// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

package fan

import (
_	"context"
_	"encoding/json"
	"fmt"
_	"gopkg.in/yaml.v3"
	"net/url"
_	"path/filepath"
	"decl/internal/data"
	"decl/internal/resource"
	"decl/internal/folio"
_	"os"
_	"io"
	"strings"
	"log/slog"
)

type Iptable struct {
	Table string `yaml:"table" json:"table"`
	Chain string `yaml:"chain" json:"chain"`
}

func NewIptable() *Iptable {
	return &Iptable{}
}

func init() {
	folio.DocumentRegistry.ConverterTypes.Register([]string{"iptable"}, func(u *url.URL) data.Converter {
		t := NewIptable()
		t.Table = u.Hostname()
		elements := strings.FieldsFunc(u.Path, func(c rune) bool { return c == '/' })
		if len(elements) >= 1 {
			t.Chain = elements[0]
		}
		slog.Info("iptable chain source factory", "table", t, "uri", u, "table", u.Hostname()) 
		return t
	})

}


func (i *Iptable) Type() data.TypeName { return "iptable" }

func (i *Iptable) Extract(sourceResource data.Resource, filter data.ElementSelector) (document data.Document, err error) {

	slog.Info("fan.Iptable.Extract()", "table", i) 

	iptRules := make([]*resource.Iptable, 0, 100)
	cmd := resource.NewIptableReadChainCommand()
	if cmd == nil {
		return document, fmt.Errorf("Iptable read chain: invalid command")
	}

	var out []byte
	if out, err = cmd.Execute(i); err == nil {

		if err = cmd.Extractor(out, &iptRules); err == nil {
			document = folio.DocumentRegistry.NewDocument(folio.URI(sourceResource.URI()))
			for _, rule := range iptRules {
				if rule == nil {
					rule = resource.NewIptable()
				}
				rule.Table = resource.IptableName(i.Table)
				rule.Chain = resource.IptableChain(i.Chain)
				slog.Info("iptable chain source Extract()", "rule", rule)
				document.(*folio.Document).AddResourceDeclaration("iptable", rule)
			}
		}
	}
	slog.Info("fan.Iptable.Extract()", "output", out, "error", err)
	return document, err
}

func (i *Iptable) Emit(document data.Document, filter data.ElementSelector) (resourceTarget data.Resource, err error) {
	return nil, nil
}

func (i *Iptable) Close() error {
	return nil
}