package yamlfmt

import (
	"bytes"

	"sigs.k8s.io/kustomize/kyaml/kio"

	"edge-infra.dev/pkg/edge/gitops/fns/normalizer"
	"edge-infra.dev/pkg/edge/gitops/fns/trimmer"
)

type FormatterOption func(*ByteFormatter)

func WithFilterFunc(f kio.FilterFunc) FormatterOption {
	return func(bf *ByteFormatter) {
		bf.filterFuncs = append(bf.filterFuncs, f)
	}
}

func makeOptions(bf *ByteFormatter, opts ...FormatterOption) {
	for _, opt := range opts {
		opt(bf)
	}
}

func makeDefaults(bf *ByteFormatter) {
	bf.normalizer = normalizer.Normalizer{}
	bf.trimmer = trimmer.Trimmer{}
}

type ByteFormatter struct {
	normalizer  normalizer.Normalizer
	trimmer     trimmer.Trimmer
	readWriter  kio.ByteReadWriter
	filterFuncs []kio.FilterFunc
}

func NewByteFormatter() *ByteFormatter {
	bf := &ByteFormatter{
		readWriter: kio.ByteReadWriter{},
	}

	makeDefaults(bf)
	makeOptions(bf)

	return bf
}

func (bf *ByteFormatter) FormatBytes(b []byte) ([]byte, error) {
	var in, out bytes.Buffer

	_, err := in.Write(b)
	if err != nil {
		return nil, err
	}

	bf.readWriter.Reader = &in
	bf.readWriter.Writer = &out

	err = kio.Pipeline{
		Inputs:  []kio.Reader{&bf.readWriter},
		Outputs: []kio.Writer{&bf.readWriter},
		Filters: []kio.Filter{
			kio.FilterFunc(bf.trimmer.Run),
			kio.FilterFunc(bf.normalizer.Run),
		},
	}.Execute()
	if err != nil {
		return nil, err
	}

	return out.Bytes(), nil
}