name: CI

# Pre-merge checks. Runs on the dev branch and on every pull request aimed at
# dev or main, so breakage is caught before it reaches main and triggers a
# release.
#
# On a push to dev it also publishes the build as a dev-channel prerelease, so
# the in-app updater can offer it to anyone who has switched to that channel.
# Prereleases are used deliberately: GitHub's "latest release" endpoint skips
# them, so a production-channel user never sees a dev build. Pull requests only
# build and check — they never publish, which keeps a PR from a fork from
# shipping anything.
on:
  push:
    branches: [ dev ]
  pull_request:
    branches: [ main, dev ]
  workflow_dispatch:

# Needed to publish the dev-channel prerelease below.
permissions:
  contents: write

# A newer push to the same branch or PR makes the in-flight run obsolete.
concurrency:
  group: ci-${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

jobs:
  build:
    name: Build and check
    runs-on: ubuntu-latest
    env:
      # Stamp the APK as a dev-channel build only when this is a real push to
      # dev. Pull request builds stay unstamped at 1.0.0-dev, since they are
      # never published and must not claim a channel version.
      PLG_CHANNEL: ${{ (github.event_name == 'push' && github.ref == 'refs/heads/dev') && 'dev' || '' }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Set up JDK 17
        uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: '17'
          cache: gradle

      - name: Set up Android SDK
        uses: android-actions/setup-android@v3

      - name: Build debug APK
        run: ./gradlew assembleDebug --no-daemon

      - name: Run unit tests
        run: ./gradlew testDebugUnitTest --no-daemon

      - name: Run Android lint
        run: ./gradlew lintDebug --no-daemon

      - name: Upload debug APK
        uses: actions/upload-artifact@v4
        with:
          name: ProLibertateGames-debug-apk
          path: app/build/outputs/apk/debug/app-debug.apk
          if-no-files-found: error
          retention-days: 14

      - name: Upload lint and test reports
        # Reports are most useful precisely when a step above failed.
        if: always()
        uses: actions/upload-artifact@v4
        with:
          name: ProLibertateGames-reports
          path: |
            app/build/reports/
          if-no-files-found: ignore
          retention-days: 14

      # Everything below publishes the dev channel, and only ever from a push
      # to dev that has already built, tested and linted clean above.
      - name: Stage dev APK
        id: stage
        if: github.event_name == 'push' && github.ref == 'refs/heads/dev'
        run: |
          set -euo pipefail
          version="v1.0.${{ github.run_number }}-dev"
          src="app/build/outputs/apk/debug/app-debug.apk"
          dest="ProLibertateGames-${version}.apk"
          cp "$src" "$dest"
          echo "version=$version" >> "$GITHUB_OUTPUT"
          echo "apk=$dest" >> "$GITHUB_OUTPUT"

      - name: Publish dev channel prerelease
        if: github.event_name == 'push' && github.ref == 'refs/heads/dev'
        env:
          GH_TOKEN: ${{ github.token }}
        run: |
          set -euo pipefail
          gh release create "${{ steps.stage.outputs.version }}" \
            "${{ steps.stage.outputs.apk }}" \
            --repo "${{ github.repository }}" \
            --target "${{ github.sha }}" \
            --title "ProLibertateGames ${{ steps.stage.outputs.version }}" \
            --prerelease \
            --notes "Automated **dev channel** build from \`${{ github.sha }}\` on \`dev\`.

          Preview build: newer than production, and less tested. Switch to the
          Dev update channel in Settings to be offered these. Marked as a
          prerelease so production-channel installs never see it."