package parquet

import (
	
	

	
	
)

// RowBuffer is an implementation of the RowGroup interface which stores parquet
// rows in memory.
//
// Unlike GenericBuffer which uses a column layout to store values in memory
// buffers, RowBuffer uses a row layout. The use of row layout provides greater
// efficiency when sorting the buffer, which is the primary use case for the
// RowBuffer type. Applications which intend to sort rows prior to writing them
// to a parquet file will often see lower CPU utilization from using a RowBuffer
// than a GenericBuffer.
//
// RowBuffer values are not safe to use concurrently from multiple goroutines.
type RowBuffer[ any] struct {
	alloc   rowAllocator
	schema  *Schema
	sorting []SortingColumn
	rows    []Row
	values  []Value
	compare func(Row, Row) int
}

// NewRowBuffer constructs a new row buffer.
func [ any]( ...RowGroupOption) *RowBuffer[] {
	 := DefaultRowGroupConfig()
	.Apply(...)
	if  := .Validate();  != nil {
		panic()
	}

	 := typeOf[]()
	if .Schema == nil &&  != nil {
		.Schema = schemaOf(dereference())
	}

	if .Schema == nil {
		panic("row buffer must be instantiated with schema or concrete type.")
	}

	return &RowBuffer[]{
		schema:  .Schema,
		sorting: .Sorting.SortingColumns,
		compare: .Schema.Comparator(.Sorting.SortingColumns...),
	}
}

// Reset clears the content of the buffer without releasing its memory.
func ( *RowBuffer[]) () {
	for  := range .rows {
		.rows[] = nil
	}
	for  := range .values {
		.values[] = Value{}
	}
	.rows = .rows[:0]
	.values = .values[:0]
	.alloc.reset()
}

// NumRows returns the number of rows currently written to the buffer.
func ( *RowBuffer[]) () int64 { return int64(len(.rows)) }

// ColumnChunks returns a view of the buffer's columns.
//
// Note that reading columns of a RowBuffer will be less efficient than reading
// columns of a GenericBuffer since the latter uses a column layout. This method
// is mainly exposed to satisfy the RowGroup interface, applications which need
// compute-efficient column scans on in-memory buffers should likely use a
// GenericBuffer instead.
//
// The returned column chunks are snapshots at the time the method is called,
// they remain valid until the next call to Reset on the buffer.
func ( *RowBuffer[]) () []ColumnChunk {
	 := .schema.Columns()
	 := make([]rowBufferColumnChunk, len())

	for ,  := range  {
		,  := .schema.Lookup(...)
		[] = rowBufferColumnChunk{
			page: rowBufferPage{
				rows:               .rows,
				typ:                .Node.Type(),
				column:             .ColumnIndex,
				maxRepetitionLevel: byte(.MaxRepetitionLevel),
				maxDefinitionLevel: byte(.MaxDefinitionLevel),
			},
		}
	}

	 := make([]ColumnChunk, len())
	for  := range  {
		[] = &[]
	}
	return 
}

// SortingColumns returns the list of columns that rows are expected to be
// sorted by.
//
// The list of sorting columns is configured when the buffer is created and used
// when it is sorted.
//
// Note that unless the buffer is explicitly sorted, there are no guarantees
// that the rows it contains will be in the order specified by the sorting
// columns.
func ( *RowBuffer[]) () []SortingColumn { return .sorting }

// Schema returns the schema of rows in the buffer.
func ( *RowBuffer[]) () *Schema { return .schema }

// Len returns the number of rows in the buffer.
//
// The method contributes to satisfying sort.Interface.
func ( *RowBuffer[]) () int { return len(.rows) }

// Less compares the rows at index i and j according to the sorting columns
// configured on the buffer.
//
// The method contributes to satisfying sort.Interface.
func ( *RowBuffer[]) (,  int) bool {
	return .compare(.rows[], .rows[]) < 0
}

// Swap exchanges the rows at index i and j in the buffer.
//
// The method contributes to satisfying sort.Interface.
func ( *RowBuffer[]) (,  int) {
	.rows[], .rows[] = .rows[], .rows[]
}

