#!/bin/bash
# Called by action.yml. Everything user-written (release name, notes) comes in
# through the event JSON file and is only ever handled by jq -- never spliced
# into a command line or a JSON string by the shell.
set -euo pipefail

category_path=$(jq -r --arg r "$REPO" '.[$r] // empty' "$MAP")
if [ -z "$category_path" ]; then
  echo "::error::$REPO is not in discourse-release/release-map.json"
  exit 1
fi

tag=$(jq -r '.release.tag_name' "$EVENT_PATH")
# The category id, looked up anonymously (the category is public); the
# release-bot key is scoped to creating posts and nothing else.
category_id=$(curl -fsS "$FORUM/c/$category_path/find_by_slug.json" | jq -r '.category.id')

# One topic per repo+tag, ever: Discourse enforces external_id uniqueness.
external_id="rel-$(printf '%s@%s' "$REPO" "$tag" | sha1sum | cut -c1-40)"

payload=$(jq -n --arg repo "$REPO" --argjson category "$category_id" --arg ext "$external_id" \
  --slurpfile ev "$EVENT_PATH" '
  ($ev[0].release) as $r
  | ($repo | split("/") | last) as $name
  | ($r.name // "" | if . == "" then $r.tag_name else . end) as $title
  | {
      title: "\($name) \($title) released",
      category: $category,
      external_id: $ext,
      raw: (
        "**\($name) \($r.tag_name)** is out.\n\n"
        + (if ($r.body // "") == "" then "" else "\($r.body)\n\n" end)
        + "---\n[Release on Gitea](\($r.html_url))"
      )
    }')

status=$(curl -sS -o /tmp/discourse-release.out -w '%{http_code}' -X POST "$FORUM/posts.json" \
  -H "Api-Key: $API_KEY" -H "Api-Username: release-bot" \
  -H "Content-Type: application/json" --data-binary "$payload")
body=$(cat /tmp/discourse-release.out)
case "$status" in
  200)
    url="$FORUM/t/$(jq -r '.topic_slug' <<<"$body")/$(jq -r '.topic_id' <<<"$body")"
    echo "announced: $url" ;;
  422)
    if jq -e '.errors | tostring | test("External ID"; "i")' <<<"$body" >/dev/null; then
      echo "already announced (external_id $external_id); nothing to do"
      exit 0
    fi
    echo "::error::forum refused the post: $body"; exit 1 ;;
  *)
    echo "::error::forum returned HTTP $status: $body"; exit 1 ;;
esac

if [ -n "${DISCORD_WEBHOOK:-}" ]; then
  jq -n --arg u "$url" --slurpfile ev "$EVENT_PATH" --arg repo "$REPO" '
    ($ev[0].release) as $r
    | {content: ("**\($repo | split("/") | last) \($r.tag_name)** released\n\($u)")[0:1900]}' |
  curl -fsS -X POST "$DISCORD_WEBHOOK" -H "Content-Type: application/json" --data-binary @- >/dev/null \
    && echo "posted to Discord" \
    || echo "::warning::Discord webhook failed; the forum post stands"
fi