"""Content Engine domain models. Model inventory --------------- ContentCategory — hierarchical category tree for content items. ContentItem — unified content entity (14 content types). ContentVersion — immutable snapshot on publish. Design decisions ---------------- * Every business entity extends TenantScopedModel (tenant + org_node FKs). * UUIDModel exposes public_id for external identifiers. * AuditedModel adds created_by/updated_by auto-populated from RequestContext. * SoftDeleteModel protects content from accidental hard-delete. * VersionedModel provides optimistic concurrency control. * ContentItem.content_type is a TextChoices discriminator — NOT separate tables. * Attachments, Comments, Tags, Custom Fields: reuse platform_core (GenericFK). * Workflow: ContentItem.workflow_instance FK to WorkflowInstance. * Approval: via Approval Engine (ApprovalRequest linked to ContentItem). """ from __future__ import annotations from typing import ClassVar from django.conf import settings from django.db import models from django.utils.translation import gettext_lazy as _ from simorgh.core.models import ( AuditedModel, OrderedModel, ScopedSoftDeleteManager, SoftDeleteModel, TenantScopedModel, UUIDModel, VersionedModel, ) class ContentType(models.TextChoices): DEV_DOC = "dev_doc", _("Developer Documentation") USER_MANUAL = "user_manual", _("User Manual") ADMIN_MANUAL = "admin_manual", _("Admin Manual") ARCH_DOC = "arch_doc", _("Architecture Documentation") API_DOC = "api_doc", _("API Documentation") KB_ARTICLE = "kb_article", _("Knowledge Base Article") FAQ = "faq", _("FAQ") PROCEDURE = "procedure", _("Procedure") POLICY = "policy", _("Policy") ARTICLE = "article", _("Article") NEWS = "news", _("News") ANNOUNCEMENT = "announcement", _("Announcement") RELEASE_NOTES = "release_notes", _("Release Notes") CHANGELOG = "changelog", _("Changelog") class ContentVisibility(models.TextChoices): PUBLIC = "public", _("Public") INTERNAL = "internal", _("Internal — authenticated users") PRIVATE = "private", _("Private — author only") class ContentStatus(models.TextChoices): DRAFT = "draft", _("Draft") REVIEW = "review", _("In Review") APPROVED = "approved", _("Approved") PUBLISHED = "published", _("Published") ARCHIVED = "archived", _("Archived") # --------------------------------------------------------------------------- # ContentCategory # --------------------------------------------------------------------------- class ContentCategory(UUIDModel, TenantScopedModel, OrderedModel): """Hierarchical category tree for content items.""" parent = models.ForeignKey( "self", on_delete=models.SET_NULL, null=True, blank=True, related_name="children", verbose_name=_("parent category"), ) name = models.CharField(_("name"), max_length=200) slug = models.SlugField(_("slug"), max_length=200) description = models.TextField(_("description"), blank=True, default="") icon = models.CharField(_("icon"), max_length=50, blank=True, default="") is_active = models.BooleanField(_("active"), default=True, db_index=True) class Meta: verbose_name = _("content category") verbose_name_plural = _("content categories") unique_together = [("tenant", "slug")] indexes: ClassVar[list[models.Index]] = [ models.Index(fields=("tenant", "parent")), models.Index(fields=("tenant", "is_active")), ] def __str__(self) -> str: return self.name # --------------------------------------------------------------------------- # ContentItem # --------------------------------------------------------------------------- class ContentItem(UUIDModel, TenantScopedModel, AuditedModel, SoftDeleteModel, VersionedModel): """Unified content model — all content types in one table.""" title = models.CharField(_("title"), max_length=500) slug = models.SlugField(_("slug"), max_length=500) content_type = models.CharField( _("content type"), max_length=30, choices=ContentType.choices, db_index=True, ) category = models.ForeignKey( ContentCategory, on_delete=models.SET_NULL, null=True, blank=True, related_name="items", verbose_name=_("category"), ) body = models.TextField(_("body"), blank=True, default="") excerpt = models.TextField(_("excerpt"), blank=True, default="", max_length=2000) status = models.CharField( _("status"), max_length=20, choices=ContentStatus.choices, default=ContentStatus.DRAFT, db_index=True, ) visibility = models.CharField( _("visibility"), max_length=12, choices=ContentVisibility.choices, default=ContentVisibility.INTERNAL, ) author = models.ForeignKey( settings.AUTH_USER_MODEL, on_delete=models.PROTECT, related_name="authored_content", verbose_name=_("author"), ) published_at = models.DateTimeField(_("published at"), null=True, blank=True, db_index=True) archived_at = models.DateTimeField(_("archived at"), null=True, blank=True) # SEO / metadata meta_title = models.CharField(_("meta title"), max_length=200, blank=True, default="") meta_description = models.TextField(_("meta description"), blank=True, default="", max_length=500) meta_keywords = models.CharField(_("meta keywords"), max_length=500, blank=True, default="") # Denormalized counters (updated via F() expressions) view_count = models.PositiveIntegerField(_("view count"), default=0) helpful_count = models.PositiveIntegerField(_("helpful count"), default=0) not_helpful_count = models.PositiveIntegerField(_("not helpful count"), default=0) # AI / Semantic metadata ai_description = models.TextField(_("AI description"), blank=True, default="") ai_semantic_type = models.CharField(_("AI semantic type"), max_length=100, blank=True, default="") ai_summary = models.TextField(_("AI summary"), blank=True, default="") # Related content (soft refs — JSON array of public_id UUIDs) related_content = models.JSONField(_("related content"), default=list, blank=True) # Workflow instance link workflow_instance = models.ForeignKey( "platform_workflow.WorkflowInstance", on_delete=models.SET_NULL, null=True, blank=True, related_name="+", verbose_name=_("workflow instance"), ) # Workspace context (nullable — workspace-scoped content) workspace = models.ForeignKey( "platform_workspaces.Workspace", on_delete=models.SET_NULL, null=True, blank=True, related_name="content_items", verbose_name=_("workspace"), ) objects = ScopedSoftDeleteManager() class Meta: verbose_name = _("content item") verbose_name_plural = _("content items") unique_together = [("tenant", "slug")] indexes: ClassVar[list[models.Index]] = [ models.Index(fields=("tenant", "content_type")), models.Index(fields=("tenant", "status")), models.Index(fields=("tenant", "category")), models.Index(fields=("tenant", "author")), models.Index(fields=("tenant", "published_at")), models.Index(fields=("tenant", "content_type", "status")), models.Index(fields=("tenant", "visibility")), ] ordering = ["-published_at", "-created_at"] def __str__(self) -> str: return f"{self.get_content_type_display()}: {self.title} [{self.status}]" # --------------------------------------------------------------------------- # ContentVersion # --------------------------------------------------------------------------- class ContentVersion(UUIDModel, TenantScopedModel): """Immutable snapshot of content at publish time.""" content_item = models.ForeignKey( ContentItem, on_delete=models.CASCADE, related_name="versions", verbose_name=_("content item"), ) version = models.PositiveIntegerField(_("version number")) title = models.CharField(_("title"), max_length=500) body = models.TextField(_("body")) excerpt = models.TextField(_("excerpt"), blank=True, default="", max_length=2000) status = models.CharField(_("status at snapshot"), max_length=20, choices=ContentStatus.choices) changed_by = models.ForeignKey( settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, null=True, blank=True, related_name="+", verbose_name=_("changed by"), ) change_summary = models.CharField(_("change summary"), max_length=500, blank=True, default="") created_at = models.DateTimeField(_("created at"), auto_now_add=True) class Meta: verbose_name = _("content version") verbose_name_plural = _("content versions") unique_together = [("content_item", "version")] ordering = ["-version"] def __str__(self) -> str: return f"{self.content_item_id} v{self.version}"