Vendor github.com/lrstanley/girc

1 files changed, 550 insertions, 0 deletions

diff --git a/vendor/github.com/lrstanley/girc/event.go b/vendor/github.com/lrstanley/girc/event.go
new file mode 100644
index 00000000..77d9b45e
--- /dev/null
+++ b/vendor/github.com/lrstanley/girc/event.go
@@ -0,0 +1,550 @@
+// Copyright (c) Liam Stanley <me@liamstanley.io>. All rights reserved. Use
+// of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+package girc
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+)
+
+const (
+	eventSpace byte = 0x20 // Separator.
+	maxLength       = 510  // Maximum length is 510 (2 for line endings).
+)
+
+// cutCRFunc is used to trim CR characters from prefixes/messages.
+func cutCRFunc(r rune) bool {
+	return r == '\r' || r == '\n'
+}
+
+// Event represents an IRC protocol message, see RFC1459 section 2.3.1
+//
+//    <message>  :: [':' <prefix> <SPACE>] <command> <params> <crlf>
+//    <prefix>   :: <servername> | <nick> ['!' <user>] ['@' <host>]
+//    <command>  :: <letter>{<letter>} | <number> <number> <number>
+//    <SPACE>    :: ' '{' '}
+//    <params>   :: <SPACE> [':' <trailing> | <middle> <params>]
+//    <middle>   :: <Any *non-empty* sequence of octets not including SPACE or NUL
+//                   or CR or LF, the first of which may not be ':'>
+//    <trailing> :: <Any, possibly empty, sequence of octets not including NUL or
+//                   CR or LF>
+//    <crlf>     :: CR LF
+type Event struct {
+	Source        *Source  `json:"source"`         // The source of the event.
+	Tags          Tags     `json:"tags"`           // IRCv3 style message tags. Only use if network supported.
+	Command       string   `json:"command"`        // the IRC command, e.g. JOIN, PRIVMSG, KILL.
+	Params        []string `json:"params"`         // parameters to the command. Commonly nickname, channel, etc.
+	Trailing      string   `json:"trailing"`       // any trailing data. e.g. with a PRIVMSG, this is the message text.
+	EmptyTrailing bool     `json:"empty_trailing"` // if true, trailing prefix (:) will be added even if Event.Trailing is empty.
+	Sensitive     bool     `json:"sensitive"`      // if the message is sensitive (e.g. and should not be logged).
+}
+
+// ParseEvent takes a string and attempts to create a Event struct.
+//
+// Returns nil if the Event is invalid.
+func ParseEvent(raw string) (e *Event) {
+	// Ignore empty events.
+	if raw = strings.TrimFunc(raw, cutCRFunc); len(raw) < 2 {
+		return nil
+	}
+
+	var i, j int
+	e = &Event{}
+
+	if raw[0] == prefixTag {
+		// Tags end with a space.
+		i = strings.IndexByte(raw, eventSpace)
+
+		if i < 2 {
+			return nil
+		}
+
+		e.Tags = ParseTags(raw[1:i])
+		raw = raw[i+1:]
+	}
+
+	if raw[0] == messagePrefix {
+		// Prefix ends with a space.
+		i = strings.IndexByte(raw, eventSpace)
+
+		// Prefix string must not be empty if the indicator is present.
+		if i < 2 {
+			return nil
+		}
+
+		e.Source = ParseSource(raw[1:i])
+
+		// Skip space at the end of the prefix.
+		i++
+	}
+
+	// Find end of command.
+	j = i + strings.IndexByte(raw[i:], eventSpace)
+
+	if j < i {
+		// If there are no proceeding spaces, it's the only thing specified.
+		e.Command = strings.ToUpper(raw[i:])
+		return e
+	}
+
+	e.Command = strings.ToUpper(raw[i:j])
+
+	// Skip the space after the command.
+	j++
+
+	// Check if and where the trailing text is within the incoming line.
+	var lastIndex, trailerIndex int
+	for {
+		// We must loop through, as it's possible that the first message
+		// prefix is not actually what we want. (e.g, colons are commonly
+		// used within ISUPPORT to delegate things like CHANLIMIT or TARGMAX.)
+		lastIndex = trailerIndex
+		trailerIndex = strings.IndexByte(raw[j+lastIndex:], messagePrefix)
+
+		if trailerIndex == -1 {
+			// No trailing argument found, assume the rest is just params.
+			e.Params = strings.Split(raw[j:], string(eventSpace))
+			return e
+		}
+
+		// This means we found a prefix that was proceeded by a space, and
+		// it's good to assume this is the start of trailing text to the line.
+		if raw[j+lastIndex+trailerIndex-1] == eventSpace {
+			i = lastIndex + trailerIndex
+			break
+		}
+
+		// Keep looping through until we either can't find any more prefixes,
+		// or we find the one we want.
+		trailerIndex += lastIndex + 1
+	}
+
+	// Set i to that of the substring we were using before, and where the
+	// trailing prefix is.
