<?php

namespace app\api\controller;

use think\Cache;
use app\common\BackgroundCheckService;

/**
 * 背景调查控制器
 *
 * 功能：查询学者公开学术指标 + 撤稿/不端公开记录 + 按领域批量筛查
 *
 * 接口：
 *   api/background_check/demo                 - 快速体验
 *   api/background_check/searchAuthor         - 按姓名搜索学者
 *   api/background_check/checkProfile         - 完整背景调查报告
 *   api/background_check/checkRetractionByDoi - 单篇 DOI 撤稿详情（CrossRef + RW）
 *   api/background_check/batchScreenByField   - 按领域批量筛查专家
 */
class BackgroundCheck extends Base
{
    /** @var BackgroundCheckService */
    private $service;

    public function __construct(\think\Request $request = null)
    {
        parent::__construct($request);
        $this->service = new BackgroundCheckService();
    }

    // ===================== 公开 API =====================

    /**
     * Demo：快速体验
     *
     * @param string orcid  可选，默认 0000-0002-2582-7480
     */
    public function demo()
    {
        $orcid = $this->service->cleanOrcid($this->request->param('orcid', '0000-0002-2582-7480'));

        $report = $this->buildProfileReport([
            'orcid'               => $orcid,
            'with_crossref_detail'=> 1,
        ]);
        if (!$report['success']) {
            return jsonError($report['error']);
        }

        $report['data']['_demo_note'] = 'Demo 接口，正式使用请调用 checkProfile 或 batchScreenByField';
        return jsonSuccess($report['data']);
    }

    /**
     * 按姓名搜索学者
     *
     * @param string name          学者姓名（必填）
     * @param string affiliation   单位关键词（可选）
     * @param int    limit         返回条数，默认5，最大20
     */
    public function searchAuthor()
    {
        $name = trim($this->request->param('name', ''));
        if ($name === '') {
            return jsonError('name不能为空');
        }

        $affiliation = trim($this->request->param('affiliation', ''));
        $limit = min(max(intval($this->request->param('limit', 5)), 1), 20);

        $cacheKey = 'bg_search_' . md5($name . $affiliation . $limit);
        $cached = Cache::get($cacheKey);
        if ($cached) {
            return jsonSuccess($cached);
        }

        $filter = 'display_name.search:' . $name;
        if ($affiliation !== '') {
            $filter .= ',last_known_institutions.display_name.search:' . $affiliation;
        }

        $res = $this->service->openAlexGet('/authors', [
            'search'   => $name,
            'filter'   => $filter,
            'sort'     => 'cited_by_count:desc',
            'per-page' => $limit,
        ]);

        if (!$res['success']) {
            return jsonError($res['error']);
        }

        $list = [];
        foreach ($res['data']['results'] ?? [] as $author) {
            $list[] = $this->service->formatAuthorBrief($author);
        }

        $result = [
            'query' => ['name' => $name, 'affiliation' => $affiliation],
            'total' => $res['data']['meta']['count'] ?? count($list),
            'list'  => $list,
        ];

        Cache::set($cacheKey, $result, 1800);
        return jsonSuccess($result);
    }

    /**
     * 完整背景调查报告
     *
     * @param string openalex_id         OpenAlex 作者ID
     * @param string orcid               ORCID
     * @param string name                姓名
     * @param string affiliation         单位关键词
     * @param int    user_id             本地用户ID（可选）
     * @param int    with_crossref_detail 是否补充 CrossRef 撤稿详情，默认1
     */
    public function checkProfile()
    {
        $params = [
            'openalex_id'          => trim($this->request->param('openalex_id', '')),
            'orcid'                => $this->service->cleanOrcid($this->request->param('orcid', '')),
            'name'                 => trim($this->request->param('name', '')),
            'affiliation'          => trim($this->request->param('affiliation', '')),
            'user_id'              => intval($this->request->param('user_id', 0)),
            'with_crossref_detail' => intval($this->request->param('with_crossref_detail', 1)),
        ];

        if ($params['openalex_id'] === '' && $params['orcid'] === '' && $params['name'] === '') {
            return jsonError('请至少提供 openalex_id、orcid 或 name 之一');
        }

