chrome-devtools-frontend/front_end/core/host/AidaGcaTranslation.ts

Chrome DevTools UI

// Copyright 2026 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import * as AIDA from './AidaClientTypes.js';
import * as GCA from './GcaTypes.js';

type AidaRequest = AIDA.DoConversationRequest|AIDA.CompletionRequest|AIDA.GenerateCodeRequest;

function createBaseGcaRequest(
    request: AidaRequest, contents: GCA.Content[], experience: string): GCA.GenerateContentRequest {
  const gcaRequest: GCA.GenerateContentRequest = {contents, aicode: {experience}};
  mapCommonAidaRequestFields(request, gcaRequest);
  buildLabels(request, gcaRequest);

  if ('preamble' in request && request.preamble) {
    gcaRequest.systemInstruction = {
      role: 'user',
      parts: [{text: request.preamble}],
    };
  }

  return gcaRequest;
}

export function aidaDoConversationRequestToGcaRequest(request: AIDA.DoConversationRequest): GCA.GenerateContentRequest {
  try {
    const contents: GCA.Content[] = [];

    if (request.facts) {
      contents.push(convertAidaFactsToGcaContent(request.facts));
    }

    if (request.historical_contexts) {
      contents.push(...(request.historical_contexts).map(convertAidaContentToGcaContent));
    }
    contents.push(convertAidaContentToGcaContent(request.current_message));

    const gcaRequest = createBaseGcaRequest(request, contents, 'chat_console_insights');

    if (request.function_declarations) {
      gcaRequest.tools = [{
        functionDeclarations:
            (request.function_declarations).map(fd => ({
                                                  name: fd.name,
                                                  description: fd.description,
                                                  parameters: convertAidaParamToGcaSchema(fd.parameters),
                                                })),
      }];
    }
    AIDA.debugLog('Translation succeded:', JSON.stringify(request), JSON.stringify(gcaRequest));
    return gcaRequest;
  } catch (e) {
    AIDA.debugLog('Translation error:', JSON.stringify(request), e);
    throw e;
  }
}

function mapCommonAidaRequestFields(aidaRequest: AidaRequest, gcaRequest: GCA.GenerateContentRequest): void {
  if (aidaRequest.options?.model_id) {
    gcaRequest.model = aidaRequest.options.model_id;
  }
  if (aidaRequest.options?.temperature !== undefined) {
    gcaRequest.generationConfig = {
      ...gcaRequest.generationConfig,
      temperature: aidaRequest.options.temperature,
    };
  }
}

export function gcaResponseToAidaDoConversationResponse(response: GCA.GenerateContentResponse):
    AIDA.DoConversationResponse {
  const functionCalls: AIDA.AidaFunctionCallResponse[] = [];

  if (response.candidates?.[0].content?.parts) {
    for (const part of response.candidates[0].content.parts) {
      if (part.functionCall) {
        functionCalls.push({
          name: part.functionCall.name,
          args: part.functionCall.args || {},
        });
      }
    }
  }

  return {
    explanation: extractTextFromGcaParts(response.candidates[0].content?.parts),
    metadata: {
      rpcGlobalId: response.responseId,
    },
    functionCalls: functionCalls.length > 0 ?
        (functionCalls as [AIDA.AidaFunctionCallResponse, ...AIDA.AidaFunctionCallResponse[]]) :
        undefined,
    completed: true,
  };
}

function extractTextFromGcaParts(parts: GCA.Part[]|undefined): string {
  if (!parts) {
    return '';
  }
  return parts.map(p => p.text || '').join('');
}

export function aidaEventToGcaTelemetryRequest(clientEvent: AIDA.AidaRegisterClientEvent): GCA.SendTelemetryRequest {
  try {
    const feedbackMetrics: GCA.FeedbackMetric[] = [];
    const responseId = String(clientEvent.corresponding_aida_rpc_global_id);
    const eventTime = new Date().toISOString();

    if (clientEvent.do_conversation_client_event) {
      const feedback = clientEvent.do_conversation_client_event.user_feedback;
      if (feedback.sentiment) {
        let interaction: GCA.InteractionType = GCA.InteractionType.INTERACTION_TYPE_UNSPECIFIED;
        if (feedback.sentiment === AIDA.Rating.POSITIVE) {
          interaction = GCA.InteractionType.THUMBS_UP;
        } else if (feedback.sentiment === AIDA.Rating.NEGATIVE) {
          interaction = GCA.InteractionType.THUMBS_DOWN;
        }
        feedbackMetrics.push({
          eventTime,
          responseId,
          suggestionInteraction: {interaction},
        });
      }
    }

