import { HttpMigration } from "./HttpMigration";
import { OpenApi } from "./OpenApi";
import { OpenApiV3 } from "./OpenApiV3";
import { OpenApiV3_1 } from "./OpenApiV3_1";
import { SwaggerV2 } from "./SwaggerV2";
import { HttpLlmComposer } from "./composers/HttpLlmApplicationComposer";
import { HttpLlmFunctionFetcher } from "./http/HttpLlmFunctionFetcher";
import { IHttpConnection } from "./structures/IHttpConnection";
import { IHttpLlmApplication } from "./structures/IHttpLlmApplication";
import { IHttpLlmFunction } from "./structures/IHttpLlmFunction";
import { IHttpMigrateApplication } from "./structures/IHttpMigrateApplication";
import { IHttpResponse } from "./structures/IHttpResponse";
import { ILlmFunction } from "./structures/ILlmFunction";
import { LlmDataMerger } from "./utils/LlmDataMerger";

/**
 * LLM function calling application composer from OpenAPI document.
 *
 * `HttpLlm` is a module for composing LLM (Large Language Model) function
 * calling application from the {@link OpenApi.IDocument OpenAPI document}, and
 * also for LLM function call execution and parameter merging.
 *
 * At first, you can construct the LLM function calling application by the
 * {@link HttpLlm.application HttpLlm.application()} function. And then the LLM
 * has selected a {@link IHttpLlmFunction function} to call and composes its
 * arguments, you can execute the function by
 * {@link HttpLlm.execute HttpLlm.execute()} or
 * {@link HttpLlm.propagate HttpLlm.propagate()}.
 *
 * By the way, if you have configured the
 * {@link IHttpLlmApplication.IConfig.separate} option to separate the parameters
 * into human and LLM sides, you can merge these human and LLM sides' parameters
 * into one through {@link HttpLlm.mergeParameters HttpLlm.mergeParameters()}
 * before the actual LLM function call execution.
 *
 * @author Jeongho Nam - https://github.com/samchon
 */
export namespace HttpLlm {
  /* -----------------------------------------------------------
    COMPOSERS
  ----------------------------------------------------------- */
  /** Properties for the LLM function calling application composer. */
  export interface IApplicationProps {
    /** OpenAPI document to convert. */
    document:
      | OpenApi.IDocument
      | SwaggerV2.IDocument
      | OpenApiV3.IDocument
      | OpenApiV3_1.IDocument;

    /** Configuration for the LLM function calling schema conversion. */
    config?: Partial<IHttpLlmApplication.IConfig>;
  }

  /**
   * Convert OpenAPI document to LLM function calling application.
   *
   * Converts {@link OpenApi.IDocument OpenAPI document} or
   * {@link IHttpMigrateApplication migrated application} to the
   * {@link IHttpLlmApplication LLM function calling application}. Every
   * {@link OpenApi.IOperation API operations} in the OpenAPI document are
   * converted to the {@link IHttpLlmFunction LLM function} type, and they would
   * be used for the LLM function calling.
   *
   * If you have configured the {@link IHttpLlmApplication.IConfig.separate}
   * option, every parameters in the {@link IHttpLlmFunction} would be separated
   * into both human and LLM sides. In that case, you can merge these human and
   * LLM sides' parameters into one through {@link HttpLlm.mergeParameters}
   * before the actual LLM function call execution.
   *
   * @param props Properties for composition
   * @returns LLM function calling application
   */
  export const application = (
    props: IApplicationProps,
  ): IHttpLlmApplication => {
    // MIGRATE
    const migrate: IHttpMigrateApplication = HttpMigration.application(
      props.document,
    );
    return HttpLlmComposer.application({
      migrate,
      config: {
        reference: props.config?.reference ?? true,
        strict: props.config?.strict ?? false,
        separate: props.config?.separate ?? null,
        maxLength: props.config?.maxLength ?? 64,
        equals: props.config?.equals ?? false,
      },
    });
  };

