quality-checks.yml

name: 💎 Code Quality Checks

on:
  pull_request_target:
    branches: [ main ]
    types: [opened, synchronize, reopened]

permissions:
  contents: read
  pull-requests: write
  issues: write

jobs:
  quality-validation:
    name: 📋 Validate Code Quality
    runs-on: ubuntu-latest

    steps:
    - name: 📥 Checkout PR code
      uses: actions/checkout@v4
      with:
        ref: ${{ github.event.pull_request.head.sha }}

    - name: 🔍 Get changed files
      id: changed-files
      uses: tj-actions/changed-files@v40
      with:
        files: |
          **/*.c
          **/*.cpp
          **/*.java
          **/*.py
          **/*.js
          **/*.go
          **/*.rs

    - name: 📊 Check code quality standards
      if: steps.changed-files.outputs.any_changed == 'true'
      id: quality-check
      run: |
        echo "Checking code quality for changed files..."

        changed_files="${{ steps.changed-files.outputs.all_changed_files }}"
        file_count=$(echo "$changed_files" | wc -w)

        echo "Number of changed files: $file_count"

        missing_complexity=()
        missing_comments=()
        missing_tests=()
        missing_description=()
        quality_issues=""

        # Be more lenient for single file contributions
        is_single_file=false
        if [ "$file_count" -eq 1 ]; then
          is_single_file=true
          echo "Single file contribution detected - applying relaxed checks"
        fi

        for file in $changed_files; do
          if [ ! -f "$file" ]; then
            continue
          fi

          echo "Checking: $file"
          filename=$(basename "$file")
          has_issues=false

          # Check for complexity analysis (Time/Space complexity)
          if ! grep -qi "complexity\|time.*complexity\|space.*complexity\|O(.*)" "$file"; then
            missing_complexity+=("$file")
            has_issues=true
          fi

          # Check for meaningful comments (more lenient for single file)
          min_comments=5
          if [ "$is_single_file" = true ]; then
            min_comments=3
          fi

          comment_count=$(grep -cE "^\s*(//|#|\*|/\*)" "$file" 2>/dev/null || echo "0")
          if [ "$comment_count" -lt "$min_comments" ]; then
            missing_comments+=("$file")
            has_issues=true
          fi

          # Check for algorithm description or documentation
          if ! grep -qi "algorithm\|description\|@description\|purpose\|what.*does" "$file"; then
            missing_description+=("$file")
            has_issues=true
          fi

          # Check for test cases or examples
          if ! grep -qi "test\|example\|main\|if.*__name__\|public static void main" "$file"; then
            missing_tests+=("$file")
            has_issues=true
          fi

          # Check file size (more lenient for single file)
          min_lines=20
          if [ "$is_single_file" = true ]; then
            min_lines=15
          fi

          file_size=$(wc -l < "$file")
          if [ "$file_size" -lt "$min_lines" ]; then
            quality_issues="${quality_issues}⚠️ **$file** - File is very small ($file_size lines). Consider adding more documentation or test cases.\n"
          fi
        done

        echo "is_single_file=$is_single_file" >> $GITHUB_OUTPUT

        # Build quality report
        has_quality_issues=false
        critical_issues=0

        if [ ${#missing_complexity[@]} -gt 0 ]; then
          has_quality_issues=true
          critical_issues=$((critical_issues + 1))
          quality_issues="${quality_issues}### ❌ Missing Complexity Analysis\n\n"
          quality_issues="${quality_issues}These files don't include time/space complexity:\n"
          for f in "${missing_complexity[@]}"; do
            quality_issues="${quality_issues}- \`$f\`\n"
          done
          quality_issues="${quality_issues}\n**Required:** Add comments explaining time and space complexity (e.g., \`Time: O(n log n), Space: O(n)\`)\n\n"
        fi

        if [ ${#missing_description[@]} -gt 0 ]; then
          has_quality_issues=true
          critical_issues=$((critical_issues + 1))
          quality_issues="${quality_issues}### ❌ Missing Algorithm Description\n\n"
          quality_issues="${quality_issues}These files don't explain what the algorithm does:\n"
          for f in "${missing_description[@]}"; do
            quality_issues="${quality_issues}- \`$f\`\n"
          done
          quality_issues="${quality_issues}\n**Required:** Add a description explaining the algorithm, its purpose, and how it works\n\n"
        fi

