package creator

import (
	"context"
	"database/sql"
	"errors"
	"time"
)

// 同步互斥租约：与作品/评论采集共用 creator_collection_checkpoint（统一租约模式），
// collection_kind='sync'，窗口列填 now() 占位（同步租约不跟踪采集窗口）。
func (s *Store) ClaimSourceSync(ctx context.Context, sourceType, sourceID string) (string, error) {
	if sourceType != SourceOwned && sourceType != SourceCompetitor || sourceID == "" {
		return "", ErrInvalid
	}
	token := newID("lease")
	now := time.Now().UTC()
	var claimed string
	err := s.db.QueryRowContext(ctx, `
		INSERT INTO creator_collection_checkpoint
			(source_type, source_id, collection_kind, cursor, window_start, window_end, status, lease_token, lease_until, last_error)
		VALUES ($1, $2, 'sync', '', $3, $3, 'running', $4, $3::timestamptz + interval '10 minutes', '')
		ON CONFLICT (source_type, source_id, collection_kind) DO UPDATE SET
			status = 'running', lease_token = EXCLUDED.lease_token, lease_until = EXCLUDED.lease_until
		WHERE creator_collection_checkpoint.lease_until IS NULL
		   OR creator_collection_checkpoint.lease_until <= now()
		RETURNING lease_token`, sourceType, sourceID, now, token).Scan(&claimed)
	if errors.Is(err, sql.ErrNoRows) {
		return "", ErrConflict
	}
	if err != nil {
		return "", databaseError(err)
	}
	return claimed, nil
}

func (s *Store) ReleaseSourceSync(ctx context.Context, sourceType, sourceID, token string) error {
	if sourceType != SourceOwned && sourceType != SourceCompetitor || sourceID == "" || token == "" {
		return ErrInvalid
	}
	result, err := s.db.ExecContext(ctx, `
		DELETE FROM creator_collection_checkpoint
		WHERE source_type = $1 AND source_id = $2 AND collection_kind = 'sync' AND lease_token = $3`,
		sourceType, sourceID, token)
	if err != nil {
		return databaseError(err)
	}
	if rows, err := result.RowsAffected(); err != nil {
		return err
	} else if rows != 1 {
		return ErrConflict
	}
	return nil
}