/*
 * libfud
 * Copyright 2025 Dominick Allen
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef FUD_CSV_HPP
#define FUD_CSV_HPP

#include "fud_file.hpp"
#include "fud_status.hpp"
#include "fud_string_view.hpp"
#include "fud_text.hpp"
#include "fud_utf8.hpp"
#include "fud_vector.hpp"

namespace fud {

using TextBuffer = Vector<std::byte>;

struct Csv {
    /** \brief The number of lines of data in the CSV. */
    size_t numLines{0};

    /** \brief The number of columns in the CSV. */
    size_t numColumns{0};

    /** \brief Buffer for each line with numColumns of StringView. */
    Vector<StringView> entries;

    /** \brief Backing buffer for data. */
    Vector<utf8> buffer;

    /** \separator for each column */
    Utf8 columnDelimiter{Ascii{','}};

    Utf8 quoteCharacter{Ascii{'"'}};

    /** \separator for each line */
    NewlineRepr newlineDelimiter{NewlineRepr::Posix};

    bool strictUtf8{true};

    bool strictColumns{true};

    bool strictQuote{false};

    bool skipInitialSpace{false};

    /** \brief Uses global Fud allocator for lines and backing buffer. */
    static Csv makeDefault();

    /** \brief Specify allocator to use for both lines and backing buffer. */
    static Csv makeWithSingleAllocator(Allocator& allocator);

    /** \brief Specify allocator. */
    static Csv make(Allocator& entryAllocator, Allocator& bufferAllocator);

    /** Consume and return the CSV. */
    static FudStatus parseFromFilenameUnbuffered(
        Csv& csv,
        StringView filename,
        OpenFlags flags = OpenFlags{},
        Option<int> dirFdOption = NullOpt,
        size_t maxExtraAttempts = 0);

    static FudStatus parseFromFilenameBuffered(
        Csv& csv,
        TextBuffer&& buffer,
        StringView filename,
        OpenFlags flags = OpenFlags{},
        Option<int> dirFdOption = NullOpt,
        size_t maxExtraAttempts = 0);

    // assumes file is at start
    static FudStatus parseFromUnbufferedFile(Csv& csv, RegularFile&& file, size_t maxExtraAttempts);

    // assumes file is at start
    static FudStatus parseFromBufferedFile(Csv& csv, BufferedRegularFile& file, size_t maxExtraAttempts);

    [[nodiscard]] Result<Option<StringView>, FudStatus> entry(size_t line, size_t column) const;
};

} // namespace fud

#endif