package models

import (
	"encoding/json"
	"io/ioutil"
	"os"
	"time"

	"github.com/google/uuid"
	"github.com/jmoiron/jsonq"
	"github.com/sirupsen/logrus"
)

const (
	nodesFilename = "nodes.json"
	edgesFilename = "edges.json"
)

// Node defines the data we gather through the parsing.
type Node struct {
	ID   uuid.UUID
	Flag string `json:"flag"`
}

// Edge defines a relation between two nodes.
type Edge struct {
	ID        uuid.UUID
	NodeOneID uuid.UUID `json:"NodeOneID"`
	// NodeTwoID uuid.UUID `json:NodeTwoID` to implement
	Timestamp time.Time       `json:"Timestamp"`
	Data      jsonq.JsonQuery `json:"Data"`
}

// SaveData is the main function used to save data. You need to pass a specific
// flag to it and the data recieved. It just saves data, it doesn't filter or
// look for it in the stream.
func SaveData(flag string, data jsonq.JsonQuery) {
	err := fileExists(nodesFilename)
	if err != nil {
		logrus.Error(err)
	}

	err = fileExists(edgesFilename)
	if err != nil {
		logrus.Error(err)
	}

	nodeFile, err := ioutil.ReadFile(nodesFilename)
	if err != nil {
		logrus.Error(err)
	}

	edgeFile, err := ioutil.ReadFile(edgesFilename)
	if err != nil {
		logrus.Error(err)
	}

	nodeDatas := []Node{}
	edgeDatas := []Edge{}

	json.Unmarshal(nodeFile, &nodeDatas)
	json.Unmarshal(edgeFile, &edgeDatas)

	node := &Node{
		ID:   uuid.New(),
		Flag: flag,
	}

	edge := &Edge{
		ID:        uuid.New(),
		NodeOneID: node.ID,
		Timestamp: time.Now(),
		Data:      data,
	}

	nodeDatas = append(nodeDatas, *node)
	edgeDatas = append(edgeDatas, *edge)

	nodeBytes, err := json.Marshal(nodeDatas)
	if err != nil {
		logrus.Error(err)
	}

	edgeBytes, err := json.Marshal(edgeDatas)
	if err != nil {
		logrus.Error(err)
	}

	err = ioutil.WriteFile(nodesFilename, nodeBytes, 0644)
	if err != nil {
		logrus.Error(err)
	}

	err = ioutil.WriteFile(edgesFilename, edgeBytes, 0644)
	if err != nil {
		logrus.Error(err)
	}
}

// Helpers

func fileExists(filename string) error {
	_, err := os.Stat(filename)
	if os.IsNotExist(err) {
		_, err := os.Create(filename)
		if err != nil {
			return err
		}
	}

	return nil
}