Textractor/extensions/deepltranslate.cpp

#include "qtcommon.h"
#include "translatewrapper.h"
#include "network.h"
#include <random>

extern const wchar_t* TRANSLATION_ERROR;

const char* TRANSLATION_PROVIDER = "DeepL Translate";
const char* GET_API_KEY_FROM = "https://www.deepl.com/pro.html";
extern const QStringList languagesTo
{
	"Bulgarian",
	"Chinese (Simplified)",
	"Czech",
	"Danish",
	"Dutch",
	"English (American)",
	"English (British)",
	"Estonian",
	"Finnish",
	"French",
	"German",
	"Greek",
	"Hungarian",
	"Italian",
	"Japanese",
	"Latvian",
	"Lithuanian",
	"Polish",
	"Portuguese (Brazil)",
	"Portuguese (Portugal)",
	"Romanian",
	"Russian",
	"Slovak",
	"Slovenian",
	"Spanish",
	"Swedish"
},
languagesFrom
{
	"Bulgarian",
	"Chinese",
	"Czech",
	"Danish",
	"Dutch",
	"English",
	"Estonian",
	"Finnish",
	"French",
	"German",
	"Greek",
	"Hungarian",
	"Italian",
	"Japanese",
	"Latvian",
	"Lithuanian",
	"Polish",
	"Portuguese",
	"Romanian",
	"Russian",
	"Slovak",
	"Slovenian",
	"Spanish",
	"Swedish"
};
extern const std::unordered_map<std::wstring, std::wstring> codes
{
	{ { L"Bulgarian" }, { L"BG" } },
	{ { L"Chinese" }, { L"ZH" } },
	{ { L"Chinese (Simplified)" }, { L"ZH" } },
	{ { L"Czech" }, { L"CS" } },
	{ { L"Danish" }, { L"DA" } },
	{ { L"Dutch" }, { L"NL" } },
	{ { L"English" }, { L"EN" } },
	{ { L"English (American)" }, { L"EN-US" } },
	{ { L"English (British)" }, { L"EN-GB" } },
	{ { L"Estonian" }, { L"ET" } },
	{ { L"Finnish" }, { L"FI" } },
	{ { L"French" }, { L"FR" } },
	{ { L"German" }, { L"DE" } },
	{ { L"Greek" }, { L"EL" } },
	{ { L"Hungarian" }, { L"HU" } },
	{ { L"Italian" }, { L"IT" } },
	{ { L"Japanese" }, { L"JA" } },
	{ { L"Latvian" }, { L"LV" } },
	{ { L"Lithuanian" }, { L"LT" } },
	{ { L"Polish" }, { L"PL" } },
	{ { L"Portuguese" }, { L"PT" } },
	{ { L"Portuguese (Brazil)" }, { L"PT-BR" } },
	{ { L"Portuguese (Portugal)" }, { L"PT-PT" } },
	{ { L"Romanian" }, { L"RO" } },
	{ { L"Russian" }, { L"RU" } },
	{ { L"Slovak" }, { L"SK" } },
	{ { L"Slovenian" }, { L"SL" } },
	{ { L"Spanish" }, { L"ES" } },
	{ { L"Swedish" }, { L"SV" } },
	{ { L"?" }, { L"auto" } }
};

bool translateSelectedOnly = true, rateLimitAll = true, rateLimitSelected = true, useCache = true, useFilter = true;
int tokenCount = 10, tokenRestoreDelay = 60000, maxSentenceSize = 1000;

enum KeyType { CAT, REST };
int keyType = REST;

std::pair<bool, std::wstring> Translate(const std::wstring& text, TranslationParam tlp)
{
	if (!tlp.authKey.empty())
	{
		std::string translateFromComponent = tlp.translateFrom == L"?" ? "" : "&source_lang=" + WideStringToString(codes.at(tlp.translateFrom));
		if (HttpRequest httpRequest{
			L"Mozilla/5.0 Textractor",
			tlp.authKey.find(L":fx") == std::string::npos ? L"api.deepl.com" : L"api-free.deepl.com",
			L"POST",
			keyType == CAT ? L"/v1/translate" : L"/v2/translate",
			FormatString("text=%S&auth_key=%S&target_lang=%S", Escape(text), tlp.authKey, codes.at(tlp.translateTo)) + translateFromComponent,
			L"Content-Type: application/x-www-form-urlencoded"
		}; httpRequest && (httpRequest.response.find(L"translations") != std::string::npos || (httpRequest = HttpRequest{
			L"Mozilla/5.0 Textractor",
			tlp.authKey.find(L":fx") == std::string::npos ? L"api.deepl.com" : L"api-free.deepl.com",
			L"POST",
			(keyType = !keyType) == CAT ? L"/v1/translate" : L"/v2/translate",
			FormatString("text=%S&auth_key=%S&target_lang=%S", Escape(text), tlp.authKey, codes.at(tlp.translateTo)) + translateFromComponent,
			L"Content-Type: application/x-www-form-urlencoded"
		})))
			// Response formatted as JSON: translation starts with text":" and ends with "}]
			if (auto translation = Copy(JSON::Parse(httpRequest.response)[L"translations"][0][L"text"].String())) return { true, translation.value() };
			else return { false, FormatString(L"%s: %s", TRANSLATION_ERROR, httpRequest.response) };
		else return { false, FormatString(L"%s (code=%u)", TRANSLATION_ERROR, httpRequest.errorCode) };
	}

	// the following code was reverse engineered from the DeepL website; it's as close as I could make it but I'm not sure what parts of this could be removed and still have it work
	int64_t r = _time64(nullptr), n = std::count(text.begin(), text.end(), L'i') + 1;
	thread_local auto generator = std::mt19937(std::random_device()());
	int id = 10000 * std::uniform_int_distribution(0, 9999)(generator) + 1;
	// user_preferred_langs? what should priority be? does timestamp do anything? other translation quality options?
	auto body = FormatString(R"(
{
	"id": %d,
	"jsonrpc": "2.0",
	"method": "LMT_handle_jobs",
	"params": {
		"priority": -1,
		"timestamp": %lld,
		"lang": {
			"target_lang": "%.2S",
			"source_lang_user_selected": "%S"
		},
		"jobs": [{
			"raw_en_sentence": "%s",
			"raw_en_context_before": [],
			"kind": "default",
			"preferred_num_beams": 1,
			"quality": "fast",
			"raw_en_context_after": []
		}]
	}
}
	)", id, r + (n - r % n), codes.at(tlp.translateTo), codes.at(tlp.translateFrom), JSON::Escape(WideStringToString(text)));
	// missing accept-encoding header since it fucks up HttpRequest
	if (HttpRequest httpRequest{
		L"Mozilla/5.0 Textractor",
		L"www2.deepl.com",
		L"POST",
		L"/jsonrpc",
		body,
		L"Host: www2.deepl.com\r\nAccept-Language: en-US,en;q=0.5\r\nContent-type: application/json; charset=utf-8\r\nOrigin: https://www.deepl.com\r\nTE: Trailers",
		INTERNET_DEFAULT_PORT,
		L"https://www.deepl.com/translator",
		WINHTTP_FLAG_SECURE
	})
		if (auto translation = Copy(JSON::Parse(httpRequest.response)[L"result"][L"translations"][0][L"beams"][0][L"postprocessed_sentence"].String())) return { true, translation.value() };
		else return { false, FormatString(L"%s: %s", TRANSLATION_ERROR, httpRequest.response) };
	else return { false, FormatString(L"%s (code=%u)", TRANSLATION_ERROR, httpRequest.errorCode) };
}