-- §3 / §13.7: add the `retired` soft-delete state to cached_rfcs.
--
-- SQLite cannot ALTER a CHECK constraint in place, so we rebuild the table
-- with the expanded constraint and copy the rows across. cached_rfcs is a
-- §4 cache (reconstructible from Gitea by the reconciler), and nothing
-- holds a foreign key into it, so the rebuild is safe; we preserve the
-- existing rows anyway to avoid a needless full re-read on upgrade.
--
-- The rebuilt table must carry EVERY column cached_rfcs has accumulated,
-- including the ones added by later migrations via ALTER TABLE ADD COLUMN:
--   009_per_rfc_models  -> models_json
--   010_funder          -> funder_login
--   021_proposed_use_case -> proposed_use_case
-- They are appended last (matching the live column order) and copied
-- across explicitly so nothing is dropped.
--
-- The migration runner wraps this file in a single BEGIN/COMMIT, so the
-- swap is atomic.

CREATE TABLE cached_rfcs_new (
    slug                TEXT PRIMARY KEY,
    title               TEXT NOT NULL,
    state               TEXT NOT NULL CHECK (state IN ('super-draft', 'active', 'withdrawn', 'retired')),
    rfc_id              TEXT,                -- 'RFC-NNNN' or NULL (NULL is also valid for an active RFC graduated without a number, §13.2)
    repo                TEXT,                -- 'org/repo' or NULL; always NULL under the meta-only topology (§1)
    proposed_by         TEXT,
    proposed_at         TEXT,
    graduated_at        TEXT,
    graduated_by        TEXT,
    owners_json         TEXT NOT NULL DEFAULT '[]',
    arbiters_json       TEXT NOT NULL DEFAULT '[]',
    tags_json           TEXT NOT NULL DEFAULT '[]',
    body                TEXT,
    body_sha            TEXT,
    last_main_commit_at TEXT,
    last_entry_commit_at TEXT,
    updated_at          TEXT NOT NULL DEFAULT (datetime('now')),
    models_json         TEXT,                -- 009_per_rfc_models
    funder_login        TEXT,                -- 010_funder
    proposed_use_case   TEXT                 -- 021_proposed_use_case
);

INSERT INTO cached_rfcs_new
    (slug, title, state, rfc_id, repo, proposed_by, proposed_at,
     graduated_at, graduated_by, owners_json, arbiters_json, tags_json,
     body, body_sha, last_main_commit_at, last_entry_commit_at, updated_at,
     models_json, funder_login, proposed_use_case)
SELECT
     slug, title, state, rfc_id, repo, proposed_by, proposed_at,
     graduated_at, graduated_by, owners_json, arbiters_json, tags_json,
     body, body_sha, last_main_commit_at, last_entry_commit_at, updated_at,
     models_json, funder_login, proposed_use_case
  FROM cached_rfcs;

DROP TABLE cached_rfcs;
ALTER TABLE cached_rfcs_new RENAME TO cached_rfcs;

CREATE INDEX idx_cached_rfcs_state ON cached_rfcs (state);
CREATE INDEX idx_cached_rfcs_last_active ON cached_rfcs (
    COALESCE(last_main_commit_at, last_entry_commit_at) DESC
);