// Rows returns a Rows instance exposing rows stored in the buffer.
//
// The rows returned are a snapshot at the time the method is called.
// The returned rows and values read from it remain valid until the next call
// to Reset on the buffer.
func ( *RowBuffer[]) () Rows {
	return &rowBufferRows{rows: .rows, schema: .schema}
}

// Write writes rows to the buffer, returning the number of rows written.
func ( *RowBuffer[]) ( []) (int, error) {
	for  := range  {
		 := len(.values)
		.values = .schema.Deconstruct(.values, &[])
		 := len(.values)
		 := .values[::]
		.alloc.capture()
		.rows = append(.rows, )
	}
	return len(), nil
}

// WriteRows writes parquet rows to the buffer, returing the number of rows
// written.
func ( *RowBuffer[]) ( []Row) (int, error) {
	for  := range  {
		 := len(.values)
		.values = append(.values, []...)
		 := len(.values)
		 := .values[::]
		.alloc.capture()
		.rows = append(.rows, )
	}
	return len(), nil
}

type rowBufferColumnChunk struct{ page rowBufferPage }

func ( *rowBufferColumnChunk) () Type { return .page.Type() }

func ( *rowBufferColumnChunk) () int { return .page.Column() }

func ( *rowBufferColumnChunk) () Pages { return onePage(&.page) }

func ( *rowBufferColumnChunk) () (ColumnIndex, error) { return nil, nil }

func ( *rowBufferColumnChunk) () (OffsetIndex, error) { return nil, nil }

func ( *rowBufferColumnChunk) () BloomFilter { return nil }

func ( *rowBufferColumnChunk) () int64 { return .page.NumValues() }

type rowBufferPage struct {
	rows               []Row
	typ                Type
	column             int
	maxRepetitionLevel byte
	maxDefinitionLevel byte
}

func ( *rowBufferPage) () Type { return .typ }

func ( *rowBufferPage) () int { return .column }

func ( *rowBufferPage) () Dictionary { return nil }

func ( *rowBufferPage) () int64 { return int64(len(.rows)) }

func ( *rowBufferPage) () int64 {
	 := int64(0)
	.scan(func( Value) {
		if !.isNull() {
			++
		}
	})
	return 
}

func ( *rowBufferPage) () int64 {
	 := int64(0)
	.scan(func( Value) {
		if .isNull() {
			++
		}
	})
	return 
}

func ( *rowBufferPage) () (,  Value,  bool) {
	.scan(func( Value) {
		if !.IsNull() {
			switch {
			case !:
				, ,  = , , true
			case .typ.Compare(, ) < 0:
				 = 
			case .typ.Compare(, ) > 0:
				 = 
			}
		}
	})
	return , , 
}

func ( *rowBufferPage) () int64 { return 0 }

func ( *rowBufferPage) () ValueReader {
	return &rowBufferPageValueReader{
		page:        ,
		columnIndex: ^int16(.column),
	}
}

func ( *rowBufferPage) () Page {
	 := make([]Row, len(.rows))
	for  := range  {
		[] = .rows[].Clone()
	}
	return &rowBufferPage{
		rows:   ,
		typ:    .typ,
		column: .column,
	}
}

func ( *rowBufferPage) (,  int64) Page {
	return &rowBufferPage{
		rows:   .rows[:],
		typ:    .typ,
		column: .column,
	}
}

func ( *rowBufferPage) () ( []byte) {
	if .maxRepetitionLevel != 0 {
		 = make([]byte, 0, len(.rows))
		.scan(func( Value) {
			 = append(, .repetitionLevel)
		})
	}
	return 
}

func ( *rowBufferPage) () ( []byte) {
	if .maxDefinitionLevel != 0 {
		 = make([]byte, 0, len(.rows))
		.scan(func( Value) {
			 = append(, .definitionLevel)
		})
	}
	return 
}

