feat: add Campaign/Compliance domain entities and extract users/audit/data_sources to services (LP-2 through LP-6)

backend/app/domain/entities/campaign.py

@@ -0,0 +1,103 @@
+"""Campaign domain entity with lifecycle validation.
+
+Pure domain logic — no framework imports.
+"""
+
+from __future__ import annotations
+
+import enum
+import uuid
+from dataclasses import dataclass, field
+from typing import Any
+
+from app.domain.errors import BusinessRuleViolation, InvalidStateTransition
+
+
+class CampaignStatus(str, enum.Enum):
+    draft = "draft"
+    active = "active"
+    completed = "completed"
+    archived = "archived"
+
+
+class CampaignType(str, enum.Enum):
+    custom = "custom"
+    apt_emulation = "apt_emulation"
+    kill_chain = "kill_chain"
+    compliance = "compliance"
+
+
+VALID_TRANSITIONS: dict[CampaignStatus, list[CampaignStatus]] = {
+    CampaignStatus.draft: [CampaignStatus.active],
+    CampaignStatus.active: [CampaignStatus.completed],
+    CampaignStatus.completed: [CampaignStatus.archived],
+    CampaignStatus.archived: [],
+}
+
+
+@dataclass
+class CampaignEntity:
+    name: str
+    type: CampaignType = CampaignType.custom
+    status: CampaignStatus = CampaignStatus.draft
+    id: uuid.UUID | None = None
+    description: str | None = None
+    threat_actor_id: uuid.UUID | None = None
+    created_by: uuid.UUID | None = None
+    target_platform: str | None = None
+    tags: list[str] = field(default_factory=list)
+    test_count: int = 0
+
+    def can_transition_to(self, target: CampaignStatus) -> bool:
+        return target in VALID_TRANSITIONS.get(self.status, [])
+
+    def activate(self) -> None:
+        if not self.can_transition_to(CampaignStatus.active):
+            raise InvalidStateTransition(
+                self.status.value, CampaignStatus.active.value,
+                [s.value for s in VALID_TRANSITIONS[self.status]],
+            )
+        if self.test_count == 0:
+            raise BusinessRuleViolation(
+                "Campaign must have at least one test to activate"
+            )
+        self.status = CampaignStatus.active
+
+    def complete(self) -> None:
+        if not self.can_transition_to(CampaignStatus.completed):
+            raise InvalidStateTransition(
+                self.status.value, CampaignStatus.completed.value,
+                [s.value for s in VALID_TRANSITIONS[self.status]],
+            )
+        self.status = CampaignStatus.completed
+
+    def archive(self) -> None:
+        if not self.can_transition_to(CampaignStatus.archived):
+            raise InvalidStateTransition(
+                self.status.value, CampaignStatus.archived.value,
+                [s.value for s in VALID_TRANSITIONS[self.status]],
+            )
+        self.status = CampaignStatus.archived
+
+    def ensure_modifiable(self) -> None:
+        if self.status not in (CampaignStatus.draft, CampaignStatus.active):
+            raise BusinessRuleViolation(
+                f"Cannot modify campaign in '{self.status.value}' state"
+            )
+
+    @classmethod
+    def from_orm(cls, orm: Any) -> CampaignEntity:
+        """Build a CampaignEntity from a SQLAlchemy Campaign model."""
+        test_count = len(getattr(orm, "campaign_tests", None) or [])
+        return cls(
+            id=orm.id,
+            name=orm.name,
+            type=CampaignType(orm.type) if orm.type else CampaignType.custom,
+            status=CampaignStatus(orm.status) if orm.status else CampaignStatus.draft,
+            description=orm.description,
+            threat_actor_id=orm.threat_actor_id,
+            created_by=orm.created_by,
+            target_platform=orm.target_platform,
+            tags=orm.tags or [],
+            test_count=test_count,
+        )