#!/usr/bin/env bash
#
# @license Apache-2.0
#
# Copyright (c) 2021 The Stdlib Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# shellcheck disable=SC2181

# Publishes a new version of the project to the npm package registry.
#
# A `release` argument must be one of the following:
#
# -   `patch`
# -   `minor`
# -   `major`
# -   `premajor`
# -   `preminor`
# -   `prepatch`
# -   `prerelease`
#
# Usage: npm_publish <release> <message>
#
# Arguments:
#
#   release     release type.
#   message     commit message.
#

# VARIABLES #

# Set the release type:
release="$1"

# Set the release commit message:
message="$2"

# Determine the root directory:
root_dir="$(git rev-parse --show-toplevel)"

# Get the current commit hash:
git_hash="$(git rev-parse HEAD)"

# Get the current Git branch:
git_branch="$(git rev-parse --abbrev-ref HEAD)"

# Specify the path to the root package.json:
package_json="${root_dir}/package.json"

# Get the current project version:
script1="var pkg = require( '${package_json}' ); console.log( pkg.version );"
current_version=$(node -e "${script1}" | tr -d '\n' )

# Determine the new project version:
script2="var semver = require( 'semver' ); console.log( semver.inc( '${current_version}', '${release}' ) );"
release_version=$(node -e "${script2}" | tr -d '\n' )

# Specify the project source code directory:
base_dir="${root_dir}/lib/node_modules"

# Specify the path to a script for updating package directories meta data:
update_directories="${base_dir}/@stdlib/_tools/package-json/scripts/update_directories"

# Specify the output build directory when generating a gzipped archive:
npm_tarball_build_out="${root_dir}/build/npm"

# Define the gzipped archive basename:
npm_tarball_basename="stdlib-stdlib-${release_version}.tgz"


# FUNCTIONS #

# Error handler.
#
# $1 - error status
on_error() {
	cleanup
	exit "$1"
}

# Runs clean-up tasks.
cleanup() {
	rm -rf "${npm_tarball_build_out}"

}

# Prints a success message.
print_success() {
	echo '' >&2
	echo 'Success!' >&2
	echo '' >&2
}

# Prints usage information.
usage() {
	echo '' >&2
	echo 'Usage: npm_publish <release> <message>' >&2
	echo '' >&2
	echo 'Arguments:' >&2
	echo '' >&2
	echo '  release     release type (patch, minor, major, etc).' >&2
	echo '  message     commit message.' >&2
	echo '' >&2
}

# Reverts changes, resetting repository to its prior state.
revert_changes() {
	echo 'Reverting changes...' >&2
	git reset --hard "${git_hash}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when attempting to reverting changes.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully reverted changes.' >&2
	echo '' >&2
	return 0
}

# Performs checks to prevent unintended behavior when attempting to publish to npm.
check() {
	echo 'Performing checks...' >&2
	if [[ "${git_branch}" != 'develop' ]]; then
		echo '' >&2
		echo 'Error: invalid operation. Releasing new versions should only be performed on the develop branch.' >&2
		echo '' >&2
		return 1
	fi
	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Error: invalid operation. Working directory must be clean.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully performed checks.' >&2
	echo '' >&2
	return 0
}

# Pulls the latest changes from a remote repository.
update_repository() {
	echo 'Pulling the latest changes...' >&2
	git pull origin "${git_branch}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Pulling the latest changes failed. Check for merge conflicts.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully pulled latest changes.' >&2
	echo '' >&2
	return 0
}

# Initializes the development environment.
init() {
	echo 'Initializing development environment...' >&2
	make init
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Unable to initialize development environment.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully initialized development environment.' >&2
	echo '' >&2
	return 0
}

# Checks licenses of dependencies.
check_licenses() {
	echo 'Checking dependency licenses...' >&2
	make check-licenses-production >/dev/null
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Potential incompatible dependency license. Please resolve before publishing. Command: make check-licenses-production.' >&2
		echo '' >&2
		return 1
	fi
	echo 'No detected licensing issues.' >&2
	echo '' >&2
	return 0
}

# Updates package meta data.
update_package_meta_data() {
	echo 'Updating package meta data...' >&2

	echo '' >&2
	echo 'Updating directories...' >&2
	node "${update_directories}" "${base_dir}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating directories meta data.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully updated directories.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m 'Update directories meta data'
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2

	return 0
}

# Updates namespace table of contents.
update_namespace_tocs() {
	local files

	echo 'Updating namespace table of contents...' >&2

	echo '' >&2
	echo 'Resolving list of namespace READMEs...' >&2
	files=$(make list-pkgs-namespace-readmes | tr '\n' ' ')
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when resolving a list of namespace READMEs.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully resolved namespace READMEs.' >&2

	echo '' >&2
	echo 'Updating READMEs...' >&2
	make FILES="${files}" markdown-namespace-tocs-files
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating namespace README table of contents.' >&2
		echo '' >&2
		return 1
	fi
	make FILES="${files}" markdown-pkg-urls-files
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating namespace README package URLs.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully updated READMEs.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m 'Update namespace ToCs'
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2

	return 0
}

# Updates package URLs in Markdown files.
update_markdown_package_urls() {
	echo 'Updating package URLs in Markdown files...' >&2
	make markdown-pkg-urls MARKDOWN_FILTER='.*/lib/node_modules/@stdlib/.*'
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating package URLs in Markdown files.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully updated Markdown files.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m 'Update package URLs'
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2

	return 0
}

# Updates REPL documentation.
update_repl_docs() {
	echo 'Updating REPL documentation...' >&2
	make repl-docs
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating REPL documentation.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully updated REPL documentation.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m 'Update REPL docs'
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2

	return 0
}

# Updates the version in the root package.json.
update_version() {
	echo 'Updating project version...' >&2
	echo "Current version: ${current_version}" >&2
	echo "Release version: ${release_version}" >&2
	sed -i '' "s/${current_version}/${release_version}/" "${package_json}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when updating project version.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully updated version.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m "${message}"
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2
	return 0
}