        # Only warn about comments/tests for non-single-file PRs or if there are other critical issues
        if [ ${#missing_comments[@]} -gt 0 ] && ([ "$is_single_file" = false ] || [ "$critical_issues" -gt 0 ]); then
          has_quality_issues=true
          quality_issues="${quality_issues}### ⚠️ Insufficient Comments\n\n"
          quality_issues="${quality_issues}These files have very few comments:\n"
          for f in "${missing_comments[@]}"; do
            quality_issues="${quality_issues}- \`$f\`\n"
          done
          quality_issues="${quality_issues}\n**Recommended:** Add inline comments explaining the logic and key steps\n\n"
        fi

        if [ ${#missing_tests[@]} -gt 0 ] && ([ "$is_single_file" = false ] || [ "$critical_issues" -gt 0 ]); then
          has_quality_issues=true
          quality_issues="${quality_issues}### ⚠️ No Test Cases or Examples\n\n"
          quality_issues="${quality_issues}These files don't include test cases:\n"
          for f in "${missing_tests[@]}"; do
            quality_issues="${quality_issues}- \`$f\`\n"
          done
          quality_issues="${quality_issues}\n**Recommended:** Add example usage or test cases to demonstrate the code works\n\n"
        fi

        # Only report issues if there are critical problems OR multiple files with issues
        should_comment=false
        if [ "$critical_issues" -gt 0 ]; then
          should_comment=true
        elif [ "$is_single_file" = false ] && [ "$has_quality_issues" = true ]; then
          should_comment=true
        fi

        # Save results
        if [ "$should_comment" = true ]; then
          echo "issues_found=true" >> $GITHUB_OUTPUT
          echo "quality_report<<EOF" >> $GITHUB_OUTPUT
          echo -e "$quality_issues" >> $GITHUB_OUTPUT
          echo "EOF" >> $GITHUB_OUTPUT
        else
          echo "issues_found=false" >> $GITHUB_OUTPUT
        fi

    - name: 💬 Post quality feedback
      if: steps.quality-check.outputs.issues_found == 'true'
      uses: actions/github-script@v7
      env:
        QUALITY_REPORT: ${{ steps.quality-check.outputs.quality_report }}
      with:
        script: |
          const report = process.env.QUALITY_REPORT;

          // Check if we already commented about quality
          const comments = await github.rest.issues.listComments({
            owner: context.repo.owner,
            repo: context.repo.repo,
            issue_number: context.issue.number
          });

          const botComment = comments.data.find(comment =>
            comment.user.type === 'Bot' && comment.body.includes('💎 Code Quality Check Results')
          );

          const comment = `## 💎 Code Quality Check Results

          ${ report }

          ### 📚 Quality Standards

          To maintain high quality, every contribution should include:

          1. **✍️ Algorithm Description**
             - Explain what the algorithm does
             - Describe the approach and methodology
             - Include use cases or applications

          2. **📊 Complexity Analysis**
             - Time complexity (e.g., O(n log n))
             - Space complexity (e.g., O(n))
             - Brief explanation of why

          3. **💬 Meaningful Comments**
             - Explain complex logic
             - Document function parameters
             - Add inline comments for clarity

          4. **✅ Test Cases/Examples**
             - Demonstrate the code works
             - Show different input scenarios
             - Include edge cases

          ### 💡 Example Template

          \`\`\`python
          """
          Binary Search Algorithm

          Description: Searches for a target value in a sorted array using divide-and-conquer

          Time Complexity: O(log n) - halves search space each iteration
          Space Complexity: O(1) - only uses constant extra space
          """

          def binary_search(arr, target):
              # Initialize pointers
              left, right = 0, len(arr) - 1

              while left <= right:
                  mid = (left + right) // 2

                  # Check if target found
                  if arr[mid] == target:
                      return mid
                  # Search right half
                  elif arr[mid] < target:
                      left = mid + 1
                  # Search left half
                  else:
                      right = mid - 1

              return -1  # Not found

          # Test cases
          if __name__ == "__main__":
              test_arr = [1, 3, 5, 7, 9]
              print(binary_search(test_arr, 5))  # Output: 2
              print(binary_search(test_arr, 6))  # Output: -1
          \`\`\`

          ### 🔧 How to Fix

          1. Review each file mentioned above
          2. Add the missing documentation
          3. Push your changes
          4. The workflow will re-run automatically

          ### 💪 You've Got This!

          These checks help maintain quality and make your contribution more valuable to learners. Thank you for taking the time to improve! 🙏

          ---
          *Quality over quantity - let's build something amazing together! 🌟*`;

          // Only post if we haven't already commented, otherwise update
          if (!botComment) {
            await github.rest.issues.createComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              issue_number: context.issue.number,
              body: comment
            });
          } else {
            await github.rest.issues.updateComment({
              owner: context.repo.owner,
              repo: context.repo.repo,
              comment_id: botComment.id,
              body: comment
            });
          }

    - name: ✅ Quality check summary
      run: |
        if [ "${{ steps.quality-check.outputs.issues_found }}" = "true" ]; then
          echo "⚠️ Quality issues detected - please review the feedback"
          echo "This is not a failure - just suggestions to improve quality"
        else
          echo "✅ All quality checks passed - excellent work!"
        fi