/**
 * @file lldir.h
 * @brief Definition of directory utilities class
 *
 * $LicenseInfo:firstyear=2000&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#ifndef LL_LLDIR_H
#define LL_LLDIR_H

// these numbers are read from settings_files.xml, so we need to be explicit
typedef enum ELLPath
{
    LL_PATH_NONE = 0,
    LL_PATH_USER_SETTINGS = 1,
    LL_PATH_APP_SETTINGS = 2,
    LL_PATH_PER_SL_ACCOUNT = 3, // returns/expands to blank string if we don't know the account name yet
    LL_PATH_CACHE = 4,
    LL_PATH_CHARACTER = 5,
    LL_PATH_HELP = 6,
    LL_PATH_LOGS = 7,
    LL_PATH_TEMP = 8,
    LL_PATH_SKINS = 9,
    LL_PATH_TOP_SKIN = 10,
    LL_PATH_CHAT_LOGS = 11,
    LL_PATH_PER_ACCOUNT_CHAT_LOGS = 12,
    LL_PATH_USER_SKIN = 14,
    LL_PATH_LOCAL_ASSETS = 15,
    LL_PATH_EXECUTABLE = 16,
    LL_PATH_DEFAULT_SKIN = 17,
    LL_PATH_FONTS = 18,
    LL_PATH_DUMP = 19,
    LL_PATH_LAST
} ELLPath;

/// Directory operations
class LLDir
{
 public:
    LLDir();
    virtual ~LLDir();

    // app_name - Usually SecondLife, used for creating settings directories
    // in OS-specific location, such as C:\Documents and Settings
    // app_read_only_data_dir - Usually the source code directory, used
    // for test applications to read newview data files.
    virtual void initAppDirs(const std::string &app_name,
        const std::string& app_read_only_data_dir = "") = 0;

    virtual S32 deleteFilesInDir(const std::string &dirname, const std::string &mask);
    U32 deleteDirAndContents(const std::string& dir_name);
    std::vector<std::string> getFilesInDir(const std::string &dirname);
// pure virtual functions
    virtual std::string getCurPath() = 0;
    virtual bool fileExists(const std::string &filename) const = 0;

    const std::string findFile(const std::string& filename, const std::vector<std::string> filenames) const;
    const std::string findFile(const std::string& filename, const std::string& searchPath1 = "", const std::string& searchPath2 = "", const std::string& searchPath3 = "") const;

    virtual std::string getLLPluginLauncher() = 0; // full path and name for the plugin shell
    virtual std::string getLLPluginFilename(std::string base_name) = 0; // full path and name to the plugin DSO for this base_name (i.e. 'FOO' -> '/bar/baz/libFOO.so')

    const std::string &getExecutablePathAndName() const;    // Full pathname of the executable
    const std::string &getAppName() const;          // install directory under progams/ ie "SecondLife"
    const std::string &getExecutableDir() const;    // Directory where the executable is located
    const std::string &getExecutableFilename() const;// Filename of .exe
    const std::string &getWorkingDir() const; // Current working directory
    const std::string &getAppRODataDir() const; // Location of read-only data files
    const std::string &getOSUserDir() const;        // Location of the os-specific user dir
    const std::string &getOSUserAppDir() const; // Location of the os-specific user app dir
    const std::string &getLindenUserDir() const;    // Location of the Linden user dir.
    const std::string &getChatLogsDir() const;  // Location of the chat logs dir.
    const std::string &getDumpDir() const;  // Location of the per-run dump dir.
    bool              dumpDirExists() const;
    const std::string &getPerAccountChatLogsDir() const;    // Location of the per account chat logs dir.
    const std::string &getTempDir() const;          // Common temporary directory
    const std::string  getCacheDir(bool get_default = false) const; // Location of the cache.
    const std::string &getOSCacheDir() const;       // location of OS-specific cache folder (may be empty string)
    const std::string &getCAFile() const;           // File containing TLS certificate authorities
    const std::string &getDirDelimiter() const; // directory separator for platform (ie. '\' or '/' or ':')
    const std::string &getDefaultSkinDir() const;   // folder for default skin. e.g. c:\program files\second life\skins\default
    const std::string &getSkinDir() const;      // User-specified skin folder.
    const std::string &getUserDefaultSkinDir() const; // dir with user modifications to default skin
    const std::string &getUserSkinDir() const;      // User-specified skin folder with user modifications. e.g. c:\documents and settings\username\application data\second life\skins\curskin
    const std::string getSkinBaseDir() const;       // folder that contains all installed skins (not user modifications). e.g. c:\program files\second life\skins
    const std::string &getLLPluginDir() const;      // Directory containing plugins and plugin shell
    const std::string &getUserName() const;

