name: Setup build
description: >-
  Writes the GIT-* files GetSCMRev reads (so the build embeds the version this run was given instead
  of asking git), and restores the CPM and compiler-object caches. Run after actions/checkout.

inputs:
  platform:
    description: Platform name, used in the compiler cache key (for example linux-x86_64-pgo)
    required: true
  sha:
    description: Full commit SHA being built
    required: true
  refspec:
    description: Value for GIT-REFSPEC (the version label of a daily or branch build)
    required: true
  tag:
    description: Value for GIT-TAG
    required: true
  release:
    description: "true for stable and rc builds: writes GIT-RELEASE, which makes the build a release build"
    required: false
    default: "false"
  save-cache:
    description: Save the caches at the end of the job (they are always restored)
    required: false
    default: ${{ github.event_name == 'schedule' || github.ref == 'refs/heads/nx2' }}

runs:
  using: composite
  steps:
    - name: Write SCM files
      shell: bash
      env:
        SCM_SHA: ${{ inputs.sha }}
        SCM_REFSPEC: ${{ inputs.refspec }}
        SCM_TAG: ${{ inputs.tag }}
        SCM_RELEASE: ${{ inputs.release }}
      run: |
        set -euo pipefail
        printf '%s\n' "$SCM_SHA" > GIT-COMMIT
        printf '%s\n' "$SCM_REFSPEC" > GIT-REFSPEC
        printf '%s\n' "$SCM_TAG" > GIT-TAG
        if [ "$SCM_RELEASE" = true ]; then
          printf '%s\n' "$SCM_TAG" > GIT-RELEASE
        else
          rm -f GIT-RELEASE
        fi
        echo "GetSCMRev inputs:"
        head -v GIT-COMMIT GIT-REFSPEC GIT-TAG GIT-RELEASE 2> /dev/null || true

    - name: Cache CPM downloads (restore and save)
      if: inputs.save-cache == 'true'
      uses: actions/cache@v6
      with:
        path: .cache/cpm
        key: cpm-v1-${{ runner.os }}-${{ hashFiles('**/cpmfile.json') }}
        restore-keys: |
          cpm-v1-${{ runner.os }}-

    - name: Cache CPM downloads (restore only)
      if: inputs.save-cache != 'true'
      uses: actions/cache/restore@v6
      with:
        path: .cache/cpm
        key: cpm-v1-${{ runner.os }}-${{ hashFiles('**/cpmfile.json') }}
        restore-keys: |
          cpm-v1-${{ runner.os }}-

    # --- Compiler objects (ccache or sccache, whichever the job uses) ---
    # The "--" after the platform stops linux-x86_64 from matching linux-x86_64-pgo.
    # The sha makes every saving run write a fresh entry; restore-keys seeds it from the newest.
    - name: Cache compiler objects (restore and save)
      if: inputs.save-cache == 'true'
      uses: actions/cache@v6
      with:
        path: |
          .ccache
          .sccache
        key: objects-v1-${{ inputs.platform }}--${{ inputs.sha }}
        restore-keys: |
          objects-v1-${{ inputs.platform }}--

    - name: Cache compiler objects (restore only)
      if: inputs.save-cache != 'true'
      uses: actions/cache/restore@v6
      with:
        path: |
          .ccache
          .sccache
        key: objects-v1-${{ inputs.platform }}--${{ inputs.sha }}
        restore-keys: |
          objects-v1-${{ inputs.platform }}--