import json
import urllib.parse
import urllib.request


def translate_mymemory(text, source="zh-CN", target="es"):
    url = (
        "https://api.mymemory.translated.net/get?"
        + urllib.parse.urlencode({"q": text, "langpair": source + "|" + target})
    )
    try:
        with urllib.request.urlopen(url, timeout=15) as resp:
            data = json.loads(resp.read().decode("utf-8"))
        translated = data.get("responseData", {}).get("translatedText", "")
        if not translated or data.get("quotaFinished"):
            return {"ok": False, "error": "MyMemory 配额已用完或未返回结果"}
        return {"ok": True, "translatedText": translated, "provider": "mymemory"}
    except Exception as exc:
        return {"ok": False, "error": str(exc)}


def translate_custom(text, settings, source="zh", target="es"):
    api_url = (settings.get("api_url") or "").strip()
    if not api_url:
        return {"ok": False, "error": "未配置自定义翻译接口地址"}

    extra = {}
    try:
        extra = json.loads(settings.get("extra_config") or "{}")
    except Exception:
        extra = {}

    payload = extra.get("payload", {})
    payload["q"] = text
    payload["source"] = source
    payload["target"] = target

    headers = {"Content-Type": "application/json"}
    api_key = settings.get("api_key") or ""
    header_key = extra.get("api_key_header", "Authorization")
    if api_key:
        headers[header_key] = api_key
    headers.update(extra.get("headers", {}) or {})

    request = urllib.request.Request(
        api_url,
        data=json.dumps(payload).encode("utf-8"),
        headers=headers,
        method="POST",
    )
    try:
        with urllib.request.urlopen(request, timeout=20) as resp:
            data = json.loads(resp.read().decode("utf-8"))
        text_key = extra.get("result_key", "translatedText")
        translated = data
        for part in text_key.split("."):
            if isinstance(translated, dict):
                translated = translated.get(part, "")
            else:
                translated = ""
        if not translated:
            return {"ok": False, "error": "自定义接口未返回可识别的翻译字段"}
        return {"ok": True, "translatedText": translated, "provider": "custom"}
    except Exception as exc:
        return {"ok": False, "error": str(exc)}


def perform_translate(text, settings, source="zh", target="es"):
    provider = (settings.get("translator") or "local").lower()
    if provider == "mymemory":
        lang_map = {
            ("zh", "es"): ("zh-CN", "es"),
            ("es", "zh"): ("es", "zh-CN"),
            ("zh", "en"): ("zh-CN", "en"),
            ("en", "zh"): ("en", "zh-CN"),
            ("es", "en"): ("es", "en"),
            ("en", "es"): ("en", "es"),
        }
        src, dst = lang_map.get((source, target), (source, target))
        return translate_mymemory(text, src, dst)
    if provider == "custom":
        return translate_custom(text, settings, source, target)
    return {"ok": False, "error": "本地词典翻译请在前端完成"}