package wireproto

import (
	`bytes`
	`fmt`
	`io`
	`strings`

	`github.com/google/uuid`
)

// ConnId returns a copy of the connection ID.
func (r *RequestRecordGroup) ConnId() (conn uuid.UUID) {

	conn = r.connId

	return
}

// GetParent returns this RecordGroup's Message.
func (r *RequestRecordGroup) GetParent() (msg Message) {

	msg = r.parent

	return
}

// MarshalBinary renders a RequestRecordGroup into a byte-packed format.
func (r *RequestRecordGroup) MarshalBinary() (data []byte, err error) {

	var b []byte
	var rgSize int
	var buf *bytes.Buffer = new(bytes.Buffer)

	_ = r.Size()

	for _, i := range r.Records {
		rgSize += i.Size()
	}

	// Count
	if _, err = buf.Write(PackInt(len(r.Records))); err != nil {
		return
	}
	// Size
	if _, err = buf.Write(PackInt(rgSize)); err != nil {
		return
	}

	for _, i := range r.Records {
		if b, err = i.MarshalBinary(); err != nil {
			return
		}
		if _, err = buf.Write(b); err != nil {
			return
		}
	}

	data = buf.Bytes()

	return
}

// Model returns an indented string representation of the model.
func (r *RequestRecordGroup) Model() (out string) {

	out = r.ModelCustom(IndentChars, SeparatorChars, indentRG)

	return
}

// ModelCustom is like Model with user-defined formatting.
func (r *RequestRecordGroup) ModelCustom(indent, sep string, level uint) (out string) {

	var size int
	var sb strings.Builder

	for _, rec := range r.Records {
		size += rec.Size()
	}

	// Count
	sb.WriteString(strings.Repeat(indent, int(level)))
	sb.WriteString(fmt.Sprintf("%x", PackUint32(uint32(len(r.Records)))))
	sb.WriteString(sep)
	sb.WriteString(fmt.Sprintf("// Record Count      (%d)\n", len(r.Records)))
	// Size
	sb.WriteString(strings.Repeat(indent, int(level)))
	sb.WriteString(fmt.Sprintf("%x", PackUint32(uint32(size))))
	sb.WriteString(sep)
	sb.WriteString(fmt.Sprintf("// Record Group Size (%d)\n", size))

	// VALUES
	for idx, rec := range r.Records {
		sb.WriteString(strings.Repeat(indent, int(level)))
		sb.WriteString(
			fmt.Sprintf(
				"// Record Group %d, Record %d (%d bytes)\n",
				r.rgIdx+1, idx+1, rec.Size(),
			),
		)
		sb.WriteString(rec.ModelCustom(indent, sep, level+1))
	}

	out = sb.String()

	return
}

// Resolve associates children with parents.
func (r *RequestRecordGroup) Resolve() {
	for idx, i := range r.Records {
		i.parent = r
		i.rgIdx = r.rgIdx
		i.rIdx = idx
		i.Resolve()
	}
}

// Size returns the RequestRecordGroup's calculated size (in bytes) and updates the size field if 0.
func (r *RequestRecordGroup) Size() (size int) {

	if r == nil {
		return
	}

	// Count and Size uint32s
	size += PackedNumSize * 2

	for _, p := range r.Records {
		size += p.Size()
	}

	if r.common == nil || r.size == 0 {
		r.common = new(common)
	}

	r.common.size = uint32(size)

	return
}

// ToMap returns a slice of slice of FVP maps for this RecordGroup.
func (r *RequestRecordGroup) ToMap() (m [][]map[string]interface{}) {

	m = make([][]map[string]interface{}, len(r.Records))
	for idx, rec := range r.Records {
		m[idx] = rec.ToMap()
	}

	return
}

// UnmarshalBinary populates a RequestRecordGroup from packed bytes.
func (r *RequestRecordGroup) UnmarshalBinary(data []byte) (err error) {

	if data == nil || len(data) == 0 {
		return
	}

	var b []byte
	var cnt, size int
	var recSize int
	var recBuf *bytes.Buffer
	var buf *bytes.Reader = bytes.NewReader(data)

	if r == nil {
		*r = RequestRecordGroup{}
	}
	if r.common == nil {
		r.common = new(common)
	}
	r.size = 0

	// The record count.
	b = make([]byte, PackedNumSize)
	if _, err = buf.Read(b); err != nil {
		return
	}
	cnt = UnpackInt(b)

	// The record group size.
	b = make([]byte, PackedNumSize)
	if _, err = buf.Read(b); err != nil {
		return
	}
	size = UnpackInt(b)

	b = make([]byte, size)
	if _, err = buf.Read(b); err != nil {
		return
	}

	// Get a new buf for the actual records.
	buf = bytes.NewReader(b)

	r.Records = make([]*RequestRecord, cnt)

	for idx := 0; idx < cnt; idx++ {
		recBuf = new(bytes.Buffer)

		// We skip over the KVP count; that's handled in the record Unmarshaler.
		// We *do*, however, need to save it to the recBuf.
		if _, err = io.CopyN(recBuf, buf, int64(PackedNumSize)); err != nil {
			return
		}

		// Size of the actual record
		b = make([]byte, PackedNumSize)
		if _, err = buf.Read(b); err != nil {
			return
		}
		if _, err = recBuf.Write(b); err != nil {
			return
		}
		recSize = UnpackInt(b)

		if _, err = io.CopyN(recBuf, buf, int64(recSize)); err != nil {
			return
		}

		r.Records[idx] = new(RequestRecord)
		if err = r.Records[idx].UnmarshalBinary(recBuf.Bytes()); err != nil {
			return
		}
	}

	_ = r.Size()

	return
}

// getIdx returns the RecordGroup index in the parent Message.
func (r *RequestRecordGroup) getIdx() (idx int) {

	idx = r.rgIdx

	return
}

// getRecords returns the Records in this RecordGroup.
func (r *RequestRecordGroup) getRecords() (records []Record) {

	records = make([]Record, len(r.Records))
	for idx, rec := range r.Records {
		records[idx] = rec
	}

	return
}