/*
 * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
 * or more contributor license agreements. Licensed under the Elastic License
 * 2.0; you may not use this file except in compliance with the Elastic License
 * 2.0.
 */

import { OpenAiProviderType } from '@kbn/stack-connectors-plugin/public/common';

import { HttpSetup, IHttpFetchError } from '@kbn/core-http-browser';
import type { Conversation, Message } from '../assistant_context/types';
import { API_ERROR } from './translations';
import { MODEL_GPT_3_5_TURBO } from '../connectorland/models/model_selector/model_selector';
import {
  getFormattedMessageContent,
  getOptionalRequestParams,
  hasParsableResponse,
} from './helpers';
import { PerformEvaluationParams } from './settings/evaluation_settings/use_perform_evaluation';

export interface FetchConnectorExecuteAction {
  alerts: boolean;
  alertsIndexPattern?: string;
  allow?: string[];
  allowReplacement?: string[];
  assistantLangChain: boolean;
  assistantStreamingEnabled: boolean;
  apiConfig: Conversation['apiConfig'];
  http: HttpSetup;
  messages: Message[];
  onNewReplacements: (newReplacements: Record<string, string>) => void;
  ragOnAlerts: boolean;
  replacements?: Record<string, string>;
  signal?: AbortSignal | undefined;
  size?: number;
}

export interface FetchConnectorExecuteResponse {
  response: string | ReadableStreamDefaultReader<Uint8Array>;
  isError: boolean;
  isStream: boolean;
  traceData?: {
    transactionId: string;
    traceId: string;
  };
}

export const fetchConnectorExecuteAction = async ({
  alerts,
  alertsIndexPattern,
  allow,
  allowReplacement,
  assistantLangChain,
  assistantStreamingEnabled,
  http,
  messages,
  onNewReplacements,
  ragOnAlerts,
  replacements,
  apiConfig,
  signal,
  size,
}: FetchConnectorExecuteAction): Promise<FetchConnectorExecuteResponse> => {
  const outboundMessages = messages.map((msg) => ({
    role: msg.role,
    content: msg.content,
  }));

  const body =
    apiConfig?.provider === OpenAiProviderType.OpenAi
      ? {
          model: apiConfig.model ?? MODEL_GPT_3_5_TURBO,
          messages: outboundMessages,
          n: 1,
          stop: null,
          temperature: 0.2,
        }
      : {
          // Azure OpenAI and Bedrock invokeAI both expect this body format
          messages: outboundMessages,
        };

  // TODO: Remove in part 3 of streaming work for security solution
  // tracked here: https://github.com/elastic/security-team/issues/7363
  // In part 3 I will make enhancements to langchain to introduce streaming
  // Once implemented, invokeAI can be removed
  const isStream = assistantStreamingEnabled && !assistantLangChain;
  const optionalRequestParams = getOptionalRequestParams({
    alerts,
    alertsIndexPattern,
    allow,
    allowReplacement,
    ragOnAlerts,
    replacements,
    size,
  });

  const requestBody = isStream
    ? {
        params: {
          subActionParams: body,
          subAction: 'invokeStream',
        },
        assistantLangChain,
        ...optionalRequestParams,
      }
    : {
        params: {
          subActionParams: body,
          subAction: 'invokeAI',
        },
        assistantLangChain,
        ...optionalRequestParams,
      };

  try {
    if (isStream) {
      const response = await http.fetch(
        `/internal/elastic_assistant/actions/connector/${apiConfig?.connectorId}/_execute`,
        {
          method: 'POST',
          body: JSON.stringify(requestBody),
          signal,
          asResponse: isStream,
          rawResponse: isStream,
        }
      );

      const reader = response?.response?.body?.getReader();

      if (!reader) {
        return {
          response: `${API_ERROR}\n\nCould not get reader from response`,
          isError: true,
          isStream: false,
        };
      }
      return {
        response: reader,
        isStream: true,
        isError: false,
      };
    }

    // TODO: Remove in part 3 of streaming work for security solution
    // tracked here: https://github.com/elastic/security-team/issues/7363
    // This is a temporary code to support the non-streaming API
    const response = await http.fetch<{
      connector_id: string;
      status: string;
      data: string;
      replacements?: Record<string, string>;
      service_message?: string;
      trace_data?: {
        transaction_id: string;
        trace_id: string;
      };
    }>(`/internal/elastic_assistant/actions/connector/${apiConfig?.connectorId}/_execute`, {
      method: 'POST',
      body: JSON.stringify(requestBody),
      headers: { 'Content-Type': 'application/json' },
      signal,
    });

    if (response.status !== 'ok' || !response.data) {
      if (response.service_message) {
        return {
          response: `${API_ERROR}\n\n${response.service_message}`,
          isError: true,
          isStream: false,
        };
      }
      return {
        response: API_ERROR,
        isError: true,
        isStream: false,
      };
    }

    // Only add traceData if it exists in the response
    const traceData =
      response.trace_data?.trace_id != null && response.trace_data?.transaction_id != null
        ? {
            traceId: response.trace_data?.trace_id,
            transactionId: response.trace_data?.transaction_id,
          }
        : undefined;

    onNewReplacements(response.replacements ?? {});

    return {
      response: hasParsableResponse({
        alerts,
        assistantLangChain,
        ragOnAlerts,
      })
        ? getFormattedMessageContent(response.data)
        : response.data,
      isError: false,
      isStream: false,
      traceData,
    };
  } catch (error) {
    const getReader = error?.response?.body?.getReader;
    const reader =
      isStream && typeof getReader === 'function' ? getReader.call(error.response.body) : null;

    if (!reader) {
      return {
        response: `${API_ERROR}\n\n${error?.body?.message ?? error?.message}`,
        isError: true,
        isStream: false,
      };
    }
    return {
      response: reader,
      isStream: true,
      isError: true,
    };
  }
};

export interface GetKnowledgeBaseStatusParams {
  http: HttpSetup;
  resource?: string;
  signal?: AbortSignal | undefined;
}

export interface GetKnowledgeBaseStatusResponse {
  elser_exists: boolean;
  esql_exists?: boolean;
  index_exists: boolean;
  pipeline_exists: boolean;
}

