name: Automated Arch ISO Build

on:
  schedule:
    - cron: "0 0 1 * *" # Runs monthly on the 1st day of the month
  workflow_dispatch: # Allows manual triggers (multiple times a month)

concurrency:
  group: iso-build
  cancel-in-progress: false # Never kill a build that is mid-flight

jobs:
  build:
    runs-on: archlinux
    permissions:
      contents: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

      - name: Setup local AUR repo
        run: |
          set -euo pipefail
          mkdir -p /tmp/localrepo
          cp localrepo/*.pkg.tar.zst localrepo/local-aur.db* localrepo/local-aur.files* /tmp/localrepo/
          sed -i 's|file:///home/alvin/alvinarch/localrepo|file:///tmp/localrepo|' pacman.conf

      - name: Install archiso and dependencies
        run: |
          set -euo pipefail
          pacman -Syu --noconfirm --needed archiso jq

      - name: Build Arch ISO
        run: |
          set -euo pipefail
          # Clean up immediately even if this step is interrupted (cancel/exit):
          # unmount leftovers first, then remove the multi-GB work dir.
          trap 'umount -R "$PWD/work" 2>/dev/null || true; rm -rf "$PWD/work"' EXIT HUP INT TERM
          rm -rf "$PWD/work"
          # Always start from an empty out dir so stale ISOs are never re-uploaded
          rm -rf "$PWD/out"
          mkdir -p "$PWD/out"
          mkarchiso -v -w "$PWD/work" -o "$PWD/out" -- "$PWD"

      - name: Generate Unique Dynamic Tag
        id: tag
        env:
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
          GITEA_API: http://192.168.1.168:3000/api/v1
          REPOSITORY: ${{ github.repository }}
        run: |
          set -euo pipefail
          test -n "$GITEA_TOKEN"

          # Pre-flight: confirm the internal Gitea API is reachable so failures are clear
          if ! curl -sfS -o /dev/null "$GITEA_API/version"; then
            echo "❌ Cannot reach Gitea API at $GITEA_API" >&2
            exit 1
          fi

          BASE_DATE=$(date -u +'%Y.%m.%d')
          REVISION=1
          TAG_NAME="iso-${BASE_DATE}-r${REVISION}"

          # Check if the tag already exists via Gitea API, increment revision loop if it does
          while curl -sf -o /dev/null -H "Authorization: token $GITEA_TOKEN" \
            "$GITEA_API/repos/$REPOSITORY/releases/tags/$TAG_NAME"; do
            REVISION=$((REVISION + 1))
            TAG_NAME="iso-${BASE_DATE}-r${REVISION}"
          done

          echo "tag_name=${TAG_NAME}" >> "$GITHUB_OUTPUT"
          echo "release_name=Arch Linux ISO (${BASE_DATE} Rev ${REVISION})" >> "$GITHUB_OUTPUT"

      - name: Create Release and Upload ISO
        env:
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
          # Use internal Gitea URL to bypass traefik proxy timeout on large uploads
          GITEA_API: http://192.168.1.168:3000/api/v1
          REPOSITORY: ${{ github.repository }}
          TAG_NAME: ${{ steps.tag.outputs.tag_name }}
          RELEASE_NAME: ${{ steps.tag.outputs.release_name }}
        run: |
          set -euo pipefail
          shopt -s nullglob
          test -n "$GITEA_TOKEN"
          test -n "$TAG_NAME"
          test -n "$RELEASE_NAME"

          # Pre-flight: confirm the internal Gitea API is reachable so failures are clear
          if ! curl -sfS -o /dev/null "$GITEA_API/version"; then
            echo "❌ Cannot reach Gitea API at $GITEA_API" >&2
            exit 1
          fi

          # Create the release via Gitea API (internal, no traefik)
          RELEASE_ID=$(curl -sf -X POST \
            -H "Authorization: token $GITEA_TOKEN" \
            -H "Content-Type: application/json" \
            "$GITEA_API/repos/$REPOSITORY/releases" \
            -d "{\"tag_name\": \"$TAG_NAME\", \"name\": \"$RELEASE_NAME\"}" \
            | jq -er '.id')

          echo "Created release ID: $RELEASE_ID"

