/*
 * Copyright (C) by Christian Kamm <mail@ckamm.de>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 */

#include "localdiscoverytracker.h"

#include "syncfileitem.h"

#include <QLoggingCategory>

using namespace OCC;

Q_LOGGING_CATEGORY(lcLocalDiscoveryTracker, "sync.localdiscoverytracker", QtInfoMsg)

LocalDiscoveryTracker::LocalDiscoveryTracker()
{
}

void LocalDiscoveryTracker::addTouchedPath(const QString &relativePath)
{
    qCDebug(lcLocalDiscoveryTracker) << u"inserted touched" << relativePath;
    _localDiscoveryPaths.insert(relativePath);
}

void LocalDiscoveryTracker::startSyncFullDiscovery()
{
    _localDiscoveryPaths.clear();
    _previousLocalDiscoveryPaths.clear();
    qCDebug(lcLocalDiscoveryTracker) << u"full discovery";
}

void LocalDiscoveryTracker::startSyncPartialDiscovery()
{
    if (lcLocalDiscoveryTracker().isDebugEnabled()) {
        QStringList paths;
        for (auto &path : _localDiscoveryPaths)
            paths.append(path);
        qCDebug(lcLocalDiscoveryTracker) << u"partial discovery with paths: " << paths;
    }

    _previousLocalDiscoveryPaths = std::move(_localDiscoveryPaths);
    _localDiscoveryPaths.clear();
}

const std::set<QString> &LocalDiscoveryTracker::localDiscoveryPaths() const
{
    return _localDiscoveryPaths;
}

void LocalDiscoveryTracker::slotItemCompleted(const SyncFileItemPtr &item)
{
    // For successes, we want to wipe the file from the list to ensure we don't
    // rediscover it even if this overall sync fails.
    //
    // For failures, we want to add the file to the list so the next sync
    // will be able to retry it.

    switch (item->_status) {
    case SyncFileItem::NoStatus:
        // we can't use the flags operator with CSYNC_INSTRUCTION_NONE
        if (item->instruction() & ~(CSYNC_INSTRUCTION_NONE | CSYNC_INSTRUCTION_UPDATE_METADATA)) {
            break;
        }
        Q_FALLTHROUGH();
    case SyncFileItem::Success:
        Q_FALLTHROUGH();
    case SyncFileItem::FileIgnored:
        Q_FALLTHROUGH();
    case SyncFileItem::Restoration:
        Q_FALLTHROUGH();
    case SyncFileItem::Conflict:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::Message:
        if (_previousLocalDiscoveryPaths.erase(item->localName())) {
            qCDebug(lcLocalDiscoveryTracker) << u"wiped successful item" << item->localName();
        }
        if (!item->_renameTarget.isEmpty() && _previousLocalDiscoveryPaths.erase(item->_renameTarget)) {
            qCDebug(lcLocalDiscoveryTracker) << u"wiped successful item" << item->_renameTarget;
        }
        return;
    case OCC::SyncFileItem::FatalError:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::NormalError:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::SoftError:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::DetailError:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::BlacklistedError:
        Q_FALLTHROUGH();
    case OCC::SyncFileItem::Excluded:
        [[fallthrough]];
    case OCC::SyncFileItem::FilenameReserved:
        break;
    case SyncFileItem::StatusCount:
        Q_UNREACHABLE();
    }

    _localDiscoveryPaths.insert(item->localName());
    qCDebug(lcLocalDiscoveryTracker) << u"inserted error item" << item->localName();
}

void LocalDiscoveryTracker::slotSyncFinished(bool success)
{
    if (success) {
        qCDebug(lcLocalDiscoveryTracker) << u"sync success, forgetting last sync's local discovery path list";
    } else {
        // On overall-failure we can't forget about last sync's local discovery
        // paths yet, reuse them for the next sync again.
        // C++17: Could use std::set::merge().
        _localDiscoveryPaths.insert(
            _previousLocalDiscoveryPaths.begin(), _previousLocalDiscoveryPaths.end());
        qCDebug(lcLocalDiscoveryTracker) << u"sync failed, keeping last sync's local discovery path list";
    }
    _previousLocalDiscoveryPaths.clear();
}
