/*

 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#include <memory>

#include <algorithm>

#include <shlwapi.h>

#include "FileUtils.h"

#include "WinErrorHandling.h"

#include "Log.h"

// Needed by FileUtils::isDirectoryNotEmpty

#pragma comment(lib, "shlwapi")

namespace FileUtils {

namespace {

tstring reservedFilenameChars() {

    tstring buf;

    for (char charCode = 0; charCode < 32; ++charCode) {

        buf.append(1, charCode);

    }

    buf += _T("<>:\"|?*/\\");

    return buf;

}

} // namespace

bool isDirSeparator(const tstring::value_type c) {

    return (c == '/' || c == '\\');

}

bool isFileExists(const tstring &filePath) {

    return GetFileAttributes(filePath.c_str()) != INVALID_FILE_ATTRIBUTES;

}

namespace {

bool isDirectoryAttrs(const DWORD attrs) {

    return attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY) != 0;

}

} // namespace

bool isDirectory(const tstring &filePath) {

    return isDirectoryAttrs(GetFileAttributes(filePath.c_str()));

}

bool isDirectoryNotEmpty(const tstring &dirPath) {

    if (!isDirectory(dirPath)) {

        return false;

    }

    return FALSE == PathIsDirectoryEmpty(dirPath.c_str());

}

tstring dirname(const tstring &path)

{

    tstring::size_type pos = path.find_last_of(_T("\\/"));

    if (pos != tstring::npos) {

        pos = path.find_last_not_of(_T("\\/"), pos); // skip trailing slashes

    }

    return pos == tstring::npos ? tstring() : path.substr(0, pos + 1);

}

tstring basename(const tstring &path) {

    const tstring::size_type pos = path.find_last_of(_T("\\/"));

    if (pos == tstring::npos) {

        return path;

    }

    return path.substr(pos + 1);

}

tstring suffix(const tstring &path) {

    const tstring::size_type pos = path.rfind('.');

    if (pos == tstring::npos) {

        return tstring();

    }

    const tstring::size_type dirSepPos = path.find_first_of(_T("\\/"),

                                                            pos + 1);

    if (dirSepPos != tstring::npos) {

        return tstring();

    }

    // test for '/..' and '..' cases

    if (pos != 0 && path[pos - 1] == '.'

                            && (pos == 1 || isDirSeparator(path[pos - 2]))) {

        return tstring();

    }

    return path.substr(pos);

}

tstring combinePath(const tstring& parent, const tstring& child) {

    if (parent.empty()) {

        return child;

    }

    if (child.empty()) {

        return parent;

    }

    tstring parentWOSlash = removeTrailingSlash(parent);

    // also handle the case when child contains starting slash

    bool childHasSlash = isDirSeparator(child.front());

    tstring childWOSlash = childHasSlash ? child.substr(1) : child;

    return parentWOSlash + _T("\\") + childWOSlash;

}

tstring removeTrailingSlash(const tstring& path) {

    if (path.empty()) {

        return path;

    }

    tstring::const_reverse_iterator it = path.rbegin();

    tstring::const_reverse_iterator end = path.rend();

    while (it != end && isDirSeparator(*it)) {

        ++it;

    }

    return path.substr(0, end - it);

}

tstring normalizePath(tstring v) {

    std::replace(v.begin(), v.end(), '/', '\\');

    return tstrings::toLower(v);

}

namespace {

bool createNewFile(const tstring& path) {

    HANDLE h = CreateFile(path.c_str(), GENERIC_WRITE, 0, NULL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL, NULL);

    // if the file exists => h == INVALID_HANDLE_VALUE & GetLastError returns ERROR_FILE_EXISTS

    if (h != INVALID_HANDLE_VALUE) {

        CloseHandle(h);

        LOG_TRACE(tstrings::any() << "Created [" << path << "] file");

        return true;

    }

    return false;

}

} // namespace

tstring createTempFile(const tstring &prefix, const tstring &suffix, const tstring &path)

{

    const tstring invalidChars = reservedFilenameChars();

    if (prefix.find_first_of(invalidChars) != tstring::npos) {

        JP_THROW(tstrings::any() << "Illegal characters in prefix=" << prefix);

    }

    if (suffix.find_first_of(invalidChars) != tstring::npos) {

        JP_THROW(tstrings::any() << "Illegal characters in suffix=" << suffix);

    }

    int rnd = (int)GetTickCount();

    // do no more than 100 attempts

    for (int i=0; i<100; i++) {

        const tstring filePath = mkpath() << path << (prefix + (tstrings::any() << (rnd + i)).tstr() + suffix);

        if (createNewFile(filePath)) {

            return filePath;

        }

    }

    // 100 attempts failed

    JP_THROW(tstrings::any() << "createTempFile("  << prefix << ", "

                                                    << suffix << ", "

                                                    << path << ") failed");

}

tstring createTempDirectory(const tstring &prefix, const tstring &suffix, const tstring &basedir) {

    const tstring filePath = createTempFile(prefix, suffix, basedir);