/**
 * API call for getting the status of the Knowledge Base. Provide
 * a resource to include the status of that specific resource.
 *
 * @param {Object} options - The options object.
 * @param {HttpSetup} options.http - HttpSetup
 * @param {string} [options.resource] - Resource to get the status of, otherwise status of overall KB
 * @param {AbortSignal} [options.signal] - AbortSignal
 *
 * @returns {Promise<GetKnowledgeBaseStatusResponse | IHttpFetchError>}
 */
export const getKnowledgeBaseStatus = async ({
  http,
  resource,
  signal,
}: GetKnowledgeBaseStatusParams): Promise<GetKnowledgeBaseStatusResponse | IHttpFetchError> => {
  try {
    const path = `/internal/elastic_assistant/knowledge_base/${resource || ''}`;
    const response = await http.fetch(path, {
      method: 'GET',
      signal,
    });

    return response as GetKnowledgeBaseStatusResponse;
  } catch (error) {
    return error as IHttpFetchError;
  }
};

export interface PostKnowledgeBaseParams {
  http: HttpSetup;
  resource?: string;
  signal?: AbortSignal | undefined;
}

export interface PostKnowledgeBaseResponse {
  success: boolean;
}

/**
 * API call for setting up the Knowledge Base. Provide a resource to set up a specific resource.
 *
 * @param {Object} options - The options object.
 * @param {HttpSetup} options.http - HttpSetup
 * @param {string} [options.resource] - Resource to be added to the KB, otherwise sets up the base KB
 * @param {AbortSignal} [options.signal] - AbortSignal
 *
 * @returns {Promise<PostKnowledgeBaseResponse | IHttpFetchError>}
 */
export const postKnowledgeBase = async ({
  http,
  resource,
  signal,
}: PostKnowledgeBaseParams): Promise<PostKnowledgeBaseResponse | IHttpFetchError> => {
  try {
    const path = `/internal/elastic_assistant/knowledge_base/${resource || ''}`;
    const response = await http.fetch(path, {
      method: 'POST',
      signal,
    });

    return response as PostKnowledgeBaseResponse;
  } catch (error) {
    return error as IHttpFetchError;
  }
};

export interface DeleteKnowledgeBaseParams {
  http: HttpSetup;
  resource?: string;
  signal?: AbortSignal | undefined;
}

export interface DeleteKnowledgeBaseResponse {
  success: boolean;
}

/**
 * API call for deleting the Knowledge Base. Provide a resource to delete that specific resource.
 *
 * @param {Object} options - The options object.
 * @param {HttpSetup} options.http - HttpSetup
 * @param {string} [options.resource] - Resource to be deleted from the KB, otherwise delete the entire KB
 * @param {AbortSignal} [options.signal] - AbortSignal
 *
 * @returns {Promise<DeleteKnowledgeBaseResponse | IHttpFetchError>}
 */
export const deleteKnowledgeBase = async ({
  http,
  resource,
  signal,
}: DeleteKnowledgeBaseParams): Promise<DeleteKnowledgeBaseResponse | IHttpFetchError> => {
  try {
    const path = `/internal/elastic_assistant/knowledge_base/${resource || ''}`;
    const response = await http.fetch(path, {
      method: 'DELETE',
      signal,
    });

    return response as DeleteKnowledgeBaseResponse;
  } catch (error) {
    return error as IHttpFetchError;
  }
};

export interface PostEvaluationParams {
  http: HttpSetup;
  evalParams?: PerformEvaluationParams;
  signal?: AbortSignal | undefined;
}

export interface PostEvaluationResponse {
  evaluationId: string;
  success: boolean;
}

/**
 * API call for evaluating models.
 *
 * @param {Object} options - The options object.
 * @param {HttpSetup} options.http - HttpSetup
 * @param {string} [options.evalParams] - Params necessary for evaluation
 * @param {AbortSignal} [options.signal] - AbortSignal
 *
 * @returns {Promise<PostEvaluationResponse | IHttpFetchError>}
 */
export const postEvaluation = async ({
  http,
  evalParams,
  signal,
}: PostEvaluationParams): Promise<PostEvaluationResponse | IHttpFetchError> => {
  try {
    const path = `/internal/elastic_assistant/evaluate`;
    const query = {
      agents: evalParams?.agents.sort()?.join(','),
      datasetName: evalParams?.datasetName,
      evaluationType: evalParams?.evaluationType.sort()?.join(','),
      evalModel: evalParams?.evalModel.sort()?.join(','),
      outputIndex: evalParams?.outputIndex,
      models: evalParams?.models.sort()?.join(','),
      projectName: evalParams?.projectName,
      runName: evalParams?.runName,
    };

    const response = await http.fetch(path, {
      method: 'POST',
      body: JSON.stringify({
        dataset: JSON.parse(evalParams?.dataset ?? '[]'),
        evalPrompt: evalParams?.evalPrompt ?? '',
      }),
      headers: {
        'Content-Type': 'application/json',
      },
      query,
      signal,
    });

    return response as PostEvaluationResponse;
  } catch (error) {
    return error as IHttpFetchError;
  }
};