#include <filesystem>
#include <fstream>
#include <memory>

#include "Directory.h"

#include "WallpaperEngine/Assets/CAssetLoadException.h"

using namespace WallpaperEngine::FileSystem;
using namespace WallpaperEngine::FileSystem::Adapters;

ReadStreamSharedPtr DirectoryAdapter::open (const std::filesystem::path& path) const {
    auto finalpath = std::filesystem::canonical(this->basepath / path);

    if (finalpath.string ().find (this->basepath.string ()) != 0) {
        throw std::filesystem::filesystem_error ("Cannot find file", path, std::error_code ());
    }

    auto status = std::filesystem::status (finalpath);

    if (!std::filesystem::exists (finalpath)) {
        throw std::filesystem::filesystem_error ("Cannot find file", path, std::error_code ());
    }

    if (!std::filesystem::is_regular_file (status)) {
        throw std::filesystem::filesystem_error ("Expected file but found a directory", path, std::error_code ());
    }

    return std::make_shared <std::ifstream> (finalpath);
}

bool DirectoryAdapter::exists (const std::filesystem::path& path) const {
    try {
        auto finalpath = std::filesystem::canonical(this->basepath / path);

        if (finalpath.string ().find (this->basepath.string ()) != 0) {
            return false;
        }

        auto status = std::filesystem::status (finalpath);

        if (!std::filesystem::exists (finalpath)) {
            return false;
        }

        if (!std::filesystem::is_regular_file (status)) {
            return false;
        }

        return true;
    } catch (std::filesystem::filesystem_error&) {
        return false;
    }
}

std::filesystem::path DirectoryAdapter::realpath (const std::filesystem::path& path) const {
    auto finalpath = std::filesystem::canonical(this->basepath / path);

    if (finalpath.string ().find (this->basepath.string ()) != 0) {
        throw Assets::CAssetLoadException ("Cannot find file", path);
    }

    return finalpath;
}


bool DirectoryFactory::handlesMountpoint (const std::filesystem::path& path) const {
    auto finalpath = std::filesystem::canonical (path);
    auto status = std::filesystem::status (finalpath);

    return std::filesystem::exists (finalpath) && std::filesystem::is_directory (status);
}

AdapterSharedPtr DirectoryFactory::create (const std::filesystem::path& path) const {
    auto finalpath = std::filesystem::canonical (path);
    auto status = std::filesystem::status (finalpath);

    if (!std::filesystem::exists (finalpath)) {
        throw std::filesystem::filesystem_error ("Cannot find directory", path, std::error_code ());
    }

    if (!std::filesystem::is_directory (status)) {
        throw std::filesystem::filesystem_error ("Expected directory but found a file", path, std::error_code ());
    }

    return std::make_unique<DirectoryAdapter> (finalpath);
}