import type { Field, Operator, SchemaBase } from './dsl.js';
import type { ValueExpr } from './expr.js';
import type { FrontAppSchema, ProjectApiSchema } from './project.js';
/** One AND-combined criterion: a column plus its comparison operator. */
export interface FilterCondition {
    /** Column to compare (any table — cross-table filters are allowed). */
    field: Field;
    /** Comparison operator; defaults to 'eq'. */
    op?: Operator;
    /** Right side of the comparison. Absent = the args parameter named after
     *  the column (existing semantics); present = an explicit value expression
     *  (column-vs-column, literal, computation). */
    right?: ValueExpr;
    /** Required (default) or optional criterion. A filter has one semantics:
     *  dao filters are required (missing criteria = error), page filters are
     *  optional (missing criteria = no WHERE). Declared by the filter author. */
    optional?: boolean;
}
/** Query filter: AND-combined conditions plus an optional keyword search. */
export interface FilterSchema extends SchemaBase {
    type: 'filter';
    /** The backend api module this filter belongs to (shared instance from
     *  project.config.ts apis). Filters are backend-side, so storage is
     *  filter_schema/{api.name}/{app.name}/filter/ — app unset = the api-level
     *  common domain layer, stored at filter_schema/{api.name}/common/filter/. */
    api: ProjectApiSchema;
    /** The frontend app this filter belongs to (shared instance from project.config).
     *  Unset = api-level common domain filter shared by all modules of the api. */
    app?: FrontAppSchema;
    /** AND-combined conditions (may be empty when keyword is present). */
    conditions: FilterCondition[];
    /** Fuzzy keyword search: one input value matched against multiple columns
     *  via OR-like. Presence drives the keyword query endpoint. */
    keyword?: {
        columns: Field[];
    };
}
export declare function defineFilter(options: {
    name: string;
    api: ProjectApiSchema;
    app?: FrontAppSchema;
    conditions?: FilterCondition[];
    keyword?: {
        columns: Field[];
    };
    description?: string;
}): FilterSchema;