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

enable_deb822_sources() {
    local file="$1"
    local tmp

    tmp="$(mktemp)"
    awk '
        /^Types:/ {
            if ($0 !~ /(^|[[:space:]])deb-src($|[[:space:]])/) {
                print $0 " deb-src"
                next
            }
        }
        { print }
    ' "$file" > "$tmp"
    cat "$tmp" > "$file"
    rm -f "$tmp"
}

enable_legacy_sources() {
    local file="$1"
    local output="$2"

    awk '
        /^[[:space:]]*deb[[:space:]]/ {
            line = $0
            sub(/^[[:space:]]*deb[[:space:]]+/, "deb-src ", line)
            print line
        }
    ' "$file" > "$output"
}

found_sources=0

for sources_file in /etc/apt/sources.list.d/*.sources; do
    if [[ -f "$sources_file" ]]; then
        found_sources=1
        enable_deb822_sources "$sources_file"
    fi
done

if [[ -f /etc/apt/sources.list ]]; then
    found_sources=1
    enable_legacy_sources /etc/apt/sources.list \
        /etc/apt/sources.list.d/codex-deb-src.list
fi

if [[ "$found_sources" -eq 0 ]]; then
    echo "No apt source list files were found under /etc/apt" >&2
    exit 1
fi