/**
* Combines multiple qualifiers into a single object.
 * @returns the combined qualifier
 * @throws Error if any of the qualifiers contain intersecting property names
*/
const and = <A, B, C, D>(qualA: A,  qualB: B,  qualC?: C,  qualD?: D): =>  A & B & (C | object) & (D | object);

/**
 * A qualifier that identifies entities based on a freetext search string.
 */
type FreetextQualifier = Readonly<{ freetext: string }>;

/**
 * Builds a qualifier for finding entities by the given freetext string.
 * @param freetext the text to search with
 * @returns the qualifier
 * @throws Error if the search string is not provided or is empty
 */
const byFreetext(freetext: string) => FreetextQualifier;

/**
* Returns `true` if the given qualifier is a {@link FreetextQualifier} otherwise `false`.
* @param qualifier the qualifier to check
* @returns `true` if the given type is a {@link FreetextQualifier}, otherwise `false`.
*/
const isFreetextQualifier = (qualifier: unknown) => qualifier is FreetextQualifier;

  // Move contents of libs/contact.ts into this file
namespace v1 {
  // Contact interface should go in the v1 namespace with the following documentation:
  /**
   * Immutable data about a contact.
   */

  /**
   * Immutable data about a contact, including the full records of the parent lineage.
   */
  interface ContactWithLineage extends Contact {
    readonly parent?: ContactWithLineage | NormalizedParent,
  }

  // New REST api: /api/v1/contact
  /**
   * Returns a function for retrieving a contact from the given data context.
   * @param context the current data context
   * @returns a function for retrieving a contact
   * @throws Error if a data context is not provided
   */
  /**
   * Returns a contact for the given qualifier.
   * @param qualifier identifier for the contact to retrieve
   * @returns the contact or `null` if no contact is found for the qualifier
   * @throws Error if the qualifier is invalid
   */
	const get = (context: DataContext) => (qualifier: UuidQualifier) => Promise<Nullable<Contact>>

  /**
   * Returns a function for retrieving a contact from the given data context with the contact's parent lineage.
   * @param context the current data context
   * @returns a function for retrieving a contact with the contact's parent lineage
   * @throws Error if a data context is not provided
   */
  /**
   * Returns a contact for the given qualifier with the contact's parent lineage.
   * @param qualifier identifier for the contact to retrieve
   * @returns the contact or `null` if no contact is found for the qualifier
   * @throws Error if the qualifier is invalid
   */
	const getWithLineage = (context: DataContext) => (qualifier: UuidQualifier) => Promise<Nullable<ContactWithLineage>>

	// New REST api: /api/v1/contact/id
  /**
   * Returns a function for retrieving a paged array of contact identifiers from the given data context.
   * @param context the current data context
   * @returns a function for retrieving a paged array of contact identifiers
   * @throws Error if a data context is not provided
   * @see {@link getIdsAll} which provides the same data, but without having to manually account for paging
   */
  /**
   * Returns an array of contact identifiers for the provided page specifications.
   * @param qualifier the limiter defining which identifiers to return
   * @param cursor the token identifying which page to retrieve. A `null` value indicates the first page should be
   * returned. Subsequent pages can be retrieved by providing the cursor returned with the previous page.
   * @param limit the maximum number of identifiers to return. Default is 10000.
   * @returns a page of contact identifiers for the provided specification
   * @throws Error if no qualifier is provided or if the qualifier is invalid
   * @throws Error if the provided `limit` value is `<=0`
   * @throws Error if the provided cursor is not a valid page token or `null`
   */
    const getIdsPage = (context: DataContext) => (qualifier: ContactTypeQualifier | FreetextQualifier, cursor: Nullable<string>, limit: number) => Promise<Page<string>>

  /**
   * Returns a function for getting a generator that fetches contact identifiers from the given data context.
   * @param context the current data context
   * @returns a function for getting a generator that fetches contact identifiers
   * @throws Error if a data context is not provided
   */
  /**
   * Returns a generator for fetching all contact identifiers that match the given qualifier
   * @param qualifier the limiter defining which identifiers to return
   * @returns a generator for fetching all contact identifiers that match the given qualifier
   * @throws Error if no qualifier is provided or if the qualifier is invalid
   */
  const getIdsAll = (context: DataContext) => (qualifier: ContactTypeQualifier | FreetextQualifier) => AsyncGenerator<string, null>
}

namespace v1 {
  /**
   * A report document.
   */
  interface Report extends Doc {
    readonly form: string;
    readonly reported_date: Date;
    readonly fields: DataObject;
  }

  // New REST api: /api/v1/report
  /**
   * Returns a function for retrieving a report from the given data context.
   * @param context the current data context
   * @returns a function for retrieving a report
   * @throws Error if a data context is not provided
   */
  /**
   * Returns a report for the given qualifier.
   * @param qualifier identifier for the report to retrieve
   * @returns the report or `null` if no report is found for the qualifier
   * @throws Error if the qualifier is invalid
   */
	const get = (context: DataContext) => (qualifier: UuidQualifier) => Promise<Nullable<Report>>

	// New REST api: /api/v1/report/id
  /**
   * Returns a function for retrieving a paged array of report identifiers from the given data context.
   * @param context the current data context
   * @returns a function for retrieving a paged array of report identifiers
   * @throws Error if a data context is not provided
   * @see {@link getIdsAll} which provides the same data, but without having to manually account for paging
   */
  /**
   * Returns an array of report identifiers for the provided page specifications.
   * @param qualifier the limiter defining which identifiers to return
   * @param cursor the token identifying which page to retrieve. A `null` value indicates the first page should be
   * returned. Subsequent pages can be retrieved by providing the cursor returned with the previous page.
   * @param limit the maximum number of identifiers to return. Default is 10000.
   * @returns a page of report identifiers for the provided specification
   * @throws Error if no qualifier is provided or if the qualifier is invalid
   * @throws Error if the provided `limit` value is `<=0`
   * @throws Error if the provided cursor is not a valid page token or `null`
   */
    const getIdsPage = (context: DataContext) => (qualifier: FreetextQualifier, cursor: Nullable<string>, limit: number) => Promise<Page<string>>

  /**
   * Returns a function for getting a generator that fetches report identifiers from the given data context.
   * @param context the current data context
   * @returns a function for getting a generator that fetches report identifiers
   * @throws Error if a data context is not provided
   */
  /**
   * Returns a generator for fetching all report identifiers that match the given qualifier
   * @param qualifier the limiter defining which identifiers to return
   * @returns a generator for fetching all report identifiers that match the given qualifier
   * @throws Error if no qualifier is provided or if the qualifier is invalid
   */
  const getIdsAll = (context: DataContext) => (qualifier: FreetextQualifier) => AsyncGenerator<string, null>
}