name: Publish AUR Package

# Builds and pushes the `triple-c-bin` AUR package (packaging/arch/PKGBUILD)
# for a given release, or the latest one if none is given. Manual dispatch
# only — deliberately not triggered by `release` or `push`, for the same
# reason sync-release.yml (removed in triple-c#32) never worked safely as an
# automatic trigger: this repo's releases are assembled by build-app.yml
# across three separate platform jobs, and there is no single automatic event
# that fires only once everything (including the Linux .deb this workflow
# needs) is actually uploaded. A human deciding "this release is ready, go
# package it" is the correct trigger, the same reasoning
# backfill-releases.yml already uses for its own manual-only GitHub sync.
#
# ## What this does and does not do
#
# It renders `packaging/arch/PKGBUILD` for one specific version (real
# download URL, real sha256sums — never guessed; see the resolve-asset step)
# and pushes the rendered PKGBUILD plus a regenerated `.SRCINFO` to AUR. It
# does NOT commit anything back to this repo — `packaging/arch/PKGBUILD` stays
# a hand-maintained template with a placeholder version, and every real,
# published version lives only in AUR's own git history, which is where a
# PKGBUILD's revision history is expected to live. A corollary worth knowing:
# a hand-edit made directly in the AUR repo (outside this workflow) is
# silently overwritten the next time this runs, since every run renders fresh
# from this repo's template rather than starting from AUR's current state.
#
# ## Required secret
#
# `AUR_SSH_PRIVATE_KEY` — an SSH private key registered against an AUR
# account that has already created (or been given co-maintainer access to)
# the `triple-c-bin` package. This workflow cannot create that AUR account or
# register the key for you — both are manual, one-time steps on
# https://aur.archlinux.org. Until this secret exists, every run fails at the
# "Push to AUR" step with a clear error rather than silently doing nothing.
on:
  workflow_dispatch:
    inputs:
      version:
        description: >-
          Release version to package, without a leading "v" (e.g. "0.4.14").
          Leave empty to use the latest published GitHub release.
        required: false

env:
  GITHUB_REPO: shadowdao/triple-c
  AUR_REPO: ssh://aur@aur.archlinux.org/triple-c-bin.git

jobs:
  publish:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Resolve version and find the Linux asset
        id: resolve
        env:
          VERSION_INPUT: ${{ inputs.version }}
          GH_PAT: ${{ secrets.GH_PAT }}
        run: |
          set -euo pipefail

          # Authenticated when the secret is available (it is, everywhere
          # else in this repo's workflows) to avoid the unauthenticated
          # 60-requests/hour-per-IP cap; still works without it, just at that
          # lower limit, since this hits nothing but a public repo's public
          # releases.
          AUTH=()
          [ -n "${GH_PAT}" ] && AUTH=(-H "Authorization: Bearer ${GH_PAT}")

          if [ -z "${VERSION_INPUT}" ]; then
            echo "No version given — resolving the latest GitHub release"
            RELEASE_JSON=$(curl -fsS "${AUTH[@]}" "https://api.github.com/repos/${GITHUB_REPO}/releases/latest")
          else
            echo "Using requested version ${VERSION_INPUT}"
            RELEASE_JSON=$(curl -fsS "${AUTH[@]}" "https://api.github.com/repos/${GITHUB_REPO}/releases/tags/v${VERSION_INPUT}")
          fi

          TAG=$(echo "$RELEASE_JSON" | jq -r '.tag_name')
          VERSION="${TAG#v}"
          echo "Resolved to ${TAG}"

          # Discovered from the real release, not assumed: Tauri names the
          # asset after `productName` verbatim ("Triple-C"), not the
          # lowercase Cargo binary name, and asset naming is exactly the kind
          # of thing that silently drifts if a future Tauri upgrade changes
          # bundler defaults — a hardcoded pattern here would then 404
          # forever until someone noticed. `head -1` guards against a release
          # somehow carrying more than one matching asset, which would
          # otherwise pass the emptiness check below and then break the
          # download step with two URLs on one line.
          DEB_URL=$(echo "$RELEASE_JSON" | jq -r '.assets[] | select(.name | endswith("_amd64.deb")) | .browser_download_url' | head -1)
          DEB_NAME=$(echo "$RELEASE_JSON" | jq -r '.assets[] | select(.name | endswith("_amd64.deb")) | .name' | head -1)
          if [ -z "$DEB_URL" ] || [ "$DEB_URL" = "null" ]; then
            echo "No *_amd64.deb asset found on release ${TAG}" >&2
            exit 1
          fi
          echo "Found asset: ${DEB_NAME}"

          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
          echo "tag=${TAG}" >> "$GITHUB_OUTPUT"
          echo "deb_url=${DEB_URL}" >> "$GITHUB_OUTPUT"
          echo "deb_name=${DEB_NAME}" >> "$GITHUB_OUTPUT"

