/**
 * Copyright (c) Microsoft Corporation. All rights reserved.
 * Licensed under the MIT License.
 */
import { Activity, ExceptionHelper } from '@microsoft/agents-activity'
import { Errors } from './errorHelper'
import { Configurable } from './configurable'
import { DialogContext } from './dialogContext'
import omit from 'lodash/omit'
import { RecognizerResult, getTopScoringIntent } from './recognizerResult'

/**
 * Configuration options for a recognizer instance.
 *
 * @remarks
 * This interface defines the configuration properties that can be used to customize
 * the behavior and identification of a recognizer. Recognizers use this configuration
 * to set up their basic properties and operational parameters.
 *
 */
export interface RecognizerConfiguration {
  /**
   * Optional unique identifier for the recognizer instance.
   *
   * @remarks
   * The id property allows you to distinguish between multiple recognizer instances
   * and can be useful for logging, debugging, and telemetry purposes. If not provided,
   * the recognizer will operate without a specific identifier.
   *
   */
  id?: string;
}

/**
 * Base class for implementing custom recognizers to identify intents and entities from user input.
 *
 * @remarks
 * Recognizers process user input, such as text or speech, and return structured data representing
 * the recognized intents, entities, and other relevant information. This class provides a foundation
 * for creating custom recognizers by defining common methods and properties.
 *
 */
export class Recognizer extends Configurable implements RecognizerConfiguration {
  /**
   * Optional. The unique identifier for the recognizer.
   */
  id?: string
  /**
     * To recognize intents and entities in a users utterance.
     *
     * @param {DialogContext} _dialogContext Dialog Context.
     * @param {Partial<Activity>} _activity Activity.
     * @param {Record<string, string>} _telemetryProperties Additional properties to be logged to telemetry with event.
     * @param {Record<string, number>} _telemetryMetrics Additional metrics to be logged to telemetry with event.
     */
  recognize (
    _dialogContext: DialogContext,
    _activity: Partial<Activity>,
    _telemetryProperties?: Record<string, string>,
    _telemetryMetrics?: Record<string, number>
  ): Promise<RecognizerResult> {
    throw ExceptionHelper.generateException(
      Error,
      Errors.RecognizeFunctionNotImplemented
    )
  }

  /**
     * Creates choose intent result in the case that there are conflicting or ambiguous signals from the recognizers.
     *
     * @param {Record<string, RecognizerResult>} recognizerResults A group of recognizer results.
     * @returns {RecognizerResult} Recognizer result which is ChooseIntent.
     */
  protected createChooseIntentResult (recognizerResults: Record<string, RecognizerResult>): RecognizerResult {
    let text: string = ''
    let sentiment: Record<string, any> = {}
        type candidateType = { id: string; intent: string; score: number; result: RecognizerResult }
        const candidates = Object.entries(recognizerResults).reduce((candidates: candidateType[], [key, result]) => {
          text = result.text
          sentiment = result.sentiment
          const { intent, score } = getTopScoringIntent(result)
          if (intent !== 'None') {
            candidates.push({
              id: key,
              intent,
              score,
              result,
            })
          }
          return candidates
        }, [])

        if (candidates.length) {
          const recognizerResult: RecognizerResult = {
            text,
            intents: { ChooseIntent: { score: 1.0 } },
            candidates,
            entities: {},
          }
          return recognizerResult
        }

        // just return a `None` intent.
        const recognizerResult: RecognizerResult = {
          text,
          intents: { None: { score: 1.0 } },
          entities: {},
          sentiment,
        }
        return recognizerResult
  }

  /**
     * Uses the RecognizerResult to create a list of properties to be included when tracking the result in telemetry.
     *
     * @param {RecognizerResult} recognizerResult Recognizer Result.
     * @param {Record<string, string>} telemetryProperties A list of properties to append or override the properties created using the RecognizerResult.
     * @param {DialogContext} _dialogContext Dialog Context.
     * @returns {Record<string, string>} A collection of properties that can be included when calling the TrackEvent method on the TelemetryClient.
     */
  protected fillRecognizerResultTelemetryProperties (
    recognizerResult: RecognizerResult,
    telemetryProperties: Record<string, string>,
    _dialogContext?: DialogContext
  ): Record<string, string> {
    const { intent, score } = getTopScoringIntent(recognizerResult)
    const intents = Object.entries(recognizerResult.intents)

    const properties: Record<string, string > = {
      Text: recognizerResult.text,
      AlteredText: recognizerResult.alteredText ?? '',
      TopIntent: intents.length > 0 ? intent : '',
      TopIntentScore: intents.length > 0 ? score.toString() : '',
      Intents: intents.length > 0 ? JSON.stringify(recognizerResult.intents) : '',
      Entities: recognizerResult.entities ? JSON.stringify(recognizerResult.entities) : '',
      AdditionalProperties: JSON.stringify(
        omit(recognizerResult, ['text', 'alteredText', 'intents', 'entities'])
      ),
    }

    if (telemetryProperties) {
      return Object.assign({}, properties, telemetryProperties)
    }

    return properties
  }

  protected stringifyAdditionalPropertiesOfRecognizerResult (recognizerResult: RecognizerResult): string {
    const generalProperties = new Set(['text', 'alteredText', 'intents', 'entities'])
    const additionalProperties: { [key: string]: string } = {}
    for (const key in recognizerResult) {
      if (!generalProperties.has(key)) {
        additionalProperties[key] = recognizerResult[key]
      }
    }
    return Object.keys(additionalProperties).length > 0 ? JSON.stringify(additionalProperties) : ''
  }
}