#!/bin/bash -e
#
# Deploy your branch on VIP Go.
#

# This script uses various CircleCI, Travis CI or GitHub Actions environment
# variables. CircleCI prefix their environment variables with
# `CIRCLE_`, Travis with `TRAVIS_`, and GitHub Actions with `GITHUB_`.
# Documentation:
# https://circleci.com/docs/2.0/env-vars/#circleci-built-in-environment-variables
# https://docs.travis-ci.com/user/environment-variables/
# https://docs.github.com/en/actions/learn-github-actions/environment-variables

set -ex

# The deploy suffix flexibility is mainly here to allow
# us to test Circle and Travis builds simultaneously on
# the https://github.com/Automattic/vip-go-skeleton/ repo.
DEPLOY_SUFFIX="${VIP_DEPLOY_SUFFIX:--built}"

if [ -n "$CIRCLECI" ]; then
	BRANCH="$CIRCLE_BRANCH"
	REPO_SLUG="${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}"
	COMMIT_SHA="$CIRCLE_SHA1"
	# SRC_DIR="$CIRCLE_WORKING_DIRECTORY"
	SRC_DIR="$PWD"
	BUILD_URL="$CIRCLE_BUILD_URL"
elif [ -n "$TRAVIS" ]; then
	BRANCH="$TRAVIS_BRANCH"
	REPO_SLUG="$TRAVIS_REPO_SLUG"
	COMMIT_SHA="$TRAVIS_COMMIT"
	SRC_DIR="$TRAVIS_BUILD_DIR"
	BUILD_URL="$TRAVIS_BUILD_WEB_URL"
elif [ -n "$GITHUB_ACTIONS" ]; then
	BRANCH="$GITHUB_REF_NAME"
	REPO_SLUG="$GITHUB_REPOSITORY"
	COMMIT_SHA="$GITHUB_SHA"
	SRC_DIR="$GITHUB_WORKSPACE"
	BUILD_URL="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}/actions/runs/${GITHUB_RUN_ID}"
	REPO_SSH_URL="${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git"
else
	echo "Unknown CI environment, exiting."
	exit 1
fi

BUILD_DIR="/tmp/vip-go-build-$(date +%s)"
REPO_SSH_URL="${REPO_SSH_URL:-"git@github.com:${REPO_SLUG}"}"
DEPLOY_BRANCH="${BRANCH}${DEPLOY_SUFFIX}"
cd "$SRC_DIR"
COMMIT_AUTHOR_NAME="$( git log --format=%an -n 1 "${COMMIT_SHA}" )"
COMMIT_AUTHOR_EMAIL="$( git log --format=%ae -n 1 "${COMMIT_SHA}" )"
COMMIT_COMMITTER_NAME="$( git log --format=%cn -n 1 "${COMMIT_SHA}" )"
COMMIT_COMMITTER_EMAIL="$( git log --format=%ce -n 1 "${COMMIT_SHA}" )"


# Run some checks
# ---------------

if [ -n "$TRAVIS" ] && [ -n "$CIRCLECI" ] && [ -n "$GITHUB_ACTIONS" ]; then
	echo "ERROR: this script requires either CircleCI, Travis CI, or GitHub Actions"
	echo "You will need to amend the setup above to set the required variables from the information specific to your CI service or tool."
	exit 1
fi

if [ -z "${BRANCH}" ]; then
	echo "ERROR: No branch specified!"
	echo "This variable should be set by Travis CI, CircleCI, and GitHub Actions; if you consistently experience errors please check with WordPress.com VIP support."
	exit 1
fi

if [ -d "$BUILD_DIR" ]; then
	echo "ERROR: ${BUILD_DIR} already exists."
	echo "This should not happen, if you consistently experience errors please check with WordPress.com VIP support."
	exit 1
fi

if [[ "${BRANCH}" == *${DEPLOY_SUFFIX} ]]; then
	echo "NOTICE: Attempting to build from branch '${BRANCH}' to deploy '${DEPLOY_BRANCH}', seems like recursion so aborting."
	echo "This is a protective measure, no action is required."
	exit 0
fi

if [[ -n $TRAVIS ]] && [ "$TRAVIS_PULL_REQUEST" != 'false' ]; then
	echo "NOTICE: Aborting a build to '${DEPLOY_BRANCH}' from a pull request on '${BRANCH}', only build from merges directly to the branch"
	echo "This is a protective measure, no action is required."
	exit 0
fi

