/*
 * Copyright (c) 2018-2020 Atmosphère-NX
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
#pragma once
#include <stratosphere/fssystem/fssystem_dbm_rom_types.hpp>

namespace ams::fssystem {

    namespace RomPathTool {

        constexpr inline u32 MaxPathLength = 0x300;

        struct RomEntryName {
            size_t length;
            const RomPathChar *path;
        };
        static_assert(util::is_pod<RomEntryName>::value);

        constexpr void InitializeRomEntryName(RomEntryName *entry) {
            entry->length = 0;
        }

        constexpr inline bool IsSeparator(RomPathChar c) {
            return c == RomStringTraits::DirectorySeparator;
        }

        constexpr inline bool IsNullTerminator(RomPathChar c) {
            return c == RomStringTraits::NullTerminator;
        }

        constexpr inline bool IsDot(RomPathChar c) {
            return c == RomStringTraits::Dot;
        }

        constexpr inline bool IsCurrentDirectory(const RomEntryName &name) {
            return name.length == 1 && IsDot(name.path[0]);
        }

        constexpr inline bool IsCurrentDirectory(const RomPathChar *p, size_t length) {
            return length == 1 && IsDot(p[0]);
        }

        constexpr inline bool IsCurrentDirectory(const RomPathChar *p) {
            return IsDot(p[0]) && IsNullTerminator(p[1]);
        }

        constexpr inline bool IsParentDirectory(const RomEntryName &name) {
            return name.length == 2 && IsDot(name.path[0]) && IsDot(name.path[1]);
        }

        constexpr inline bool IsParentDirectory(const RomPathChar *p) {
            return IsDot(p[0]) && IsDot(p[1]) && IsNullTerminator(p[2]);
        }

        constexpr inline bool IsParentDirectory(const RomPathChar *p, size_t length) {
            return length == 2 && IsDot(p[0]) && IsDot(p[1]);
        }

        constexpr inline bool IsEqualPath(const RomPathChar *lhs, const RomPathChar *rhs, size_t length) {
            return std::strncmp(lhs, rhs, length) == 0;
        }

        constexpr inline bool IsEqualName(const RomEntryName &lhs, const RomPathChar *rhs) {
            if (strnlen(rhs, MaxPathLength) != lhs.length) {
                return false;
            }
            return IsEqualPath(lhs.path, rhs, lhs.length);
        }

        constexpr inline bool IsEqualName(const RomEntryName &lhs, const RomEntryName &rhs) {
            if (lhs.length != rhs.length) {
                return false;
            }
            return IsEqualPath(lhs.path, rhs.path, lhs.length);
        }

        Result GetParentDirectoryName(RomEntryName *out, const RomEntryName &cur, const RomPathChar *p);

        class PathParser {
            private:
                const RomPathChar *prev_path_start;
                const RomPathChar *prev_path_end;
                const RomPathChar *next_path;
                bool finished;
            public:
                constexpr PathParser() : prev_path_start(), prev_path_end(), next_path(), finished() { /* ... */ }

                Result Initialize(const RomPathChar *path);
                void Finalize();

                bool IsFinished() const;
                bool IsDirectoryPath() const;

                Result GetAsDirectoryName(RomEntryName *out) const;
                Result GetAsFileName(RomEntryName *out) const;

                Result GetNextDirectoryName(RomEntryName *out);
        };

    }

}