package irclogs

import (
	"database/sql"
	"fmt"
	"log"
	"slices"
	"strings"
)

type IRCMessage struct {
	Tags    map[string]string
	Nick    string
	Command string
	Params  []string
}

func ParseIRCMessage(message string) IRCMessage {
	message = strings.TrimRight(message, "\r\n")
	msg := IRCMessage{
		Tags: make(map[string]string),
	}

	if strings.HasPrefix(message, "@") {
		end := strings.IndexByte(message, ' ')
		rawTags := message[1:end]

		for _, tag := range strings.Split(rawTags, ";") {
			parts := strings.SplitN(tag, "=", 2)
			if len(parts) == 2 {
				msg.Tags[parts[0]] = parts[1]
			} else {
				msg.Tags[parts[0]] = "true"
			}
		}

		message = message[end+1:]
	}

	if strings.HasPrefix(message, ":") {
		end := strings.IndexByte(message, ' ')
		prefix := message[1:end]
		if bang := strings.IndexByte(prefix, '!'); bang != -1 {
			msg.Nick = prefix[:bang]
		}
		message = message[end+1:]
	}

	parts := strings.Split(message, " ")
	if len(parts) == 0 {
		return msg
	}

	msg.Command = parts[0]
	parts = parts[1:]

	for i := 0; i < len(parts); i++ {
		if len(parts[i]) == 0 {
			continue
		}
		if parts[i][0] == ':' {
			param := strings.Join(parts[i:], " ")[1:]
			msg.Params = append(msg.Params, param)
			break
		}
		msg.Params = append(msg.Params, parts[i])
	}

	return msg
}

func (m *IRCMessage) Save(db *sql.DB, serverId int) {
	var roomId int
	var roomDepart sql.NullTime
	err := db.QueryRow(
		"SELECT id, departed_at FROM rooms WHERE name = ? AND server_id = ?",
		m.Params[0], serverId,
	).Scan(&roomId, &roomDepart)
	if err != nil || roomDepart.Valid {
		return
	}

	var userId int64
	var userDepart sql.NullTime
	err = db.QueryRow(
		"SELECT id, departed_at FROM users WHERE server_id = ? AND nick = ?",
		serverId, m.Nick,
	).Scan(&userId, &userDepart)
	if err == sql.ErrNoRows {
		res, err := db.Exec("INSERT INTO users(server_id, nick) VALUES (?, ?)", serverId, m.Nick)
		if err != nil {
			log.Panicf("Failed to create a new user: %v\n", err)
		}
		userId, _ = res.LastInsertId()
	} else if err != nil {
		log.Panicf("Failed to get a user: %v\n", err)
	} else if userDepart.Valid {
		return
	}

	tags := sql.NullString{
		String: "",
		Valid:  len(m.Tags) > 0,
	}
	for k, v := range m.Tags {
		tags.String += fmt.Sprintf("%s=%s;", k, v)
	}
	if len(tags.String) > 0 {
		tags.String = tags.String[:len(tags.String)-1]
	}

	if len(m.Params) > 0 && m.Params[0][0] == '#' {
		m.Params = slices.Delete(m.Params, 0, 1)
	}

	params := sql.NullString{
		String: strings.Join(m.Params, " "),
		Valid:  len(m.Params) > 0,
	}

	_, err = db.Exec("INSERT INTO messages(room_id, user_id, command, params, tags) VALUES (?, ?, ?, ?, ?)",
		roomId, userId, m.Command, params, tags)

	if err != nil {
		log.Panicf("Failed to add a message: %v\n", err)
	}
}