// Copyright 2023 PingCAP, Inc.
//
// 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.

#include <DataStreams/TabSeparatedRowOutputStream.h>
#include <IO/WriteHelpers.h>


namespace DB
{

TabSeparatedRowOutputStream::TabSeparatedRowOutputStream(
    WriteBuffer & ostr_,
    const Block & sample_,
    bool with_names_,
    bool with_types_)
    : ostr(ostr_)
    , sample(sample_)
    , with_names(with_names_)
    , with_types(with_types_)
{}


void TabSeparatedRowOutputStream::flush()
{
    ostr.next();
}


void TabSeparatedRowOutputStream::writePrefix()
{
    size_t columns = sample.columns();

    if (with_names)
    {
        for (size_t i = 0; i < columns; ++i)
        {
            writeEscapedString(sample.safeGetByPosition(i).name, ostr);
            writeChar(i == columns - 1 ? '\n' : '\t', ostr);
        }
    }

    if (with_types)
    {
        for (size_t i = 0; i < columns; ++i)
        {
            writeEscapedString(sample.safeGetByPosition(i).type->getName(), ostr);
            writeChar(i == columns - 1 ? '\n' : '\t', ostr);
        }
    }
}


void TabSeparatedRowOutputStream::writeField(const IColumn & column, const IDataType & type, size_t row_num)
{
    type.serializeTextEscaped(column, row_num, ostr);
}


void TabSeparatedRowOutputStream::writeFieldDelimiter()
{
    writeChar('\t', ostr);
}


void TabSeparatedRowOutputStream::writeRowEndDelimiter()
{
    writeChar('\n', ostr);
}


void TabSeparatedRowOutputStream::writeSuffix()
{
    writeExtremes();
}

void TabSeparatedRowOutputStream::writeExtremes()
{
    if (extremes)
    {
        size_t rows = extremes.rows();
        size_t columns = extremes.columns();

        writeChar('\n', ostr);

        for (size_t i = 0; i < rows; ++i)
        {
            if (i != 0)
                writeRowBetweenDelimiter();

            writeRowStartDelimiter();

            for (size_t j = 0; j < columns; ++j)
            {
                if (j != 0)
                    writeFieldDelimiter();
                writeField(*extremes.getByPosition(j).column.get(), *extremes.getByPosition(j).type.get(), i);
            }

            writeRowEndDelimiter();
        }
    }
}


} // namespace DB