name: Generate Changelog

on:
  workflow_call:
    inputs:
      version:
        description: "Version for the changelog"
        required: true
        type: string
      release_type:
        description: "Release type: alpha, beta, or stable"
        required: true
        type: string
    outputs:
      changelog:
        description: "Generated changelog content"
        value: ${{ jobs.generate.outputs.changelog }}
      changelog_file:
        description: "Path to changelog file"
        value: ${{ jobs.generate.outputs.changelog_file }}

jobs:
  generate:
    name: Generate Changelog
    runs-on: ubuntu-latest
    outputs:
      changelog: ${{ steps.generate.outputs.changelog }}
      changelog_file: ${{ steps.generate.outputs.changelog_file }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Generate changelog
        id: generate
        run: |
          VERSION="${{ inputs.version }}"
          RELEASE_TYPE="${{ inputs.release_type }}"
          DATE=$(date +%Y-%m-%d)

          # Start building changelog
          CHANGELOG="## v${VERSION} (${DATE})\n\n"

          # Initialize sections
          FEATURES=""
          FIXES=""
          DOCS=""
          CHORES=""
          OTHER=""

          # Get commits since last tag
          LATEST_TAG=$(git describe --tags --abbrev=0 2>/dev/null || echo "")

          if [ -n "$LATEST_TAG" ]; then
            COMMITS=$(git log ${LATEST_TAG}..HEAD --oneline --format="%s")
          else
            COMMITS=$(git log --oneline --format="%s" | head -50)
          fi

          # Categorize commits by conventional commit type
          while IFS= read -r commit; do
            if [ -z "$commit" ]; then
              continue
            fi
            
            # Extract type from conventional commit
            if [[ "$commit" =~ ^feat(\(.+\))?:\ (.+)$ ]]; then
              FEATURES="${FEATURES}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^fix(\(.+\))?:\ (.+)$ ]]; then
              FIXES="${FIXES}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^docs(\(.+\))?:\ (.+)$ ]]; then
              DOCS="${DOCS}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^chore(\(.+\))?:\ (.+)$ ]]; then
              CHORES="${CHORES}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^refactor(\(.+\))?:\ (.+)$ ]]; then
              CHORES="${CHORES}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^test(\(.+\))?:\ (.+)$ ]]; then
              CHORES="${CHORES}- ${BASH_REMATCH[2]}\n"
            elif [[ "$commit" =~ ^ci(\(.+\))?:\ (.+)$ ]]; then
              CHORES="${CHORES}- ${BASH_REMATCH[2]}\n"
            else
              # Non-conventional commit, add to other
              OTHER="${OTHER}- ${commit}\n"
            fi
          done <<< "$COMMITS"

          # Build final changelog
          if [ -n "$FEATURES" ]; then
            CHANGELOG="${CHANGELOG}### ✨ Features\n\n${FEATURES}\n"
          fi

          if [ -n "$FIXES" ]; then
            CHANGELOG="${CHANGELOG}### 🐛 Bug Fixes\n\n${FIXES}\n"
          fi

          if [ -n "$DOCS" ]; then
            CHANGELOG="${CHANGELOG}### 📚 Documentation\n\n${DOCS}\n"
          fi

          if [ -n "$CHORES" ]; then
            CHANGELOG="${CHANGELOG}### 🔧 Maintenance\n\n${CHORES}\n"
          fi

          if [ -n "$OTHER" ]; then
            CHANGELOG="${CHANGELOG}### Other Changes\n\n${OTHER}\n"
          fi

          # If no categorized commits, add a simple message
          if [ -z "$FEATURES" ] && [ -z "$FIXES" ] && [ -z "$DOCS" ] && [ -z "$CHORES" ] && [ -z "$OTHER" ]; then
            CHANGELOG="${CHANGELOG}No notable changes in this release.\n"
          fi

          # Add release metadata
          CHANGELOG="${CHANGELOG}\n---\n\n"
          CHANGELOG="${CHANGELOG}**Release Type**: ${RELEASE_TYPE}\n"
          CHANGELOG="${CHANGELOG}**Full Changelog**: https://github.com/${{ github.repository }}/compare/${LATEST_TAG:-initial}...v${VERSION}\n"

          # Escape for multiline output (random delimiter prevents collision with commit messages)
          DELIMITER="CHANGELOG_$(openssl rand -hex 16)"
          echo "changelog<<${DELIMITER}" >> $GITHUB_OUTPUT
          echo -e "$CHANGELOG" >> $GITHUB_OUTPUT
          echo "${DELIMITER}" >> $GITHUB_OUTPUT
          echo "changelog_file=CHANGELOG.md" >> $GITHUB_OUTPUT

          # Also write to step summary
          echo "## Generated Changelog" >> $GITHUB_STEP_SUMMARY
          echo "" >> $GITHUB_STEP_SUMMARY
          echo -e "$CHANGELOG" >> $GITHUB_STEP_SUMMARY