feat(podcasts): add lifecycle migration

surfsense_backend/alembic/versions/156_evolve_podcasts_lifecycle.py

@@ -0,0 +1,92 @@
+"""evolve podcasts: expand status lifecycle and add brief/transcript/storage columns
+
+Revision ID: 156
+Revises: 155
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+
+revision: str = "156"
+down_revision: str | None = "155"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    # Retype the status enum by swapping in a fresh type and casting existing
+    # rows. The legacy transient value 'generating' maps onto 'rendering'.
+    op.execute("ALTER TYPE podcast_status RENAME TO podcast_status_old;")
+    op.execute(
+        """
+        CREATE TYPE podcast_status AS ENUM (
+            'pending', 'awaiting_brief', 'drafting', 'awaiting_review',
+            'rendering', 'ready', 'failed', 'cancelled'
+        );
+        """
+    )
+    op.execute("ALTER TABLE podcasts ALTER COLUMN status DROP DEFAULT;")
+    op.execute(
+        """
+        ALTER TABLE podcasts
+            ALTER COLUMN status TYPE podcast_status
+            USING (
+                CASE status::text
+                    WHEN 'generating' THEN 'rendering'
+                    ELSE status::text
+                END
+            )::podcast_status;
+        """
+    )
+    op.execute("ALTER TABLE podcasts ALTER COLUMN status SET DEFAULT 'pending';")
+    op.execute("DROP TYPE podcast_status_old;")
+
+    op.execute("ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS source_content TEXT;")
+    op.execute("ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS spec JSONB;")
+    op.execute(
+        "ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS spec_version "
+        "INTEGER NOT NULL DEFAULT 1;"
+    )
+    op.execute(
+        "ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS storage_backend VARCHAR(32);"
+    )
+    op.execute("ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS storage_key TEXT;")
+    op.execute("ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS duration_seconds INTEGER;")
+    op.execute("ALTER TABLE podcasts ADD COLUMN IF NOT EXISTS error TEXT;")
+
+
+def downgrade() -> None:
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS error;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS duration_seconds;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS storage_key;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS storage_backend;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS spec_version;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS spec;")
+    op.execute("ALTER TABLE podcasts DROP COLUMN IF EXISTS source_content;")
+
+    # Collapse the expanded lifecycle back onto the original four values.
+    op.execute("ALTER TYPE podcast_status RENAME TO podcast_status_new;")
+    op.execute(
+        "CREATE TYPE podcast_status AS ENUM "
+        "('pending', 'generating', 'ready', 'failed');"
+    )
+    op.execute("ALTER TABLE podcasts ALTER COLUMN status DROP DEFAULT;")
+    op.execute(
+        """
+        ALTER TABLE podcasts
+            ALTER COLUMN status TYPE podcast_status
+            USING (
+                CASE status::text
+                    WHEN 'awaiting_brief' THEN 'pending'
+                    WHEN 'drafting' THEN 'generating'
+                    WHEN 'awaiting_review' THEN 'generating'
+                    WHEN 'rendering' THEN 'generating'
+                    WHEN 'cancelled' THEN 'failed'
+                    ELSE status::text
+                END
+            )::podcast_status;
+        """
+    )
+    op.execute("ALTER TABLE podcasts ALTER COLUMN status SET DEFAULT 'ready';")
+    op.execute("DROP TYPE podcast_status_new;")