import { type DataSourceInstanceListItem, type DataSourceInstanceSettings, type DataSourceRef, type ScopedVars } from '@grafana/data';
import { type GetDataSourceListFilters } from '../dataSourceSrv';
/**
 * Populate the instance-settings cache from boot data. Intended to be called
 * exactly once at application startup via the `@grafana/runtime/internal` export.
 * In tests, use {@link setDataSourceInstanceSettings} instead.
 *
 * @internal
 */
export declare function initDataSourceInstanceSettings(settings: Record<string, DataSourceInstanceSettings>, defaultDsName: string): void;
/**
 * Test helper — the sanctioned way to seed the instance-settings cache in tests.
 * Fully resets all module state (including runtime and expression data sources),
 * then populates the cache from a clone of `settings` so test fixtures are never
 * mutated. When `defaultDatasourceName` is omitted, the entry flagged with
 * `isDefault: true` becomes the default. Should only be called from tests.
 *
 * @internal
 */
export declare function setDataSourceInstanceSettings(settings: Record<string, DataSourceInstanceSettings>, defaultDatasourceName?: string): void;
export declare function reloadDataSourceInstanceSettings(): Promise<void>;
interface SyncDataSourceSettings {
    datasources: Record<string, DataSourceInstanceSettings>;
    defaultDatasource: string;
}
/**
 * Sync the instance-settings cache from an already-fetched `/api/frontend/settings`
 * payload, without issuing another backend request. Built-in (e.g. expression) and
 * runtime data sources survive because `populateMaps` re-applies them.
 *
 * Transition-period helper: while both the legacy `DataSourceSrv` and the new async
 * datasource APIs exist, `DataSourceSrv.reload()` calls this so a single fetch updates
 * both caches. Remove once `DataSourceSrv` is gone.
 *
 * @internal
 */
export declare function syncDataSourceInstanceSettings(settings: SyncDataSourceSettings): void;
/**
 * Look up the instance settings for a data source from the in-memory cache
 * populated at boot. Call {@link reloadDataSourceInstanceSettings} to refresh
 * the cache from the backend.
 *
 * `scopedVars` are used when `ref` contains a template variable (e.g. `$ds`).
 *
 * @public
 */
export declare function getDataSourceInstanceSettings(ref?: DataSourceRef | string | null, scopedVars?: ScopedVars): Promise<DataSourceInstanceSettings | undefined>;
/**
 * Filters for {@link getDataSourceInstanceList} and {@link useDataSourceInstanceList}.
 *
 * Identical to {@link GetDataSourceListFilters} except the `filter` callback receives a
 * {@link DataSourceInstanceListItem} instead of the full {@link DataSourceInstanceSettings}.
 * This reflects the long-term data model: the list API will only expose the slim item shape,
 * so filter callbacks must not rely on settings-specific fields such as `jsonData` or `url`.
 *
 * @public
 */
export interface GetDataSourceInstanceListFilters extends Omit<GetDataSourceListFilters, 'filter'> {
    /** Apply a function to filter the list. Receives a slim {@link DataSourceInstanceListItem}. */
    filter?: (item: DataSourceInstanceListItem) => boolean;
}
/**
 * Search and filter data sources from the in-memory cache, returning a
 * lightweight view of each match. The heavy per-instance settings are not
 * included — fetch them on demand via {@link getDataSourceInstanceSettings}.
 *
 * @public
 */
export declare function getDataSourceInstanceList(filters?: GetDataSourceInstanceListFilters): Promise<DataSourceInstanceListItem[]>;
/**
 * Resolve the default data source instance of a given type. Returns the instance flagged
 * as default, otherwise the first instance of that type, or `undefined` when none exist.
 *
 * Covers the common "get my data source" pattern (`list.find(ds => ds.isDefault) ?? list[0]`)
 * without exposing the full list. The heavy per-instance settings are not included — fetch
 * them on demand via {@link getDataSourceInstanceSettings}.
 *
 * @public
 */
export declare function getDefaultDataSourceInstance(type: string): Promise<DataSourceInstanceListItem | undefined>;
/**
 * Check whether at least one data source instance of the given type is installed.
 *
 * Covers presence checks (`getList({ type }).length > 0`) without returning a list.
 *
 * @public
 */
export declare function hasDataSourceInstance(type: string): Promise<boolean>;
/**
 * Register the instance settings for a runtime data source so it is returned
 * by future lookups. Throws if the uid is already in use.
 *
 * @internal
 */
export declare function upsertRuntimeDataSourceInstanceSettings(settings: DataSourceInstanceSettings): void;
/**
 * Test helper — resets all module state. Should only be called from tests.
 *
 * @internal
 */
export declare function _resetForTests(): void;
export {};