        $report = $this->buildProfileReport($params);
        if (!$report['success']) {
            return jsonError($report['error']);
        }

        return jsonSuccess($report['data']);
    }

    /**
     * 单篇 DOI 撤稿详情（CrossRef + Retraction Watch 来源标记）
     *
     * @param string doi  文章 DOI（必填）
     */
    public function checkRetractionByDoi()
    {
        $doi = trim($this->request->param('doi', ''));
        if ($doi === '') {
            return jsonError('doi不能为空');
        }

        $res = $this->service->fetchCrossRefWork($doi);
        if (!$res['success']) {
            return jsonError($res['error']);
        }

        $detail = $this->service->parseCrossRefRetractionDetail($doi, $res['message']);
        $sources = $detail['retraction_detail']['sources'] ?? [];
        $fromRw = false;
        foreach ($sources as $src) {
            if (stripos($src, 'retraction-watch') !== false || stripos($src, 'retraction_watch') !== false) {
                $fromRw = true;
                break;
            }
        }

        return jsonSuccess([
            'doi'                   => $detail['doi'],
            'title'                 => $detail['title'],
            'journal'               => $detail['journal'],
            'publisher'             => $detail['publisher'],
            'authors'               => $detail['authors'],
            'is_retracted'          => $detail['is_retracted'],
            'from_retraction_watch' => $fromRw || !empty($detail['retraction_detail']['record_ids']),
            'retraction_detail'     => $detail['retraction_detail'],
            'url'                   => $detail['url'],
            'data_sources'          => ['CrossRef', 'Retraction Watch'],
        ]);
    }

    /**
     * 按领域批量筛查专家（含撤稿风险标签）
     *
     * @param string keyword          领域关键词（必填），如 immunotherapy、cancer
     * @param int    min_h_index      最低 h-index，默认5
     * @param int    limit            每页数量，默认10，最大30
     * @param int    page             页码，默认1
     * @param int    check_retraction  是否检查撤稿，默认1
     */
    public function batchScreenByField()
    {
        $keyword = trim($this->request->param('keyword', ''));
        if ($keyword === '') {
            return jsonError('keyword不能为空');
        }

        $options = [
            'min_h_index' => intval($this->request->param('min_h_index', 5)),
            'limit'       => min(max(intval($this->request->param('limit', 10)), 1), 30),
            'page'        => max(intval($this->request->param('page', 1)), 1),
        ];
        $checkRetraction = intval($this->request->param('check_retraction', 1));

        $cacheKey = 'bg_batch_' . md5(json_encode([$keyword, $options, $checkRetraction]));
        $cached = Cache::get($cacheKey);
        if ($cached) {
            return jsonSuccess($cached);
        }

        $searchRes = $this->service->searchAuthorsByField($keyword, $options);
        if (!$searchRes['success']) {
            return jsonError($searchRes['error']);
        }

        $data = $searchRes['data'];
        $screened = [];
        $riskStats = ['low' => 0, 'medium' => 0, 'high' => 0];

        foreach ($data['list'] as $author) {
            $item = [
                'profile' => $author,
                'metrics' => [
                    'works_count'    => $author['works_count'],
                    'cited_by_count' => $author['cited_by_count'],
                    'h_index'        => $author['h_index'],
                    'level_label'    => $this->service->parseAuthorMetrics([
                        'works_count'    => $author['works_count'],
                        'cited_by_count' => $author['cited_by_count'],
                        'summary_stats'  => ['h_index' => $author['h_index']],
                    ])['level_label'],
                ],
            ];

            if ($checkRetraction) {
                $openAlexId = $author['openalex_id'];
                $oaRetractions = $this->service->fetchRetractedWorksOpenAlex($openAlexId);
                $rwRetractions = $this->service->fetchRetractionWatchByAuthor($author['name']);
                $merged = $this->service->mergeRetractionRecords($oaRetractions, $rwRetractions, false);

                $metrics = ['works_count' => $author['works_count']];
                $risk = $this->service->assessRisk($metrics, $merged);

                $item['retractions']     = [
                    'count'         => $merged['count'],
                    'openalex_count'=> $merged['openalex_count'],
                    'rw_count'      => $merged['rw_count'],
                    'rw_only_count' => $merged['rw_only_count'],
                    'list'          => array_slice($merged['list'], 0, 3),
                ];
                $item['risk_assessment'] = $risk;
                $riskStats[$risk['level']]++;
            } else {
                $item['risk_assessment'] = [
                    'level'       => 'unknown',
                    'level_label' => '未检测',
                ];
            }

