#!/usr/bin/env node
// ═══════════════════════════════════════════════════════════════════════════
// SIL Webhook Server — Event-driven PR-analys (ersätter cron-pollning)
// Erik-krav: "Om Git-plattformen kan skicka webhooks... är det bättre att
//             trigga analysen direkt på dessa händelser"
// ═══════════════════════════════════════════════════════════════════════════

import { createServer } from 'http';
import { execSync, spawn } from 'child_process';
import { readFileSync, writeFileSync, appendFileSync } from 'fs';
import { createHmac } from 'crypto';

const PORT = process.env.SIL_WEBHOOK_PORT || 8765;
const SECRET = process.env.SIL_WEBHOOK_SECRET || ''; // Set this!
const LOG_PATH = '/home/bernt/.openclaw/workspace/SIL/webhook-events.jsonl';

// ── Webhook Handler ───────────────────────────────────────────────────────

class WebhookServer {
  constructor() {
    this.pendingAnalyses = new Map();
  }

  verifySignature(payload, signature) {
    if (!SECRET) {
      console.warn('⚠️  Ingen WEBHOOK_SECRET satt — accepterar alla requests');
      return true;
    }

    const hmac = createHmac('sha256', SECRET);
    hmac.update(payload);
    const expected = `sha256=${hmac.digest('hex')}`;
    return signature === expected;
  }

  handleGitHubWebhook(req, body) {
    const event = req.headers['x-github-event'];
    const delivery = req.headers['x-github-delivery'];

    console.log(`📥 GitHub event: ${event} (delivery: ${delivery})`);

    const payload = JSON.parse(body);

    switch (event) {
      case 'pull_request':
        return this.handlePullRequest(payload);
      case 'push':
        return this.handlePush(payload);
      case 'pull_request_review':
        return this.handlePRReview(payload);
      default:
        return { status: 'ignored', reason: `Event ${event} hanteras inte` };
    }
  }

  handleGitLabWebhook(req, body) {
    const event = req.headers['x-gitlab-event'];
    console.log(`📥 GitLab event: ${event}`);

    const payload = JSON.parse(body);

    switch (event) {
      case 'Merge Request Hook':
        return this.handleMergeRequest(payload);
      case 'Push Hook':
        return this.handleGitLabPush(payload);
      default:
        return { status: 'ignored', reason: `Event ${event} hanteras inte` };
    }
  }

  handlePullRequest(payload) {
    const action = payload.action;
    const pr = payload.pull_request;

    if (!pr) return { status: 'error', reason: 'Ingen PR-data' };

    // Vi bryr oss om: opened, synchronize (nya commits), reopened
    if (!['opened', 'synchronize', 'reopened'].includes(action)) {
      return { status: 'ignored', reason: `Action ${action} triggar inte analys` };
    }

    const analysis = {
      id: `pr-${pr.number}-${Date.now()}`,
      type: 'github_pr',
      prNumber: pr.number,
      title: pr.title,
      branch: pr.head.ref,
      base: pr.base.ref,
      repo: payload.repository?.full_name || 'unknown',
      action,
      author: pr.user?.login,
      url: pr.html_url,
      timestamp: new Date().toISOString()
    };

    this.queueAnalysis(analysis);
    return { status: 'queued', analysisId: analysis.id };
  }

  handleMergeRequest(payload) {
    const mr = payload.object_attributes;

    if (!mr) return { status: 'error', reason: 'Ingen MR-data' };

    const analysis = {
      id: `mr-${mr.iid}-${Date.now()}`,
      type: 'gitlab_mr',
      mrNumber: mr.iid,
      title: mr.title,
      branch: mr.source_branch,
      base: mr.target_branch,
      repo: payload.project?.path_with_namespace || 'unknown',
      action: mr.action,
      author: mr.author_id,
      url: mr.url,
      timestamp: new Date().toISOString()
    };

    this.queueAnalysis(analysis);
    return { status: 'queued', analysisId: analysis.id };
  }

  handlePush(payload) {
    const ref = payload.ref;

    // Bara intresserad av branch pushes (inte tags)
    if (!ref.startsWith('refs/heads/')) {
      return { status: 'ignored', reason: 'Inte en branch-push' };
    }

    const branch = ref.replace('refs/heads/', '');

    // Om det finns en öppen PR för denna branch, analysera den
    const analysis = {
      id: `push-${branch}-${Date.now()}`,
      type: 'push',
      branch,
      repo: payload.repository?.full_name || 'unknown',
      commits: payload.commits?.length || 0,
      timestamp: new Date().toISOString()
    };

    this.queueAnalysis(analysis);
    return { status: 'queued', analysisId: analysis.id };
  }

  handleGitLabPush(payload) {
    const ref = payload.ref;
    if (!ref.startsWith('refs/heads/')) {
      return { status: 'ignored', reason: 'Inte en branch-push' };
    }

    const branch = ref.replace('refs/heads/', '');

    const analysis = {
      id: `push-${branch}-${Date.now()}`,
      type: 'gitlab_push',
      branch,
      repo: payload.project?.path_with_namespace || 'unknown',
      commits: payload.commits?.length || 0,
      timestamp: new Date().toISOString()
    };