# Everything seems OK, getting the built repo sorted
# --------------------------------------------------

echo "Deploying ${BRANCH} to ${DEPLOY_BRANCH}"

# Making the directory we're going to sync the build into
git init "${BUILD_DIR}"
cd "${BUILD_DIR}"

if [ -n "${GITHUB_AUTH_TOKEN}" ]; then
	git config --local http.https://github.com/.extraheader "Authorization: basic ${GITHUB_AUTH_TOKEN}"
fi

git remote add origin "${REPO_SSH_URL}"
if [[ 0 = $(git ls-remote --heads "${REPO_SSH_URL}" "${DEPLOY_BRANCH}" | wc -l) ]]; then
	echo -e "\nCreating a ${DEPLOY_BRANCH} branch..."
	git checkout --quiet --orphan "${DEPLOY_BRANCH}"
else
	echo "Using existing ${DEPLOY_BRANCH} branch"
	git fetch origin "${DEPLOY_BRANCH}" --depth=1
	git checkout --quiet "${DEPLOY_BRANCH}"
fi

# Expand all submodules
git submodule update --init --recursive;

# Copy the files over
# -------------------

if ! command -v 'rsync'; then
	APT_GET_PREFIX=''
	if command -v 'sudo'; then
		APT_GET_PREFIX='sudo'
	fi

	$APT_GET_PREFIX apt-get update
	$APT_GET_PREFIX apt-get install -q -y rsync
fi

echo "Syncing files... quietly"

rsync --delete -a "${SRC_DIR}/" "${BUILD_DIR}" --exclude='.git/'

# gitignore override
# To allow commiting built files in the build branch (which are typically ignored)
# -------------------

BUILD_DEPLOYIGNORE_PATH="${BUILD_DIR}/.deployignore"
if [ -f "$BUILD_DEPLOYIGNORE_PATH" ]; then
	BUILD_GITIGNORE_PATH="${BUILD_DIR}/.gitignore"

	if [ -f "$BUILD_GITIGNORE_PATH" ]; then
		rm "$BUILD_GITIGNORE_PATH"
	fi

	echo "-- found .deployignore; emptying all gitignore files"
	find "$BUILD_DIR" -type f -name '.gitignore' | while read GITIGNORE_FILE; do
		echo "# Emptied by vip-go-build; '.deployignore' exists and used as global .gitignore. See https://wp.me/p9nvA-89A" > "$GITIGNORE_FILE"
		echo "${GITIGNORE_FILE}"
	done

	echo "-- using .deployignore as global .gitignore"
	mv "$BUILD_DEPLOYIGNORE_PATH" "$BUILD_GITIGNORE_PATH"
fi

# Make up the commit, commit, and push
# ------------------------------------

# Set Git committer
git config user.name "${COMMIT_COMMITTER_NAME}"
git config user.email "${COMMIT_COMMITTER_EMAIL}"

# Add changed files, delete deleted, etc, etc, you know the drill
git add -A .

if [ -z "$(git status --porcelain)" ]; then
	echo "NOTICE: No changes to deploy"
	exit 0
fi

# Commit it.
MESSAGE=$( printf 'Build changes from %s\n\n%s' "${COMMIT_SHA}" "${BUILD_URL}" )
# Set the Author to the commit (expected to be a client dev) and the committer
# will be set to the default Git user for this CI system
git commit --author="${COMMIT_AUTHOR_NAME} <${COMMIT_AUTHOR_EMAIL}>" -m "${MESSAGE}"

# Push it (push it real good).
git push origin "${DEPLOY_BRANCH}"