package api

import (
	"encoding/csv"
	"fmt"
	"io"
	"net/http"
	"strconv"

	"gitea.tecamino.com/paadi/memberDB/models"

	"github.com/gin-gonic/gin"
	"github.com/saintfish/chardet"
	"golang.org/x/text/encoding/charmap"
	"golang.org/x/text/transform"
)

func (a *APIHandler) AddNewMember(c *gin.Context) {
	if !a.databaseOpened(c) {
		return
	}

	var member models.Member
	c.BindJSON(&member)

	var text string
	if member.FirstName == "" {
		text = "firstName "
	}
	if member.LastName == "" {
		text += "lastName "
	}
	if member.Birthday == "" {
		text += "birthday "
	}
	if text != "" {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": text + "can not be empty",
		})
		return
	}

	err := a.DbHandler.AddNewMember(member)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message": "member added",
	})
}

func (a *APIHandler) GetMemberById(c *gin.Context) {
	if !a.databaseOpened(c) {
		return
	}

	var i int
	var err error

	id := c.Query("id")
	if id != "" {
		i, err = strconv.Atoi(id)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"message": err.Error(),
			})
			return
		}
	}

	members, err := a.DbHandler.GetMember(i)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}
	c.JSON(http.StatusOK, members)
}

func (a *APIHandler) EditMember(c *gin.Context) {
	if !a.databaseOpened(c) {
		return
	}

	var i int
	var err error

	id := c.Query("id")
	if id != "" {
		i, err = strconv.Atoi(id)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{
				"message": err.Error(),
			})
			return
		}
	} else {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": "query parameter 'id' missing",
		})
		return
	}

	var member models.Member
	c.BindJSON(&member)

	err = a.DbHandler.UpdateMember(i, member)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"message": "member updated",
	})
}

func (a *APIHandler) DeleteMember(c *gin.Context) {
	if !a.databaseOpened(c) {
		return
	}
	var err error

	var request struct {
		Ids []int `json:"ids"`
	}
	err = c.BindJSON(&request)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}

	err = a.DbHandler.DeleteMember(request.Ids...)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"message": "member deleted",
	})
}

func (a *APIHandler) ImportCSV(c *gin.Context) {
	if !a.databaseOpened(c) {
		return
	}
	var err error

	fileHeader, err := c.FormFile("file")
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}
	rowIndex := c.PostForm("rowIndex")
	comma := c.PostForm("seperator")
	firstName := c.PostForm("firstName")
	lastName := c.PostForm("lastName")
	birthday := c.PostForm("birthday")
	address := c.PostForm("address")
	town := c.PostForm("town")
	zip := c.PostForm("zip")
	phone := c.PostForm("phone")
	email := c.PostForm("email")

	rowIndexI, err := strconv.Atoi(rowIndex)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": err.Error(),
		})
		return
	}

	file, err := fileHeader.Open()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to open uploaded file"})
		return
	}
	defer file.Close()

	// Read first N bytes to detect encoding
	const sniffSize = 1024 * 10 // 10KB for detection
	buf := make([]byte, sniffSize)
	n, err := file.Read(buf)
	if err != nil && err != io.EOF {
		c.JSON(http.StatusInternalServerError, gin.H{"message": err.Error()})
		return
	}

	// Detect encoding
	detector := chardet.NewTextDetector()
	result, err := detector.DetectBest(buf[:n])
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to detect encoding"})
		return
	}

	_, err = file.Seek(0, io.SeekStart)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"message": "Failed to rewind file"})
		return
	}

	// Wrap reader based on encoding
	var reader io.Reader
	switch result.Charset {
	case "UTF-8":
		reader = file
	case "windows-1252":
		reader = transform.NewReader(file, charmap.Windows1252.NewDecoder())
	case "ISO-8859-1":
		reader = transform.NewReader(file, charmap.ISO8859_1.NewDecoder())
	default:
		c.JSON(http.StatusBadRequest, gin.H{"message": "Unsupported encoding: " + result.Charset})
		return
	}

	csvReader := csv.NewReader(reader)
	csvReader.Comma = rune(comma[0])

	records, err := csvReader.ReadAll()
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Failed to parse CSV"})
		return
	}

	var firstNameIndex, lastNameIndex, birthdayIndex, addressIndex, townIndex, zipIndex, phoneIndex, emailIndex int

	var message string
	for i, row := range records {
		if i < rowIndexI {
			continue
		} else if i == rowIndexI {
			for c, column := range row {
				switch column {
				case firstName:
					firstNameIndex = c
				case lastName:
					lastNameIndex = c
				case birthday:
					birthdayIndex = c
				case address:
					addressIndex = c
				case town:
					townIndex = c
				case zip:
					zipIndex = c
				case phone:
					phoneIndex = c
				case email:
					emailIndex = c
				}
			}
			continue
		}

		if row[firstNameIndex] == "" && row[lastNameIndex] == "" {
			continue
		}

		err := a.DbHandler.AddNewMember(models.Member{
			FirstName: row[firstNameIndex],
			LastName:  row[lastNameIndex],
			Birthday:  row[birthdayIndex],
			Address:   row[addressIndex],
			Town:      row[townIndex],
			Zip:       row[zipIndex],
			Phone:     row[phoneIndex],
			Email:     row[emailIndex],
		})

		if err != nil {
			message += "Row: " + fmt.Sprint(i) + " " + row[firstNameIndex] + " " + row[lastNameIndex] + " error: " + err.Error() + "\n"
		}
	}

	if message != "" {
		c.JSON(http.StatusBadRequest, gin.H{
			"message": message,
		})
		return
	}
	c.JSON(http.StatusOK, gin.H{
		"message": "CSV imported",
	})
}