    this.queueAnalysis(analysis);
    return { status: 'queued', analysisId: analysis.id };
  }

  handlePRReview(payload) {
    // När en review submit:as, kör analys igen (kan ha ändrats)
    const pr = payload.pull_request;

    const analysis = {
      id: `review-${pr.number}-${Date.now()}`,
      type: 'pr_review',
      prNumber: pr.number,
      title: pr.title,
      branch: pr.head.ref,
      base: pr.base.ref,
      state: payload.review?.state,
      timestamp: new Date().toISOString()
    };

    this.queueAnalysis(analysis);
    return { status: 'queued', analysisId: analysis.id };
  }

  // ── Analysis Queue ──────────────────────────────────────────────────────

  queueAnalysis(analysis) {
    this.pendingAnalyses.set(analysis.id, analysis);

    // Logga event
    appendFileSync(LOG_PATH, JSON.stringify({
      ...analysis,
      status: 'queued'
    }) + '\n', 'utf8');

    console.log(`🔄 Köad analys: ${analysis.id}`);
    console.log(`   PR/MR: ${analysis.title || analysis.branch}`);
    console.log(`   Branch: ${analysis.branch} → ${analysis.base}`);

    // Kör analys asynkront
    this.runAnalysis(analysis).then(result => {
      console.log(`✅ Analys klar: ${analysis.id}`);
      this.pendingAnalyses.delete(analysis.id);
    }).catch(err => {
      console.error(`❌ Analys fel: ${analysis.id}`, err.message);
      this.pendingAnalyses.delete(analysis.id);
    });
  }

  async runAnalysis(analysis) {
    const repoPath = '/home/bernt/repos/quixzoom.com'; // Konfigurerbart

    // Kör pr-analyzer
    return new Promise((resolve, reject) => {
      const child = spawn('node', [
        '/home/bernt/.openclaw/workspace/SIL/pr-analyzer.mjs',
        repoPath,
        analysis.base || 'main',
        analysis.branch || 'HEAD'
      ], {
        cwd: repoPath,
        stdio: 'pipe'
      });

      let output = '';
      child.stdout.on('data', data => { output += data; });
      child.stderr.on('data', data => { console.error(data.toString()); });

      child.on('close', code => {
        // Logga resultat
        appendFileSync(LOG_PATH, JSON.stringify({
          ...analysis,
          status: 'completed',
          exitCode: code,
          completedAt: new Date().toISOString()
        }) + '\n', 'utf8');

        if (code === 0) {
          resolve(output);
        } else {
          reject(new Error(`Exit code ${code}`));
        }
      });
    });
  }

  // ── HTTP Server ─────────────────────────────────────────────────────────

  start() {
    const server = createServer((req, res) => {
      // Endast POST
      if (req.method !== 'POST') {
        res.writeHead(405);
        res.end('Method not allowed');
        return;
      }

      let body = '';
      req.on('data', chunk => { body += chunk; });
      req.on('end', () => {
        try {
          // Verifiera signatur om konfigurerat
          const signature = req.headers['x-hub-signature-256'] || req.headers['x-gitlab-token'];
          if (!this.verifySignature(body, signature)) {
            res.writeHead(401);
            res.end('Unauthorized');
            return;
          }

          // Route till rätt handler
          let result;
          if (req.headers['x-github-event']) {
            result = this.handleGitHubWebhook(req, body);
          } else if (req.headers['x-gitlab-event']) {
            result = this.handleGitLabWebhook(req, body);
          } else {
            result = { status: 'error', reason: 'Okänd git-plattform' };
          }

          res.writeHead(200, { 'Content-Type': 'application/json' });
          res.end(JSON.stringify(result));
        } catch (e) {
          console.error('Webhook-fel:', e);
          res.writeHead(500);
          res.end(JSON.stringify({ status: 'error', message: e.message }));
        }
      });
    });

    server.listen(PORT, () => {
      console.log('═══════════════════════════════════════════════════════════════');
      console.log('           SIL WEBHOOK SERVER');
      console.log('           (Event-driven PR-analys)');
      console.log('═══════════════════════════════════════════════════════════════\n');
      console.log(`🌐 Lyssnar på port ${PORT}`);
      console.log(`📁 Event-log: ${LOG_PATH}`);
      console.log(`\nGitHub webhook URL: http://<server>:${PORT}/github`);
      console.log(`GitLab webhook URL: http://<server>:${PORT}/gitlab`);
      console.log(`\n⚙️  Konfigurera i din Git-plattform:`);
      console.log('   - Content type: application/json');
      console.log('   - Events: Pull requests, Pushes');
      if (!SECRET) {
        console.log('\n⚠️  VARNING: Sätt SIL_WEBHOOK_SECRET för säkerhet');
      }
      console.log('\nTryck Ctrl+C för att avsluta\n');
    });

    return server;
  }
}

// ── Main ──────────────────────────────────────────────────────────────────

const server = new WebhookServer();
server.start();