☰

Smart Translate with DeepL API

Translate selected text into another language using the DeepL API.

// ==UserScript==
// @license MIT
// @name         Smart Translate with DeepL API
// @namespace    http://tampermonkey.net/
// @version      1.3.0
// @description  Translate selected text into another language using the DeepL API.
// @author       Twil3akine
// @match        *://*/*
// @match        file:///*
// @match        ftp://*/*
// @include      myapp://*
// @connect      *
// @grant        GM_xmlhttpRequest
// @grant        GM_getValue
// @grant        GM_setValue
// ==/UserScript==

(function () {
    'use strict';

    // APIキーを取得または保存
    const getApiKey = async () => {
        let apiKey = await GM_getValue('DEEPL_API_KEY', null);
        if (!apiKey) {
            apiKey = prompt('Enter your DeepL API key:');
            if (apiKey) {
                await GM_setValue('DEEPL_API_KEY', apiKey);
            } else {
                alert('API key is required to use this script.');
            }
        }
        return apiKey;
    };

    const requestLanguage = async () => {
        const normalize = (str) => {
            return str.replace(/[Ａ-Ｚａ-ｚ]/g, (match) => {
                return String.fromCharCode(match.charCodeAt(0) - 0xFEE0);
            });
        }

        const langMap = {
            "arabic": "AR",
            "bulgarian": "BG",
            "czech": "CS",
            "danish": "DA",
            "german": "DE",
            "greek": "EL",
            "english": "EN",
            "english-british": "EN-GB",
            "english-american": "EN-US",
            "spanish": "ES",
            "estonian": "ET",
            "finnish": "FI",
            "french": "FR",
            "hungarian": "HU",
            "indonesian": "ID",
            "italian": "IT",
            "japanese": "JA",
            "korean": "KO",
            "lithuanian": "LT",
            "latvian": "LV",
            "norwegian-bokmaal": "NB",
            "dutch": "NL",
            "polish": "PL",
            "portuguese": "PT",
            "portuguese-brazilian": "PT-BR",
            "portuguese-european": "PT-PT",
            "romanian": "RO",
            "russian": "RU",
            "slovak": "SK",
            "slovenian": "SL",
            "swedish": "SV",
            "turkish": "TR",
            "ukrainian": "UK",
            "chinese": "ZH",
            "chinese-simplified": "ZH-HANS",
            "chinese-traditional": "ZH-HANT"
        };

        const input = await new Promise((resolve) => {
            const userInput = prompt('Please enter the target language for translation (e.g., English, Japanese)');
            resolve(userInput);
        });

        const formatText = normalize(input);

        // 入力があれば、対応する言語コードを返す
        const langCode = langMap[formatText.toLowerCase()];
        if (langCode) {
            return langCode;
        } else {
            alert('Invalid language entered. Defaulting to Japanese.');
        }

        return 'JA';
    };

    const translateText = async (text, lang) => {
        const apiKey = await getApiKey();
        if (!apiKey) return;

        const url = 'https://api-free.deepl.com/v2/translate';

        const params = {
            auth_key: apiKey,
            text: text,
            target_lang: lang,
        };

        GM_xmlhttpRequest({
            method: 'POST',
            url: url,
            headers: {
                'Content-Type': 'application/x-www-form-urlencoded',
            },
            data: new URLSearchParams(params).toString(),
            onload: (response) => {
                try {
                    const result = JSON.parse(response.responseText);
                    const translatedText = result.translations[0].text;
                    alert(`${text}\n\n->\n\n${translatedText}`);
                    console.log(`${text}\n\n->\n\n${translatedText}`);
                } catch (e) {
                    console.error('Error parsing the response from DeepL:', e);
                    alert('An error occurred while processing the translation.');
                }
            },
            onerror: (error) => {
                console.error('Error with DeepL API request:', error);
                alert('Error occurred while translating. Please try again later.');
            },
        });
    };

    console.log('Smart-Translate is started!');
    document.addEventListener('keydown', async (event) => {
        if (event.altKey && event.key === 't') {
            const selectedText = window.getSelection().toString().trim();
            if (selectedText) {
                await translateText(selectedText, 'JA');
            } else {
                alert('Please select text!');
            }
        }

        if (event.altKey && event.key === 'T') {
            const selectedText = window.getSelection().toString().trim();
            if (selectedText) {
                const selectLanguage = await requestLanguage();
                await translateText(selectedText, selectLanguage);
            } else {
                alert('Please select text!');
            }
        }

        if (event.altKey && event.key === 'r') {
            const apiKey = await getApiKey();
            const newKey = prompt(`Please input your new API key\nNow API key: ${apiKey}`);
            if (newKey) {
                await GM_setValue('DEEPL_API_KEY', newKey);
                alert('API key updated successfully.');
            }
        }
    });
})();