    // Expanded filename
    std::string getExpandedFilename(ELLPath location, const std::string &filename) const;
    std::string getExpandedFilename(ELLPath location, const std::string &subdir, const std::string &filename) const;
    std::string getExpandedFilename(ELLPath location, const std::string &subdir1, const std::string &subdir2, const std::string &filename) const;

    // Base and Directory name extraction
    std::string getBaseFileName(const std::string& filepath, bool strip_exten = false) const;
    std::string getDirName(const std::string& filepath) const;
    std::string getExtension(const std::string& filepath) const; // Excludes '.', e.g getExtension("foo.wav") == "wav"

    // these methods search the various skin paths for the specified file in the following order:
    // getUserSkinDir(), getUserDefaultSkinDir(), getSkinDir(), getDefaultSkinDir()
    /// param value for findSkinnedFilenames(), explained below
    enum ESkinConstraint { CURRENT_SKIN, ALL_SKINS };
    /**
     * Given a filename within skin, return an ordered sequence of paths to
     * search. Nonexistent files will be filtered out -- which means that the
     * vector might be empty.
     *
     * @param subdir Identify top-level skin subdirectory by passing one of
     * LLDir::XUI (file lives under "xui" subtree), LLDir::TEXTURES (file
     * lives under "textures" subtree), LLDir::SKINBASE (file lives at top
     * level of skin subdirectory).
     * @param filename Desired filename within subdir within skin, e.g.
     * "panel_login.xml". DO NOT prepend (e.g.) "xui" or the desired language.
     * @param constraint Callers perform two different kinds of processing.
     * When fetching a XUI file, for instance, the existence of @a filename in
     * the specified skin completely supercedes any @a filename in the default
     * skin. For that case, leave the default @a constraint=CURRENT_SKIN. The
     * returned vector will contain only
     * ".../<i>current_skin</i>/xui/en/<i>filename</i>",
     * ".../<i>current_skin</i>/xui/<i>current_language</i>/<i>filename</i>".
     * But for (e.g.) "strings.xml", we want a given skin to be able to
     * override only specific entries from the default skin. Any string not
     * defined in the specified skin will be sought in the default skin. For
     * that case, pass @a constraint=ALL_SKINS. The returned vector will
     * contain at least ".../default/xui/en/strings.xml",
     * ".../default/xui/<i>current_language</i>/strings.xml",
     * ".../<i>current_skin</i>/xui/en/strings.xml",
     * ".../<i>current_skin</i>/xui/<i>current_language</i>/strings.xml".
     */
    std::vector<std::string> findSkinnedFilenames(const std::string& subdir,
                                                  const std::string& filename,
                                                  ESkinConstraint constraint=CURRENT_SKIN) const;
    /// Values for findSkinnedFilenames(subdir) parameter
    static const char *XUI, *TEXTURES, *SKINBASE;
    /**
     * Return the base-language pathname from findSkinnedFilenames(), or
     * the empty string if no such file exists. Parameters are identical to
     * findSkinnedFilenames(). This is shorthand for capturing the vector
     * returned by findSkinnedFilenames(), checking for empty() and then
     * returning front().
     */
    std::string findSkinnedFilenameBaseLang(const std::string &subdir,
                                            const std::string &filename,
                                            ESkinConstraint constraint=CURRENT_SKIN) const;
    /**
     * Return the "most localized" pathname from findSkinnedFilenames(), or
     * the empty string if no such file exists. Parameters are identical to
     * findSkinnedFilenames(). This is shorthand for capturing the vector
     * returned by findSkinnedFilenames(), checking for empty() and then
     * returning back().
     */
    std::string findSkinnedFilename(const std::string &subdir,
                                    const std::string &filename,
                                    ESkinConstraint constraint=CURRENT_SKIN) const;

    // random filename in common temporary directory
    std::string getTempFilename() const;

    static std::string getDumpLogsDirPath(const std::string &file_name = "");

