package export

import (
	"os"
	"regexp"
	"strconv"
)

type FileOpts struct {
	fileName string
	limit    int
	row      int
}

func (f *FileOpts) slice() bool {
	f.row++
	if f.row > f.limit+1 { // +1 排除标题行
		f.row = 0
		return true
	}
	return false
}

type File struct {
	FileOpts

	param map[string]string
	index int
}

func NewFile(name string, limit int, param map[string]string) *File {
	return &File{
		FileOpts: FileOpts{
			fileName: name,
			limit:    limit,
		},
		param: param,
	}
}
func (f *File) SetIndex(index int) *File {
	f.index = index
	return f
}
func (f *File) SetRow(row int) *File {
	f.row = row
	return f
}

func (f *File) NextFile() *File {
	f.index++
	return f
}

func (f *File) FileName() string {
	m := regexp.MustCompile("({[a-zA-Z0-9]+})")
	name := m.ReplaceAllFunc([]byte(f.fileName), func(b []byte) []byte {
		field := string(b[1 : len(b)-1])

		if val, ok := f.param[field]; ok {
			return []byte(val)
		}
		return b
	})

	ex := regexp.MustCompile("(\\..*)")
	name = ex.ReplaceAllFunc(name, func(b []byte) []byte {
		i := []byte("_" + strconv.Itoa(f.index))
		ret := make([]byte, len(b)+len(i))
		copy(ret, i)
		copy(ret[len(i):], b)
		return ret
	})

	return string(name)
}

func (f *File) IsFileExist() bool {
	_, err := os.Stat(f.FileName())
	if err == nil {
		return true
	}

	if os.IsNotExist(err) {
		return false
	}

	return false
}