name: 'Devin Session Checker'
description: 'Check for existing Devin sessions on a PR'

inputs:
  devin-api-key:
    description: 'Devin API key'
    required: true
  github-token:
    description: 'GitHub token for API calls'
    required: true
  pr-number:
    description: 'PR number to check for existing sessions'
    required: true

outputs:
  has-existing-session:
    description: 'Whether an existing active session was found (true/false)'
    value: ${{ steps.check-session.outputs.has-existing-session }}
  session-id:
    description: 'ID of the existing session (if found)'
    value: ${{ steps.check-session.outputs.session-id }}
  session-url:
    description: 'URL of the existing session (if found)'
    value: ${{ steps.check-session.outputs.session-url }}

runs:
  using: 'composite'
  steps:
    - name: Check for existing Devin session
      id: check-session
      uses: actions/github-script@v7
      env:
        DEVIN_API_KEY: ${{ inputs.devin-api-key }}
        PR_NUMBER: ${{ inputs.pr-number }}
      with:
        github-token: ${{ inputs.github-token }}
        script: |
          const { owner, repo } = context.repo;
          const prNumber = parseInt(process.env.PR_NUMBER, 10);
          const SESSION_URL_REGEX = /app\.devin\.ai\/sessions\/([a-f0-9-]+)/;
          const ACTIVE_STATUSES = ['working', 'blocked', 'resumed'];

          async function checkSessionStatus(sessionId) {
            const response = await fetch(`https://api.devin.ai/v1/sessions/${sessionId}`, {
              headers: {
                'Authorization': `Bearer ${process.env.DEVIN_API_KEY}`,
                'Content-Type': 'application/json'
              }
            });

            if (!response.ok) {
              console.log(`Failed to fetch session ${sessionId}: ${response.status}`);
              return null;
            }

            return await response.json();
          }

          const { data: pr } = await github.rest.pulls.get({
            owner,
            repo,
            pull_number: prNumber
          });

          const prBody = pr.body || '';
          const prSessionMatch = prBody.match(SESSION_URL_REGEX);

          if (prSessionMatch) {
            const sessionId = prSessionMatch[1];
            console.log(`PR was created by Devin session: ${sessionId}`);
            const session = await checkSessionStatus(sessionId);
            if (session) {
              console.log(`PR creator session status: ${session.status_enum}`);
              if (ACTIVE_STATUSES.includes(session.status_enum)) {
                core.setOutput('has-existing-session', 'true');
                core.setOutput('session-id', sessionId);
                core.setOutput('session-url', `https://app.devin.ai/sessions/${sessionId}`);
                return;
              } else {
                console.log(`PR creator session ${sessionId} is not active, will check comments`);
              }
            }
          }

          const devinSessionPatterns = [
            'Devin AI is completing this stale PR',
            'Devin AI is addressing Cubic AI',
            'Devin AI is resolving merge conflicts'
          ];

          const comments = await github.rest.issues.listComments({
            owner,
            repo,
            issue_number: prNumber
          });

          for (const comment of comments.data.reverse()) {
            const hasDevinSession = devinSessionPatterns.some(pattern => comment.body?.includes(pattern));
            if (hasDevinSession) {
              const match = comment.body?.match(SESSION_URL_REGEX);
              if (match) {
                const sessionId = match[1];
                console.log(`Found existing Devin session from comment: ${sessionId}`);

                  const session = await checkSessionStatus(sessionId);
                  if (session) {
                    if (ACTIVE_STATUSES.includes(session.status_enum)) {
                    console.log(`Session ${sessionId} is active (status: ${session.status_enum})`);
                    core.setOutput('has-existing-session', 'true');
                    core.setOutput('session-id', sessionId);
                    core.setOutput('session-url', `https://app.devin.ai/sessions/${sessionId}`);
                    return;
                  } else {
                    console.log(`Session ${sessionId} is not active (status: ${session.status_enum})`);
                  }
                }
              }
            }
          }

          console.log('No existing active Devin session found');
          core.setOutput('has-existing-session', 'false');
          core.setOutput('session-id', '');
          core.setOutput('session-url', '');