func ( *rowBufferPage) () encoding.Values {
	switch .typ.Kind() {
	case Boolean:
		 := make([]byte, (len(.rows)+7)/8)
		 := 0
		.scanNonNull(func( Value) {
			if .boolean() {
				 := uint() / 8
				 := uint() % 8
				[] |= 1 << 
			}
			++
		})
		return encoding.BooleanValues([:(+7)/8])

	case Int32:
		 := make([]int32, 0, len(.rows))
		.scanNonNull(func( Value) {  = append(, .int32()) })
		return encoding.Int32Values()

	case Int64:
		 := make([]int64, 0, len(.rows))
		.scanNonNull(func( Value) {  = append(, .int64()) })
		return encoding.Int64Values()

	case Int96:
		 := make([]deprecated.Int96, 0, len(.rows))
		.scanNonNull(func( Value) {  = append(, .int96()) })
		return encoding.Int96Values()

	case Float:
		 := make([]float32, 0, len(.rows))
		.scanNonNull(func( Value) {  = append(, .float()) })
		return encoding.FloatValues()

	case Double:
		 := make([]float64, 0, len(.rows))
		.scanNonNull(func( Value) {  = append(, .double()) })
		return encoding.DoubleValues()

	case ByteArray:
		 := make([]byte, 0, .typ.EstimateSize(len(.rows)))
		 := make([]uint32, 0, len(.rows))
		.scanNonNull(func( Value) {
			 = append(, uint32(len()))
			 = append(, .byteArray()...)
		})
		 = append(, uint32(len()))
		return encoding.ByteArrayValues(, )

	case FixedLenByteArray:
		 := .typ.Length()
		 := make([]byte, 0, *len(.rows))
		.scanNonNull(func( Value) {  = append(, .byteArray()...) })
		return encoding.FixedLenByteArrayValues(, )

	default:
		return encoding.Values{}
	}
}

func ( *rowBufferPage) ( func(Value)) {
	 := ^int16(.column)

	for ,  := range .rows {
		for ,  := range  {
			if .columnIndex ==  {
				()
			}
		}
	}
}

func ( *rowBufferPage) ( func(Value)) {
	.scan(func( Value) {
		if !.isNull() {
			()
		}
	})
}

type rowBufferPageValueReader struct {
	page        *rowBufferPage
	rowIndex    int
	valueIndex  int
	columnIndex int16
}

func ( *rowBufferPageValueReader) ( []Value) ( int,  error) {
	for  < len() && .rowIndex < len(.page.rows) {
		for  < len() && .valueIndex < len(.page.rows[.rowIndex]) {
			if  := .page.rows[.rowIndex][.valueIndex]; .columnIndex == .columnIndex {
				[] = 
				++
			}
			.valueIndex++
		}
		.rowIndex++
		.valueIndex = 0
	}
	if .rowIndex == len(.page.rows) {
		 = io.EOF
	}
	return , 
}

type rowBufferRows struct {
	rows   []Row
	index  int
	schema *Schema
}

func ( *rowBufferRows) () error {
	.index = -1
	return nil
}

func ( *rowBufferRows) () *Schema {
	return .schema
}

func ( *rowBufferRows) ( int64) error {
	if  < 0 {
		return ErrSeekOutOfRange
	}

	if .index < 0 {
		return io.ErrClosedPipe
	}

	 := int64(len(.rows))
	if  >  {
		 = 
	}

	.index = int()
	return nil
}

func ( *rowBufferRows) ( []Row) ( int,  error) {
	if .index < 0 {
		return 0, io.EOF
	}

	if  = len(.rows) - .index;  > len() {
		 = len()
	}

	for ,  := range .rows[.index : .index+] {
		[] = append([][:0], ...)
	}

	if .index += ; .index == len(.rows) {
		 = io.EOF
	}

	return , 
}

func ( *rowBufferRows) ( RowWriter) (int64, error) {
	,  := .WriteRows(.rows[.index:])
	.index += 
	return int64(), 
}

var (
	_ RowGroup       = (*RowBuffer[any])(nil)
	_ RowWriter      = (*RowBuffer[any])(nil)
	_ sort.Interface = (*RowBuffer[any])(nil)

	_ RowWriterTo = (*rowBufferRows)(nil)
)