name: Auto Release on package.json version bump

on:
    push:
        branches: [v3]
        paths:
            - package.json

permissions:
    contents: write

jobs:
    release:
        runs-on: ubuntu-latest

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

            - name: Read current version
              id: current
              run: |
                  VERSION=$(node -p "require('./package.json').version")
                  echo "version=$VERSION" >> "$GITHUB_OUTPUT"

            - name: Read previous version (from previous commit)
              id: previous
              run: |
                  PREV_VERSION=$(git show HEAD~1:package.json 2>/dev/null | node -p "JSON.parse(require('fs').readFileSync(0,'utf8')).version" || echo "")
                  echo "version=$PREV_VERSION" >> "$GITHUB_OUTPUT"

            - name: Check if version increased
              id: check
              run: |
                  CUR="${{ steps.current.outputs.version }}"
                  PREV="${{ steps.previous.outputs.version }}"

                  echo "Current: $CUR"
                  echo "Previous: $PREV"

                  # if previous doesn't exist (first commit containing package.json), skip
                  if [ -z "$PREV" ]; then
                    echo "should_release=false" >> "$GITHUB_OUTPUT"
                    exit 0
                  fi

                  # Compare semver using node's semver package if available; fallback to simple inequality
                  node -e "
                    const cur='${CUR}';
                    const prev='${PREV}';
                    let should = cur !== prev;
                    try {
                      const semver = require('semver');
                      should = semver.gt(cur, prev);
                    } catch (_) {}
                    console.log('should_release=' + should);
                  " >> "$GITHUB_OUTPUT"

            - name: Stop if no bump
              if: steps.check.outputs.should_release != 'true'
              run: echo "No version increase detected."

            - name: Create tag + GitHub Release
              if: steps.check.outputs.should_release == 'true'
              uses: softprops/action-gh-release@v2
              with:
                  tag_name: v${{ steps.current.outputs.version }}
                  name: v${{ steps.current.outputs.version }}
                  generate_release_notes: true