feat: work shifts planning

models/work_shifts.py

@@ -1,14 +1,14 @@
-from datetime import datetime
+from datetime import datetime, date
 from typing import TYPE_CHECKING
 
-from sqlalchemy import ForeignKey
+from sqlalchemy import ForeignKey, Table, Column
 from sqlalchemy.sql import expression
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
 from models.base import BaseModel
 
 if TYPE_CHECKING:
-    from models import User
+    from models import User, Position
 
 
 class WorkShift(BaseModel):
@@ -63,3 +63,29 @@ class WorkShiftPause(BaseModel):
         back_populates="pauses",
         lazy="selectin",
     )
+
+
+work_shifts_positions = Table(
+    'work_shifts_positions',
+    BaseModel.metadata,
+    Column('position_key', ForeignKey('positions.key'), primary_key=True),
+    Column('work_shift_id', ForeignKey('planned_work_shifts.id'), primary_key=True),
+)
+
+
+class PlannedWorkShift(BaseModel):
+    __tablename__ = "planned_work_shifts"
+
+    id: Mapped[int] = mapped_column(primary_key=True)
+    shift_date: Mapped[date] = mapped_column(nullable=False, index=True)
+    created_at: Mapped[datetime] = mapped_column(nullable=False)
+
+    user_id: Mapped[int] = mapped_column(ForeignKey('users.id'), nullable=False, index=True)
+    user: Mapped["User"] = relationship(lazy="selectin", backref="planned_work_shifts")
+
+    positions: Mapped[list["Position"]] = relationship(
+        "Position",
+        uselist=True,
+        secondary=work_shifts_positions,
+        lazy="selectin",
+    )