-- Offers to move a mod from its owner's repo to another account's, and how
-- far each accepted one has got.

-- A record can't change repos, so a transfer copies the listing and its
-- versions into the recipient's repo, then deletes the originals. Each step
-- is recorded before it's taken, so an accept that fails partway resumes
-- where it stopped rather than copying twice.
CREATE TABLE IF NOT EXISTS mod_transfer
(
    id            INTEGER PRIMARY KEY,
    sender_did    TEXT NOT NULL,
    listing_rkey  TEXT NOT NULL,
    -- The mod's slug when it was offered, so its old address can redirect.
    slug          TEXT NOT NULL,
    recipient_did TEXT NOT NULL,
    created_at    TEXT NOT NULL,
    -- An offer nobody accepted by now is void.
    expires_at    TEXT NOT NULL,

    -- Where the copy goes in the recipient's repo, chosen when they first
    -- accept. Once set, the offer no longer expires and can't be declined.
    new_rkey TEXT,
    new_slug TEXT,
    -- When the copy was finished and the original hidden.
    accepted_at TEXT,
    -- When the originals were deleted from the sender's repo, which only the
    -- sender's own session can do.
    originals_deleted_at TEXT
);

-- One offer per mod at a time.
CREATE UNIQUE INDEX IF NOT EXISTS mod_transfer_listing ON mod_transfer (sender_did, listing_rkey);
CREATE INDEX IF NOT EXISTS mod_transfer_recipient ON mod_transfer (recipient_did);
CREATE INDEX IF NOT EXISTS mod_transfer_slug ON mod_transfer (sender_did, slug);

-- The copy of each version of a transferred mod, minted before it's written.
CREATE TABLE IF NOT EXISTS mod_transfer_version
(
    transfer_id INTEGER NOT NULL REFERENCES mod_transfer (id) ON DELETE CASCADE,
    old_rkey    TEXT NOT NULL,
    new_rkey    TEXT NOT NULL,
    -- Where the version's deliverable is copied to, if it had one.
    new_object_key TEXT,

    PRIMARY KEY (transfer_id, old_rkey)
);