#include "FileFrecencyProvider.h"

#include <QHash>
#include <QMutexLocker>

#include "FrecencyStore.h"
#include "RepoFileIndex.h"
#include "RepoFileRows.h"

FileFrecencyProvider::FileFrecencyProvider(QObject* parent)
    : FuzzyRowProvider(parent)
{
}

void FileFrecencyProvider::setRoot(const QString& root)
{
  if (m_root == root) {
    return;
  }
  {
    const QMutexLocker locker(&inputLock());
    m_root = root;
  }
  emit rootChanged();
  invalidate();
}

void FileFrecencyProvider::setBackend(const QString& backend)
{
  if (m_backend == backend) {
    return;
  }
  {
    const QMutexLocker locker(&inputLock());
    m_backend = backend;
  }
  emit backendChanged();
  invalidate();
}

void FileFrecencyProvider::setIncludeTerminalRow(bool include)
{
  if (m_includeTerminalRow == include) {
    return;
  }
  {
    const QMutexLocker locker(&inputLock());
    m_includeTerminalRow = include;
  }
  emit includeTerminalRowChanged();
  invalidate();
}

QVariantList FileFrecencyProvider::rowsForQuery(const QString& query)
{
  // Reached under inputLock(), so every input member is stable.
  const QString root = m_root;
  const bool includeTerminal = m_includeTerminalRow;
  const RepoBackend backend = repoBackendFromWord(m_backend);

  // A non-repo workspace has no version control list, so the chooser falls back
  // to the directory picker. An empty listing here stays silent.
  if (root.isEmpty() || backend == RepoBackend::None) {
    return {};
  }

  const RepoFileList listing = RepoFileIndex::cachedFiles(root, backend);
  // One lock and one copy for the whole query, never one lock per candidate.
  const QHash<QString, int> scores = FrecencyStore::instance().snapshot();
  const RepoRows ranked =
      rankRepoRows(listing.paths, root, query, includeTerminal,
                   [&scores](const QString& path) {
                     return scores.value(path, 0);
                   });

  // A listing that failed names its reason instead of the ranker's note.
  setNote(listing.error.isEmpty() ? ranked.note : listing.error);
  return ranked.rows;
}