name: KB Lint

on:
  push:
    paths:
      - 'kb/**/*.md'
  pull_request:
    paths:
      - 'kb/**/*.md'

permissions:
  contents: read

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      
      - name: Validate KB Files
        run: |
          set -e
          
          # Colors for output
          RED='\033[0;31m'
          GREEN='\033[0;32m'
          YELLOW='\033[1;33m'
          NC='\033[0m' # No Color
          
          echo "Validating KB files..."
          
          # Find all KB files that changed
          if [ "${{ github.event_name }}" = "pull_request" ]; then
            # For pull requests, check changed files
            changed_files=$(git diff --name-only --diff-filter=ACMR origin/${{ github.base_ref }}...HEAD -- 'kb/**/*.md' || true)
          else
            # For push, check all KB files
            changed_files=$(git diff --name-only --diff-filter=ACMR HEAD~1...HEAD -- 'kb/**/*.md' || find kb -type f -name "*.md" 2>/dev/null || true)
          fi
          
          if [ -z "$changed_files" ]; then
            echo "No KB files changed, skipping validation"
            exit 0
          fi
          
          errors=0
          
          # Process each changed file
          while IFS= read -r file; do
            # Skip empty lines
            [ -z "$file" ] && continue
            
            # Skip if file doesn't exist (deleted files)
            [ ! -f "$file" ] && continue
            
            # Skip special directories and files
            if [[ "$file" == *"/_guides/"* ]] || \
               [[ "$file" == *"/_templates/"* ]] || \
               [[ "$file" == "kb/README.md" ]] || \
               [[ "$file" == "kb/_index.md" ]] || \
               [[ "$file" == "kb/CHANGELOG.md" ]]; then
              echo -e "${YELLOW}⏭️  Skipping: $file (excluded from validation)${NC}"
              continue
            fi
            
            filename=$(basename "$file")
            relative_path="${file#kb/}"
            file_errors=0
            
            echo -e "\n${GREEN}Validating: $file${NC}"
            
            # Validate filename pattern
            if ! [[ "$filename" =~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}--[a-z0-9-]+--(idea|note|spec|decision|howto|retro|meeting)(--p[0-9]+)?\.md$ ]]; then
              echo -e "${RED}❌ ERROR: Invalid filename pattern${NC}"
              echo "   Expected: YYYY-MM-DD--slug--type.md"
              echo "   Got: $filename"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Extract date and type from filename
            filename_date=$(echo "$filename" | sed -E 's/^([0-9]{4}-[0-9]{2}-[0-9]{2})--.*/\1/')
            filename_type=$(echo "$filename" | sed -E 's/.*--([a-z]+)(--p[0-9]+)?\.md$/\1/')
            
            # Check frontmatter exists
            if ! grep -q "^---$" "$file"; then
              echo -e "${RED}❌ ERROR: Missing frontmatter delimiter${NC}"
              echo "   File must start with '---'"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Extract frontmatter
            frontmatter=$(sed -n '/^---$/,/^---$/p' "$file" | sed '1d;$d')
            
            if [ -z "$frontmatter" ]; then
              echo -e "${RED}❌ ERROR: Empty frontmatter${NC}"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Check required fields (14 base fields)
            REQUIRED_FIELDS=("title" "date" "author" "source" "project" "topics" "tags" "type" "status" "routing_hint" "proposed_path" "routing_confidence" "related" "summary")
            for field in "${REQUIRED_FIELDS[@]}"; do
              if ! echo "$frontmatter" | grep -q "^${field}:"; then
                echo -e "${RED}❌ ERROR: Missing required field: $field${NC}"
                file_errors=$((file_errors + 1))
                errors=$((errors + 1))
              fi
            done
            
            # Validate date matches
            frontmatter_date=$(echo "$frontmatter" | grep "^date:" | sed -E 's/^date:[[:space:]]*["'\'']?([^"'\'']+)["'\'']?.*/\1/' | tr -d ' ' | head -1)
            if [ "$frontmatter_date" != "$filename_date" ]; then
              echo -e "${RED}❌ ERROR: Date mismatch${NC}"
              echo "   Filename date: $filename_date"
              echo "   Frontmatter date: $frontmatter_date"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Validate type matches
            frontmatter_type=$(echo "$frontmatter" | grep "^type:" | sed -E 's/^type:[[:space:]]*["'\'']?([^"'\'']+)["'\'']?.*/\1/' | tr -d ' ' | head -1)
            if [ "$frontmatter_type" != "$filename_type" ]; then
              echo -e "${RED}❌ ERROR: Type mismatch${NC}"
              echo "   Filename type: $filename_type"
              echo "   Frontmatter type: $frontmatter_type"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Validate routing_confidence
            routing_confidence=$(echo "$frontmatter" | grep "^routing_confidence:" | sed -E 's/^routing_confidence:[[:space:]]*([0-9.]+).*/\1/' | tr -d ' ' | head -1)
            if ! awk -v conf="$routing_confidence" 'BEGIN {if (conf < 0.0 || conf > 1.0 || conf == "") exit 1}' 2>/dev/null; then
              echo -e "${RED}❌ ERROR: Invalid routing_confidence value${NC}"
              echo "   Value: $routing_confidence"
              echo "   Must be numeric between 0.00 and 1.00"
              file_errors=$((file_errors + 1))
              errors=$((errors + 1))
            fi
            
            # Enforce review queue policy
            if awk -v conf="$routing_confidence" 'BEGIN {exit !(conf < 0.60)}' 2>/dev/null; then
              if [[ "$file" != *"/_review_queue/"* ]]; then
                echo -e "${RED}❌ ERROR: File has routing_confidence < 0.60 but is not in kb/_review_queue/${NC}"
                echo "   routing_confidence: $routing_confidence"
                echo "   File path: $file"
                file_errors=$((file_errors + 1))
                errors=$((errors + 1))
              fi
            fi
            
            if [ $file_errors -eq 0 ]; then
              echo -e "${GREEN}✅ Valid: $file${NC}"
            fi
          done <<< "$changed_files"
          
          if [ $errors -gt 0 ]; then
            echo -e "\n${RED}Validation failed with $errors error(s)${NC}"
            exit 1
          else
            echo -e "\n${GREEN}All KB files validated successfully${NC}"
            exit 0
          fi