feat(PORTFOLIO-001): add position-level portfolio entries

app/models/workspace.py

@@ -2,9 +2,10 @@ from __future__ import annotations
 
 import re
 from pathlib import Path
-from uuid import uuid4
+from uuid import UUID, uuid4
 
 from app.models.portfolio import PortfolioConfig, PortfolioRepository, build_default_portfolio_config
+from app.models.position import Position
 
 WORKSPACE_COOKIE = "workspace_id"
 _WORKSPACE_ID_RE = re.compile(
@@ -63,6 +64,69 @@ class WorkspaceRepository:
             raise ValueError("workspace_id must be a UUID4 string")
         PortfolioRepository(self._portfolio_path(workspace_id)).save(config)
 
+    def add_position(self, workspace_id: str, position: Position) -> None:
+        """Add a position to the workspace portfolio."""
+        if not self.is_valid_workspace_id(workspace_id):
+            raise ValueError("workspace_id must be a UUID4 string")
+        config = self.load_portfolio_config(workspace_id)
+        # Use object.__setattr__ because positions is in a frozen dataclass
+        object.__setattr__(config, "positions", list(config.positions) + [position])
+        self.save_portfolio_config(workspace_id, config)
+
+    def remove_position(self, workspace_id: str, position_id: UUID) -> None:
+        """Remove a position from the workspace portfolio."""
+        if not self.is_valid_workspace_id(workspace_id):
+            raise ValueError("workspace_id must be a UUID4 string")
+        config = self.load_portfolio_config(workspace_id)
+        updated_positions = [p for p in config.positions if p.id != position_id]
+        object.__setattr__(config, "positions", updated_positions)
+        self.save_portfolio_config(workspace_id, config)
+
+    def update_position(
+        self,
+        workspace_id: str,
+        position_id: UUID,
+        updates: dict[str, object],
+    ) -> None:
+        """Update a position's fields."""
+        if not self.is_valid_workspace_id(workspace_id):
+            raise ValueError("workspace_id must be a UUID4 string")
+        config = self.load_portfolio_config(workspace_id)
+        updated_positions = []
+        for pos in config.positions:
+            if pos.id == position_id:
+                # Create updated position (Position is frozen, so create new instance)
+                update_kwargs: dict[str, object] = {}
+                for key, value in updates.items():
+                    if key in {"id", "created_at"}:
+                        continue  # Skip immutable fields
+                    update_kwargs[key] = value
+                # Use dataclass replace-like pattern
+                pos_dict = pos.to_dict()
+                pos_dict.update(update_kwargs)
+                updated_positions.append(Position.from_dict(pos_dict))
+            else:
+                updated_positions.append(pos)
+        object.__setattr__(config, "positions", updated_positions)
+        self.save_portfolio_config(workspace_id, config)
+
+    def get_position(self, workspace_id: str, position_id: UUID) -> Position | None:
+        """Get a specific position by ID."""
+        if not self.is_valid_workspace_id(workspace_id):
+            raise ValueError("workspace_id must be a UUID4 string")
+        config = self.load_portfolio_config(workspace_id)
+        for pos in config.positions:
+            if pos.id == position_id:
+                return pos
+        return None
+
+    def list_positions(self, workspace_id: str) -> list[Position]:
+        """List all positions in the workspace portfolio."""
+        if not self.is_valid_workspace_id(workspace_id):
+            raise ValueError("workspace_id must be a UUID4 string")
+        config = self.load_portfolio_config(workspace_id)
+        return list(config.positions)
+
     def _portfolio_path(self, workspace_id: str) -> Path:
         return self.base_path / workspace_id / "portfolio_config.json"