name: Monthly Sync

on:
  schedule:
    - cron: "0 0 1 * *" # Monthly on the 1st at 00:00 UTC
  workflow_dispatch:
    inputs:
      force_release:
        description: "Force release even if no changes?"
        type: boolean
        default: false

env:
  UPSTREAM_BRANCH: main # Will auto-detect if upstream uses 'master' instead

jobs:
  sync-and-release:
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          fetch-depth: 0
          token: ${{ secrets.CI_PAT_TOKEN }}

      - name: Get upstream URL from fork parent
        id: get-upstream
        run: |
          # Get parent repository URL from GitHub API
          UPSTREAM_URL=$(curl -s -H "Authorization: token ${{ secrets.GITHUB_TOKEN }}" \
            "https://api.github.com/repos/${{ github.repository }}" | \
            jq -r '.parent.html_url')

          if [ -z "$UPSTREAM_URL" ] || [ "$UPSTREAM_URL" = "null" ]; then
            echo "Error: Could not get upstream URL. Is this repository a fork?"
            exit 1
          fi

          echo "Upstream URL: $UPSTREAM_URL"
          echo "upstream_url=$UPSTREAM_URL" >> $GITHUB_OUTPUT

      - name: Configure Git
        run: |
          git config user.name "github-actions[bot]"
          git config user.email "github-actions[bot]@users.noreply.github.com"

      - name: Detect upstream default branch
        id: detect-branch
        run: |
          UPSTREAM_URL="${{ steps.get-upstream.outputs.upstream_url }}"

          # Add upstream remote
          git remote add upstream "$UPSTREAM_URL"
          git fetch upstream

          # Try to detect default branch
          UPSTREAM_BRANCH=$(git remote show upstream | grep 'HEAD branch' | cut -d' ' -f5)

          if [ -z "$UPSTREAM_BRANCH" ]; then
            # Fallback to env default
            UPSTREAM_BRANCH="${{ env.UPSTREAM_BRANCH }}"
          fi

          echo "Detected upstream branch: $UPSTREAM_BRANCH"
          echo "branch=$UPSTREAM_BRANCH" >> $GITHUB_OUTPUT

      - name: Merge upstream changes
        run: |
          UPSTREAM_BRANCH="${{ steps.detect-branch.outputs.branch }}"
          CURRENT_BRANCH=$(git branch --show-current)

          echo "Current branch: $CURRENT_BRANCH"
          echo "Syncing from upstream branch: $UPSTREAM_BRANCH"

          # Merge upstream changes
          git merge upstream/$UPSTREAM_BRANCH --no-edit || {
            echo "Merge conflict detected. Manual intervention required."
            exit 1
          }

          # Push merged changes to current branch
          git push origin $CURRENT_BRANCH

      - name: Check changes and generate tag
        id: check
        run: |
          # Get the last tag
          LAST_TAG=$(git describe --tags --abbrev=0 2>/dev/null || echo "")

          # Get current and last tag commit hashes
          CURRENT_HASH=$(git rev-parse HEAD)
          if [ -n "$LAST_TAG" ]; then
            LAST_TAG_HASH=$(git rev-parse "$LAST_TAG^{}")
          else
            LAST_TAG_HASH=""
          fi

          echo "Last Tag: $LAST_TAG ($LAST_TAG_HASH)"
          echo "Current:  $CURRENT_HASH"

          # Skip if no changes and not forced
          if [ "$CURRENT_HASH" == "$LAST_TAG_HASH" ] && [ "${{ inputs.force_release }}" != "true" ]; then
            echo "No changes detected. Skipping release."
            echo "release_needed=false" >> $GITHUB_OUTPUT
            exit 0
          fi

          # Generate pseudo-version: v0.0.0-YYYYMMDD-commitHash
          SHORT_HASH=$(git rev-parse --short=7 HEAD)
          DATE_STR=$(date +'%Y%m%d')
          NEW_TAG="v0.0.0-${DATE_STR}-${SHORT_HASH}"

          # Check if tag already exists
          if git rev-parse "$NEW_TAG" >/dev/null 2>&1; then
             echo "Tag $NEW_TAG already exists. Skipping."
             echo "release_needed=false" >> $GITHUB_OUTPUT
             exit 0
          fi

          echo "New release will be: $NEW_TAG"
          echo "release_needed=true" >> $GITHUB_OUTPUT
          echo "new_tag=$NEW_TAG" >> $GITHUB_OUTPUT

      - name: Create GitHub release
        if: steps.check.outputs.release_needed == 'true'
        env:
          GH_TOKEN: ${{ secrets.CI_PAT_TOKEN }}
        run: |
          TAG_NAME="${{ steps.check.outputs.new_tag }}"
          UPSTREAM_URL="${{ steps.get-upstream.outputs.upstream_url }}"

          echo "Creating tag and release: $TAG_NAME"

          # Create and push tag
          git tag "$TAG_NAME"
          git push origin "$TAG_NAME"

          # Create GitHub release
          COMMIT_HASH=$(git rev-parse HEAD)
          RELEASE_NOTES="Synced with upstream $UPSTREAM_URL on $(date +'%Y-%m-%d').

          Commit: $COMMIT_HASH"

          gh release create "$TAG_NAME" \
            --repo ${{ github.repository }} \
            --title "Auto Release $TAG_NAME" \
            --notes "$RELEASE_NOTES" \
            --generate-notes