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#pragma once

#include "symbolindexertaskqueueinterface.h"
#include "symbolindexertask.h"

#include <filepathid.h>
#include <taskschedulerinterface.h>

#include <utils/algorithm.h>
#include <utils/smallstringvector.h>

#include <functional>
#include <vector>

namespace Sqlite {
class TransactionInterface;
}

namespace ClangBackEnd {

class SymbolsCollectorInterface;
class SymbolStorageInterface;

class SymbolIndexerTaskQueue final : public SymbolIndexerTaskQueueInterface
{
public:
    using Task = SymbolIndexerTask::Callable;

    SymbolIndexerTaskQueue(TaskSchedulerInterface<Task> &symbolIndexerTaskScheduler)
        : m_symbolIndexerScheduler(symbolIndexerTaskScheduler)
    {}

    void addOrUpdateTasks(std::vector<SymbolIndexerTask> &&tasks)
    {
        auto merge = [] (SymbolIndexerTask &&first, SymbolIndexerTask &&second) {
            first.callable = std::move(second.callable);

            return std::move(first);
        };

        m_tasks = Utils::setUnionMerge<std::vector<SymbolIndexerTask>>(tasks, m_tasks, merge);
    }
    void removeTasks(const std::vector<int> &projectPartIds)
    {
        auto shouldBeRemoved = [&] (const SymbolIndexerTask& task) {
            return std::binary_search(projectPartIds.begin(), projectPartIds.end(), task.projectPartId);
        };

        auto newEnd = std::remove_if(m_tasks.begin(), m_tasks.end(), shouldBeRemoved);

        m_tasks.erase(newEnd, m_tasks.end());
    }

    const std::vector<SymbolIndexerTask> &tasks() const
    {
        return m_tasks;
    }

    void processEntries()
    {
        uint taskCount = m_symbolIndexerScheduler.freeSlots();

        auto newEnd = std::prev(m_tasks.end(), std::min<int>(int(taskCount), int(m_tasks.size())));
        m_symbolIndexerScheduler.addTasks({std::make_move_iterator(newEnd),
                                           std::make_move_iterator(m_tasks.end())});
        m_tasks.erase(newEnd, m_tasks.end());
    }
    void syncTasks();

private:
    std::vector<Utils::SmallString> m_projectPartIds;
    std::vector<SymbolIndexerTask> m_tasks;
    TaskSchedulerInterface<Task> &m_symbolIndexerScheduler;
};

} // namespace ClangBackEnd