    // delete the file and create directory with the same name

    deleteFile(filePath);

    createDirectory(filePath);

    return filePath;

}

tstring createUniqueFile(const tstring &prototype) {

    if (createNewFile(prototype)) {

        return prototype;

    }

    return createTempFile(replaceSuffix(basename(prototype)),

                                        suffix(prototype), dirname(prototype));

}

namespace {

void createDir(const tstring path, LPSECURITY_ATTRIBUTES saAttr, tstring_array* createdDirs=0) {

    if (CreateDirectory(path.c_str(), saAttr)) {

        LOG_TRACE(tstrings::any() << "Created [" << path << "] directory");

        if (createdDirs) {

            createdDirs->push_back(removeTrailingSlash(path));

        }

    } else {

        const DWORD createDirectoryErr = GetLastError();

        // if saAttr is specified, fail even if the directory exists

        if (saAttr != NULL || !isDirectory(path)) {

            JP_THROW(SysError(tstrings::any() << "CreateDirectory(" << path << ") failed",

                                    CreateDirectory, createDirectoryErr));

        }

    }

}

}

void createDirectory(const tstring &path, tstring_array* createdDirs) {

    const tstring dirPath = removeTrailingSlash(path) + _T("\\");

    tstring::size_type pos = dirPath.find_first_of(_T("\\/"));

    while (pos != tstring::npos) {

        const tstring subdirPath = dirPath.substr(0, pos + 1);

        createDir(subdirPath, NULL, createdDirs);

        pos = dirPath.find_first_of(_T("\\/"), pos + 1);

    }

}

void copyFile(const tstring& fromPath, const tstring& toPath, bool failIfExists) {

    createDirectory(dirname(toPath));

    if (!CopyFile(fromPath.c_str(), toPath.c_str(), (failIfExists ? TRUE : FALSE))) {

        JP_THROW(SysError(tstrings::any()

                    << "CopyFile(" << fromPath << ", " << toPath << ", "

                                    << failIfExists << ") failed", CopyFile));

    }

    LOG_TRACE(tstrings::any() << "Copied [" << fromPath << "] file to ["

                                                            << toPath << "]");

}

namespace {

void moveFileImpl(const tstring& fromPath, const tstring& toPath,

                                                                DWORD flags) {

    const bool isDir = isDirectory(fromPath);

    if (!MoveFileEx(fromPath.c_str(), toPath.empty() ? NULL : toPath.c_str(),

                                                                    flags)) {

        JP_THROW(SysError(tstrings::any() << "MoveFileEx(" << fromPath

                        << ", " << toPath << ", " << flags << ") failed",

                                                                MoveFileEx));

    }

    const bool onReboot = 0 != (flags & MOVEFILE_DELAY_UNTIL_REBOOT);

    const LPCTSTR label = isDir ? _T("folder") : _T("file");

    tstrings::any msg;

    if (!toPath.empty()) {

        if (onReboot) {

            msg << "Move";

        } else {

            msg << "Moved";

        }

        msg << " '" << fromPath << "' " << label << " to '" << toPath << "'";

    } else {

        if (onReboot) {

            msg << "Delete";

        } else {

            msg << "Deleted";

        }

        msg << " '" << fromPath << "' " << label;

    }

    if (onReboot) {

        msg << " on reboot";

    }

    LOG_TRACE(msg);

}

} // namespace

void moveFile(const tstring& fromPath, const tstring& toPath, bool failIfExists)

{

    createDirectory(dirname(toPath));

    DWORD flags = MOVEFILE_COPY_ALLOWED;

    if (!failIfExists) {

        flags |= MOVEFILE_REPLACE_EXISTING;

    }

    moveFileImpl(fromPath, toPath, flags);

}

void deleteFile(const tstring &path)

{

    if (!deleteFile(path, std::nothrow)) {

        JP_THROW(SysError(tstrings::any()

                        << "DeleteFile(" << path << ") failed", DeleteFile));

    }

}

namespace {

bool notFound(const DWORD status=GetLastError()) {

    return status == ERROR_FILE_NOT_FOUND || status == ERROR_PATH_NOT_FOUND;

}

bool deleteFileImpl(const std::nothrow_t &, const tstring &path) {

    const bool deleted = (DeleteFile(path.c_str()) != 0);

    if (deleted) {

        LOG_TRACE(tstrings::any() << "Deleted [" << path << "] file");

        return true;

    }

    return notFound();

}

} // namespace

bool deleteFile(const tstring &path, const std::nothrow_t &) throw()

{

    bool deleted = deleteFileImpl(std::nothrow, path);

    const DWORD status = GetLastError();

    if (!deleted && status == ERROR_ACCESS_DENIED) {

        DWORD attrs = GetFileAttributes(path.c_str());

        SetLastError(status);

        if (attrs == INVALID_FILE_ATTRIBUTES) {

            return false;

        }

        if (attrs & FILE_ATTRIBUTE_READONLY) {

            // DeleteFile() failed because file is R/O.

