Standard-of-Iron/utils/resource_utils.h

#pragma once

#include <QCoreApplication>
#include <QDir>
#include <QFileInfo>
#include <QString>
#include <QStringList>

namespace Utils::Resources {

// Resolve resources that may have been relocated under a Qt QML module prefix.
inline auto resolveResourcePath(const QString &path) -> QString {
  if (path.isEmpty()) {
    return path;
  }

  const bool is_resource = path.startsWith(QStringLiteral(":/"));
  const QString relative = is_resource ? path.mid(2) : QString{};

  auto exists = [](const QString &candidate) {
    QFileInfo const info(candidate);
    if (info.exists()) {
      return true;
    }
    QDir const dir(candidate);
    return dir.exists();
  };

  // For Qt resource paths, prefer a filesystem override when available so live
  // shader edits are picked up without rebuilding the resource bundle.
  if (is_resource) {
    auto search_upwards = [&](const QString &startDir) -> QString {
      if (startDir.isEmpty()) {
        return {};
      }
      QDir dir(startDir);
      for (int i = 0; i < 5; ++i) {
        QString candidate = dir.filePath(relative);
        if (exists(candidate)) {
          return candidate;
        }
        if (!dir.cdUp()) {
          break;
        }
      }
      return {};
    };

    if (QString candidate =
            search_upwards(QCoreApplication::applicationDirPath());
        !candidate.isEmpty()) {
      return candidate;
    }
    if (QString candidate = search_upwards(QDir::currentPath());
        !candidate.isEmpty()) {
      return candidate;
    }
  }

  if (exists(path)) {
    return path;
  }

  if (!is_resource) {
    return path;
  }

  static const QStringList kAlternateRoots = {
      QStringLiteral(":/StandardOfIron"),
      QStringLiteral(":/qt/qml/StandardOfIron"),
      QStringLiteral(":/qt/qml/default")};

  for (const auto &root : kAlternateRoots) {
    QString candidate = root;
    if (!candidate.endsWith('/')) {
      candidate.append('/');
    }
    candidate.append(relative);
    if (exists(candidate)) {
      return candidate;
    }
  }

  return path;
}

} // namespace Utils::Resources