const axios = require("axios");

const DEFAULT_MODEL = process.env.OPENAI_TRANSLATION_MODEL || process.env.OPENAI_MODEL || "gpt-4o-mini";

const normalizeLanguageCode = (rawLanguage) => {
    if (!rawLanguage || typeof rawLanguage !== "string") return "en";
    const firstValue = rawLanguage.split(",")[0].trim().toLowerCase();
    if (!firstValue) return "en";
    const noQuality = firstValue.split(";")[0].trim();
    const shortCode = noQuality.split("-")[0].trim();
    return shortCode || "en";
};

const extractOutputText = (data) => {
    if (!data) return "";
    if (typeof data.output_text === "string" && data.output_text.trim()) {
        return data.output_text.trim();
    }
    if (!Array.isArray(data.output)) return "";
    const chunks = [];
    data.output.forEach((item) => {
        if (!Array.isArray(item?.content)) return;
        item.content.forEach((entry) => {
            if (entry?.type === "output_text" && typeof entry?.text === "string") {
                chunks.push(entry.text);
            }
        });
    });
    return chunks.join("\n").trim();
};

const translateText = async ({ text, sourceLang, targetLang }) => {
    const normalizedSource = normalizeLanguageCode(sourceLang);
    const normalizedTarget = normalizeLanguageCode(targetLang);
    if (!text || !normalizedTarget || normalizedSource === normalizedTarget) {
        return {
            translatedText: text,
            provider: "none",
            model: "none",
        };
    }

    const apiKey = process.env.OPENAI_API_KEY;
    if (!apiKey) return null;

    try {
        const response = await axios.post(
            "https://api.openai.com/v1/responses",
            {
                model: DEFAULT_MODEL,
                input: [
                    {
                        role: "system",
                        content: [
                            {
                                type: "input_text",
                                text: "You translate chat messages and posts. Keep meaning, tone, emojis, names, and references. Do not translate structural tags starting with @ (e.g. @image:..., @youtube:..., @bible:...). Leave them exactly as they are or omit them if they do not fit the text flow. Return only the translated text.",
                            },
                        ],
                    },
                    {
                        role: "user",
                        content: [
                            {
                                type: "input_text",
                                text: `Translate this message from ${normalizedSource} to ${normalizedTarget}:\n\n${text}`,
                            },
                        ],
                    },
                ],
            },
            {
                timeout: 15000,
                headers: {
                    "Content-Type": "application/json",
                    Authorization: `Bearer ${apiKey}`,
                },
            }
        );

        const translatedText = extractOutputText(response?.data);
        if (!translatedText) return null;
        return {
            translatedText,
            provider: "openai",
            model: DEFAULT_MODEL,
        };
    } catch (error) {
        console.error("Error translating chat message", error?.response?.data || error?.message || error);
        return null;
    }
};

module.exports = {
    normalizeLanguageCode,
    translateText,
};