package com.hlab.yanalyst.domain.upload;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.http.*;
import org.springframework.stereotype.Component;
import org.springframework.web.client.RestTemplate;
import org.springframework.web.util.UriComponentsBuilder;

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.file.Path;
import java.time.Duration;
import java.time.Instant;

@Component
public class YoutubeResumableUploadClient {
    private static final String UPLOAD_URL = "https://www.googleapis.com/upload/youtube/v3/videos";
    private final RestTemplate restTemplate;
    private final ObjectMapper objectMapper;
    private final HttpClient httpClient = HttpClient.newBuilder().connectTimeout(Duration.ofSeconds(30)).build();

    public YoutubeResumableUploadClient(@Qualifier("restTemplate") RestTemplate restTemplate, ObjectMapper objectMapper) {
        this.restTemplate = restTemplate;
        this.objectMapper = objectMapper;
    }

    public String upload(String accessToken, Path file, long size, String contentType, String title,
                         String description, String privacyStatus, Instant publishAt) throws Exception {
        ObjectNode metadata = objectMapper.createObjectNode();
        metadata.putObject("snippet").put("title", title).put("description", description).put("categoryId", "22");
        ObjectNode status = metadata.putObject("status");
        status.put("privacyStatus", publishAt == null ? privacyStatus : "private");
        status.put("selfDeclaredMadeForKids", false);
        if (publishAt != null) status.put("publishAt", publishAt.toString());

        URI initiateUri = UriComponentsBuilder.fromUriString(UPLOAD_URL)
                .queryParam("uploadType", "resumable").queryParam("part", "snippet,status").build().toUri();
        HttpHeaders headers = new HttpHeaders();
        headers.setBearerAuth(accessToken);
        headers.setContentType(MediaType.APPLICATION_JSON);
        headers.set("X-Upload-Content-Type", contentType);
        headers.set("X-Upload-Content-Length", Long.toString(size));
        ResponseEntity<String> initiated = restTemplate.exchange(initiateUri, HttpMethod.POST,
                new HttpEntity<>(objectMapper.writeValueAsString(metadata), headers), String.class);
        URI sessionUri = initiated.getHeaders().getLocation();
        if (sessionUri == null) throw new IllegalStateException("YouTube 업로드 세션 주소를 받지 못했습니다.");

        HttpRequest request = HttpRequest.newBuilder(sessionUri).timeout(Duration.ofHours(2))
                .header("Authorization", "Bearer " + accessToken)
                .header("Content-Type", contentType)
                .header("Content-Length", Long.toString(size))
                .PUT(HttpRequest.BodyPublishers.ofFile(file)).build();
        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() < 200 || response.statusCode() >= 300) {
            throw new IllegalStateException("YouTube 업로드 실패 (HTTP " + response.statusCode() + "): "
                    + response.body().substring(0, Math.min(500, response.body().length())));
        }
        JsonNode result = objectMapper.readTree(response.body());
        String videoId = result.path("id").asText("");
        if (videoId.isBlank()) throw new IllegalStateException("YouTube 영상 ID를 받지 못했습니다.");
        return videoId;
    }
}