-- Phase 5 / M3 (v1.2 Hierarchies): multi-repo single-owner ownership (§7).
--
-- A group node is authoritatively MANAGED by at most one project-root (the
-- repo whose manifest declares it as something it applies, not merely
-- references). `groups.owner_project` has carried this seam since 0047 as an
-- inert, FK-less UUID. M3 makes it a real reference: a `projects` table keyed
-- by a stable, gitignored project key the CLI mints in `.picloud/`, and a
-- foreign key from `groups.owner_project` to it.
--
-- Ownership is recorded at GROUP granularity; apps inherit their owning project
-- from their group (apps are never claimed directly). A NULL `owner_project`
-- means the node is UI/API-owned — no manifest fights it (§7.5). First apply
-- claims; a second project's apply to an owned node is refused unless
-- `--takeover` (group-admin gated). Ownership ⟂ RBAC: owning the manifest does
-- NOT grant write — the actor still needs the usual group capabilities (§7.4).
--
-- ON DELETE SET NULL: deleting a project row (not something the platform does
-- today) reverts its nodes to UI-owned rather than cascading away real groups.

CREATE TABLE projects (
    id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    -- Stable, opaque key minted by `pic init` and persisted (gitignored) in the
    -- repo's `.picloud/`. The CLI presents it on every tree apply; the server
    -- maps it to this row (upsert-by-key), so the same repo keeps the same
    -- project identity across clones/CI without committing any server id.
    key        TEXT NOT NULL UNIQUE,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

-- Promote the inert `groups.owner_project` (0047) to a real FK now that the
-- referent exists. Existing rows are all NULL (no projects yet), so this adds
-- no validation burden.
ALTER TABLE groups
    ADD CONSTRAINT groups_owner_project_fkey
    FOREIGN KEY (owner_project) REFERENCES projects(id) ON DELETE SET NULL;

-- The ownership reconcile reads "which groups does project P own?" (to find
-- owned-but-undeclared nodes for structural prune) and "who owns group G?".
CREATE INDEX groups_owner_project_idx ON groups (owner_project);