/**
 * Analyzer job worker.
 *
 * Polls `analyzer_jobs` for queued rows, runs the full pipeline, persists the
 * result, and updates the job's status / result_analysis_id throughout.
 *
 * Concurrency model: a single in-process polling loop. Multiple Next.js
 * workers will all import this module, but `claimQueuedJob()` uses
 * `FOR UPDATE SKIP LOCKED` so they cooperate at the row level — each job is
 * processed exactly once.
 *
 * Auto-start: the worker self-initializes on first server-side import in
 * production. In dev / tests, set ANALYZER_WORKER_AUTOSTART=1 to opt in.
 */

import {
  claimQueuedJob,
  completeJob,
  failJob,
  insertAnalysis,
  updateJobStatus,
} from './persistence';
import { loadTicketBundle, TicketNotFoundError } from './data-access';
import { runPipeline, type PipelineResult } from './pipeline';

const POLL_INTERVAL_MS = 2_000;

class AnalyzerWorker {
  private timer: NodeJS.Timeout | null = null;
  private running = false;
  private inFlight = false;

  async start(): Promise<void> {
    if (this.running) return;
    this.running = true;
    console.log('[ANALYZER-WORKER] starting; polling every 2s');
    this.scheduleNextPoll(0);
  }

  async stop(): Promise<void> {
    this.running = false;
    if (this.timer) {
      clearTimeout(this.timer);
      this.timer = null;
    }
  }

  private scheduleNextPoll(delay: number): void {
    if (!this.running) return;
    this.timer = setTimeout(() => {
      void this.poll();
    }, delay);
  }

  private async poll(): Promise<void> {
    if (!this.running) return;
    if (this.inFlight) {
      // Avoid overlap if a previous poll is still running.
      this.scheduleNextPoll(POLL_INTERVAL_MS);
      return;
    }
    this.inFlight = true;
    try {
      const claimed = await claimQueuedJob();
      if (claimed) {
        await this.runJob(claimed.id, claimed.ticket_number, claimed.queued_by_user_id);
      }
    } catch (err) {
      console.error('[ANALYZER-WORKER] poll error:', err);
    } finally {
      this.inFlight = false;
      this.scheduleNextPoll(POLL_INTERVAL_MS);
    }
  }

  /**
   * Process a single job end-to-end. Public so tests + manual triggers can
   * call it directly without going through the poll loop.
   */
  async runJob(
    jobId: string,
    ticketNumber: string,
    triggeredByUserId: string | null
  ): Promise<{ analysis_id: string | null; outcome: PipelineResult['outcome'] | 'failed' }> {
    try {
      const bundle = await loadTicketBundle(ticketNumber);

      const result = await runPipeline(
        { bundle, force: false },
        {},
        {
          onStage: (stage) => updateJobStatus(jobId, stage),
        }
      );

      if (result.outcome === 'idempotent_short_circuit') {
        // Point the job at the existing analysis so the UI can navigate to it.
        await completeJob(jobId, result.existing_analysis_id);
        return {
          analysis_id: result.existing_analysis_id,
          outcome: 'idempotent_short_circuit',
        };
      }

      const inserted = await insertAnalysis({
        ticket_number: result.pre.header.ticket_number,
        autotask_ticket_id: result.pre.header.autotask_ticket_id,
        content_hash: result.pre.content_hash,
        triggered_by_user_id: triggeredByUserId,
        status: 'complete',
        haiku_used: result.meta.haiku_used,
        sonnet_used: result.meta.sonnet_used,
        opus_used: result.meta.opus_used,
        total_input_tokens: result.meta.total_input_tokens,
        total_output_tokens: result.meta.total_output_tokens,
        estimated_cost_usd: result.meta.estimated_cost_usd,
        analysis: result.analysis,
        filtered_noise_count: result.filtered_noise_count,
        model_traces: result.model_traces,
      });

      await completeJob(jobId, inserted.id);
      return { analysis_id: inserted.id, outcome: 'complete' };
    } catch (err) {
      const message = err instanceof Error ? err.message : String(err);
      console.error(
        `[ANALYZER-WORKER] job ${jobId} (${ticketNumber}) failed:`,
        message
      );
      const reason =
        err instanceof TicketNotFoundError
          ? `Ticket ${ticketNumber} not found in local mirror — confirm sync is current.`
          : message;
      await failJob(jobId, reason);
      return { analysis_id: null, outcome: 'failed' };
    }
  }
}

export const analyzerWorker = new AnalyzerWorker();

/**
 * Should we auto-start the worker on import?
 *   - Skip in browsers (typeof window check).
 *   - Skip during vitest.
 *   - Auto-start in production by default.
 *   - Otherwise opt in via ANALYZER_WORKER_AUTOSTART=1.
 */
function shouldAutoStart(): boolean {
  if (typeof window !== 'undefined') return false;
  if (process.env.VITEST === 'true') return false;
  if (process.env.NODE_ENV === 'production') return true;
  return process.env.ANALYZER_WORKER_AUTOSTART === '1';
}

if (shouldAutoStart()) {
  analyzerWorker.start().catch((err) => {
    console.error('[ANALYZER-WORKER] failed to auto-start:', err);
  });
}

export const _WORKER_INTERNALS = { POLL_INTERVAL_MS };