package handler

import (
	"bytes"
	"encoding/json"
	"errors"
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	"github.com/google/uuid"
	"github.com/xuri/excelize/v2"
	"gitstore.ru/tolikproh/sirius/internal/model"
)

var (
	TEXT_TYPES = map[string]interface{}{
		"text/plain; charset=utf-8": nil,
	}
)

func (s *Handler) GinConvert(c *gin.Context) {
	sessionId := uuid.New().String()

	s.log.Printf("start convert. session id: %s; user agent: %s; remote addr: %s; file size [byte]: %d",
		sessionId, c.Request.UserAgent(), c.Request.RemoteAddr, c.Request.ContentLength)

	c.Request.Body = http.MaxBytesReader(c.Writer, c.Request.Body, s.cfg.Srv.MaxSizeFile<<20)

	file, fileHeader, err := c.Request.FormFile("file")
	if err != nil {
		s.log.Errorf("session id: %s. error code: 001. %s", sessionId, err.Error())
		c.JSON(http.StatusBadRequest, gin.H{
			"error": err.Error(),
		})
		return
	}
	defer file.Close()

	buffer := make([]byte, fileHeader.Size)
	file.Read(buffer)

	buffer = bytes.TrimPrefix(buffer, []byte("\xef\xbb\xbf"))

	fileType := http.DetectContentType(buffer)

	// Validate File Type
	if _, ex := TEXT_TYPES[fileType]; !ex {
		s.log.Errorf("session id: %s. error code: 002. formated data not text/plain", sessionId)
		c.JSON(http.StatusBadRequest, gin.H{
			"error": errors.New("formated data not text/plain").Error(),
		})
		return
	}

	if !json.Valid(buffer) {
		s.log.Errorf("session id: %s. error code: 003. formated data not json", sessionId)
		c.JSON(http.StatusBadRequest, gin.H{
			"error": errors.New("formated data not json").Error(),
		})
		return
	}

	var sirius model.Sirius

	err = json.Unmarshal(buffer, &sirius)
	if err != nil {
		s.log.Errorf("session id: %s. error code: 004. %s", sessionId, err.Error())
		c.JSON(http.StatusBadRequest, gin.H{
			"error": errors.New("Error unmarshal file").Error(),
		})
		return
	}

	buff, err := SaveToExel(sirius.NewBolid().ZoneInfo())
	if err != nil {
		s.log.Errorf("session id: %s. error code: 005. %s", sessionId, err.Error())
		c.JSON(http.StatusBadRequest, gin.H{
			"error": errors.New("Error create file").Error(),
		})
		return
	}

	c.Data(200, "application/vnd.ms-excel", buff.Bytes())

	s.log.Printf("session id: %s.converted: ok. filename: %s; file size: %d bytes", sessionId, fileHeader.Filename, fileHeader.Size)

}

func SaveToExel(data []model.ZoneInfo) (*bytes.Buffer, error) {
	f := excelize.NewFile()
	defer f.Close()

	// Create a new sheet.
	f.SetCellValue("Sheet1", "A2", "№ зоны")
	f.SetCellValue("Sheet1", "B2", "Описание зоны")
	f.SetCellValue("Sheet1", "C2", "Адреса в зоне")
	i := 3
	for _, d := range data {
		f.SetCellValue("Sheet1", "A"+strconv.Itoa(i), d.ZoneNum)
		f.SetCellValue("Sheet1", "B"+strconv.Itoa(i), d.ZoneName)
		f.SetCellValue("Sheet1", "C"+strconv.Itoa(i), d.InputString())
		i++
	}

	return f.WriteToBuffer()
}