    // For producing safe download file names from potentially unsafe ones
    static std::string getScrubbedFileName(std::string_view uncleanFileName);
    static std::string getForbiddenFileChars();
    void setDumpDir( const std::string& path );


    virtual void setChatLogsDir(const std::string &path);       // Set the chat logs dir to this user's dir
    virtual void setPerAccountChatLogsDir(const std::string &username);     // Set the per user chat log directory.
    virtual void setLindenUserDir(const std::string &username);     // Set the linden user dir to this user's dir
    virtual void setSkinFolder(const std::string &skin_folder, const std::string& language);
    virtual std::string getSkinFolder() const;
    virtual std::string getLanguage() const;
    virtual bool setCacheDir(const std::string &path);
    virtual void updatePerAccountChatLogsDir();

    virtual void dumpCurrentDirectories(LLError::ELevel level = LLError::LEVEL_DEBUG);

    // Utility routine
    std::string buildSLOSCacheDir() const;

    /// Append specified @a name to @a destpath, separated by getDirDelimiter()
    /// if both are non-empty.
    void append(std::string& destpath, const std::string& name) const;
    /// Variadic form: append @a name0 and @a name1 and arbitrary other @a
    /// names to @a destpath, separated by getDirDelimiter() as needed.
    template <typename... NAMES>
    void append(std::string& destpath, const std::string& name0, const std::string& name1,
                const NAMES& ... names) const
    {
        // In a typical recursion case, we'd accept (destpath, name0, names).
        // We accept (destpath, name0, name1, names) because it's important to
        // delegate the two-argument case to the non-template implementation.
        append(destpath, name0);
        append(destpath, name1, names...);
    }

    /// Append specified @a names to @a path, separated by getDirDelimiter()
    /// as needed. Return result, leaving @a path unmodified.
    template <typename... NAMES>
    std::string add(const std::string& path, const NAMES& ... names) const
    {
        std::string destpath(path);
        append(destpath, names...);
        return destpath;
    }

protected:
    // Does an add() or append() call need a directory delimiter?
    typedef std::pair<bool, unsigned short> SepOff;
    SepOff needSep(const std::string& path, const std::string& name) const;
    // build mSearchSkinDirs without adding duplicates
    void addSearchSkinDir(const std::string& skindir);

    // Internal to findSkinnedFilenames()
    template <typename FUNCTION>
    void walkSearchSkinDirs(const std::string& subdir,
                            const std::vector<std::string>& subsubdirs,
                            const std::string& filename,
                            const FUNCTION& function) const;

    std::string mAppName;               // install directory under progams/ ie "SecondLife"
    std::string mExecutablePathAndName; // full path + Filename of .exe
    std::string mExecutableFilename;    // Filename of .exe
    std::string mExecutableDir;      // Location of executable
    std::string mWorkingDir;         // Current working directory
    std::string mAppRODataDir;           // Location for static app data
    std::string mOSUserDir;          // OS Specific user directory
    std::string mOSUserAppDir;           // OS Specific user app directory
    std::string mLindenUserDir;      // Location for Linden user-specific data
    std::string mPerAccountChatLogsDir;      // Location for chat logs.
    std::string mChatLogsDir;        // Location for chat logs.
    std::string mCAFile;                 // Location of the TLS certificate authority PEM file.
    std::string mTempDir;
    std::string mCacheDir;          // cache directory as set by user preference
    std::string mDefaultCacheDir;   // default cache diretory
    std::string mOSCacheDir;        // operating system cache dir
    std::string mDirDelimiter;
    std::string mSkinName;           // caller-specified skin name
    std::string mSkinBaseDir;           // Base for skins paths.
    std::string mDefaultSkinDir;            // Location for default skin info.
    std::string mSkinDir;           // Location for current skin info.
    std::string mUserDefaultSkinDir;        // Location for default skin info.
    std::string mUserSkinDir;           // Location for user-modified skin info.
    // Skin directories to search, most general to most specific. This order
    // works well for composing fine-grained files, in which an individual item
    // in a specific file overrides the corresponding item in more general
    // files. Of course, for a file-level search, iterate backwards.
    std::vector<std::string> mSearchSkinDirs;
    std::string mLanguage;              // Current viewer language
    std::string mLLPluginDir;           // Location for plugins and plugin shell
    static std::string sDumpDir;            // Per-run crash report subdir of log directory.
    std::string mUserName;              // Current user name
};

void dir_exists_or_crash(const std::string &dir_name);

extern LLDir *gDirUtilp;

#endif // LL_LLDIR_H