package check

import (
	"fmt"
	"go/slack-bot/pkg/notify"
	"regexp"
	"strconv"
	"strings"
)

const dfMessage = "disk check"

//DfChecker df command implementation of AdvancedChecker
type DfChecker struct {
	CliChecker
	pourcentRegexMatcher *regexp.Regexp
}

type DfStdout []DfStdoutLine
type DfStdoutLine struct {
	Filesystem,
	Size,
	Used,
	Available string
	PourcentUsed int
	Mounted      string
}

//DfParameter df check configuration
type DfParameter struct {
	FileSystemName   string `hcl:"fs_name"`
	CriticalPourcent int    `hcl:"critical"`
}

//NewDfChecker build new checker for df command
func NewDfChecker() *DfChecker {
	return &DfChecker{
		CliChecker: CliChecker{
			alertingMessage: dfMessage,
			command:         []string{"sh", "-c", "df -P | grep -v 'auto_home'"},
		},
		pourcentRegexMatcher: regexp.MustCompile(`(?P<value>.*)%`),
	}
}

//Parse df command stdout
func (dc *DfChecker) Parse(stdout string) interface{} {
	var dfOut DfStdout

	for _, line := range strings.Split(stdout, "\n")[1:] {
		if strings.TrimSpace(line) == "" {
			continue
		}

		var cleanedColumns []string
		for _, col := range strings.Split(line, " ") {
			if v := strings.TrimSpace(col); v != "" {
				cleanedColumns = append(cleanedColumns, v)
			}
		}

		valueIndex := dc.pourcentRegexMatcher.SubexpIndex("value")
		log.Printf("df column : %+v\n", cleanedColumns)
		v, err := strconv.Atoi(dc.pourcentRegexMatcher.FindStringSubmatch(cleanedColumns[4])[valueIndex])
		if err != nil {
			v = -1
		}
		// extract pourcent used from columns
		dfOut = append(dfOut, DfStdoutLine{
			Filesystem:   cleanedColumns[0],
			Size:         cleanedColumns[1],
			Used:         cleanedColumns[2],
			Available:    cleanedColumns[3],
			PourcentUsed: v,
			Mounted:      cleanedColumns[len(cleanedColumns)-1],
		})
	}
	return dfOut
}

//FileSystemUsedCheck take dfStdout and check if filesystem is full over than criticalPourcent value
func (dc *DfChecker) FileSystemUsedCheck(dfOut DfStdout, param DfParameter) notify.Message {
	message := notify.Message{
		ShouldNotify: false,
	}
	for _, line := range dfOut {
		if line.Filesystem == param.FileSystemName {
			if line.PourcentUsed > param.CriticalPourcent {
				text := fmt.Sprintf("%s : fs '%s' critial %d%%, used %d%% \n", dc.alertingMessage, line.Filesystem, param.CriticalPourcent, line.PourcentUsed)
				message = notify.Message{
					Content:      text,
					ShouldNotify: true,
				}
			}
		}
	}
	return message
}