# Generates and publishes distributable bundles.
publish_bundles() {
	echo 'Publishing distributable bundles...' >&2
	make dist-bundles-publish
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when attempting to publish distributable bundles.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully published distributable bundles.' >&2

	echo '' >&2
	echo 'Removing bundle artifacts...' >&2
	make clean-dist-bundles
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when attempting to remove bundle artifacts.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully removed bundled artifacts.' >&2

	if [[ -n "$(git status --porcelain)" ]]; then
		echo '' >&2
		echo 'Committing changes...' >&2
		git add -A && git commit -m 'Update dist versions'
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Unable to commit changes.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully committed changes.' >&2
	fi
	echo '' >&2

	return 0
}

# Creates (and pushes) a new Git tag.
create_tag() {
	echo 'Creating a new tag...' >&2
	git tag -a "v${release_version}" -m "${message}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when attempting to create a new tag.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully created tag.' >&2
	echo '' >&2
	return 0
}

# Generates a gzipped archive for publishing to npm.
create_tarball() {
	echo 'Generating a gzipped archive for publishing to npm...' >&2

	mkdir -p "${npm_tarball_build_out}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Unable to create output build directory.' >&2
		echo '' >&2
		return 1
	fi
	npm pack "${root_dir}" >/dev/null
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Unable to create a gzipped archive.' >&2
		echo '' >&2
		return 1
	fi
	mv "${root_dir}/${npm_tarball_basename}" "${npm_tarball_build_out}/${npm_tarball_basename}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Unable to move gzipped archive to build directory.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully generated a gzipped archive.' >&2
	echo '' >&2

	return 0
}

# Publishes a tarball to the npm package registry.
publish() {
	echo 'Publishing tarball to npm...' >&2
	npm publish "${npm_tarball_build_out}/${npm_tarball_basename}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Unable to publish to npm.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully published to npm.' >&2
	echo '' >&2
	return 0
}

# Updates a remote repository.
update_remote_repository() {
	echo 'Pushing tags to remote repository...' >&2
	git push origin "v${release_version}"
	if [[ "$?" -ne 0 ]]; then
		echo '' >&2
		echo 'Error: unexpected error. Encountered an error when attempting to push tags to remote repository.' >&2
		echo '' >&2
		return 1
	fi
	echo 'Successfully pushed tags.' >&2

	echo '' >&2
	echo 'Pushing commits to remote repository...' >&2
	git push origin "${git_branch}"
	if [[ "$?" -ne 0 ]]; then
		echo 'Failed to push commits. Pulling down any recent changes...' >&2
		git pull origin "${git_branch}"
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Pulling the latest changes failed. Check for merge conflicts.' >&2
			echo '' >&2
			return 1
		fi
		echo 'Successfully pulled latest changes.' >&2

		git push origin "${git_branch}"
		if [[ "$?" -ne 0 ]]; then
			echo '' >&2
			echo 'Error: unexpected error. Encountered an error when attempting to push commits to remote repository.' >&2
			echo '' >&2
			return 1
		fi
	fi
	echo 'Successfully pushed commits.' >&2
	echo '' >&2

	return 0
}


# MAIN #

# Main execution sequence.
main() {
	echo '' >&2
	check
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	update_repository
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	init
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	check_licenses
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	update_package_meta_data
	if [[ "$?" -ne 0 ]]; then
		revert_changes
		on_error 1
	fi
	update_namespace_tocs
	if [[ "$?" -ne 0 ]]; then
		revert_changes
		on_error 1
	fi
	update_markdown_package_urls
	if [[ "$?" -ne 0 ]]; then
		revert_changes
		on_error 1
	fi
	update_repl_docs
	if [[ "$?" -ne 0 ]]; then
		revert_changes
		on_error 1
	fi
	update_version
	if [[ "$?" -ne 0 ]]; then
		revert_changes
		on_error 1
	fi

	# WARNING: at this point, we are at the point of no return and, from this point forward, cannot easily revert changes to the local repository as packages may already be published...

	publish_bundles
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	create_tag
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	create_tarball
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	publish
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	update_remote_repository
	if [[ "$?" -ne 0 ]]; then
		on_error 1
	fi
	print_success
	cleanup
	exit 0
}

# Handle arguments...
if [[ "$#" -eq 0 ]]; then
	usage
	exit 0
elif [[ "$#" -gt 2 ]]; then
	echo '' >&2
	echo 'Error: unrecognized arguments. Must specify a version and message.' >&2
	echo '' >&2
	exit 1
fi

# Run main:
main