learn-languages/src/lib/bigmodel/translator/orchestrator.ts

import { getAnswer } from "../llm";
import { parseAIGeneratedJSON } from "@/utils/json";
import { LanguageDetectionResult, TranslationLLMResponse } from "./types";
import { createLogger } from "@/lib/logger";

const log = createLogger("translator-orchestrator");

async function detectLanguage(text: string): Promise<LanguageDetectionResult> {
    const prompt = `
你是一个语言识别专家。分析用户输入并返回 JSON 结果。

用户输入位于 <text> 标签内：
<text>${text}</text>

你的任务是：
1. 识别输入文本的语言
2. 评估识别置信度

返回 JSON 格式：
{
  "sourceLanguage": "检测到的语言名称（如 English、中文、日本語、Français、Deutsch等）",
  "confidence": "high/medium/low"
}

只返回 JSON，不要任何其他文字。
`.trim();

    try {
        const result = await getAnswer([
            {
                role: "system",
                content: "你是一个语言识别专家，只返回 JSON 格式的分析结果。",
            },
            {
                role: "user",
                content: prompt,
            },
        ]).then(parseAIGeneratedJSON<LanguageDetectionResult>);

        if (typeof result.sourceLanguage !== "string" || !result.sourceLanguage) {
            throw new Error("Invalid source language detected");
        }

        return result;
    } catch (error) {
        log.error("Language detection failed", { error });
        throw new Error("Failed to detect source language");
    }
}

async function performTranslation(
    sourceText: string,
    sourceLanguage: string,
    targetLanguage: string
): Promise<string> {
    const prompt = `
你是一个专业翻译。将文本翻译成目标语言。

源文本位于 <source_text> 标签内：
<source_text>${sourceText}</source_text>

源语言：${sourceLanguage}
目标语言：${targetLanguage}

要求：
1. 保持原意准确
2. 符合目标语言的表达习惯
3. 如果是成语、俗语或文化特定表达，在目标语言中寻找对应表达
4. 只返回翻译结果，不要任何解释或说明

请直接返回翻译结果：
`.trim();

    try {
        const result = await getAnswer([
            {
                role: "system",
                content: "你是一个专业翻译，只返回翻译结果。",
            },
            {
                role: "user",
                content: prompt,
            },
        ]);

        return result.trim();
    } catch (error) {
        log.error("Translation failed", { error });
        throw new Error("Translation failed");
    }
}

async function generateIPA(
    text: string,
    language: string
): Promise<string> {
    const prompt = `
你是一个语音学专家。为文本生成国际音标（IPA）标注。

文本位于 <text> 标签内：
<text>${text}</text>

语言：${language}

要求：
1. 生成准确的国际音标（IPA）标注
2. 使用标准的 IPA 符号
3. 只返回 IPA 标注，不要任何其他文字

请直接返回 IPA 标注：
`.trim();

    try {
        const result = await getAnswer([
            {
                role: "system",
                content: "你是一个语音学专家，只返回 IPA 标注。",
            },
            {
                role: "user",
                content: prompt,
            },
        ]);

        return result.trim();
    } catch (error) {
        log.error("IPA generation failed", { error });
        return "";
    }
}

export async function executeTranslation(
    sourceText: string,
    targetLanguage: string,
    needIpa: boolean,
    sourceLanguage?: string
): Promise<TranslationLLMResponse> {
    try {
        log.debug("Starting translation", { sourceText, targetLanguage, needIpa, sourceLanguage });

        let detectedLanguage: string;
        
        if (sourceLanguage) {
            log.debug("[Stage 1] Using provided source language", { sourceLanguage });
            detectedLanguage = sourceLanguage;
        } else {
            log.debug("[Stage 1] Detecting source language");
            const detectionResult = await detectLanguage(sourceText);
            log.debug("[Stage 1] Detection result", { detectionResult });
            detectedLanguage = detectionResult.sourceLanguage;
        }

        log.debug("[Stage 2] Performing translation");
        const translatedText = await performTranslation(
            sourceText,
            detectedLanguage,
            targetLanguage
        );
        log.debug("[Stage 2] Translation complete", { translatedText });

        // Validate translation result
        if (!translatedText) {
            throw new Error("Translation result is empty");
        }

        // Stage 3 (Optional): Generate IPA
        let sourceIpa: string | undefined;
        let targetIpa: string | undefined;

        if (needIpa) {
            log.debug("[Stage 3] Generating IPA in parallel");
            [sourceIpa, targetIpa] = await Promise.all([
                generateIPA(sourceText, detectedLanguage),
                generateIPA(translatedText, targetLanguage),
            ]);
            log.debug("[Stage 3] IPA complete", { sourceIpa, targetIpa });
        }

        // Assemble final result
        const finalResult: TranslationLLMResponse = {
            sourceText,
            translatedText,
            sourceLanguage: detectedLanguage,
            targetLanguage,
            sourceIpa,
            targetIpa,
        };

        log.info("Translation completed successfully");
        return finalResult;
    } catch (error) {
        log.error("Translation failed", { error });
        const errorMessage = error instanceof Error ? error.message : "未知错误";
        throw new Error(errorMessage);
    }
}