package attach

import (
	"io"
	"os"

	"b612.me/starlog"
	"github.com/spf13/cobra"
)

var Cmd = &cobra.Command{
	Use:   "attach",
	Short: "合并多个文件",
	Long:  "合并多个文件",
	Run: func(this *cobra.Command, args []string) {
		src, _ := this.Flags().GetStringArray("src")
		out, _ := this.Flags().GetString("out")
		if len(src) < 2 || out == "" {
			starlog.Criticalln("请输入至少2个输入路径，一个输出路径")
			os.Exit(1)
		}
		os.Exit(runAttach(src, out))
	},
}

func runAttach(src []string, out string) int {
	fpOut, err := os.Create(out)
	if err != nil {
		starlog.Errorln("Err:无法创建输出文件！", err)
		return 2
	}
	defer fpOut.Close()
	for _, file := range src {
		fpFile, err := os.OpenFile(file, os.O_RDONLY, 0644)
		if err != nil {
			starlog.Errorln("Err:Cannot Openfile:", err)
			return 3
		}
		stats, err := fpFile.Stat()
		if err != nil {
			starlog.Errorln("Err:Cannot Get File Stats:", err)
			return 4
		}
		if stats.Size() == 0 {
			starlog.Warningf("文件:%s为空文件，跳过！\n", stats.Name())
			continue
		}
		buf := make([]byte, 65535)
		sumAll := 0
		for {
			n, err := fpFile.Read(buf)
			if err != nil && err != io.EOF {
				starlog.Errorln("Err:Error Occured While ReadFile:", err)
				fpFile.Close()
				return 5
			}
			sumAll += n
			_, errW := fpOut.Write(buf[:n])
			if errW != nil {
				starlog.Errorln("Error While Write Data to OutFile", errW)
				return 6
			}
			starlog.StdPrintf([]starlog.Attr{starlog.FgGreen}, "文件%s，已完成：%.2f%%\r", stats.Name(), (float64(sumAll) / float64(stats.Size()) * 100.0000))
			if err == io.EOF {
				starlog.StdPrintf([]starlog.Attr{starlog.FgGreen}, "文件：%v，已完成：100.00%% \n", stats.Name())
				fpFile.Close()
				break
			}
		}
	}
	starlog.StdPrintln([]starlog.Attr{starlog.FgGreen}, "Ok!文件合并完成")
	return 0
}

func init() {
	Cmd.Flags().StringArrayP("src", "s", []string{}, "源文件路径")
	Cmd.Flags().StringP("out", "o", "", "输出文件路径")
}