decimal-bytes 0.4.2

name: Benchmarks

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

permissions:
  contents: write
  pull-requests: write

env:
  CARGO_TERM_COLOR: always

jobs:
  # Run and compare benchmarks on push to main (compare with previous commit)
  benchmark-main:
    name: Benchmark (main)
    runs-on: ubuntu-latest
    if: github.event_name == 'push'
    steps:
      - uses: actions/checkout@v6
        with:
          fetch-depth: 2  # Need previous commit

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@stable

      - name: Install critcmp
        run: cargo install critcmp

      - name: Cache cargo registry and build
        uses: actions/cache@v5
        with:
          path: |
            ~/.cargo/registry
            ~/.cargo/git
            target
          key: ${{ runner.os }}-cargo-bench-${{ hashFiles('**/Cargo.lock', '**/Cargo.toml') }}
          restore-keys: |
            ${{ runner.os }}-cargo-bench-

      - name: Run benchmarks on current commit
        run: cargo bench --bench benchmarks -- --noplot --save-baseline current

      - name: Checkout previous commit
        run: git checkout HEAD~1

      - name: Run benchmarks on previous commit
        run: cargo bench --bench benchmarks -- --noplot --save-baseline previous

      - name: Compare benchmarks
        run: |
          echo "## Benchmark Comparison (vs previous commit)" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo "Comparing \`${{ github.sha }}\` against previous commit" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY
          critcmp previous current >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY

      - name: Upload benchmark results
        uses: actions/upload-artifact@v6
        with:
          name: benchmark-results-${{ github.sha }}
          path: target/criterion
          retention-days: 30

  # Run and compare benchmarks on PRs (compare with base branch)
  benchmark-pr:
    name: Benchmark (PR)
    runs-on: ubuntu-latest
    if: github.event_name == 'pull_request'
    steps:
      - uses: actions/checkout@v6
        with:
          fetch-depth: 0

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@stable

      - name: Install critcmp
        run: cargo install critcmp

      - name: Cache cargo registry and build
        uses: actions/cache@v5
        with:
          path: |
            ~/.cargo/registry
            ~/.cargo/git
            target
          key: ${{ runner.os }}-cargo-bench-${{ hashFiles('**/Cargo.lock', '**/Cargo.toml') }}
          restore-keys: |
            ${{ runner.os }}-cargo-bench-

      - name: Run benchmarks on PR branch
        run: cargo bench --bench benchmarks -- --noplot --save-baseline pr

      - name: Checkout base branch
        run: git checkout ${{ github.base_ref }}

      - name: Run benchmarks on base branch
        run: cargo bench --bench benchmarks -- --noplot --save-baseline base

      - name: Compare benchmarks
        run: |
          echo "## Benchmark Comparison (PR vs ${{ github.base_ref }})" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY
          critcmp base pr >> $GITHUB_STEP_SUMMARY
          echo '```' >> $GITHUB_STEP_SUMMARY

      - name: Comment on PR
        uses: actions/github-script@v8
        with:
          script: |
            const { execSync } = require('child_process');
            
            const output = execSync('critcmp base pr', { encoding: 'utf-8' });
            
            const body = `## 📊 Benchmark Comparison
            
            <details>
            <summary>Click to expand benchmark results</summary>
            
            \`\`\`
            ${output}
            \`\`\`
            
            </details>
            
            > Compared against \`${{ github.base_ref }}\` branch
            `;
            
            // Find existing comment
            const { data: comments } = await github.rest.issues.listComments({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
            });
            
            const botComment = comments.find(c => 
              c.user.type === 'Bot' && c.body.includes('Benchmark Comparison')
            );
            
            if (botComment) {
              await github.rest.issues.updateComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                comment_id: botComment.id,
                body: body
              });
            } else {
              await github.rest.issues.createComment({
                owner: context.repo.owner,
                repo: context.repo.repo,
                issue_number: context.issue.number,
                body: body
              });
            }