  /* -----------------------------------------------------------
    FETCHERS
  ----------------------------------------------------------- */
  /** Properties for the LLM function call. */
  export interface IFetchProps {
    /** Application of the LLM function calling. */
    application: IHttpLlmApplication;

    /** LLM function schema to call. */
    function: IHttpLlmFunction;

    /** Connection info to the HTTP server. */
    connection: IHttpConnection;

    /** Input arguments for the function call. */
    input: object;
  }

  /**
   * Execute the LLM function call.
   *
   * `HttmLlm.execute()` is a function executing the target
   * {@link OpenApi.IOperation API endpoint} with with the connection information
   * and arguments composed by Large Language Model like OpenAI (+human
   * sometimes).
   *
   * By the way, if you've configured the
   * {@link IHttpLlmApplication.IConfig.separate}, so that the parameters are
   * separated to human and LLM sides, you have to merge these human and LLM
   * sides' parameters into one through {@link HttpLlm.mergeParameters}
   * function.
   *
   * For reference, if the target API endpoint responds none 200/201 status,
   * this would be considered as an error and the {@link HttpError} would be
   * thrown. Otherwise you don't want such rule, you can use the
   * {@link HttpLlm.propagate} function instead.
   *
   * @param props Properties for the LLM function call
   * @returns Return value (response body) from the API endpoint
   * @throws HttpError when the API endpoint responds none 200/201 status
   */
  export const execute = (props: IFetchProps): Promise<unknown> =>
    HttpLlmFunctionFetcher.execute(props);

  /**
   * Propagate the LLM function call.
   *
   * `HttmLlm.propagate()` is a function propagating the target
   * {@link OpenApi.IOperation API endpoint} with with the connection information
   * and arguments composed by Large Language Model like OpenAI (+human
   * sometimes).
   *
   * By the way, if you've configured the
   * {@link IHttpLlmApplication.IConfig.separate}, so that the parameters are
   * separated to human and LLM sides, you have to merge these humand and LLM
   * sides' parameters into one through {@link HttpLlm.mergeParameters}
   * function.
   *
   * For reference, the propagation means always returning the response from the
   * API endpoint, even if the status is not 200/201. This is useful when you
   * want to handle the response by yourself.
   *
   * @param props Properties for the LLM function call
   * @returns Response from the API endpoint
   * @throws Error only when the connection is failed
   */
  export const propagate = (props: IFetchProps): Promise<IHttpResponse> =>
    HttpLlmFunctionFetcher.propagate(props);

  /* -----------------------------------------------------------
    MERGERS
  ----------------------------------------------------------- */
  /** Properties for the parameters' merging. */
  export interface IMergeProps {
    /** Metadata of the target function. */
    function: ILlmFunction;

    /** Arguments composed by the LLM. */
    llm: object | null;

    /** Arguments composed by the human. */
    human: object | null;
  }

  /**
   * Merge the parameters.
   *
   * If you've configured the {@link IHttpLlmApplication.IConfig.separate}
   * option, so that the parameters are separated to human and LLM sides, you
   * can merge these humand and LLM sides' parameters into one through this
   * `HttpLlm.mergeParameters()` function before the actual LLM function call
   * execution.
   *
   * On contrary, if you've not configured the
   * {@link IHttpLlmApplication.IConfig.separate} option, this function would
   * throw an error.
   *
   * @param props Properties for the parameters' merging
   * @returns Merged parameter values
   */
  export const mergeParameters = (props: IMergeProps): object =>
    LlmDataMerger.parameters(props);

  /**
   * Merge two values.
   *
   * If both values are objects, then combines them in the properties level.
   *
   * Otherwise, returns the latter value if it's not null, otherwise the former
   * value.
   *
   * - `return (y ?? x)`
   *
   * @param x Value X to merge
   * @param y Value Y to merge
   * @returns Merged value
   */
  export const mergeValue = (x: unknown, y: unknown): unknown =>
    LlmDataMerger.value(x, y);
}