          # Collect the ISOs produced by the build
          isos=(out/*.iso)
          if (( ${#isos[@]} == 0 )); then
            echo "❌ No ISO found in out/ — nothing to upload, aborting." >&2
            exit 1
          fi

          for iso in "${isos[@]}"; do
            fname=$(basename "$iso")
            size=$(stat -c %s "$iso")
            # Sanity check: a real ISO is multi-GB; anything tiny is the wrong file
            if (( size < 100000000 )); then
              echo "❌ '$iso' is only $size bytes — refusing to upload (not an ISO)." >&2
              exit 1
            fi

            echo "Uploading $fname ($(( size / 1024 / 1024 )) MiB)..."

            http_code=""
            for attempt in 1 2 3; do
              http_code=$(curl -sS --max-time 1800 \
                -o /dev/null -w "%{http_code}" \
                -H "Authorization: token $GITEA_TOKEN" \
                -F "attachment=@$iso;filename=$fname" \
                "$GITEA_API/repos/$REPOSITORY/releases/$RELEASE_ID/assets" || true)

              if [[ "$http_code" == "201" ]]; then
                echo "  ✅ Upload OK (HTTP 201) on attempt $attempt"
                break
              fi
              echo "  ⚠️  Upload attempt $attempt returned HTTP $http_code — retrying..." >&2
              sleep 5
            done

            if [[ "$http_code" != "201" ]]; then
              echo "❌ Failed to upload '$fname' (last HTTP code: $http_code)" >&2
              exit 1
            fi

            # Verify the exact asset made it: correct name AND byte size
            confirmed=$(curl -sf -H "Authorization: token $GITEA_TOKEN" \
              "$GITEA_API/repos/$REPOSITORY/releases/$RELEASE_ID/assets" \
              | jq -er --arg n "$fname" --argjson s "$size" \
                'first(.[] | select(.name == $n and .size == $s) | .name) // empty')
            if [[ -z "$confirmed" ]]; then
              echo "❌ Verification failed: asset '$fname' ($size bytes) not found on the release." >&2
              exit 1
            fi
            echo "  ✅ Verified '$confirmed' ($size bytes) attached to $TAG_NAME"
          done

          echo "Release $TAG_NAME created and ISOs uploaded."

      - name: Keep only latest 3 releases
        if: success()
        env:
          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
          GITEA_API: http://192.168.1.168:3000/api/v1
          REPOSITORY: ${{ github.repository }}
        run: |
          set -euo pipefail
          test -n "$GITEA_TOKEN"

          # Fetch all release ids, oldest first
          readarray -t ids < <(curl -sf -H "Authorization: token $GITEA_TOKEN" \
            "$GITEA_API/repos/$REPOSITORY/releases" \
            | jq -er 'sort_by(.created_at) | .[].id')

          # Delete the oldest releases, keeping only the 3 newest
          to_delete=$(( ${#ids[@]} - 3 ))
          if (( to_delete > 0 )); then
            for ((i = 0; i < to_delete; i++)); do
              id=${ids[$i]}
              echo "Deleting old release ID: $id"
              curl -sf -X DELETE -H "Authorization: token $GITEA_TOKEN" \
                "$GITEA_API/repos/$REPOSITORY/releases/$id"
            done
          fi

      - name: Cleanup mkarchiso mounts and workdirs
        if: always() # Runs on success, failure, or cancellation
        run: |
          set -eu
          # Steps run as root (pacman is used directly); fall back to sudo if not
          if [ "$(id -u)" -eq 0 ]; then
            PRIV=""
          else
            PRIV="sudo"
          fi

          # Unmount any leftover loop devices or bind mounts in the work directory
          $PRIV umount -R "$PWD/work" 2>/dev/null || true

          # Clean up loop devices if any remain attached to the work dir
          $PRIV losetup -D || true

          # Remove working directories with proper permissions
          $PRIV rm -rf "$PWD/work"

      - name: Remove built ISO (success or cancellation)
        if: success() || cancelled()
        run: |
          set -eu
          # On failure the ISO is kept in out/ for manual upload
          rm -rf "$PWD/out"