    feedbackMetrics.push(...convertCodeTelemetry(
        clientEvent.complete_code_client_event, GCA.Method.COMPLETE_CODE, responseId, eventTime));
    feedbackMetrics.push(...convertCodeTelemetry(
        clientEvent.generate_code_client_event, GCA.Method.GENERATE_CODE, responseId, eventTime));
    const gcaTelemetryRequest: GCA.SendTelemetryRequest = {
      feedbackMetrics,
    };
    AIDA.debugLog('Translation succeeded:', JSON.stringify(clientEvent), JSON.stringify(gcaTelemetryRequest));
    return gcaTelemetryRequest;
  } catch (e) {
    AIDA.debugLog('Translation error:', JSON.stringify(clientEvent), e);
    throw e;
  }
}

/* eslint-disable @typescript-eslint/naming-convention */
function convertCodeTelemetry(
    event: {user_acceptance?: AIDA.UserAcceptance, user_impression?: AIDA.UserImpression}|undefined, method: GCA.Method,
    responseId: string, eventTime: string): GCA.FeedbackMetric[] {
  if (!event) {
    return [];
  }
  if ('user_impression' in event && event.user_impression) {
    const impression = event.user_impression;
    return [{
      eventTime,
      responseId,
      suggestionOffered: {
        method,
        status: GCA.SuggestionStatus.NO_ERROR,
        responseLatency: `${impression.latency.duration.seconds + impression.latency.duration.nanos / 1e9}s`,
      },
    }];
  }
  if ('user_acceptance' in event && event.user_acceptance) {
    const acceptance = event.user_acceptance;
    return [{
      eventTime,
      responseId,
      suggestionInteraction: {
        interaction: GCA.InteractionType.ACCEPT,
        candidateIndex: acceptance.sample.sample_id,
      },
    }];
  }
  return [];
}
/* eslint-enable @typescript-eslint/naming-convention */

export function aidaCompletionRequestToGcaRequest(request: AIDA.CompletionRequest): GCA.GenerateContentRequest {
  try {
    let additionalFiles: GCA.SourceFile[] =
        (request.additional_files ?? []).map(f => ({
                                               fileUri: f.path,
                                               inclusionReason: [AidaReasonToGcaInclusionReason[f.included_reason]],
                                               segments: [{content: f.content, isSelected: false}],
                                             }));

    const inEditorFile: GCA.SourceFile = inFileEditRequestToSourceFile(request);
    if (inEditorFile) {
      additionalFiles = [inEditorFile, ...additionalFiles];
    }

    const gcaRequest = createBaseGcaRequest(request, [], 'complete_code');
    gcaRequest.aicode.files = additionalFiles;
    if (request.options?.stop_sequences) {
      gcaRequest.generationConfig = {
        ...gcaRequest.generationConfig,
        stopSequences: request.options.stop_sequences,
      };
    }
    AIDA.debugLog('Translation succeeded:', JSON.stringify(request), JSON.stringify(gcaRequest));
    return gcaRequest;
  } catch (e) {
    AIDA.debugLog('Translation error:', JSON.stringify(request), e);
    throw e;
  }
}

function inFileEditRequestToSourceFile(request: AIDA.CompletionRequest): GCA.SourceFile {
  const sourceFile: GCA.SourceFile = {
    inclusionReason: [GCA.InclusionReason.ACTIVE],
    fileUri: 'devtools-code-completion',
    segments: [
      {
        content: request.prefix,
        isSelected: false,
      },
      {
        content: '',
        isSelected: true,  // Cursor position
      }
    ],
  };
  if (request.suffix) {
    sourceFile.segments?.push({
      content: request.suffix,
      isSelected: false,
    });
  }
  return sourceFile;
}

/* eslint-disable @typescript-eslint/naming-convention */
function buildLabels(request: AidaRequest, gcaRequest: GCA.GenerateContentRequest): void {
  const labels: Record<string, string> = {};
  if (request.client) {
    labels['client'] = request.client;
  }
  if ('functionality_type' in request && request.functionality_type !== undefined) {
    labels['functionality_type'] = AIDA.FunctionalityType[request.functionality_type];
  }
  if ('client_feature' in request && request.client_feature !== undefined) {
    labels['client_feature'] = AIDA.ClientFeature[request.client_feature];
  }
  if ('last_user_action' in request && request.last_user_action !== undefined) {
    labels['last_user_action'] = AIDA.EditType[request.last_user_action];
  }
  if ('use_case' in request && request.use_case !== undefined) {
    labels['use_case'] = AIDA.UseCase[request.use_case];
  }
  if (request.metadata.string_session_id) {
    labels['session_id'] = request.metadata.string_session_id;
  }
  const options = request.options as {
    inference_language?: string,
    expect_code_output?: boolean,
  } | undefined;
  if (options?.inference_language) {
    labels['inference_language'] = options.inference_language;
  }
  if (options?.expect_code_output !== undefined) {
    labels['expect_code_output'] = String(options.expect_code_output);
  }
  if (request.metadata.disable_user_content_logging !== undefined) {
    labels['disable_user_content_logging'] = String(request.metadata.disable_user_content_logging);
  }
  if (request.metadata.client_version) {
    labels['client_version'] = request.metadata.client_version;
  }

