#!/usr/bin/env bash
# Open a pull request against main from the current branch.
#
#   scripts/pr.sh "feat(ingest): parse Bryton FIT activities" [--draft]
#
# Requires GITEA_TOKEN (scopes: write:repository, write:issue) and optionally GITEA_URL.
set -euo pipefail

GITEA_URL="${GITEA_URL:-http://192.168.0.3:3000}"
OWNER="${GITEA_OWNER:-BBergle}"
REPO="${GITEA_REPO:-bike-app}"
BASE="${PR_BASE:-main}"

die() { echo "error: $*" >&2; exit 1; }

[ -n "${GITEA_TOKEN:-}" ] || die "GITEA_TOKEN is not set. See CONTRIBUTING.md."
command -v jq >/dev/null || die "jq is required (brew install jq)."

TITLE="${1:-}"
[ -n "$TITLE" ] || die "usage: scripts/pr.sh \"<title>\" [--draft]"
DRAFT=false
[ "${2:-}" = "--draft" ] && DRAFT=true

BRANCH="$(git rev-parse --abbrev-ref HEAD)"
[ "$BRANCH" != "$BASE" ] || die "refusing to open a PR from $BASE onto itself."

git diff --quiet && git diff --cached --quiet || die "working tree is dirty; commit or stash first."

if ! git rev-parse --verify "origin/$BRANCH" >/dev/null 2>&1; then
  echo "Branch not on the remote yet; pushing."
  git push -u origin "$BRANCH"
fi

# Prefer the PR template; otherwise summarise the commits on this branch.
if [ -f .gitea/PULL_REQUEST_TEMPLATE.md ]; then
  BODY="$(cat .gitea/PULL_REQUEST_TEMPLATE.md)"
else
  BODY="$(git log --format='- %s' "origin/$BASE..$BRANCH")"
fi

RESPONSE="$(jq -n \
  --arg title "$TITLE" --arg body "$BODY" \
  --arg head "$BRANCH" --arg base "$BASE" \
  --argjson draft "$DRAFT" \
  '{title:$title, body:$body, head:$head, base:$base}' \
  | curl -sS -X POST \
      -H "Authorization: token $GITEA_TOKEN" \
      -H "Content-Type: application/json" \
      -d @- \
      "$GITEA_URL/api/v1/repos/$OWNER/$REPO/pulls")"

if URL="$(echo "$RESPONSE" | jq -er '.html_url' 2>/dev/null)"; then
  echo "PR opened: $URL"
else
  echo "Gitea rejected the request:" >&2
  echo "$RESPONSE" | jq . >&2 2>/dev/null || echo "$RESPONSE" >&2
  exit 1
fi