#include "Cookies.hpp"

#include <cstdio>

namespace molo::example::fw {

namespace {

unsigned long long fnv1a(const std::string& s) {
  unsigned long long h = 1469598103934665603ULL;
  for (unsigned char c : s) {
    h ^= c;
    h *= 1099511628211ULL;
  }
  return h;
}

}  // namespace

std::string cookie_sign(const std::string& value, const std::string& secret) {
  char buf[32];
  std::snprintf(buf, sizeof(buf), "%016llx",
                (unsigned long long)fnv1a(secret + "|" + value));
  return value + "." + buf;
}

bool cookie_verify(const std::string& signed_value, const std::string& secret,
                   std::string& out_value) {
  std::size_t dot = signed_value.rfind('.');
  if (dot == std::string::npos) return false;
  std::string value = signed_value.substr(0, dot);
  return cookie_sign(value, secret) == signed_value
             ? (out_value = value, true)
             : false;
}

std::string make_set_cookie(const std::string& name, const std::string& value,
                            const std::string& path, bool http_only,
                            bool secure, const std::string& same_site,
                            long max_age) {
  std::string out = name + "=" + value + "; Path=" + path;
  if (max_age >= 0) out += "; Max-Age=" + std::to_string(max_age);
  if (http_only) out += "; HttpOnly";
  if (secure) out += "; Secure";
  out += "; SameSite=" + same_site;
  return out;
}

}  // namespace molo::example::fw