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

repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
temp_dir="$(mktemp -d)"
trap 'rm -rf "$temp_dir"' EXIT

go_license="$(go env GOROOT)/LICENSE"
if [ ! -f "$go_license" ] && [ -f /usr/share/licenses/go/LICENSE ]; then
  go_license=/usr/share/licenses/go/LICENSE
fi
if [ ! -f "$go_license" ]; then
  echo "Go license file was not found" >&2
  exit 1
fi

cat >"$temp_dir/template.txt" <<'EOF'
{{ range . }}================================================================================
Package: {{ .Name }}
License: {{ .LicenseName }}
Source: {{ .LicenseURL }}

{{ .LicenseText }}
{{ end }}
EOF

{
  cat <<'EOF'
THIRD-PARTY SOFTWARE NOTICES

This file contains license notices for third-party software included in the distributed binary.

================================================================================
Package: Go standard library
License: BSD-3-Clause
Source: https://go.dev/LICENSE

EOF
  cat "$go_license"
  printf '\n'
  cd "$repo_root"
  go run github.com/google/go-licenses/v2@v2.0.1 report ./cmd/dataxl \
    --ignore=git.rumginger.org/agent/dataxl \
    --template="$temp_dir/template.txt"
} >"$temp_dir/THIRD_PARTY_LICENSES.txt"

awk '
  { lines[NR] = $0 }
  $0 !~ /^[[:space:]]*$/ { last_content_line = NR }
  END {
    for (line_number = 1; line_number <= last_content_line; line_number++) {
      print lines[line_number]
    }
  }
' "$temp_dir/THIRD_PARTY_LICENSES.txt" >"$temp_dir/THIRD_PARTY_LICENSES.normalized.txt"

mv "$temp_dir/THIRD_PARTY_LICENSES.normalized.txt" "$repo_root/THIRD_PARTY_LICENSES.txt"