  if (Object.keys(labels).length > 0) {
    gcaRequest.labels = labels;
  }
}
/* eslint-enable @typescript-eslint/naming-convention */

const AidaReasonToGcaInclusionReason: Record<AIDA.Reason, GCA.InclusionReason> = {
  [AIDA.Reason.UNKNOWN]: GCA.InclusionReason.INCLUSION_REASON_UNSPECIFIED,
  [AIDA.Reason.CURRENTLY_OPEN]: GCA.InclusionReason.OPEN,
  // Intentional mapping due to type mismatch
  // TODO(liviurau): find a way to validate this mapping
  [AIDA.Reason.RECENTLY_OPENED]: GCA.InclusionReason.RECENTLY_CLOSED,
  [AIDA.Reason.RECENTLY_EDITED]: GCA.InclusionReason.RECENTLY_EDITED,
  [AIDA.Reason.COLOCATED]: GCA.InclusionReason.COLOCATED,
  [AIDA.Reason.RELATED_FILE]: GCA.InclusionReason.RELATED,
};

export function gcaResponseToAidaCompletionResponse(response: GCA.GenerateContentResponse): AIDA.CompletionResponse {
  try {
    const {samples, metadata} = gcaResponseToAidaSamplesAndMetadata(response);
    const aidaResponse: AIDA.CompletionResponse = {
      generatedSamples: samples,
      metadata,
    };
    AIDA.debugLog('Translation succeeded:', JSON.stringify(response), JSON.stringify(aidaResponse));
    return aidaResponse;
  } catch (e) {
    AIDA.debugLog('Translation error', JSON.stringify(response), e);
    throw e;
  }
}

function gcaResponseToAidaSamplesAndMetadata(response: GCA.GenerateContentResponse): {
  samples: AIDA.GenerationSample[],
  metadata: AIDA.ResponseMetadata,
} {
  return {
    samples: (response.candidates ?? []).map(gcaCandidateToAidaGenerationSample),
    metadata: {
      rpcGlobalId: response.responseId,
    },
  };
}

export function aidaGenerateCodeRequestToGcaRequest(request: AIDA.GenerateCodeRequest): GCA.GenerateContentRequest {
  try {
    const gcaRequest =
        createBaseGcaRequest(request, [convertAidaContentToGcaContent(request.current_message)], 'generate_code');
    if (request.context_files) {
      gcaRequest.aicode.files = (request.context_files).map(f => ({
                                                              fileUri: f.path,
                                                              programmingLanguage: f.programming_language,
                                                            }));
    }
    AIDA.debugLog('Translation succeeded:', JSON.stringify(request), JSON.stringify(gcaRequest));
    return gcaRequest;
  } catch (e) {
    AIDA.debugLog('Translation error', JSON.stringify(request), e);
    throw e;
  }
}

export function gcaResponseToAidaGenerateCodeResponse(response: GCA.GenerateContentResponse):
    AIDA.GenerateCodeResponse {
  try {
    const aidaResponse: AIDA.GenerateCodeResponse = gcaResponseToAidaSamplesAndMetadata(response);
    AIDA.debugLog('Translation succeeded:', JSON.stringify(response), JSON.stringify(aidaResponse));
    return aidaResponse;
  } catch (e) {
    AIDA.debugLog('translation error', JSON.stringify(response), e);
    throw e;
  }
}

function gcaCandidateToAidaGenerationSample(candidate: GCA.Candidate): AIDA.GenerationSample {
  const generationSample: AIDA.GenerationSample = {
    generationString: extractTextFromGcaParts(candidate.content?.parts),
    score: 0,
    sampleId: candidate.index,
  };
  if (candidate.citationMetadata) {
    generationSample.attributionMetadata = {
      attributionAction: AIDA.RecitationAction.CITE,
      citations: (candidate.citationMetadata.citations ?? []).map(c => ({
                                                                    startIndex: c.startIndex,
                                                                    endIndex: c.endIndex,
                                                                    uri: c.uri,
                                                                  })),
    };
  }
  return generationSample;
}

