package utils

import (
	"bufio"
	"gitee.com/pheker/learn-go/tool/log"
	"io"
	"io/fs"
	"io/ioutil"
	"net/http"
	"os"
	"path/filepath"
	"strings"
)

func FileExist(path string) bool {
	_, err := os.Stat(path)
	return err == nil || os.IsExist(err)
}

// ReadLines 读取所有行
// filename 文件名
// sep 行分隔符
func ReadLines(filename string, sep string) []string {
	if !FileExist(filename) {
		return make([]string, 0)
	}

	b, _ := ioutil.ReadFile(filename)
	txt := string(b)

	lines := strings.Split(txt, sep)
	return lines
}

// ReadLine 按行读取
func ReadLine(filename string, lineHandler func(line string, lineno int) bool) {
	f, err := os.Open(filename)
	if err != nil {
		return
	}
	buf := bufio.NewReader(f)
	var lineno = 0
	for {
		line, _, eof := buf.ReadLine()
		if eof == io.EOF {
			break
		}
		nextLine := lineHandler(string(line), lineno)
		if !nextLine {
			break
		}
		lineno++
	}
}

func IsDir(path string) bool {
	s, err := os.Stat(path)
	if err != nil {
		return false
	}
	return s.IsDir()
}

func WriteLines(path string, lines []string) error {
	txt := strings.Join(lines, "\n")
	return WriteLine(path, txt, false)
}

func AppendLine(path string, line string) error {
	return WriteLine(path, line, true)
}

func WriteLine(path string, line string, append bool) error {
	var flag = os.O_RDWR | os.O_CREATE
	if append {
		flag |= os.O_APPEND
	}

	dir := filepath.Dir(path)
	exist := FileExist(dir)
	if !exist {
		os.MkdirAll(dir, 0766)
	}

	file, err := os.OpenFile(path, flag, 0766)
	if err != nil {
		log.Error(err.Error())
		return err
	}
	file.WriteString(line)
	file.Write([]byte{'\n'})
	return nil
}

func DownloadUrl(url string) string {
	client := http.Client{}
	html, err := client.Get(url)
	if err != nil || html.StatusCode != http.StatusOK {
		log.Errorf("下载html失败: %s\n", err)
	}
	content, readerr := ioutil.ReadAll(html.Body)
	if readerr != nil {
		return ""
	}
	return string(content)
}

type FileFilter func(path string, info fs.FileInfo) bool

func WalkFileList(fpath string, filter FileFilter) ([]Pair, error) {
	var files []Pair
	err := filepath.Walk(fpath, func(path string, info fs.FileInfo, err error) error {
		if !info.IsDir() && (filter == nil || filter(path, info)) {
			files = append(files, Pair{path, info})
		}
		return nil
	})
	return files, err
}