/*
 * Copyright (C) 2008-2023, Juick
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.juick.service;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.juick.www.api.webfinger.Resource;
import com.juick.www.api.webfinger.model.Account;
import com.juick.www.api.webfinger.model.Link;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import org.apache.commons.lang3.StringUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Component;
import org.springframework.web.util.UriComponentsBuilder;
import rocks.xmpp.addr.Jid;

import javax.inject.Inject;
import java.io.IOException;
import java.net.URI;

@Component
public class WebfingerService {
    private final OkHttpClient httpClient;
    private final ObjectMapper jsonMapper;
    @Inject
    public WebfingerService(final OkHttpClient httpClient, final ObjectMapper jsonMapper) {
        this.httpClient = httpClient;
        this.jsonMapper = jsonMapper;
    }
    public URI discoverAccountURI(String acct, MediaType linkType) {
        Jid acctId = Jid.of(acct);
        var resourceUri = UriComponentsBuilder.fromPath("/.well-known/webfinger").host(acctId.getDomain())
                .scheme("https").queryParam("resource", "acct:" + acct).build().toUriString();
        var request = new Request.Builder()
                .url(resourceUri)
                .addHeader(HttpHeaders.ACCEPT, Resource.MEDIA_TYPE)
                .build();
        try {
            try(var response = httpClient.newCall(request).execute()) {
                if (response.isSuccessful() && response.body() != null) {
                    var account = jsonMapper.readValue(response.body().string(), Account.class);
                    for (Link l : account.links()) {
                        if (l.rel().equals("self") && l.type().equals(linkType.toString())) {
                            return URI.create(l.href());
                        }
                    }
                }
            }
        } catch (IOException e) {
            return URI.create(StringUtils.EMPTY);
        }
        return URI.create(StringUtils.EMPTY);
    }
}