function convertAidaFactsToGcaContent(facts: AIDA.RequestFact[]): GCA.Content {
  return {
    role: 'user',
    parts: facts.map(fact => {
      return {text: `[source: ${fact.metadata.source}] ${fact.text}`};
    }),
  };
}

function convertAidaContentToGcaContent(content: AIDA.Content): GCA.Content {
  // TODO(liviurau): decide how to map AIDA.Role.SYSTEM
  // currently it will default to 'user'
  let role: GCA.Role = 'user';

  if (content.role === AIDA.Role.MODEL) {
    role = 'model';
  }
  return {
    role,
    parts: (content.parts ?? []).map(convertAidaPartToGcaPart),
  };
}

function convertAidaPartToGcaPart(part: AIDA.Part): GCA.Part {
  if ('text' in part) {
    return {text: part.text};
  }
  if ('functionCall' in part) {
    return {
      functionCall: {
        name: part.functionCall.name,
        args: part.functionCall.args,
      },
    };
  }
  if ('functionResponse' in part) {
    const fResponse: Record<string, unknown> = {};
    if ('result' in part.functionResponse.response) {
      fResponse.output = part.functionResponse.response['result'];
    } else if ('output' in part.functionResponse.response) {
      fResponse.output = part.functionResponse.response['output'];
    } else if (!('error' in part.functionResponse.response)) {
      fResponse.output = part.functionResponse.response;
    }
    if ('error' in part.functionResponse.response) {
      fResponse.error = part.functionResponse.response['error'];
    }
    return {
      functionResponse: {
        name: part.functionResponse.name,
        response: fResponse,
      },
    };
  }
  if ('inlineData' in part) {
    return {
      inlineData: {
        mimeType: part.inlineData.mimeType,
        data: part.inlineData.data,
      },
    };
  }
  return {};
}

type FunctionParam<T extends string|number|symbol = string> =
    AIDA.FunctionObjectParam<T>|AIDA.FunctionArrayParam|AIDA.FunctionPrimitiveParams;

function convertAidaParamToGcaSchema<T extends string|number|symbol = string>(param: FunctionParam<T>): GCA.Schema {
  const schema: GCA.Schema = {
    type: param.type as unknown as GCA.Type,
    description: param.description,
  };
  if (param.nullable) {
    schema.nullable = param.nullable;
  }

  if (param.type === AIDA.ParametersTypes.ARRAY && param.items) {
    schema.items = convertAidaParamToGcaSchema(param.items);
  } else if (param.type === AIDA.ParametersTypes.OBJECT && param.properties) {
    schema.properties = {};
    for (const [key, value] of Object.entries(param.properties)) {
      schema.properties[key] = convertAidaParamToGcaSchema(value as FunctionParam);
    }
    schema.required = (param.required ?? []).map(r => r.toString());
  }

  return schema;
}

export function gcaChunkResponseToAidaChunkResponse(response: GCA.GenerateContentResponse): AIDA.AidaChunkResponse[] {
  try {
    const candidate = response.candidates?.[0];
    const parts = candidate?.content?.parts || [];
    const metadata: AIDA.ResponseMetadata = {
      rpcGlobalId: response.responseId,
      inferenceOptionMetadata: {modelId: response.modelVersion}
    };

    if (candidate?.citationMetadata?.citations) {
      metadata.attributionMetadata = {
        attributionAction: AIDA.RecitationAction.CITE,
        citations: candidate.citationMetadata.citations.map(c => ({
                                                              startIndex: c.startIndex,
                                                              endIndex: c.endIndex,
                                                              uri: c.uri,
                                                            })),
      };
    }
    const chunks: AIDA.AidaChunkResponse[] = (parts).map(part => {
      const aidaChunkResponse: AIDA.AidaChunkResponse = {metadata};
      if (part.text) {
        aidaChunkResponse.textChunk = {
          text: extractTextFromGcaParts(parts),
        };
      }
      if (part.functionCall) {
        aidaChunkResponse.functionCallChunk = {
          functionCall: {
            name: part.functionCall.name,
            args: part.functionCall.args || {},
          },
        };
      }
      if (part.executableCode) {
        aidaChunkResponse.codeChunk = {
          code: part.executableCode.code,
          inferenceLanguage: part.executableCode.language ? AIDA.AidaInferenceLanguage.PYTHON :
                                                            AIDA.AidaInferenceLanguage.UNKNOWN,
        };
      }
      return aidaChunkResponse;
    });
    AIDA.debugLog('Translation succeeded:', JSON.stringify(response), JSON.stringify(chunks));
    return chunks;
  } catch (e) {
    AIDA.debugLog('Translation error', JSON.stringify(response), e);
    throw e;
  }
}