package virtbuf

// functions to import and export the protobuf
// data to and from config files

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"

	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/encoding/prototext"
	"google.golang.org/protobuf/reflect/protoreflect"
)

// writes out the cluster information it seperate files
// to make it humanly possible to hand edit things as needed
func (c *NewCluster) ConfigSave() error {
	// try to backup the current cluster config files
	if err := backupConfig(); err != nil {
		return err
	}

	// make a new droplets struct
	var dcopy *Droplets
	dcopy = new(Droplets)
	loop := c.DropletsAll() // get the list of droplets
	for loop.Scan() {
		d := loop.Droplet()
		var newd Droplet
		newd = *d
		dcopy.Droplets = append(dcopy.Droplets, &newd)
	}
	// delete all the Current data so it's not put in the config file
	for _, drop := range dcopy.Droplets {
		drop.Current = nil
	}
	if err := ConfigWriteJSON(dcopy, "droplets.json"); err != nil {
		fmt.Println("droplets.json write failed")
		return err
	}
	if err := ConfigWriteTEXT(dcopy, "droplets.text"); err != nil {
		fmt.Println("droplets.json write failed")
		return err
	}

	if err := ConfigWriteJSON(c.H, "hypervisors.json"); err != nil {
		fmt.Println("hypervisors.json write failed")
		return err
	}
	if err := ConfigWriteTEXT(c.H, "hypervisors.text"); err != nil {
		fmt.Println("hypervisors.json write failed")
		return err
	}

	if err := ConfigWriteJSON(c.e, "events.json"); err != nil {
		fmt.Println("events.json write failed")
		return err
	}
	if err := ConfigWriteTEXT(c.e, "events.text"); err != nil {
		fmt.Println("events.json write failed")
		return err
	}
	return nil
}

func (c *NewCluster) ConfigLoad() error {
	if c == nil {
		return errors.New("It's not safe to run ConfigLoad() on a nil cluster")
	}

	if data, err := loadFile("droplets.json"); err == nil {
		if err = protojson.Unmarshal(data, c.d); err != nil {
			fmt.Println("broken droplets.json config file")
			return err
		}
	} else {
		return err
	}

	if data, err := loadFile("hypervisors.json"); err == nil {
		if err = protojson.Unmarshal(data, c.H); err != nil {
			fmt.Println("broken hypervisors.json config file")
			return err
		}
	} else {
		fmt.Println("ERROR HERE IN Hypervisors")
		return err
	}

	if c.e == nil {
		// this seems to panic on nil. something is wrong about doing this
		// does it not stay allocated after this function ends?
		c.e = new(Events)
	}
	if err := c.e.loadEvents(); err != nil {
		return err
	}
	return nil
}

func (e *Events) loadEvents() error {
	var data []byte
	var err error

	// load the events config file
	if data, err = loadFile("events.json"); err != nil {
		fmt.Println("broken events.json config file")
		return err
	}

	err = protojson.Unmarshal(data, e)
	if err != nil {
		fmt.Println("broken events.json config file")
		// json load failed. try loading prototext
		if data, err = loadFile("events.text"); err != nil {
			fmt.Println("broken events.text config file")
			fmt.Println(err)
			return errors.New("events.text file is broken")
		}
		if err = prototext.Unmarshal(data, e); err != nil {
			fmt.Println("broken events.text config file")
			fmt.Println(err)
			return errors.New("events.text file is broken")
		}
	}
	return nil
}

func loadFile(filename string) ([]byte, error) {
	fullname := filepath.Join(os.Getenv("VIRTIGO_HOME"), filename)
	data, err := os.ReadFile(fullname)
	if err != nil {
		// log.Info("open config file :", err)
		return nil, err
	}
	return data, nil
}

// reads in from the prototext file
// prototext file formats are not garrenteed to be stable. todo: hammer that out

func ConfigWriteJSON(a any, filename string) error {
	fullname := filepath.Join(os.Getenv("VIRTIGO_HOME"), filename)
	cfgfile, err := os.OpenFile(fullname, os.O_RDWR|os.O_CREATE, 0666)
	defer cfgfile.Close()
	if err != nil {
		fmt.Println("open config file :", err)
		return err
	}
	msg, ok := a.(protoreflect.ProtoMessage)
	if !ok {
		return fmt.Errorf("provided value does not implement protoreflect.ProtoMessage")
	}
	text := protojson.Format(msg)
	fmt.Fprintln(cfgfile, text)
	return nil
}

func ConfigWriteTEXT(a any, filename string) error {
	fullname := filepath.Join(os.Getenv("VIRTIGO_HOME"), filename)
	cfgfile, err := os.OpenFile(fullname, os.O_RDWR|os.O_CREATE, 0666)
	defer cfgfile.Close()
	if err != nil {
		fmt.Println("open config file :", err)
		return err
	}
	msg, ok := a.(protoreflect.ProtoMessage)
	if !ok {
		return fmt.Errorf("provided value does not implement protoreflect.ProtoMessage")
	}
	text := prototext.Format(msg)
	fmt.Fprintln(cfgfile, text)
	return nil
}