feat: add initial database models and changelog for financial inputs and projects

models/simulation_parameter.py

@@ -0,0 +1,69 @@
+from __future__ import annotations
+
+from datetime import datetime
+from enum import Enum
+from typing import TYPE_CHECKING
+
+from sqlalchemy import (
+    JSON,
+    DateTime,
+    Enum as SQLEnum,
+    ForeignKey,
+    Integer,
+    Numeric,
+    String,
+)
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+from sqlalchemy.sql import func
+
+from config.database import Base
+
+if TYPE_CHECKING:  # pragma: no cover
+    from .scenario import Scenario
+
+
+class DistributionType(str, Enum):
+    """Supported stochastic distribution families for simulations."""
+
+    NORMAL = "normal"
+    TRIANGULAR = "triangular"
+    UNIFORM = "uniform"
+    LOGNORMAL = "lognormal"
+    CUSTOM = "custom"
+
+
+class SimulationParameter(Base):
+    """Probability distribution settings for scenario simulations."""
+
+    __tablename__ = "simulation_parameters"
+
+    id: Mapped[int] = mapped_column(Integer, primary_key=True)
+    scenario_id: Mapped[int] = mapped_column(
+        ForeignKey("scenarios.id", ondelete="CASCADE"), nullable=False, index=True
+    )
+    name: Mapped[str] = mapped_column(String(255), nullable=False)
+    distribution: Mapped[DistributionType] = mapped_column(
+        SQLEnum(DistributionType), nullable=False
+    )
+    mean_value: Mapped[float | None] = mapped_column(Numeric(18, 4), nullable=True)
+    standard_deviation: Mapped[float | None] = mapped_column(Numeric(18, 4), nullable=True)
+    minimum_value: Mapped[float | None] = mapped_column(Numeric(18, 4), nullable=True)
+    maximum_value: Mapped[float | None] = mapped_column(Numeric(18, 4), nullable=True)
+    unit: Mapped[str | None] = mapped_column(String(32), nullable=True)
+    metadata: Mapped[dict | None] = mapped_column(JSON, nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, server_default=func.now()
+    )
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, server_default=func.now(), onupdate=func.now()
+    )
+
+    scenario: Mapped["Scenario"] = relationship(
+        "Scenario", back_populates="simulation_parameters"
+    )
+
+    def __repr__(self) -> str:  # pragma: no cover
+        return (
+            f"SimulationParameter(id={self.id!r}, scenario_id={self.scenario_id!r}, "
+            f"name={self.name!r})"
+        )