package main

import (
	"bufio"
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
)

var (
	// TOKEN token
	TOKEN = "08bb51ff-1eb6-4167-8ed2-eb19fc343703"
	// MICROSERVICEURL url to microservie
	MICROSERVICEURL = "http://microservice01:8081/api/v1/documents/create?crptDocType=LP_INTRODUCE_OST"
)

// Hello ...
func Hello(name string) string {
	if name == "" {
		name = "World"
	}
	return fmt.Sprintf("Hello, %s", name)
}

// ParseFile ...
func ParseFile(fileName string) ([]string, error) {
	if fileName == "" {
		return nil, errors.New("Empty file path")
	}
	file, err := os.Open(fileName)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	scanner := bufio.NewScanner(file)

	var lines []string

	for scanner.Scan() {
		lines = append(lines, scanner.Text())
	}
	return lines, nil
}

// SplitSlice ...
func SplitSlice(lines []string) error {
	l := len(lines)
	max := 20
	if l >= max {

		filesNum := l / max
		if l%max > 0 {
			filesNum++
		}

		files := make([]string, filesNum)

		start := 0
		end := max
		for i := 1; i <= filesNum; i++ {
			if start+max <= filesNum {
				end = start + max
			} else {
				end = start + l%max
			}
			fName := fmt.Sprintf("./out/part_%d.csv", i)
			if err := MakePartFile(lines[start:end], fName); err != nil {
				return err
			}
			files = append(files, fName)
		}
		for _, file := range files {
			SendToMicroservice(file)
		}
	}
	return nil
}

// SendToMicroservice ...
func SendToMicroservice(fileName string) error {
	lines, err := ParseFile(fileName)
	if err != nil {
		return err
	}
	products := make([]Cis, 0)
	for _, line := range lines {
		if line != "" {
			cis := NewCis(line)
			products = append(products, cis)
		}
	}
	document := NewDocument("122323", products)

	data, err := json.Marshal(document)
	if err != nil {
		return err
	}

	req, err := http.NewRequest("POST", MICROSERVICEURL, bytes.NewBuffer(data))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("token", TOKEN)

	client := http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	fmt.Println("response Status:", resp.Status)
	fmt.Println("response Headers:", resp.Header)
	body, _ := ioutil.ReadAll(resp.Body)
	fmt.Println(string(body))
	return nil
}

// MakePartFile ...
func MakePartFile(lines []string, fName string) error {
	file, err := os.OpenFile(fName, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0755)
	if err != nil {
		return err
	}
	defer file.Close()

	for _, line := range lines {
		if _, err := file.WriteString(fmt.Sprintln(line)); err != nil {
			return err
		}
	}

	return nil
}

func main() {
	Hello("")

	lines, err := ParseFile("codes.csv")
	if err != nil {
		fmt.Println(err.Error())
	}
	if err = SplitSlice(lines); err != nil {
		fmt.Println(err.Error())
	}
}