name: Notify

# Opens an issue when a package fails to update on main, so it shows up in the
# notifications on git.felo.gg. One issue per package: a broken package must
# not hide behind another one, and a run of only some packages must not close
# the issues of the others. A later failure refreshes the issue instead of
# commenting, as the schedule would otherwise add one every 6 hours. The next
# successful update of that package closes it again.
#
# Talks to the Gitea API with curl: gh only knows GitHub.

on:
  workflow_run:
    workflows: [Update AUR packages]
    types: [completed]

permissions:
  actions: read
  issues: write

concurrency:
  group: notify
  cancel-in-progress: false

jobs:
  notify:
    name: Notify
    runs-on: ubuntu-latest
    if: >-
      github.event.workflow_run.event != 'pull_request' &&
      github.event.workflow_run.head_branch == github.event.repository.default_branch
    steps:
      - name: Open, update or close the failure issues
        env:
          TOKEN: ${{ github.token }}
          API: ${{ github.api_url }}/repos/${{ github.repository }}
          OWNER: ${{ github.repository_owner }}
          WORKFLOW: ${{ github.event.workflow_run.name || 'Update AUR packages' }}
          CONCLUSION: ${{ github.event.workflow_run.conclusion }}
          EVENT: ${{ github.event.workflow_run.event }}
          RUN_ID: ${{ github.event.workflow_run.id }}
          RUN_URL: ${{ github.event.workflow_run.html_url }}
          SHA: ${{ github.event.workflow_run.head_sha }}
        run: |
          set -euo pipefail
          label=ci-failure

          api() {
            local method=$1 path=$2
            shift 2
            curl -fsSL -X "$method" -H "Authorization: token $TOKEN" \
              -H 'Content-Type: application/json' "$API$path" "$@"
          }

          issues="$(api GET "/issues?state=open&type=issues&labels=$label&limit=50")"

          label_id() {
            local id
            id="$(api GET '/labels?limit=50' | jq -r --arg l "$label" '.[] | select(.name == $l) | .id')"
            if [ -z "$id" ]; then
              id="$(api POST /labels -d "$(jq -cn --arg l "$label" \
                '{name: $l, color: "#d73a4a", description: "A package fails to update"}')" | jq -r .id)"
            fi
            echo "$id"
          }

          # The issue title for a job: the package for "update (<package>)",
          # the workflow for anything else.
          title_for() {
            if [[ $1 =~ ^update\ \((.+)\)$ ]]; then
              echo "${BASH_REMATCH[1]} fails to update"
            else
              echo "$WORKFLOW is failing"
            fi
          }

          issue_for() {
            jq -r --arg title "$1" '.[] | select(.title == $title) | .number' <<<"$issues" | head -1
          }

          # The lines of the failed step leading up to its first error, enough
          # to see what broke without opening the log. Falls back to the end
          # of the log.
          excerpt_for() {
            local log
            log="$(api GET "/actions/jobs/$1/logs" |
              sed -E 's/^[0-9TZ:.-]+ //; s/\x1b\[[0-9;]*m//g')" || return 0
            awk '/^(##\[group\]|::group::)Run / { out = "" } { out = out $0 "\n" }
              /^(##\[error\]|::error::)/ { printf "%s", out; found = 1; exit }
              END { if (!found) exit 1 }' <<<"$log" | tail -40 ||
              tail -40 <<<"$log"
          }

          # report <title> <job json, or empty if the run never started>
          report() {
            local title=$1 job=$2 line excerpt="" issue body
            if [ -n "$job" ]; then
              line="$(jq -r '"- [\(.name)](\(.html_url))" +
                ([.steps[]? | select(.conclusion == "failure") | .name] |
                  if length > 0 then ": " + join(", ") else "" end)' <<<"$job")"
              excerpt="$(excerpt_for "$(jq -r .id <<<"$job")")"
            else
              line="The run did not start ($CONCLUSION)."
            fi

            body="$(cat <<EOF
          [$WORKFLOW]($RUN_URL) failed on \`${SHA:0:7}\`, started by \`$EVENT\`.

          $line
          EOF
            )"
            if [ -n "$excerpt" ]; then
              body="$body

          <details>
          <summary>Log</summary>

          \`\`\`
          $excerpt
          \`\`\`

          </details>"
            fi

            issue="$(issue_for "$title")"
            if [ -n "$issue" ]; then
              api PATCH "/issues/$issue" -d "$(jq -cn --arg b "$body" '{body: $b}')" >/dev/null
            else
              api POST /issues -d "$(jq -cn --arg t "$title" --arg b "@$OWNER $body" \
                --argjson l "$(label_id)" '{title: $t, body: $b, labels: [$l]}')" >/dev/null
            fi
          }

          close() {
            local issue
            issue="$(issue_for "$1")"
            if [ -n "$issue" ]; then
              api POST "/issues/$issue/comments" \
                -d "$(jq -cn --arg b "Passing again: $RUN_URL" '{body: $b}')" >/dev/null
              api PATCH "/issues/$issue" -d '{"state": "closed"}' >/dev/null
            fi
          }

          if [ "$CONCLUSION" = startup_failure ]; then
            report "$WORKFLOW is failing" ""
            exit 0
          fi

          # Cancelled and skipped jobs say nothing about a package.
          page=1
          while :; do
            jobs="$(api GET "/actions/runs/$RUN_ID/jobs?limit=50&page=$page" | jq -c '.jobs[]?')"
            [ -n "$jobs" ] || break
            while IFS= read -r -u 3 job; do
              title="$(title_for "$(jq -r .name <<<"$job")")"
              case "$(jq -r .conclusion <<<"$job")" in
              success) close "$title" ;;
              failure | timed_out) report "$title" "$job" ;;
              esac
            done 3<<<"$jobs"
            [ "$(wc -l <<<"$jobs")" -ge 50 ] || break
            page=$((page + 1))
          done