      - name: Download the release asset and compute real checksums
        id: checksums
        env:
          DEB_URL: ${{ steps.resolve.outputs.deb_url }}
          DEB_NAME: ${{ steps.resolve.outputs.deb_name }}
          TAG: ${{ steps.resolve.outputs.tag }}
        run: |
          set -euo pipefail
          curl -fsSL -o "${DEB_NAME}" "${DEB_URL}"
          curl -fsSL -o LICENSE "https://raw.githubusercontent.com/${GITHUB_REPO}/${TAG}/LICENSE"

          echo "deb_sha256=$(sha256sum "${DEB_NAME}" | cut -d' ' -f1)" >> "$GITHUB_OUTPUT"
          echo "license_sha256=$(sha256sum LICENSE | cut -d' ' -f1)" >> "$GITHUB_OUTPUT"

      - name: Render PKGBUILD
        id: render
        env:
          VERSION: ${{ steps.resolve.outputs.version }}
          DEB_NAME: ${{ steps.resolve.outputs.deb_name }}
          DEB_SHA256: ${{ steps.checksums.outputs.deb_sha256 }}
          LICENSE_SHA256: ${{ steps.checksums.outputs.license_sha256 }}
        run: |
          set -euo pipefail
          mkdir -p rendered
          cp packaging/arch/PKGBUILD rendered/PKGBUILD
          cd rendered

          # Plain string replacement throughout, not sed — the source URL
          # contains slashes and the repo name does too, and getting a sed
          # delimiter choice AND its escaping right for that is exactly the
          # kind of thing that looks correct, passes review, and breaks the
          # next time someone touches it. `re.sub` with `count=1` and an
          # exact `.format`-free literal match is boring and that's the
          # point: every substitution below fails loudly (an assertion /
          # the checks after) rather than silently no-op'ing if the
          # template's shape ever drifts from what this expects.
          #
          # pkgrel resets to 1 for a new pkgver — a packaging-only fix to the
          # same upstream version (a dependency bump, say) is what pkgrel is
          # for, and this workflow always republishes the current PKGBUILD
          # verbatim rather than incrementing anything, so 1 is always
          # correct for what this workflow does. It is NOT correct for a
          # dependency-only fix republished at the *same* pkgver: pkgrel
          # would be forced back to 1, and no existing installation sees an
          # upgrade. That case needs a manual pkgrel bump in the template
          # before dispatching, which this workflow has no input for.
          python3 - "$VERSION" "$DEB_NAME" "$DEB_SHA256" "$LICENSE_SHA256" "$GITHUB_REPO" <<'PY'
          import re, sys
          version, deb_name, deb_sha, license_sha, github_repo = sys.argv[1:6]

          with open("PKGBUILD") as f:
              text = f.read()

          text, n = re.subn(r"(?m)^pkgver=.*$", f"pkgver={version}", text, count=1)
          assert n == 1, "pkgver=... line not found"
          text, n = re.subn(r"(?m)^pkgrel=.*$", "pkgrel=1", text, count=1)
          assert n == 1, "pkgrel=... line not found"

          # Built with a "$" variable and plain "+" concatenation rather than
          # an f-string's double-brace escape for a literal brace: writing
          # this as an f-string put a dollar sign directly against two open
          # braces, right here in this workflow's own YAML text — and this
          # runner's own expression templating scans a run: block for that
          # exact two-character opening sequence and tries to evaluate
          # whatever sits inside as one of ITS OWN expressions (a step
          # output, a secret, ...) before the shell ever sees this script.
          # "pkgver" isn't one of those, so that lookup failed and silently
          # emptied this whole step rather than raising anything here.
          # Spelling the dollar sign out of a variable instead means this
          # file's own text never contains that trigger sequence.
          DOLLAR = "$"
          old_source = (
              "source=(\"Triple-C_" + DOLLAR + "{pkgver}_amd64.deb::"
              + "https://github.com/" + github_repo + "/releases/download/v" + DOLLAR + "{pkgver}/"
              + "Triple-C_" + DOLLAR + "{pkgver}_amd64.deb\""
          )
          new_source = (
              f'source=("{deb_name}::'
              f'https://github.com/{github_repo}/releases/download/v{version}/{deb_name}"'
          )
          assert old_source in text, "source=() line does not match the expected template shape"
          text = text.replace(old_source, new_source, 1)

          old_sums = "sha256sums=('SKIP'\n            'SKIP')"
          assert old_sums in text, "sha256sums=() placeholders not found"
          text = text.replace(old_sums, f"sha256sums=('{deb_sha}'\n            '{license_sha}')", 1)

          with open("PKGBUILD", "w") as f:
              f.write(text)
          PY

          grep -q "pkgver=${VERSION}$" PKGBUILD
          ! grep -q "SKIP" PKGBUILD

      - name: Validate with makepkg and namcap
        run: |
          set -euo pipefail

