package io.gitlab.jfronny.libjf.translate.api;

import io.gitlab.jfronny.libjf.LibJf;
import io.gitlab.jfronny.libjf.translate.impl.TranslateConfig;
import io.gitlab.jfronny.libjf.translate.impl.google.GoogleTranslateService;
import io.gitlab.jfronny.libjf.translate.impl.libretranslate.LibreTranslateService;
import io.gitlab.jfronny.libjf.translate.impl.noop.NoopTranslateService;

import java.io.IOException;
import java.net.URISyntaxException;
import java.util.LinkedList;
import java.util.List;

public interface TranslateService<T extends Language> {
    /**
     * Returns the TranslateService the user configured. Implementations may change without notice.
     * @return configured translation service
     */
    static TranslateService<?> getConfigured() {
        return getAvailable().stream()
                .filter(svc -> svc.getName().equals(TranslateConfig.translationService))
                .findFirst()
                .orElseGet(() -> {
                    LibJf.LOGGER.error("Falling back to NOOP translate service");
                    return NoopTranslateService.INSTANCE;
                });
    }

    /**
     * Returns all available TranslateServices. Please use getConfigured() instead where possible.
     * @return available services
     */
    static List<TranslateService<?>> getAvailable() {
        List<TranslateService<?>> result = new LinkedList<>();
        try {
            result.add(GoogleTranslateService.get());
        } catch (URISyntaxException | IOException e) {
            LibJf.LOGGER.error("Could not create Google Translate service", e);
        }
        try {
            result.add(LibreTranslateService.get(TranslateConfig.libreTranslateHost));
        } catch (TranslateException e) {
            LibJf.LOGGER.error("Could not create LibreTranslate service", e);
        }
        if (result.isEmpty()) result.add(NoopTranslateService.INSTANCE);
        return List.copyOf(result);
    }

    /**
     * Translates a string from the specified source language (or null to auto-detect) to the target language.
     * @param textToTranslate text to translate
     * @param translateFrom language to translate from. Use parseLang("auto") to detect automatically.
     * @param translateTo language to translate to. Use parseLang() to get a language by its ID
     * @return translated text
     * @throws TranslateException Something went wrong during the translation
     */
    String translate(String textToTranslate, T translateFrom, T translateTo) throws TranslateException;

    /**
     * Detects the language used in the specified string. May return "auto" if detection is unavailable.
     * @param text The text of which to detect the language
     * @return detected language
     * @throws TranslateException Something went wrong during the detection
     */
    T detect(String text) throws TranslateException;

    /**
     * Gets the language for the specified ID
     * @param lang the ID
     * @return language for the specified ID or null
     */
    T parseLang(String lang);

    /**
     * Get all available languages for the configured service.
     * @return available languages
     */
    List<T> getAvailableLanguages();

    /**
     * Get the name of this translate service.
     * @return name
     */
    String getName();
}