
from sqlalchemy.orm import Mapped, mapped_column, relationship
import datetime

from . import db

class WorkLog(db.Model):
    __tablename__ = 'Work Log'
    __table_args__ = (
        ForeignKeyConstraint(['Work Item'], ['Inventory.ID'], name='Work Log$InventoryWork Log'),
    )

    id: Mapped[int] = mapped_column("ID", Integer, Identity(start=1, increment=1), primary_key=True)
    start_time: Mapped[Optional[datetime.datetime]] = mapped_column('Start Timestamp', DateTime)
    end_time: Mapped[Optional[datetime.datetime]] = mapped_column('End Timestamp', DateTime)
    notes: Mapped[Optional[str]] = mapped_column('Description & Notes', Unicode())
    complete: Mapped[Optional[bool]] = mapped_column("Complete", Boolean, server_default=text('((0))'))
    followup: Mapped[Optional[bool]] = mapped_column('Needs Follow-Up', Boolean, server_default=text('((0))'))
    contact_id: Mapped[Optional[int]] = mapped_column('Point of Contact', Integer, ForeignKey("Users.ID"))
    analysis: Mapped[Optional[bool]] = mapped_column('Needs Quick Analysis', Boolean, server_default=text('((0))'))
    work_item_id: Mapped[Optional[int]] = mapped_column("Work Item", Integer, ForeignKey("Inventory.ID"))

    work_item: Mapped[Optional['Inventory']] = relationship('Inventory', back_populates='work_logs')
    contact: Mapped[Optional['User']] = relationship('User', back_populates='work_logs')

    def __init__(self, start_time: Optional[datetime.datetime] = None, end_time: Optional[datetime.datetime] = None,
                    notes: Optional[str] = None, complete: Optional[bool] = False,
                    followup: Optional[bool] = False, contact_id: Optional[int] = None,
                    analysis: Optional[bool] = False, work_item_id: Optional[int] = None):
            self.start_time = start_time
            self.end_time = end_time
            self.notes = notes
            self.complete = complete
            self.followup = followup
            self.contact_id = contact_id
            self.analysis = analysis
            self.work_item_id = work_item_id

    def __repr__(self):
        return f"<WorkLog(id={self.id}, start_time={self.start_time}, end_time={self.end_time}, " \
               f"notes={repr(self.notes)}, complete={self.complete}, followup={self.followup}, " \
               f"contact_id={self.contact_id}, analysis={self.analysis}, work_item_id={self.work_item_id})>"

    def serialize(self):
        return {
            'id': self.id,
            'start_time': self.start_time.isoformat() if self.start_time else None,
            'end_time': self.end_time.isoformat() if self.end_time else None,
            'notes': self.notes,
            'complete': self.complete,
            'followup': self.followup,
            'contact_id': self.contact_id,
            'analysis': self.analysis,
            'work_item_id': self.work_item_id
        }
    
    @classmethod
    def from_dict(cls, data: dict[str, Any]) -> "WorkLog":
        start_time_str = data.get("start_time")
        end_time_str = data.get("end_time")

        return cls(
            start_time=datetime.datetime.fromisoformat(str(start_time_str)) if start_time_str else datetime.datetime.now(),
            end_time=datetime.datetime.fromisoformat(str(end_time_str)) if end_time_str else None,
            notes=data.get("notes"),
            complete=bool(data.get("complete", False)),
            followup=bool(data.get("followup", False)),
            analysis=bool(data.get("analysis", False)),
            contact_id=data.get("contact_id"),
            work_item_id=data.get("work_item_id")
        )