//===----------------------------------------------------------------------===//
//                         DuckDB
//
// duckdb/common/types/row_layout.cpp
//
//
//===----------------------------------------------------------------------===//

#include "duckdb/common/types/row_layout.hpp"

#include "duckdb/planner/expression/bound_aggregate_expression.hpp"

namespace duckdb {

RowLayout::RowLayout()
    : flag_width(0), data_width(0), aggr_width(0), row_width(0), all_constant(true), heap_pointer_offset(0) {
}

void RowLayout::Initialize(vector<LogicalType> types_p, Aggregates aggregates_p, bool align) {
	offsets.clear();
	types = move(types_p);

	// Null mask at the front - 1 bit per value.
	flag_width = ValidityBytes::ValidityMaskSize(types.size());
	row_width = flag_width;

	// Whether all columns are constant size.
	for (const auto &type : types) {
		all_constant = all_constant && TypeIsConstantSize(type.InternalType());
	}

	// This enables pointer swizzling for out-of-core computation.
	if (!all_constant) {
		// When unswizzled the pointer lives here.
		// When swizzled, the pointer is replaced by an offset.
		heap_pointer_offset = row_width;
		// The 8 byte pointer will be replaced with an 8 byte idx_t when swizzled.
		// However, this cannot be sizeof(data_ptr_t), since 32 bit builds use 4 byte pointers.
		row_width += sizeof(idx_t);
	}

	// Data columns. No alignment required.
	for (const auto &type : types) {
		offsets.push_back(row_width);
		const auto internal_type = type.InternalType();
		if (TypeIsConstantSize(internal_type) || internal_type == PhysicalType::VARCHAR) {
			row_width += GetTypeIdSize(type.InternalType());
		} else {
			// Variable size types use pointers to the actual data (can be swizzled).
			// Again, we would use sizeof(data_ptr_t), but this is not guaranteed to be equal to sizeof(idx_t).
			row_width += sizeof(idx_t);
		}
	}

	// Alignment padding for aggregates
#ifndef DUCKDB_ALLOW_UNDEFINED
	if (align) {
		row_width = AlignValue(row_width);
	}
#endif
	data_width = row_width - flag_width;

	// Aggregate fields.
	aggregates = move(aggregates_p);
	for (auto &aggregate : aggregates) {
		offsets.push_back(row_width);
		row_width += aggregate.payload_size;
#ifndef DUCKDB_ALLOW_UNDEFINED
		D_ASSERT(aggregate.payload_size == AlignValue(aggregate.payload_size));
#endif
	}
	aggr_width = row_width - data_width - flag_width;

	// Alignment padding for the next row
#ifndef DUCKDB_ALLOW_UNDEFINED
	if (align) {
		row_width = AlignValue(row_width);
	}
#endif
}

void RowLayout::Initialize(vector<LogicalType> types_p, bool align) {
	Initialize(move(types_p), Aggregates(), align);
}

void RowLayout::Initialize(Aggregates aggregates_p, bool align) {
	Initialize(vector<LogicalType>(), move(aggregates_p), align);
}

} // namespace duckdb
