name: Load Test

on:
  issue_comment:
    types: [created]

jobs:
  loadtest:
    # Only run on PR comments with /loadtest command
    if: |
      github.event.issue.pull_request &&
      contains(github.event.comment.body, '/loadtest')
    runs-on: ubuntu-latest

    steps:
      - name: Add reaction to comment
        uses: actions/github-script@v7
        with:
          script: |
            await github.rest.reactions.createForIssueComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: context.payload.comment.id,
              content: 'rocket'
            });

      - name: Get PR details
        id: pr
        uses: actions/github-script@v7
        with:
          script: |
            const pr = await github.rest.pulls.get({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.issue.number
            });
            core.setOutput('head_ref', pr.data.head.ref);
            core.setOutput('head_sha', pr.data.head.sha);
            core.setOutput('base_ref', pr.data.base.ref);
            core.setOutput('base_sha', pr.data.base.sha);
            console.log(`PR #${context.issue.number}: ${pr.data.head.ref} -> ${pr.data.base.ref}`);

      - name: Set up Go
        uses: actions/setup-go@v5
        with:
          go-version: '1.23'
          cache: false

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Install kind
        run: |
          curl -Lo ./kind https://kind.sigs.k8s.io/dl/v0.20.0/kind-linux-amd64
          chmod +x ./kind
          sudo mv ./kind /usr/local/bin/kind

      # Build OLD image from base branch (e.g., main)
      - name: Checkout base branch (old)
        uses: actions/checkout@v4
        with:
          ref: ${{ steps.pr.outputs.base_ref }}
          path: old

      - name: Build old image
        run: |
          cd old
          docker build -t localhost/reloader:old -f Dockerfile .
          echo "Built old image from ${{ steps.pr.outputs.base_ref }} (${{ steps.pr.outputs.base_sha }})"

      # Build NEW image from PR branch
      - name: Checkout PR branch (new)
        uses: actions/checkout@v4
        with:
          ref: ${{ steps.pr.outputs.head_ref }}
          path: new

      - name: Build new image
        run: |
          cd new
          docker build -t localhost/reloader:new -f Dockerfile .
          echo "Built new image from ${{ steps.pr.outputs.head_ref }} (${{ steps.pr.outputs.head_sha }})"

      # Build and run loadtest from PR branch
      - name: Build loadtest tool
        run: |
          cd new/test/loadtest
          go build -o loadtest ./cmd/loadtest

      - name: Run A/B comparison load test
        id: loadtest
        run: |
          cd new/test/loadtest
          ./loadtest run \
            --old-image=localhost/reloader:old \
            --new-image=localhost/reloader:new \
            --scenario=all \
            --duration=60 2>&1 | tee loadtest-output.txt
          echo "exitcode=${PIPESTATUS[0]}" >> $GITHUB_OUTPUT

      - name: Upload results
        uses: actions/upload-artifact@v4
        if: always()
        with:
          name: loadtest-results
          path: |
            new/test/loadtest/results/
            new/test/loadtest/loadtest-output.txt
          retention-days: 30

      - name: Post results comment
        uses: actions/github-script@v7
        if: always()
        with:
          script: |
            const fs = require('fs');

            let results = '';
            const resultsDir = 'new/test/loadtest/results';

            // Collect summary of all scenarios
            let passCount = 0;
            let failCount = 0;
            const summaries = [];

            if (fs.existsSync(resultsDir)) {
              const scenarios = fs.readdirSync(resultsDir).sort();
              for (const scenario of scenarios) {
                const reportPath = `${resultsDir}/${scenario}/report.txt`;
                if (fs.existsSync(reportPath)) {
                  const report = fs.readFileSync(reportPath, 'utf8');

                  // Extract status from report
                  const statusMatch = report.match(/Status:\s+(PASS|FAIL)/);
                  const status = statusMatch ? statusMatch[1] : 'UNKNOWN';

                  if (status === 'PASS') passCount++;
                  else failCount++;

                  // Extract key metrics for summary
                  const actionMatch = report.match(/action_total\s+[\d.]+\s+[\d.]+\s+[\d.]+/);
                  const errorsMatch = report.match(/errors_total\s+[\d.]+\s+[\d.]+/);

                  summaries.push(`| ${scenario} | ${status === 'PASS' ? '✅' : '❌'} ${status} |`);

                  results += `\n<details>\n<summary>${status === 'PASS' ? '✅' : '❌'} ${scenario}</summary>\n\n\`\`\`\n${report}\n\`\`\`\n</details>\n`;
                }
              }
            }

            if (!results) {
              // Read raw output if no reports
              if (fs.existsSync('new/test/loadtest/loadtest-output.txt')) {
                const output = fs.readFileSync('new/test/loadtest/loadtest-output.txt', 'utf8');
                const maxLen = 60000;
                results = output.length > maxLen
                  ? output.substring(output.length - maxLen)
                  : output;
                results = `\`\`\`\n${results}\n\`\`\``;
              } else {
                results = 'No results available';
              }
            }

            const overallStatus = failCount === 0 ? '✅ ALL PASSED' : `❌ ${failCount} FAILED`;

            const body = `## Load Test Results ${overallStatus}

            **Comparing:** \`${{ steps.pr.outputs.base_ref }}\` (old) vs \`${{ steps.pr.outputs.head_ref }}\` (new)
            **Old commit:** ${{ steps.pr.outputs.base_sha }}
            **New commit:** ${{ steps.pr.outputs.head_sha }}
            **Triggered by:** @${{ github.event.comment.user.login }}

            ### Summary

            | Scenario | Status |
            |----------|--------|
            ${summaries.join('\n')}

            **Total:** ${passCount} passed, ${failCount} failed

            ### Detailed Results

            ${results}

            <details>
            <summary>📦 Download full results</summary>

            Artifacts are available in the [workflow run](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}).
            </details>
            `;

            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              body: body
            });

      - name: Add success reaction
        if: success()
        uses: actions/github-script@v7
        with:
          script: |
            await github.rest.reactions.createForIssueComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: context.payload.comment.id,
              content: '+1'
            });

      - name: Add failure reaction
        if: failure()
        uses: actions/github-script@v7
        with:
          script: |
            await github.rest.reactions.createForIssueComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: context.payload.comment.id,
              content: '-1'
            });