<?php

namespace app\home\controller;

use api\Httpcurl;
use app\service\SeoMetaService;
use think\facade\Log;
use think\facade\Request;
use think\facade\View;

class News extends Base
{
    public function index()
    {
        $page = intval(input('page') ? input('page') : 1);
        $size = intval(input('size') ? input('size') : 10);
        $page = max(1, $page);
        $size = max(1, $size);

        $news_list = $this->requestNewsList($page, $size);
        if (!empty($news_list) && isset($news_list['code']) && $news_list['code'] == 1) {
            $data = $this->normalizeNewsList(isset($news_list['data']) ? $news_list['data'] : []);
            $count = isset($news_list['count']) ? intval($news_list['count']) : count($data);
        } else {
            $data = [];
            $count = 0;
        }

        View::assign('data', $data);
        View::assign('count', $count);
        View::assign('page', $page);
        View::assign('size', $size);
        $this->assignSeo([
            'title' => $page > 1
                ? 'EVUS与美国签证新闻资讯 - 第' . $page . '页'
                : 'EVUS与美国签证新闻资讯',
            'canonical_path' => '/home/news/index',
            'canonical_query_keys' => ['page'],
        ]);
        return View::fetch();
    }

    public function detail()
    {
        $id = Request::instance()->param('id');
        if (
            !is_scalar($id)
            || filter_var((string) $id, FILTER_VALIDATE_INT, [
                'options' => ['min_range' => 1],
            ]) === false
        ) {
            abort(404, '新闻不存在');
        }
        $id = (int) $id;

        $info = $this->requestNewsDetail($id);
        if ($info === null) {
            abort(503, '新闻服务暂时不可用');
        }
        if (empty($info) || !isset($info['code']) || $info['code'] != 1 || empty($info['data'])) {
            abort(404, '新闻不存在');
        }

        $info_detail = $this->normalizeNewsItem($info['data']);
        $latest = $this->requestNewsList(1, 50);
        $latest_data = [];
        if (!empty($latest) && isset($latest['code']) && $latest['code'] == 1) {
            $latest_data = $this->normalizeNewsList(isset($latest['data']) ? $latest['data'] : [], true);
        }

        $nav = $this->resolveArticleNav($id, $latest_data);
        $article = $this->filterRelatedArticles($id, $latest_data, 8);

        View::assign('data', $info_detail);
        View::assign('last', $nav['last']);
        View::assign('next', $nav['next']);
        View::assign('article', $article);

        $seoService = new SeoMetaService();
        $title = $seoService->descriptionFromHtml((string) $info_detail['title'], 60);
        $description = $seoService->descriptionFromHtml(
            (string) $info_detail['contents']
        );
        $seo = [
            'canonical_path' => '/home/news/detail',
            'canonical_query_keys' => ['id'],
        ];
        if ($title !== '') {
            $seo['title'] = $title;
        }
        if ($description !== '') {
            $seo['description'] = $description;
        }
        $this->assignSeo($seo);

        return View::fetch();
    }

    private function requestNewsList($page, $size)
    {
        $response = Httpcurl::request(NEWS_LIST, 'post', [
            'model' => 'article',
            'source_code' => DOMAIN,
            'page' => $page,
            'size' => $size,
        ]);

        return $this->decodeApiResponse($response, 'news list');
    }

    private function requestNewsDetail($id)
    {
        $response = Httpcurl::request(NEWS_DETAIL, 'post', [
            'model' => 'article',
            'id' => $id,
        ]);

        return $this->decodeApiResponse($response, 'news detail');
    }

    private function decodeApiResponse($response, $scene)
    {
        if (!is_array($response) || !isset($response[0]) || !empty($response[3])) {
            Log::error($scene . ' api request failed: ' . json_encode($response));
            return null;
        }

        $status_code = intval(isset($response[2]['http_code']) ? $response[2]['http_code'] : 0);
        if ($status_code < 200 || $status_code >= 300) {
            Log::error($scene . ' api returned HTTP status: ' . $status_code);
            return null;
        }

        $result = json_decode($response[0], true);
        Log::info(json_encode($result));
        return is_array($result) ? $result : null;
    }

    private function normalizeNewsList($list, $short_date = false)
    {
        if (!is_array($list)) {
            return [];
        }

        $data = [];
        foreach ($list as $item) {
            $item = $this->normalizeNewsItem($item);
            if ($short_date) {
                $item['create_time'] = $this->formatDate($item['create_time']);
            }
            $data[] = $item;
        }

        return $data;
    }

    private function normalizeNewsItem($item)
    {
        if (!is_array($item)) {
            return [];
        }

        $item['id'] = isset($item['id']) ? $item['id'] : 0;
        $item['title'] = isset($item['title']) ? $item['title'] : '';
        $contents = isset($item['contents'])
            ? $item['contents']
            : (isset($item['content']) ? $item['content'] : '');
        $item['contents'] = is_scalar($contents)
            ? str_replace('https://www.evus.gov/', '', (string) $contents)
            : '';
        $item['create_time'] = isset($item['create_time']) ? $item['create_time'] : '';

        return $item;
    }

    private function resolveArticleNav($id, $list)
    {
        $id = intval($id);
        $last = [];
        $next = [];

        foreach ($list as $item) {
            $item_id = intval(isset($item['id']) ? $item['id'] : 0);
            if ($item_id <= 0 || $item_id == $id) {
                continue;
            }

            if ($item_id < $id && (empty($last) || $item_id > intval($last['id']))) {
                $last = $item;
            }

            if ($item_id > $id && (empty($next) || $item_id < intval($next['id']))) {
                $next = $item;
            }
        }

        return ['last' => $last, 'next' => $next];
    }

    private function filterRelatedArticles($id, $list, $limit)
    {
        $data = [];
        $id = intval($id);

        foreach ($list as $item) {
            if (intval($item['id']) == $id) {
                continue;
            }

            $data[] = $item;
            if (count($data) >= $limit) {
                break;
            }
        }

        return $data;
    }

    private function formatDate($date)
    {
        if (empty($date)) {
            return '';
        }

        $timestamp = strtotime($date);
        return $timestamp ? date('Y-m-d', $timestamp) : $date;
    }
}