#!/bin/sh
# git merge-pr PRNUM[@REMOTE] [GIT-AM FLAGS...] - apply GitHub pull request from command-line
set -e

PR=${1?no pull request given}
REMOTE=
case "$PR" in
*@*)
	REMOTE=${PR#*@}
	PR=${PR%%@*}
esac
shift

URL=$(git ls-remote --get-url $REMOTE)

PROJECT=${URL%.git}
PROJECT=${PROJECT##*:}
PROJECT=${PROJECT#//github.com/}

PATCH="$(mktemp)"
trap "rm -f $PATCH" INT TERM EXIT
wget -nv -O "$PATCH" https://github.com/$PROJECT/pull/"$PR".patch
git am "$@" "$PATCH"

if [ "$(git config --bool --get merge-pr.autoclose)" = false ]; then
	exit 0
fi

# Rewrite last commit message to close GitHub issue.
EDITOR='sh -c '\''git -c trailer.closes.ifExists=replace interpret-trailers \
		--trailer "Closes: #'"$PR"' [via git-merge-pr]" "$1" > "$1-" &&
	mv "$1-" "$1"'\'' -' \
git commit --quiet --amend