-- Make client request IDs idempotent within an account, not globally.
ALTER TABLE usage_records
    DROP FOREIGN KEY fk_usage_records_provider_request,
    DROP INDEX uq_usage_records_request_meter,
    ADD COLUMN account_id VARCHAR(36) CHARACTER SET ascii COLLATE ascii_bin NULL AFTER id;

UPDATE usage_records ur
JOIN provider_requests pr ON pr.request_id = ur.request_id
SET ur.account_id = pr.account_id;

ALTER TABLE usage_records
    MODIFY account_id VARCHAR(36) CHARACTER SET ascii COLLATE ascii_bin NOT NULL;

-- Normalize every legacy value before installing the binary status column and
-- stricter CHECK. Unknown historical states are held for manual review rather
-- than making a non-transactional MySQL migration fail halfway through.
UPDATE provider_requests
SET status = CASE UPPER(status)
    WHEN 'SUCCEEDED' THEN 'SETTLED'
    WHEN 'FAILED' THEN 'MANUAL_REVIEW'
    WHEN 'CLAIMED' THEN 'CLAIMED'
    WHEN 'STARTED' THEN 'STARTED'
    WHEN 'SETTLEMENT_PENDING' THEN 'SETTLEMENT_PENDING'
    WHEN 'SETTLED' THEN 'SETTLED'
    WHEN 'RELEASED' THEN 'RELEASED'
    WHEN 'MANUAL_REVIEW' THEN 'MANUAL_REVIEW'
    ELSE 'MANUAL_REVIEW'
END;

ALTER TABLE provider_requests
    ADD COLUMN reservation_id CHAR(36) NULL AFTER account_id,
    ADD COLUMN usage_meter VARCHAR(32) NULL AFTER provider_request_id,
    ADD COLUMN usage_units BIGINT UNSIGNED NULL AFTER usage_meter,
    ADD COLUMN usage_input_units BIGINT UNSIGNED NULL AFTER usage_units,
    ADD COLUMN usage_output_units BIGINT UNSIGNED NULL AFTER usage_input_units,
    MODIFY COLUMN status VARCHAR(24) CHARACTER SET ascii COLLATE ascii_bin NOT NULL,
    DROP PRIMARY KEY,
    ADD PRIMARY KEY (account_id, request_id),
    ADD UNIQUE KEY uq_provider_requests_reservation (reservation_id),
    ADD INDEX idx_provider_requests_status_created (status, created_at),
    ADD CONSTRAINT chk_provider_request_status CHECK (
        status IN (
            'CLAIMED',
            'STARTED',
            'SETTLEMENT_PENDING',
            'SETTLED',
            'RELEASED',
            'MANUAL_REVIEW'
        )
    );

ALTER TABLE usage_records
    ADD UNIQUE KEY uq_usage_records_account_request_meter (account_id, request_id, meter),
    ADD CONSTRAINT fk_usage_records_provider_request
        FOREIGN KEY (account_id, request_id)
        REFERENCES provider_requests (account_id, request_id)
        ON DELETE CASCADE;

-- A rotated refresh row points to its replacement. RESTRICT can block the
-- account -> grant -> refresh cascade when an account is deleted.
ALTER TABLE gateway_refresh_tokens
    DROP FOREIGN KEY fk_gateway_refresh_replacement,
    ADD CONSTRAINT fk_gateway_refresh_replacement
        FOREIGN KEY (replaced_by_id) REFERENCES gateway_refresh_tokens (id)
        ON DELETE SET NULL;