import { type JSONSchema } from 'json-schema-to-ts';
import { type JsonValue } from 'type-fest';
/**
 * The JSON Schema type used by `ViraJsonForm`. Re-exported from `json-schema-to-ts` so that callers
 * can pass standard JSON Schema objects.
 *
 * @category Internal
 */
export type ViraJsonSchema = JSONSchema;
/**
 * A non-boolean JSON Schema object. Boolean schemas (`true` / `false`) are valid JSON Schemas but
 * don't constrain the editor in useful ways, so we normalize them away during traversal.
 *
 * @category Internal
 */
export type ViraJsonSchemaObject = Exclude<ViraJsonSchema, boolean>;
/**
 * The JSON types supported by `ViraJsonForm`.
 *
 * @category Internal
 */
export declare enum ViraJsonType {
    String = "string",
    Number = "number",
    Integer = "integer",
    Boolean = "boolean",
    Null = "null",
    Object = "object",
    Array = "array"
}
/**
 * Human-friendly labels for each {@link ViraJsonType}.
 *
 * @category Internal
 */
export declare const viraJsonTypeLabels: Readonly<Record<ViraJsonType, string>>;
/**
 * Classifies a JSON value's runtime type. Note that {@link ViraJsonType.Integer} is never returned;
 * it only appears in schemas. All numbers (whole or fractional) classify as
 * {@link ViraJsonType.Number}, since JSON has no separate integer type at runtime.
 *
 * @category Internal
 */
export declare function getJsonType(value: JsonValue | undefined): ViraJsonType;
/**
 * Normalizes a schema to a non-boolean object form. `true` becomes an unconstrained schema (`{}`),
 * `false` becomes `undefined` (nothing is allowed; treated as "no schema available").
 *
 * @category Internal
 */
export declare function normalizeSchema(schema: ViraJsonSchema | undefined): ViraJsonSchemaObject | undefined;
/**
 * Context used while resolving `$ref` entries against a root schema's `$defs` (or `definitions`)
 * map. A stack of seen refs prevents infinite recursion from cyclical schemas.
 *
 * @category Internal
 */
export type SchemaResolveContext = {
    root: ViraJsonSchemaObject | undefined;
    seenRefs: ReadonlySet<string>;
};
/** @category Internal */
export declare function createResolveContext(schema: ViraJsonSchema | undefined): SchemaResolveContext;
/**
 * Resolves a schema through `$ref` (via its root's `$defs`/`definitions`), returning the resolved
 * schema and an updated resolve context. Non-ref schemas are returned as-is.
 *
 * @category Internal
 */
export declare function resolveSchema(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): {
    resolved: ViraJsonSchemaObject | undefined;
    context: SchemaResolveContext;
};
/**
 * Flattens `anyOf` / `oneOf` branches into a single list of non-union schemas so that the editor
 * can treat them uniformly.
 *
 * @category Internal
 */
export declare function expandSchemaBranches(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): ReadonlyArray<ViraJsonSchemaObject>;
/**
 * Computes the set of JSON types that a given schema allows.
 *
 * @category Internal
 */
export declare function getAllowedJsonTypes(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): ReadonlyArray<ViraJsonType>;
/** @category Internal */
export declare function createDefaultForJsonType(type: ViraJsonType): JsonValue;
/**
 * Picks the first schema branch whose `type` contains (or is) the given JSON type. Used to narrow
 * the schema when traversing into a concrete value.
 *
 * @category Internal
 */
export declare function pickBranchForType(schema: ViraJsonSchema | undefined, valueType: ViraJsonType, context: SchemaResolveContext): ViraJsonSchemaObject | undefined;
/**
 * Finds the sub-schema for a given object property key, considering `properties`,
 * `patternProperties`, and `additionalProperties`.
 *
 * @category Internal
 */
export declare function getPropertySchema(parentSchema: ViraJsonSchema | undefined, key: string, context: SchemaResolveContext): ViraJsonSchema | undefined;
/**
 * Finds the sub-schema for an array item at a given index, considering tuple `items` arrays and
 * `additionalItems` fallbacks.
 *
 * @category Internal
 */
export declare function getItemSchema(parentSchema: ViraJsonSchema | undefined, index: number, context: SchemaResolveContext): ViraJsonSchema | undefined;
/**
 * Returns the schema used when appending a new item to an array. Falls back to `additionalItems`
 * when `items` is a tuple array and the new index is beyond the tuple's length.
 *
 * @category Internal
 */
export declare function getNewItemSchema(parentSchema: ViraJsonSchema | undefined, currentLength: number, context: SchemaResolveContext): ViraJsonSchema | undefined;
/**
 * Returns the schema used when adding an arbitrary new field to an object. When no schema is
 * provided at all the editor is unconstrained, so additions are allowed; once a schema is provided,
 * additions are only allowed when the schema explicitly opts in via `additionalProperties: true` or
 * an `additionalProperties` sub-schema. This is stricter than JSON Schema's `true` default — UI
 * authors must opt in.
 *
 * @category Internal
 */
export declare function getAdditionalPropertiesSchema(parentSchema: ViraJsonSchema | undefined, context: SchemaResolveContext): {
    allowed: boolean;
    schema: ViraJsonSchema | undefined;
};
/**
 * Returns the `enum` values defined by any resolved branch of a schema. Aggregates across
 * `anyOf`/`oneOf` branches and includes `const` values so the editor can offer them as a select.
 *
 * @category Internal
 */
export declare function getEnumValues(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): ReadonlyArray<JsonValue> | undefined;
/**
 * Returns the list of required property names declared by the object branch of a schema.
 *
 * @category Internal
 */
export declare function getRequiredProperties(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): ReadonlyArray<string>;
/**
 * Returns the `properties` map declared by the object branch of a schema, or an empty record when
 * none is defined.
 *
 * @category Internal
 */
export declare function getDefinedProperties(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): Readonly<Record<string, ViraJsonSchema>>;
/**
 * Reads the title of a schema's first resolved branch (for display purposes).
 *
 * @category Internal
 */
export declare function getSchemaTitle(schema: ViraJsonSchema | undefined, context: SchemaResolveContext): string | undefined;
/**
 * Validates a JSON value against the (loose) JSON Schema subset supported by `ViraJsonForm`.
 * Returns a list of human-readable error messages; an empty array means the value is valid. Only
 * the constraints understood by the editor (`type`, `required`, `properties`, `additionalProperties
 * = false`, `items`, `enum`, `const`, `anyOf`, `oneOf`, `$ref`) are checked.
 *
 * @category Internal
 */
export declare function validateAgainstSchema(value: JsonValue, schema: ViraJsonSchema | undefined): ReadonlyArray<string>;
/**
 * Type of a JSON path element. `string` selects an object key; `number` selects an array index.
 *
 * @category Internal
 */
export type ViraJsonPath = ReadonlyArray<string | number>;
/** @category Internal */
export declare function pathToKey(path: ViraJsonPath): string;
/**
 * Returns a new JSON value where the value at `path` has been replaced with `newValue`.
 *
 * @category Internal
 */
export declare function setValueAtPath(root: JsonValue, path: ViraJsonPath, newValue: JsonValue): JsonValue;
/**
 * Returns a new JSON value where the value at `path` has been removed. If `path` targets an object
 * key, the key is deleted; if it targets an array index, the item is spliced out.
 *
 * @category Internal
 */
export declare function deleteValueAtPath(root: JsonValue, path: ViraJsonPath): JsonValue;