#!/usr/bin/env bash

set -euo pipefail

repo_root="$(cd "$(dirname "$0")/.." && pwd)"
cd "$repo_root"

if [[ -z "${GITHUB_REF_NAME:-}" ]]; then
  echo "GITHUB_REF_NAME is required" >&2
  exit 1
fi

if [[ -z "${GITHUB_REPOSITORY:-}" || -z "${GITHUB_SERVER_URL:-}" || -z "${GITHUB_TOKEN:-}" ]]; then
  echo "GITHUB_REPOSITORY, GITHUB_SERVER_URL, and GITHUB_TOKEN are required" >&2
  exit 1
fi

tag="${GITHUB_REF_NAME}"
version="${tag#v}"
notes_file="$(mktemp)"

awk -v version="$version" '
  $0 ~ ("^## \\\[" version "\\\] - ") { in_section = 1 }
  /^## \[/ && in_section && $0 !~ ("^## \\\[" version "\\\] - ") { exit }
  in_section { print }
' CHANGELOG.md > "$notes_file"

if [[ ! -s "$notes_file" ]]; then
  printf '## [%s]\n\n- Release %s\n' "$version" "$tag" > "$notes_file"
fi

payload_file="$(mktemp)"
jq -n \
  --arg tag "$tag" \
  --arg name "$tag" \
  --arg target "main" \
  --rawfile body "$notes_file" \
  '{tag_name: $tag, target_commitish: $target, name: $name, body: $body, draft: false, prerelease: false}' > "$payload_file"

api_base="${GITHUB_SERVER_URL}/api/v1/repos/${GITHUB_REPOSITORY}"
status="$(curl -sS -o /tmp/release_lookup.json -w '%{http_code}' \
  -H "Authorization: token ${GITHUB_TOKEN}" \
  -H 'accept: application/json' \
  "${api_base}/releases/tags/${tag}" || true)"

if [[ "$status" == "200" ]]; then
  release_id="$(jq -r '.id' /tmp/release_lookup.json)"
  curl -fsSL -X PATCH \
    -H "Authorization: token ${GITHUB_TOKEN}" \
    -H 'accept: application/json' \
    -H 'content-type: application/json' \
    --data @"$payload_file" \
    "${api_base}/releases/${release_id}" >/dev/null
  echo "Updated release ${tag}."
else
  curl -fsSL -X POST \
    -H "Authorization: token ${GITHUB_TOKEN}" \
    -H 'accept: application/json' \
    -H 'content-type: application/json' \
    --data @"$payload_file" \
    "${api_base}/releases" >/dev/null
  echo "Created release ${tag}."
fi