<?php

namespace app\common\mq;

use think\Db;
use app\common\DbReconnectHelper;
use app\common\ReferenceRelevanceCheckService;

/**
 * RabbitMQ 消费（队列 reference_check / ref_check.article）：
 * 全局文章串行，文章内 reference_no 升序链式逐条「主题相关性」校对。
 */
class ReferenceCheckArticleWorker
{
  const BATCH_WAITING = 0;
  const BATCH_RUNNING = 1;
  const BATCH_DONE = 2;
  const BATCH_PARTIAL_FAILED = 3;

  /** @var ReferenceRelevanceCheckService */
  private $svc;

  public function __construct()
  {
    $this->svc = new ReferenceRelevanceCheckService();
  }

  public function handleMessage(array $payload)
  {
    DbReconnectHelper::ensure();
    $pArticleId = intval(isset($payload['p_article_id']) ? $payload['p_article_id'] : 0);
    $batchId = intval(isset($payload['batch_id']) ? $payload['batch_id'] : 0);
    $trigger = isset($payload['trigger']) ? (string)$payload['trigger'] : 'enqueue';
    if ($pArticleId <= 0 || $batchId <= 0) {
      $this->svc->log('ReferenceCheckArticleWorker invalid payload');
      return;
    }

    if (!$this->canStartArticleWork($batchId)) {
      $this->svc->log('ReferenceCheckArticleWorker defer batch_id=' . $batchId . ' other article running');
      (new ReferenceCheckMqPublisher())->publishArticleStart(
        $pArticleId,
        $batchId,
        isset($payload['trigger']) ? $payload['trigger'] : 'enqueue'
      );
      sleep(3);
      return;
    }

    if (!$this->claimBatch($batchId)) {
      $batch = $this->getBatch($batchId);
      // 已被其他消费者领取或已结束，当前消息直接跳过，避免同批次并发重复执行
      if (empty($batch)
          || intval($batch['batch_status']) === self::BATCH_RUNNING
          || intval($batch['batch_status']) === self::BATCH_DONE
          || intval($batch['batch_status']) === self::BATCH_PARTIAL_FAILED) {
        return;
      }
    }

    $this->svc->recoverQueueRowsForArticle($pArticleId);
    if ($trigger !== 'recheck_pending_only'
        && ReferenceRelevanceCheckService::PREPARE_LITERATURE_BEFORE_CHECK) {
      $this->svc->prepareLiteratureContentByArticle($pArticleId);
    }
    $this->svc->log('ReferenceCheckArticleWorker start p_article_id=' . $pArticleId . ' batch_id=' . $batchId);

    // 快照本批待处理 id：联合引用组长一次会整组落库，循环计数会小于 total_count，收尾按快照回填
    $trackedIds = $this->listPendingCheckIds($pArticleId);
    $done = 0;
    $failed = 0;
    while (true) {
      $row = $this->fetchNextPendingRow($pArticleId);
      if (empty($row)) {
        break;
      }
      $checkId = $this->svc->resolveCheckRowId($row);
      if ($checkId <= 0) {
        continue;
      }
      $result = $this->processOneRow($checkId, $row, $trigger === 'recheck_pending_only');
      if ($result === 'ok') {
        $done++;
      } elseif ($result === 'failed') {
        $failed++;
      }
    }

    if (!empty($trackedIds)) {
      $stats = $this->summarizeTrackedCheckIds($trackedIds);
      $done = intval($stats['done']);
      $failed = intval($stats['failed']);
    }
    $this->finalizeBatch($batchId, $done, $failed);
    $this->svc->log('ReferenceCheckArticleWorker done p_article_id=' . $pArticleId . ' batch_id=' . $batchId . ' done=' . $done . ' failed=' . $failed);

    $this->publishNextWaitingBatch();
  }

  private function listPendingCheckIds($pArticleId)
  {
    $rows = Db::name('article_reference_relevance_check_result')
      ->where('p_article_id', intval($pArticleId))
      ->where('queue_status', ReferenceRelevanceCheckService::QUEUE_PENDING)
      ->where('status', ReferenceRelevanceCheckService::RECORD_PENDING)
      ->field('id')
      ->select();
    $ids = [];
    foreach ($rows as $row) {
      $id = intval(isset($row['id']) ? $row['id'] : 0);
      if ($id > 0) {
        $ids[] = $id;
      }
    }
    return $ids;
  }

  private function summarizeTrackedCheckIds(array $checkIds)
  {
    $checkIds = array_values(array_filter(array_map('intval', $checkIds)));
    if (empty($checkIds)) {
      return ['done' => 0, 'failed' => 0];
    }
    $rows = Db::name('article_reference_relevance_check_result')
      ->whereIn('id', $checkIds)
      ->field('id,status')
      ->select();
    $done = 0;
    $failed = 0;
    foreach ($rows as $row) {
      $st = intval(isset($row['status']) ? $row['status'] : -1);
      if ($st === ReferenceRelevanceCheckService::RECORD_COMPLETED) {
        $done++;
      } elseif ($st === ReferenceRelevanceCheckService::RECORD_FAILED) {
        $failed++;
      }
    }
    return ['done' => $done, 'failed' => $failed];
  }

  private function canStartArticleWork($batchId)
  {
    $running = Db::name('article_reference_relevance_check_batch')
      ->where('batch_status', self::BATCH_RUNNING)
      ->where('id', '<>', intval($batchId))
      ->count();
    return intval($running) === 0;
  }

