name: Line Length Check

on:
  pull_request:
    branches: [ '*' ]

# Cancel superseded in-progress runs for the same PR.
concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: ${{ github.event_name == 'pull_request' }}

jobs:
  line-length-check:
    runs-on: ubuntu-latest
    name: Check 80 character line limit

    steps:
    - name: Checkout code
      uses: actions/checkout@v4
      with:
        fetch-depth: 0

    - name: Check line length in PR changes
      run: |
        # Get the base branch (usually main/master)
        BASE_BRANCH="${{ github.event.pull_request.base.ref }}"

        echo "Checking line length (max 80 characters) for changed files in " \
          "src/, examples/, and jni/ directories..."
        echo "================================================================"

        # Create temporary files with unique names
        changed_files=$(mktemp)
        violations_file=$(mktemp)

        # Get all changed files in this PR and filter for target directories
        git diff --name-only "origin/$BASE_BRANCH"...HEAD | \
          grep -E '^(src/|examples/|jni/)' > "$changed_files" || true

        # Initialize violation count
        violation_count=0

        # Check each changed file
        while IFS= read -r file; do
          if [[ -f "$file" ]]; then
            # Skip WolfCryptProvider.java as it contains service mappings
            # that legitimately exceed 80 characters
            if [[ "$file" == "src/main/java/com/wolfssl/provider/jce/WolfCryptProvider.java" ]]; then
              echo "Skipping $file (contains security service mappings)"
              continue
            fi

            # Skip auto-generated JNI header files in jni/include/
            # These are generated by javac -h and contain long function
            # signatures that cannot be controlled
            if [[ "$file" =~ ^jni/include/.*\.h$ ]]; then
              echo "Skipping $file (auto-generated JNI header)"
              continue
            fi

            # Skip shell scripts in examples/ directory
            # These often contain long command lines that are better kept on
            # single lines for readability
            if [[ "$file" =~ ^examples/.*\.sh$ ]]; then
              echo "Skipping $file (shell script in examples)"
              continue
            fi

            # Skip certificate/key files. These carry encoded key material
            # and OpenSSL text dumps (long Issuer/Subject lines) that cannot
            # be wrapped. Skip the whole certs tree since some files there
            # (CRLs and similar) do not use a .pem or .der extension.
            if [[ "$file" =~ ^examples/certs/ ]] || \
               [[ "$file" =~ \.(pem|der)$ ]]; then
              echo "Skipping $file (certificate/key file)"
              continue
            fi

            echo "Checking: $file"

            # Get added lines with actual file line numbers and check their length
            new_line_num=0
            git diff "origin/$BASE_BRANCH"...HEAD "$file" | \
              while IFS= read -r line; do
                # Track line numbers from diff headers - format: @@ -old_start,old_count +new_start,new_count @@
                if [[ "$line" =~ ^@@.*\+([0-9]+) ]]; then
                  # Extract starting line number for new file (after +)
                  # Subtract 1 because we'll increment before processing first line
                  new_line_num=$((${BASH_REMATCH[1]} - 1))
                elif [[ "$line" =~ ^(\+[^+].*) ]]; then
                  # This is an added line (not a +++ header)
                  # Increment line number BEFORE processing (since this line exists in new file)
                  new_line_num=$((new_line_num + 1))
                  added_line="${line:1}"  # Remove leading +
                  char_count=${#added_line}

                  # Skip JNI method signatures and calls to avoid false positives
                  # These are auto-generated names that can't be shortened
                  if [[ $char_count -gt 80 ]]; then
                    # Check if this is a JNI method signature, call, or parameter line that should be ignored
                    if [[ "$added_line" =~ JNIEXPORT.*JNICALL.*Java_com_wolfssl_ ]] || \
                       [[ "$added_line" =~ Java_com_wolfssl_.*\( ]] || \
                       [[ "$added_line" =~ ^[[:space:]]*return[[:space:]]+Java_com_wolfssl_.* ]] || \
                       [[ "$added_line" =~ ^[[:space:]]*\(JNIEnv\*[[:space:]]+env.*\) ]] || \
                       [[ "$added_line" =~ ^[[:space:]]*JNIEnv\*[[:space:]]+env.* ]]; then
                      echo "$file:$new_line_num - Skipping JNI method signature/call/parameters ($char_count characters)"
                      echo "   Line: $added_line"
                    else
                      echo "❌ $file:$new_line_num - Line too long ($char_count characters)"
                      echo "   Line: $added_line"
                      echo "violation" >> "$violations_file"
                    fi
                  fi
                elif [[ "$line" =~ ^[[:space:]] ]]; then
                  # Context line (unchanged) - increment new file line number
                  new_line_num=$((new_line_num + 1))
                # Removed lines (starting with -) don't affect new file line numbers
                fi
              done
          fi
        done < "$changed_files"

        # Count violations
        if [[ -f "$violations_file" ]]; then
          violation_count=$(grep -c "violation" "$violations_file" || echo 0)
        else
          violation_count=0
        fi

        echo "================================================================"

        if [[ $violation_count -gt 0 ]]; then
          echo "❌ Found $violation_count line(s) exceeding 80 " \
            "characters in PR changes"
          echo ""
          echo "Please ensure all lines are 80 characters or less " \
            "as per coding standards."
          echo "You can check line length in your editor or use this command:"
          echo "  grep -n '.\{81,\}' <filename>"
          rm -f "$violations_file" "$changed_files"
          exit 1
        else
          echo "✅ All changed lines are within the 80 character limit"
          rm -f "$violations_file" "$changed_files"
          exit 0
        fi