package meta

import (
	"io"

	"github.com/pkg/errors"
	"github.com/vmihailenco/msgpack/v5"
)

type msgpackAssocWriter struct {
	enc        *msgpack.Encoder
	containers []writeContainer
}

type writeContainer struct {
	length int
	assoc  bool
}

func NewMsgpackAssocWriter(w io.Writer) Writer {
	return &msgpackAssocWriter{
		enc:        msgpack.NewEncoder(w),
		containers: make([]writeContainer, 0, 1),
	}
}

func (wr *msgpackAssocWriter) currentContainer() writeContainer {
	if wr == nil || len(wr.containers) == 0 {
		return writeContainer{}
	}
	return wr.containers[len(wr.containers)-1]
}

func (wr *msgpackAssocWriter) writeFieldName(field string) error {
	if !wr.currentContainer().assoc {
		return nil
	}

	return errors.WithStack(wr.enc.EncodeString(field))
}

func (wr *msgpackAssocWriter) WriteInt8(v int8, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeInt(int64(v)))
}

func (wr *msgpackAssocWriter) WriteInt16(v int16, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeInt(int64(v)))
}

func (wr *msgpackAssocWriter) WriteInt32(v int32, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeInt(int64(v)))
}

func (wr *msgpackAssocWriter) WriteInt64(v int64, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeInt(v))
}

func (wr *msgpackAssocWriter) WriteUint8(v uint8, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeUint(uint64(v)))
}

func (wr *msgpackAssocWriter) WriteUint16(v uint16, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeUint(uint64(v)))
}

func (wr *msgpackAssocWriter) WriteUint32(v uint32, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeUint(uint64(v)))
}

func (wr *msgpackAssocWriter) WriteUint64(v uint64, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeUint(uint64(v)))
}

func (wr *msgpackAssocWriter) WriteBool(v bool, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeBool(v))
}

func (wr *msgpackAssocWriter) WriteFloat32(v float32, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeFloat32(v))
}

func (wr *msgpackAssocWriter) WriteFloat64(v float64, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeFloat64(v))
}

func (wr *msgpackAssocWriter) WriteString(v string, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeString(v))
}

func (wr *msgpackAssocWriter) WriteBytes(v []byte, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	return errors.WithStack(wr.enc.EncodeBytes(v))
}

func (wr *msgpackAssocWriter) BeginContainer(length int, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	if err := wr.enc.EncodeMapLen(length); err != nil {
		return errors.WithStack(err)
	}
	wr.containers = append(wr.containers, writeContainer{
		length: length,
		assoc:  true,
	})
	return nil
}

func (wr *msgpackAssocWriter) EndContainer() error {
	if len(wr.containers) == 0 {
		return errors.New("there is no open containers")
	}
	wr.containers = wr.containers[:len(wr.containers)-1]
	return nil
}

func (wr *msgpackAssocWriter) BeginCollection(length int, field string) error {
	if err := wr.writeFieldName(field); err != nil {
		return err
	}
	if err := wr.enc.EncodeArrayLen(length); err != nil {
		return errors.WithStack(err)
	}
	wr.containers = append(wr.containers, writeContainer{
		length: length,
		assoc:  false,
	})
	return nil
}

func (wr *msgpackAssocWriter) EndCollection() error {
	return wr.EndContainer()
}