package main

import (
	"bufio"
	"crypto/tls"
	"encoding/json"
	"flag"
	"fmt"
	"io"
	"math/rand"
	"net/http"
	"os"
	"os/exec"
	"strings"

	"github.com/icelain/jokeapi"
)

const (
	host string = "irc.eu.libera.chat:6697"
	help string = `
botík obecný
https://git.h21.fun/h21/botik.git
Je v kanálu #h21 i v DM
Zdraví nově příchozí.
Příkazy:
!help - Zobraz nápovědu
!pozdrav - pozdraví
!fortune - řekne moudrost
!ftip - poví vtip
`
)

type ChuckJoke struct {
	Categories []interface{} `json:"categories"`
	Created_at string        `json:"created_at"`
	Icon_url   string        `json:"icon_url"`
	Id         string        `json:"id"`
	Update_at  string        `json:"update_at"`
	Url        string        `json:"url"`
	Value      string        `json:"value"`
}

func sendMsg(conn io.Writer, msg string, receiver string) {
	fmt.Fprintln(conn, "PRIVMSG "+receiver+" :"+msg)
}

func sendMultiline(conn io.Writer, msg string, receiver string) {
	for _, l := range strings.Split(strings.Trim(msg, "\n"), "\n") {
		sendMsg(conn, l, receiver)
	}
}

func main() {
	// flags parse
	var debug bool
	flag.BoolVar(&debug, "D", false, "Print debug messages.")
	flag.Parse()
	// IRC init
	conn, err := tls.Dial("tcp", host, &tls.Config{RootCAs: nil})
	if err != nil {
		panic("Failed to connect")
	}
	defer conn.Close()
	reader := bufio.NewReader(conn)
	fmt.Fprintln(conn, "USER h21-botik botik h21  :botik obecny")
	fmt.Fprintln(conn, "NICK h21-botik")
	fmt.Fprintln(conn, "JOIN #h21")
	// joke init
	api := jokeapi.New()
	api.SetLang("en")
	// IRC
	for {
		in, _ := reader.ReadString('\n')
		words := strings.Fields(in)
		if debug {
			fmt.Fprintln(os.Stderr, words)
		}
		who := strings.Split(words[0], "!")[0][1:]
		if who == "botik" {
			continue
		}
		switch words[1] {
		case "JOIN":
			sendMsg(conn, "Vítej "+who, words[2])
		case "PRIVMSG":
			var receiver string
			if []rune(words[2])[0] == '#' {
				receiver = words[2]
			} else {
				receiver = who
			}
			switch words[3][1:] {
			case "!help":
				sendMultiline(conn, help, receiver)
			case "!pozdrav":
				sendMsg(conn, "Ahoj "+who, receiver)
			case "!fortune":
				msg, _ := exec.Command("fortune", "cs").Output()
				fmt.Println(string(msg))
				sendMultiline(conn, string(msg), receiver)
			case "!ftip":
				if rand.Intn(2) == 0 {
					res, err := http.Get("https://api.chucknorris.io/jokes/random")
					if err != nil {
						fmt.Println(err)
					}
					var parse ChuckJoke
					bodyStr, err := io.ReadAll(res.Body)
					res.Body.Close()
					if err != nil {
						fmt.Println(err)
					}
					err = json.Unmarshal(bodyStr, &parse)
					if err != nil {
						fmt.Println(err)
					}
					sendMultiline(conn, parse.Value, receiver)
				} else {
					ftip, _ := api.Fetch()
					for _, l := range ftip.Joke {
						sendMultiline(conn, l, receiver)
					}
				}
			}
		}
		if words[0] == "PING" {
			fmt.Fprintln(conn, "PONG "+words[1])
		}
	}
}