          # A bind mount (`docker run -v "$PWD/...":/work`) is the more
          # obvious way to write this, and was the first draft — but on a
          # containerized Gitea act_runner job, `$PWD` is a path inside this
          # job's own container, which the daemon's host cannot resolve; the
          # mount would silently attach an empty directory instead of failing
          # loudly. `docker cp` moves real bytes across that boundary
          # regardless of where the daemon actually lives, which is what
          # makes this work under both a bind-mount-capable runner and a
          # containerized one.
          docker pull archlinux:latest
          CID=$(docker create -w /work archlinux:latest bash -c '
            set -euo pipefail
            pacman -Syu --noconfirm --needed base-devel namcap sudo git openssh >/dev/null
            useradd -m builder
            chown -R builder:builder /work
            echo "builder ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers.d/builder
            sudo -u builder bash -c "cd /work && makepkg --printsrcinfo > .SRCINFO"
            sudo -u builder bash -c "cd /work && makepkg -s --noconfirm"
            echo "--- namcap ---"
            NAMCAP_OUT=$(sudo -u builder bash -c "cd /work && namcap PKGBUILD *.pkg.tar.*" || true)
            echo "$NAMCAP_OUT"
            # Matches "triple-c-bin E:", "PKGBUILD (triple-c-bin) E:" and any
            # split-package variant ("triple-c-bin-debug E:") alike — namcap
            # uses more than one line shape for its two rule families, and
            # namcap itself exits 0 regardless of what it reports, so this
            # grep is the only thing standing between an E: and a green job.
            if echo "$NAMCAP_OUT" | grep -q " E: "; then
              echo "namcap reported an error — see above" >&2
              exit 1
            fi
          ')
          mkdir -p rendered
          docker cp rendered/. "${CID}:/work"
          # `docker start -a` streams output and its exit code is the
          # container's own — the same failure this would have hit with a
          # bind mount still fails the job the same way.
          docker start -a "${CID}"
          docker cp "${CID}:/work/.SRCINFO" rendered/.SRCINFO
          docker rm -f "${CID}" >/dev/null

      - name: Push to AUR
        env:
          AUR_SSH_PRIVATE_KEY: ${{ secrets.AUR_SSH_PRIVATE_KEY }}
          VERSION: ${{ steps.resolve.outputs.version }}
        run: |
          set -euo pipefail
          if [ -z "${AUR_SSH_PRIVATE_KEY}" ]; then
            echo "AUR_SSH_PRIVATE_KEY is not set — see this workflow file's header comment for" >&2
            echo "the one-time AUR account setup this needs before it can publish anything." >&2
            exit 1
          fi

          mkdir -p ~/.ssh
          # Created with the final mode before any bytes land in it, rather
          # than a plain redirect followed by chmod, which leaves the key
          # world-readable for whatever window falls between the two calls.
          install -m 600 /dev/null ~/.ssh/aur
          echo "${AUR_SSH_PRIVATE_KEY}" > ~/.ssh/aur
          # TOFU, not verification — accepted here because pinning AUR's
          # actual host key needs a value fetched from somewhere trusted
          # ahead of time, which this workflow doesn't have, and getting a
          # pinned value wrong fails every future run rather than just this
          # one. A keyscan failure below surfaces later as an opaque
          # "Host key verification failed" rather than a clear one here.
          ssh-keyscan -H aur.archlinux.org >> ~/.ssh/known_hosts 2>/dev/null
          export GIT_SSH_COMMAND="ssh -i ~/.ssh/aur -o IdentitiesOnly=yes -o UserKnownHostsFile=~/.ssh/known_hosts"

          git clone "${AUR_REPO}" aur-repo
          cp rendered/PKGBUILD rendered/.SRCINFO aur-repo/
          cd aur-repo
          git config user.name "Triple-C CI"
          git config user.email "noreply@triple-c.invalid"
          git add PKGBUILD .SRCINFO
          if git diff --cached --quiet; then
            echo "No change from what's already published on AUR for ${VERSION}"
            exit 0
          fi
          git commit -m "triple-c-bin: update to ${VERSION}"
          # AUR itself uses `master`, which is what a fresh, not-yet-created
          # AUR package's empty repo advertises on clone — but the *local*
          # branch name after cloning an empty repo falls back to whatever
          # this runner's `init.defaultBranch` is if the server sends no
          # symref, so naming the destination explicitly is what keeps this
          # working if that default is ever `main` instead of `master`.
          git push origin HEAD:master