            $screened[] = $item;
            usleep(300000);
        }

        $result = [
            'query' => [
                'keyword'          => $keyword,
                'topic_id'         => $data['topic_id'],
                'min_h_index'      => $options['min_h_index'],
                'page'             => $options['page'],
                'limit'            => $options['limit'],
                'check_retraction' => $checkRetraction,
            ],
            'total'      => $data['total'],
            'risk_stats' => $checkRetraction ? $riskStats : null,
            'list'       => $screened,
            'disclaimer' => '批量筛查基于公开数据，同名作者可能存在误匹配，高风险条目需人工复核。',
        ];

        Cache::set($cacheKey, $result, 900);
        return jsonSuccess($result);
    }

    // ===================== 核心逻辑 =====================

    /**
     * 构建完整背景调查报告
     */
    private function buildProfileReport($params)
    {
        $withCrossRef = !empty($params['with_crossref_detail']);

        $author = $this->service->resolveAuthor($params);
        if (!$author['success']) {
            return $author;
        }

        $authorData = $author['data'];
        $openAlexId = $this->service->extractOpenAlexId($authorData['id']);
        $authorName = $authorData['display_name'] ?? '';

        $metrics     = $this->service->parseAuthorMetrics($authorData);
        $topics      = $this->service->parseResearchTopics($authorData);
        $recentWorks = $this->service->fetchRecentWorks($openAlexId, 5);

        // 扩展1: OpenAlex 撤稿
        $oaRetractions = $this->service->fetchRetractedWorksOpenAlex($openAlexId);

        // 扩展1: Retraction Watch 二次核对（CrossRef 来源）
        $rwRetractions = $this->service->fetchRetractionWatchByAuthor($authorName);

        // 扩展2: 合并并按需补充 CrossRef 撤稿详情
        $retractions = $this->service->mergeRetractionRecords(
            $oaRetractions,
            $rwRetractions,
            $withCrossRef
        );

        $risk = $this->service->assessRisk($metrics, $retractions);

        $localInfo = null;
        if (!empty($params['user_id'])) {
            $localInfo = $this->fetchLocalUserInfo($params['user_id']);
        }

        $dataSources = ['OpenAlex', 'Retraction Watch (via CrossRef)'];
        if ($withCrossRef) {
            $dataSources[] = 'CrossRef';
        }

        return [
            'success' => true,
            'data'    => [
                'profile'         => $this->service->formatAuthorBrief($authorData),
                'metrics'         => $metrics,
                'research_topics' => $topics,
                'recent_works'    => $recentWorks,
                'retractions'     => $retractions,
                'risk_assessment' => $risk,
                'local_info'      => $localInfo,
                'data_sources'    => $dataSources,
                'disclaimer'      => '本报告仅基于公开学术数据，不能替代正式背调或机构调查；未公开的不端行为无法检测。',
                'generated_at'    => date('Y-m-d H:i:s'),
            ],
        ];
    }

    /**
     * 合并本地用户信息
     */
    private function fetchLocalUserInfo($userId)
    {
        $user = $this->user_obj->where('user_id', $userId)->find();
        if (!$user) {
            return null;
        }

        $reviewer = $this->user_reviewer_info_obj
            ->where('reviewer_id', $userId)
            ->where('state', 0)
            ->find();

        $majors = $this->major_to_user_obj
            ->where('user_id', $userId)
            ->where('state', 0)
            ->select();

        $majorList = [];
        foreach ($majors as $m) {
            $majorList[] = [
                'major_id' => $m['major_id'],
                'path'     => getMajorStr($m['major_id']),
            ];
        }

        return [
            'user_id'  => $userId,
            'realname' => $user['realname'] ?? '',
            'email'    => $user['email'] ?? '',
            'orcid'    => $user['orcid'] ?? '',
            'company'  => $reviewer['company'] ?? '',
            'title'    => $reviewer['technical'] ?? '',
            'field'    => $reviewer['field'] ?? '',
            'majors'   => $majorList,
        ];
    }
}