            // Remove R/O attribute and retry DeleteFile().

            attrs &= ~FILE_ATTRIBUTE_READONLY;

            if (SetFileAttributes(path.c_str(), attrs)) {

                LOG_TRACE(tstrings::any() << "Discarded R/O attribute from ["

                                                        << path << "] file");

                deleted = deleteFileImpl(std::nothrow, path);

            } else {

                LOG_WARNING(SysError(tstrings::any()

                            << "Failed to discard R/O attribute from ["

                            << path << "] file. File will not be deleted",

                            SetFileAttributes).what());

                SetLastError(status);

            }

        }

    }

    return deleted || notFound();

}

void deleteDirectory(const tstring &path)

{

    if (!deleteDirectory(path, std::nothrow)) {

        JP_THROW(SysError(tstrings::any()

                << "RemoveDirectory(" << path << ") failed", RemoveDirectory));

    }

}

bool deleteDirectory(const tstring &path, const std::nothrow_t &) throw()

{

    const bool deleted = (RemoveDirectory(path.c_str()) != 0);

    if (deleted) {

        LOG_TRACE(tstrings::any() << "Deleted [" << path << "] directory");

    }

    return deleted || notFound();

}

namespace {

class DeleteFilesCallback: public DirectoryCallback {

public:

    explicit DeleteFilesCallback(bool ff): failfast(ff), failed(false) {

    }

    virtual bool onFile(const tstring& path) {

        if (failfast) {

            deleteFile(path);

        } else {

            updateStatus(deleteFile(path, std::nothrow));

        }

        return true;

    }

    bool good() const {

        return !failed;

    }

protected:

    void updateStatus(bool success) {

        if (!success) {

            failed = true;

        }

    }

    const bool failfast;

private:

    bool failed;

};

class DeleteAllCallback: public DeleteFilesCallback {

public:

    explicit DeleteAllCallback(bool failfast): DeleteFilesCallback(failfast) {

    }

    virtual bool onDirectory(const tstring& path) {

        if (failfast) {

            deleteDirectoryRecursive(path);

        } else {

            updateStatus(deleteDirectoryRecursive(path, std::nothrow));

        }

        return true;

    }

};

class BatchDeleter {

    const tstring dirPath;

    bool recursive;

public:

    explicit BatchDeleter(const tstring& path): dirPath(path) {

        deleteSubdirs(false);

    }

    BatchDeleter& deleteSubdirs(bool v) {

        recursive = v;

        return *this;

    }

    void execute() const {

        if (!isFileExists(dirPath)) {

            return;

        }

        iterateDirectory(true /* fail fast */);

        if (recursive) {

            deleteDirectory(dirPath);

        }

    }

    bool execute(const std::nothrow_t&) const {

        if (!isFileExists(dirPath)) {

            return true;

        }

        if (!isDirectory(dirPath)) {

            return false;

        }

        JP_TRY;

        if (!iterateDirectory(false /* ignore errors */)) {

            return false;

        }

        if (recursive) {

            return deleteDirectory(dirPath, std::nothrow);

        }

        return true;

        JP_CATCH_ALL;

        return false;

    }

private:

    bool iterateDirectory(bool failfast) const {

        std::unique_ptr<DeleteFilesCallback> callback;

        if (recursive) {

            callback = std::unique_ptr<DeleteFilesCallback>(

                                            new DeleteAllCallback(failfast));

        } else {

            callback = std::unique_ptr<DeleteFilesCallback>(

                                            new DeleteFilesCallback(failfast));

        }

        FileUtils::iterateDirectory(dirPath, *callback);

        return callback->good();

    }

};

} // namespace

void deleteFilesInDirectory(const tstring &dirPath) {

    BatchDeleter(dirPath).execute();

}

bool deleteFilesInDirectory(const tstring &dirPath,

                                            const std::nothrow_t &) throw() {

    return BatchDeleter(dirPath).execute(std::nothrow);

}

void deleteDirectoryRecursive(const tstring &dirPath) {

    BatchDeleter(dirPath).deleteSubdirs(true).execute();

}

bool deleteDirectoryRecursive(const tstring &dirPath,

                                            const std::nothrow_t &) throw() {

    return BatchDeleter(dirPath).deleteSubdirs(true).execute(std::nothrow);

}

namespace {

struct FindFileDeleter {

    typedef HANDLE pointer;

    void operator()(HANDLE h) {

        if (h && h != INVALID_HANDLE_VALUE) {

            FindClose(h);

        }

    }

};

typedef std::unique_ptr<HANDLE, FindFileDeleter> UniqueFindFileHandle;

}; // namesace

void iterateDirectory(const tstring &dirPath, DirectoryCallback& callback)

{

    const tstring searchString = combinePath(dirPath, _T("*"));

    WIN32_FIND_DATA findData;

    UniqueFindFileHandle h(FindFirstFile(searchString.c_str(), &findData));

    if (h.get() == INVALID_HANDLE_VALUE) {

        // GetLastError() == ERROR_FILE_NOT_FOUND is OK - no files in the directory