#!/usr/bin/env bash
set -ueo pipefail

COMMIT=${1-HEAD}

commit=$(git show -s --no-notes "$COMMIT")
echo "$commit"
if grep -q '^\s*Builds-required: none$' <<<"$commit"; then
	echo '---'
	echo '`Builds-required: none` in commit message, skipping commit'
	exit 0
fi
echo '---'

if grep -q '^\s*Builds-required: ' <<<"$commit"; then
	verification_line=$(grep '^\s*Builds-required:' <<<"$commit")
	verspec=$(sed 's|^\s*Builds-required:||' <<<"$verification_line")
	if ! grep -Eq '^ make=[0-9]+ raw=[0-9]+ nix=[0-9]+$' <<<"$verspec"; then
		echo 'Malformed `Builds-required:` line' >&2
		exit 7
	fi
	required_make=$(sed -E 's|.* make=([0-9]+).*|\1|' <<<"$verspec")
	(( required_make >= 0 ))
	required_raw=$(sed -E 's|.* raw=([0-9]+).*|\1|' <<<"$verspec")
	(( required_raw >= 0 ))
	required_nix=$(sed -E 's|.* nix=([0-9]+).*|\1|' <<<"$verspec")
	(( required_nix >= 0 ))
else
	required_make=2
	required_raw=1
	required_nix=2
fi

git fetch origin refs/notes/commits:refs/notes/commits
notes=$(git notes show "$COMMIT" \
	| grep ^Built-on: \
	| grep -v USE_CCACHE \
	| sort -u)
using_make=$(grep -Fw how=make <<<"$notes" | wc -l) || true
using_raw=$(grep -Fw how=raw <<<"$notes" | wc -l) || true
using_nix=$(grep -Fw how=nix <<<"$notes" | wc -l) || true
echo "$notes"

status=true
text=""
if (( using_make < required_make )); then
	text+="Not enough how=make commits: $using_make < $required_make\n"
	status=false
fi
if (( using_raw < required_raw )); then
	text+="Not enough how=raw commits: $using_raw < $required_raw\n"
	status=false
fi
if (( using_nix < required_nix )); then
	text+="Not enough how=nix commits: $using_nix < $required_nix\n"
	status=false
fi

echo '---'
echo "${using_make} out of ${required_make} required how=make builds"
echo "${using_raw} out of ${required_raw} required how=raw builds"
echo "${using_nix} out of ${required_nix} required how=nix builds"
if ! $status; then
	echo -ne "---\n$text"
fi
$status