#!/bin/sh

package_size_table() {
	packages=$(nix flake show --json 2>/dev/null | jq --raw-output '.packages."x86_64-linux" | ".#" + keys[]')
	# we want to split the words as each of them is a different installable
	# shellcheck disable=SC2086
	nix build $packages
	# shellcheck disable=SC2086
	table=$(nix path-info --size --closure-size --human-readable \
		$packages |
		sed 's/^\(\S\+\)\(\s\+\)\(\S\+\)\(\s\+\)\(\S\+\)$/| \1\2| \3 | \4\5 |/')

	cat <<-EOF
		| Nix Store Path | NAR Size | Closure Size |
		|----------------|---------:|-------------:|
		$table
	EOF
}

if [ "$CI" = "true" ]; then
	pr_number=$(curl -X 'GET' \
		"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/pulls?state=open&sort=recentupdate" \
		-H 'accept: application/json' |
		jq --arg head_ref "$GITHUB_HEAD_REF" '.[] | select(.head.ref == $head_ref) | .number')
	echo "Retrieved index: $pr_number"
	echo "Expected PR URL: $GITHUB_SERVER_URL/$GITHUB_REPOSITORY/pulls/$pr_number"
	echo 'Generating comment body'
	comment=$(
		cat <<-EOF
			### NixOS Configurations sizes

			TODO

			### Package sizes

			$(package_size_table)
		EOF
	)
	echo 'Posting comment:'
	echo "$comment"
	echo 'Request data:'
	data=$(echo '{}' | jq --arg comment "$comment" '.body=$comment')
	echo "$data"
	curl -o - -v -X 'POST' \
		"$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/issues/$pr_number/comments?token=$GITHUB_TOKEN" \
		-H 'accept: application/json' \
		-d "$data"
else
	package_size_table
fi