const { BaseChatModel } = require("@langchain/core/language_models/chat_models");
const { JLINCTracer } = require("../tracer/index.js");
const { authDecide, authInvoke, getDescription, getName } = require("./common.js");

/**
 * @typedef {import('./common').JLINCConfig} JLINCConfig
 */

/**
 * @typedef {Object} JLINCAuthBaseChatModelFields
 * @property {JLINCConfig} config
 * @property {Tool} jlincAuthDecision
 * @property {BaseChatModel} targetAuthorized
 * @property {BaseChatModel|null} targetNotAuthorized
 */

class JLINCAuthBaseChatModel extends BaseChatModel {
  /**
   * @param {JLINCAuthBaseChatModelFields} fields
   */
  constructor({ config, jlincAuthDecision, targetAuthorized, targetNotAuthorized }) {
    super({
      name: "jlinc_auth_base_chat_model",
      description: "", // overridden dynamically
    });
    Object.defineProperty(this, "name", {
      enumerable: true,
      configurable: true,
      writable: true,
      value: getName(targetAuthorized, targetNotAuthorized)
    });
    Object.defineProperty(this, "description", {
      enumerable: true,
      configurable: true,
      writable: true,
      value: getDescription(targetAuthorized, targetNotAuthorized, 'BaseChatModel')
    });
    /** @type {JLINCConfig} */
    this.config = config;
    /** @type {Tool} */
    this.jlincAuthDecision = jlincAuthDecision;
    /** @type {BaseChatModel} */
    this.targetAuthorized = targetAuthorized;
    /** @type {BaseChatModel|null} */
    this.targetNotAuthorized = targetNotAuthorized;
    /** @type {JLINCTracer} */
    this.tracer = new JLINCTracer(config);
    /** @type {string} */
    this.authType = 'BaseChatModel';
  }

  /**
   * @param {BindToolsInput[]} tools - The tools to bind to the underlying models.
   * @param {Partial<CallOptions>} [kwargs] - Optional call options.
   * @returns {Runnable<BaseLanguageModelInput, OutputMessageType, CallOptions>}
   *   A new JLINCAuthBaseChatModel instance whose underlying models
   *   have been bound with the provided tools.
   */ 
  bindTools(tools, kwargs = {}) {
    if (this.config.debug)
      console.log(`[JLINCAuth] Binding tools to BaseChatModels`);
    const authorizedBound = this.targetAuthorized.bindTools(tools, kwargs);
    const notAuthorizedBound = this.targetNotAuthorized
      ? this.targetNotAuthorized.bindTools(tools, kwargs)
      : null;
    return new JLINCAuthBaseChatModel({
      config: this.config,
      jlincAuthDecision: this.jlincAuthDecision,
      targetAuthorized: authorizedBound,
      targetNotAuthorized: notAuthorizedBound,
    });
  }

  /**
   * @returns {string} - type
   */
  _llmType() {
    const type = this.targetAuthorized?._llmType?.() ?? "unknown";
    if (this.config?.debug)
      console.log(`[JLINCAuth] Returning LLM type: ${type}`);
    return type;
  } 

  /**
   * @param {BaseLanguageModelInput} input
   * @param {Partial<CallOptions>} [options] - Optional call options.
   * @returns {Promise<OutputMessageType>} A promise that resolves with the output.
   */
  async invoke(input, runManager) {
    return await authInvoke(this, input);
  }
}

module.exports = {
  JLINCAuthBaseChatModel,
};