#include <DB/DataStreams/InputStreamFromASTInsertQuery.h>

namespace DB
{

InputStreamFromASTInsertQuery::InputStreamFromASTInsertQuery(
	const ASTPtr & ast, ReadBuffer & input_buffer_tail_part, const BlockIO & streams, Context & context)
{
	const ASTInsertQuery * ast_insert_query = dynamic_cast<const ASTInsertQuery *>(ast.get());

	if (!ast_insert_query)
		throw Exception("Logical error: query requires data to insert, but it is not INSERT query", ErrorCodes::LOGICAL_ERROR);

	String format = ast_insert_query->format;
	if (format.empty())
		format = "Values";

	/// Data could be in parsed (ast_insert_query.data) and in not parsed yet (input_buffer_tail_part) part of query.

	input_buffer_ast_part = std::make_unique<ReadBuffer>(
		const_cast<char *>(ast_insert_query->data), ast_insert_query->data ? ast_insert_query->end - ast_insert_query->data : 0, 0);

	ConcatReadBuffer::ReadBuffers buffers;
	if (ast_insert_query->data)
		buffers.push_back(input_buffer_ast_part.get());
	buffers.push_back(&input_buffer_tail_part);

	/** NOTE Must not read from 'input_buffer_tail_part' before read all between 'ast_insert_query.data' and 'ast_insert_query.end'.
		* - because 'query.data' could refer to memory piece, used as buffer for 'input_buffer_tail_part'.
		*/

	input_buffer_contacenated = std::make_unique<ConcatReadBuffer>(buffers);

	res_stream = context.getInputFormat(format, *input_buffer_contacenated, streams.out_sample, context.getSettings().max_insert_block_size);
}

}