name: Parse semver string
description: Parse a refs/tags/vX.Y.Z[-prerelease][+build] ref into version components. Falls back to 0.0.0 when not run on a version tag.
outputs:
  major:
    description: Major version number (e.g. "1" from v1.2.3).
    value: ${{ steps.parse.outputs.major }}
  minor:
    description: Minor version number (e.g. "2" from v1.2.3).
    value: ${{ steps.parse.outputs.minor }}
  patch:
    description: Patch version number (e.g. "3" from v1.2.3).
    value: ${{ steps.parse.outputs.patch }}
  prerelease:
    description: Prerelease identifier (e.g. "rc.1" from v1.2.3-rc.1), empty when absent.
    value: ${{ steps.parse.outputs.prerelease }}
  build:
    description: Build metadata (e.g. "build.7" from v1.2.3+build.7), empty when absent.
    value: ${{ steps.parse.outputs.build }}
  fullversion:
    description: MAJOR.MINOR.PATCH joined (e.g. "1.2.3").
    value: ${{ steps.parse.outputs.fullversion }}
runs:
  using: composite
  steps:
    - id: parse
      shell: bash
      run: |
        set -euo pipefail
        REF="${{ (startsWith(github.ref, 'refs/tags/v') && github.ref) || 'refs/tags/v0.0.0' }}"
        if [[ "$REF" =~ ^refs/tags/v([0-9]+)\.([0-9]+)\.([0-9]+)(-([0-9A-Za-z.-]+))?(\+([0-9A-Za-z.-]+))?$ ]]; then
          MAJOR="${BASH_REMATCH[1]}"
          MINOR="${BASH_REMATCH[2]}"
          PATCH="${BASH_REMATCH[3]}"
          PRERELEASE="${BASH_REMATCH[5]}"
          BUILD="${BASH_REMATCH[7]}"
        else
          MAJOR=0; MINOR=0; PATCH=0; PRERELEASE=""; BUILD=""
        fi
        {
          echo "major=$MAJOR"
          echo "minor=$MINOR"
          echo "patch=$PATCH"
          echo "prerelease=$PRERELEASE"
          echo "build=$BUILD"
          echo "fullversion=$MAJOR.$MINOR.$PATCH"
        } >> "$GITHUB_OUTPUT"