  private function claimBatch($batchId)
  {
    $now = date('Y-m-d H:i:s');
    $affected = Db::name('article_reference_relevance_check_batch')
      ->where('id', intval($batchId))
      // 只允许 WAITING -> RUNNING，禁止已 RUNNING 的批次被重复 claim
      ->where('batch_status', self::BATCH_WAITING)
      ->update([
        'batch_status' => self::BATCH_RUNNING,
        'updated_at'   => $now,
      ]);
    return intval($affected) > 0;
  }

  private function getBatch($batchId)
  {
    return Db::name('article_reference_relevance_check_batch')->where('id', intval($batchId))->find();
  }

  private function fetchNextPendingRow($pArticleId)
  {
    return Db::name('article_reference_relevance_check_result')
      ->where('p_article_id', intval($pArticleId))
      ->where('queue_status', ReferenceRelevanceCheckService::QUEUE_PENDING)
      ->where('status', ReferenceRelevanceCheckService::RECORD_PENDING)
      ->order('reference_no asc,am_id asc,text_start asc,id asc')
      ->find();
  }

  /**
   * @return string ok|failed|skip
   */
  private function processOneRow($checkId, array $row, $skipLiteratureFetch = false)
  {
    DbReconnectHelper::ensure();
    $claimed = Db::name('article_reference_relevance_check_result')
      ->where('id', intval($checkId))
      ->where('queue_status', ReferenceRelevanceCheckService::QUEUE_PENDING)
      ->update(['queue_status' => ReferenceRelevanceCheckService::QUEUE_RUNNING]);
    if (intval($claimed) <= 0) {
      return 'skip';
    }

    $retryCount = intval(isset($row['retry_count']) ? $row['retry_count'] : 0);
    try {
      $this->svc->runCheckOnce($checkId, $skipLiteratureFetch);
      $this->svc->markQueueRuntime($checkId, ReferenceRelevanceCheckService::QUEUE_COMPLETED, $retryCount);
      return 'ok';
    } catch (\Exception $e) {
      $this->svc->log('ReferenceCheckArticleWorker check_id=' . $checkId . ' err=' . $e->getMessage());
      DbReconnectHelper::ensure();
      try {
        $fresh = Db::name('article_reference_relevance_check_result')->where('id', intval($checkId))->find();
        if (!empty($fresh) && intval($fresh['status']) === ReferenceRelevanceCheckService::RECORD_FAILED) {
          if (intval($fresh['queue_status']) !== ReferenceRelevanceCheckService::QUEUE_FAILED) {
            $this->svc->markQueueRuntime($checkId, ReferenceRelevanceCheckService::QUEUE_FAILED, $retryCount);
          }
          return 'failed';
        }
        $groupRows = !empty($fresh) ? $this->svc->findCitationGroupRowsForWorker($fresh) : [];
        if (!empty($groupRows)) {
          $this->svc->failGroupWithQueue($groupRows, $e->getMessage(), $retryCount);
        } else {
          $this->svc->updateCheckResult($checkId, [
            'status'    => ReferenceRelevanceCheckService::RECORD_FAILED,
            'error_msg' => $e->getMessage(),
          ]);
          $this->svc->markQueueRuntime($checkId, ReferenceRelevanceCheckService::QUEUE_FAILED, $retryCount);
        }
      } catch (\Exception $e2) {
        \think\Log::error('ReferenceCheckArticleWorker markFailed: ' . $e2->getMessage());
      }
      return 'failed';
    }
  }

  private function finalizeBatch($batchId, $done, $failed)
  {
    $batch = $this->getBatch($batchId);
    if (empty($batch)) {
      return;
    }
    $total = intval($batch['total_count']);
    $done = intval($done);
    $failed = intval($failed);
    // 快照回填后若实际终态条数多于入队 total，抬升 total 保持一致
    if (($done + $failed) > $total) {
      $total = $done + $failed;
    }
    $status = self::BATCH_DONE;
    if ($failed > 0) {
      $status = self::BATCH_PARTIAL_FAILED;
    }
    Db::name('article_reference_relevance_check_batch')->where('id', intval($batchId))->update([
      'batch_status' => $status,
      'total_count'  => $total,
      'done_count'   => $done,
      'failed_count' => $failed,
      'updated_at'   => date('Y-m-d H:i:s'),
    ]);
    if ($total > 0 && ($done + $failed) < $total) {
      $this->svc->log('ReferenceCheckArticleWorker batch_id=' . $batchId . ' incomplete total=' . $total . ' done=' . $done . ' failed=' . $failed);
    }
  }

  private function publishNextWaitingBatch()
  {
    $next = Db::name('article_reference_relevance_check_batch')
      ->where('batch_status', self::BATCH_WAITING)
      ->order('id asc')
      ->find();
    if (empty($next)) {
      return;
    }
    try {
      (new ReferenceCheckMqPublisher())->publishArticleStart(
        intval($next['p_article_id']),
        intval($next['id']),
        isset($next['trigger']) ? $next['trigger'] : 'enqueue'
      );
    } catch (\Exception $e) {
      $this->svc->log('ReferenceCheck publishNextWaitingBatch failed: ' . $e->getMessage());
      \think\Log::error('ReferenceCheck publishNextWaitingBatch: ' . $e->getMessage());
    }
  }
}