package main

import (
	"flag"
	"fmt"
	"strings"

	"github.com/nxadm/tail"
)

// ParseChat Parses a string, returns the payload of the chat
// *sigh*
// This took effing forever to get right.
// "Lets start with Regex, cannot go wrong".
// You have this string:
// ��[ 2022.02.09 10:05:43 ] Kaysee Guru > EX-GBT clr nd
// Cool. Looks easy.
// .*\[ (.*?) (.*?) \] (.*?) > (.*)
// regex101.com says its good
// And no matter what I do just does not work for some magical reason.
//
// Lets do this with splitting by space and compare it with that. Do a bunch of ifs, it works in test aaaaaand....
// It doesn't work.
//
// By now I have a somewhat reliable version, but it fails to look for the word MOTD.
// I should prolly look into runes()
// This is terrible
func ParseChat(chatline string) (LineDate string, LineTime string, LineUser string, Payload []string) {
	logLine := chatline[3:]

	//var LineDate string
	//var LineTime string
	//var LineUser string
	var LinePayload string
	//var Payload []string
	var splitpos int

	splitpos = strings.Index(logLine, ">")
	LineDate = logLine[4:24]
	LineTime = logLine[24:42]
	LineUser = logLine[46 : splitpos-2]
	LinePayload = logLine[splitpos+4:]
	LinePayload = shorten(LinePayload)
	Payload = strings.Fields(LinePayload)

	//fmt.Println(logLine)
	//fmt.Println(LineDate)
	//fmt.Println(LineTime)
	//fmt.Println(LineUser)
	//fmt.Println(splitpos)
	//fmt.Println(LinePayload)
	//fmt.Println(Payload)

	return
}

func shorten(payload string) (logLine string) {
	runes := []rune(payload)
	for pos, char := range runes {
		if pos%2 == 0 && char != 13 {
			logLine = logLine + string(char)
		}
	}
	return
}

// CompareElements Compares a log msg with systems we wish to track
func CompareElements(alerts []string, payload []string) bool {

	for _, word := range payload {
		for _, alert := range alerts {

			if strings.EqualFold(word, alert) {
				//fmt.Println("Found (EF): ", alert, "in", word)
				return true
			} //else {
			//	fmt.Println(word, "!=", alert)
			//}

			// In the odd case somebody links "C-V6DQ*"
			if len(word) > 6 {
				//alert = alert[:len(word)]
				word = word[:6]
			}

			// In case of partials like "C-V"
			if len(word) < 6 && len(word) >= 3 {
				//word = word[:5]
				alert = alert[:len(word)]
			}

			if strings.EqualFold(word, alert) {
				//fmt.Println("Found: ", alert, "in", word)
				return true
			}
		}
	}
	return false
}

// playBeep Play a beep
// Honestly, I tried to play alert.mp3, but after two executions I got a segfault and thought 0x07 it is!
func playBeep() {
	fmt.Print("\a")
}

func main() {

	// Deal with parameters first.
	LogLocation := flag.String("l", "", "Location of the log-file to track.")
	LogSystemsRaw := flag.String("s", "jita,Perimeter,New Caldari,Sobaseki", "comma-seperated list of systems")
	//LogAlarm := flag.String("a", "alert.mp3", "Audio file to play when an alert needs to be triggered")
	flag.Parse()

	// Split the CSV string into different parts
	LogSystems := strings.Split(*LogSystemsRaw, ",")

	// Do the main loop and start parsing the logfiles
	t, err := tail.TailFile(*LogLocation, tail.Config{Follow: true})
	if err != nil {
		panic(err)
	}

	for line := range t.Lines {
		// Cast a line to a text, trim the trash
		logLine := string(line.Text)
		logLine = strings.Trim(logLine, "\n")

		// Figure out if this is a message we want to deal with
		// > is critical in this regard because it is the start of the message
		// and everything behind it until it hits ] is the username
		splitpos := strings.Index(logLine, ">")
		if -1 == splitpos {
			continue
		}

		// Somehow I cannot filter out this stuff.
		// EVE System > Channel MOTD
		LineDate, LineTime, LineUser, Payload := ParseChat(logLine)

		if CompareElements(LogSystems, Payload) {
			playBeep()
			fmt.Println("On", LineDate, "at", LineTime, "", LineUser, "posted", Payload)
		}

	}

}