<?php

namespace App\Services\Crawl;

use App\Models\CrawlJob;
use App\Models\CrawlJobItem;
use App\Models\CrawlSource;
use App\Models\News;
use App\Models\Paper;
use App\Models\Teacher;

class CrawlJobRunnerService
{
    public function __construct(
        protected CrawlJobDispatcher $dispatcher,
    ) {}

    /**
     * @param  array<string, mixed>  $params
     */
    public function run(CrawlJob $job, CrawlSource $source, array $params): CrawlJob
    {
        $job->update(['status' => 'running']);

        $dtos = $this->dispatcher->fetch(
            $job->request_url ?? $job->platform_url,
            $source,
            $params
        );

        $count = 0;
        foreach ($dtos as $dto) {
            if ($source->target_type === 'teacher') {
                $count += $this->persistTeacherItem($job, $source, $dto) ? 1 : 0;

                continue;
            }

            $status = $this->previewStatusForPaperOrNews($source, $dto);
            $payload = $this->buildPayload($dto);

            CrawlJobItem::query()->updateOrCreate(
                [
                    'crawl_job_id' => $job->id,
                    'external_id' => $dto->externalId,
                ],
                [
                    'canonical_url' => $dto->canonicalUrl,
                    'title' => $dto->title,
                    'payload' => $payload,
                    'status' => $status,
                    'target_type' => $source->target_type === 'paper' ? 'paper' : 'news',
                    'source_name' => $source->name,
                    'target_id' => null,
                ]
            );
            $count++;

            if ($source->target_type === 'paper') {
                $this->persistTeacherLeadItem($job, $source, $dto, $payload, $status);
            }
        }

        $job->update([
            'status' => 'completed',
            'items_fetched' => $count,
            'papers_created' => $source->target_type === 'paper' ? $count : 0,
            'result_summary' => sprintf('已从 %s 抓取 %d 条（暂存预览，请勾选入库）', $source->name, $count),
            'completed_at' => now(),
        ]);

        return $job->fresh();
    }

    protected function previewStatusForPaperOrNews(CrawlSource $source, CrawlItemDto $dto): string
    {
        if ($source->target_type === 'paper') {
            if (Paper::query()
                ->where('external_id', $dto->externalId)
                ->where('source', 'crawl')
                ->exists()) {
                return 'duplicate';
            }
        } else {
            $url = $dto->canonicalUrl;
            if ($url && News::query()->where('source_url', $url)->exists()) {
                return 'duplicate';
            }
        }

        return 'preview';
    }

    /**
     * @return array<string, mixed>
     */
    protected function buildPayload(CrawlItemDto $dto): array
    {
        $extra = $dto->extra;
        if ($dto->authorsParsed !== []) {
            $extra['authors_parsed'] = $dto->authorsParsed;
        }
        if (! isset($extra['lead_author'])) {
            $extra['lead_author'] = CrawlAuthorParser::leadAuthor($dto->authors, $dto->authorsParsed);
        }

        return [
            'authors' => $dto->authors,
            'summary' => $dto->summary,
            'published_at' => $dto->publishedAt,
            'school_name' => $dto->schoolName,
            'section' => $dto->section,
            'content_html' => $dto->contentHtml,
            'extra' => $extra,
            'authors_parsed' => $dto->authorsParsed,
            'lead_author' => $extra['lead_author'] ?? null,
        ];
    }

    /**
     * @param  array<string, mixed>  $paperPayload
     */
    protected function persistTeacherLeadItem(
        CrawlJob $job,
        CrawlSource $source,
        CrawlItemDto $dto,
        array $paperPayload,
        string $paperStatus,
    ): void {
        $lead = $paperPayload['lead_author'] ?? null;
        if (! is_array($lead) || trim((string) ($lead['name'] ?? '')) === '') {
            return;
        }

        $leadExternalId = 'lead:'.$dto->externalId;
        $dup = false;
        if (! empty($lead['email']) && Teacher::query()->where('email', $lead['email'])->exists()) {
            $dup = true;
        }

        CrawlJobItem::query()->updateOrCreate(
            [
                'crawl_job_id' => $job->id,
                'external_id' => $leadExternalId,
            ],
            [
                'canonical_url' => $dto->canonicalUrl,
                'title' => (string) $lead['name'],
                'payload' => [
                    'lead_author' => $lead,
                    'paper_external_id' => $dto->externalId,
                    'paper_title' => $dto->title,
                    'school_name' => $lead['university_name'] ?? $dto->schoolName,
                ],
                'status' => $dup ? 'duplicate' : ($paperStatus === 'duplicate' ? 'preview' : 'preview'),
                'target_type' => 'teacher_lead',
                'source_name' => $source->name,
                'target_id' => null,
            ]
        );
    }

    protected function persistTeacherItem(CrawlJob $job, CrawlSource $source, CrawlItemDto $dto): bool
    {
        $lead = $dto->extra['lead_author'] ?? CrawlAuthorParser::leadAuthor($dto->authors, $dto->authorsParsed);
        $email = is_array($lead) ? ($lead['email'] ?? null) : null;
        $status = 'preview';
        if ($email && Teacher::query()->where('email', $email)->exists()) {
            $status = 'duplicate';
        }

        CrawlJobItem::query()->updateOrCreate(
            [
                'crawl_job_id' => $job->id,
                'external_id' => $dto->externalId,
            ],
            [
                'canonical_url' => $dto->canonicalUrl,
                'title' => $dto->title,
                'payload' => [
                    'lead_author' => $lead,
                    'school_name' => $dto->schoolName,
                    'summary' => $dto->summary,
                ],
                'status' => $status,
                'target_type' => 'teacher',
                'source_name' => $source->name,
                'target_id' => null,
            ]
        );

        return true;
    }
}