+	i = j + i
+
+	// Check if we need to parse arguments. If so, take everything after the
+	// command, and right before the trailing prefix, and cut it up.
+	if i > j {
+		e.Params = strings.Split(raw[j:i-1], string(eventSpace))
+	}
+
+	e.Trailing = raw[i+1:]
+
+	// We need to re-encode the trailing argument even if it was empty.
+	if len(e.Trailing) <= 0 {
+		e.EmptyTrailing = true
+	}
+
+	return e
+}
+
+// Copy makes a deep copy of a given event, for use with allowing untrusted
+// functions/handlers edit the event without causing potential issues with
+// other handlers.
+func (e *Event) Copy() *Event {
+	if e == nil {
+		return nil
+	}
+
+	newEvent := &Event{
+		Command:       e.Command,
+		Trailing:      e.Trailing,
+		EmptyTrailing: e.EmptyTrailing,
+		Sensitive:     e.Sensitive,
+	}
+
+	// Copy Source field, as it's a pointer and needs to be dereferenced.
+	if e.Source != nil {
+		newEvent.Source = e.Source.Copy()
+	}
+
+	// Copy Params in order to dereference as well.
+	if e.Params != nil {
+		newEvent.Params = make([]string, len(e.Params))
+		copy(newEvent.Params, e.Params)
+	}
+
+	// Copy tags as necessary.
+	if e.Tags != nil {
+		newEvent.Tags = Tags{}
+		for k, v := range e.Tags {
+			newEvent.Tags[k] = v
+		}
+	}
+
+	return newEvent
+}
+
+// Len calculates the length of the string representation of event. Note that
+// this will return the true length (even if longer than what IRC supports),
+// which may be useful if you are trying to check and see if a message is
+// too long, to trim it down yourself.
+func (e *Event) Len() (length int) {
+	if e.Tags != nil {
+		// Include tags and trailing space.
+		length = e.Tags.Len() + 1
+	}
+	if e.Source != nil {
+		// Include prefix and trailing space.
+		length += e.Source.Len() + 2
+	}
+
+	length += len(e.Command)
+
+	if len(e.Params) > 0 {
+		length += len(e.Params)
+
+		for i := 0; i < len(e.Params); i++ {
+			length += len(e.Params[i])
+		}
+	}
+
+	if len(e.Trailing) > 0 || e.EmptyTrailing {
+		// Include prefix and space.
+		length += len(e.Trailing) + 2
+	}
+
+	return
+}
+
+// Bytes returns a []byte representation of event. Strips all newlines and
+// carriage returns.
+//
+// Per RFC2812 section 2.3, messages should not exceed 512 characters in
+// length. This method forces that limit by discarding any characters
+// exceeding the length limit.
+func (e *Event) Bytes() []byte {
+	buffer := new(bytes.Buffer)
+
+	// Tags.
+	if e.Tags != nil {
+		e.Tags.writeTo(buffer)
+	}
+
+	// Event prefix.
+	if e.Source != nil {
+		buffer.WriteByte(messagePrefix)
+		e.Source.writeTo(buffer)
+		buffer.WriteByte(eventSpace)
+	}
+
+	// Command is required.
+	buffer.WriteString(e.Command)
+
+	// Space separated list of arguments.
+	if len(e.Params) > 0 {
+		buffer.WriteByte(eventSpace)
+		buffer.WriteString(strings.Join(e.Params, string(eventSpace)))
+	}
+
+	if len(e.Trailing) > 0 || e.EmptyTrailing {
+		buffer.WriteByte(eventSpace)
+		buffer.WriteByte(messagePrefix)
+		buffer.WriteString(e.Trailing)
+	}
+
+	// We need the limit the buffer length.
+	if buffer.Len() > (maxLength) {
+		buffer.Truncate(maxLength)
+	}
+
+	out := buffer.Bytes()
+
+	// Strip newlines and carriage returns.
+	for i := 0; i < len(out); i++ {
+		if out[i] == 0x0A || out[i] == 0x0D {
+			out = append(out[:i], out[i+1:]...)
+			i-- // Decrease the index so we can pick up where we left off.
+		}
+	}
+
+	return out
+}
+
+// String returns a string representation of this event. Strips all newlines
+// and carriage returns.
+func (e *Event) String() string {
+	return string(e.Bytes())
+}
+
+// Pretty returns a prettified string of the event. If the event doesn't
+// support prettification, ok is false. Pretty is not just useful to make
+// an event prettier, but also to filter out events that most don't visually
+// see in normal IRC clients. e.g. most clients don't show WHO queries.
+func (e *Event) Pretty() (out string, ok bool) {
+	if e.Sensitive {
+		return "", false
+	}
+
+	if e.Command == ERROR {
+		return fmt.Sprintf("[*] an error occurred: %s", e.Trailing), true
+	}
+
+	if e.Source == nil {
+		if e.Command != PRIVMSG && e.Command != NOTICE {
+			return "", false
+		}
+
+		if len(e.Params) > 0 && len(e.Trailing) > 0 {
+			return fmt.Sprintf("[>] writing %s [%s]: %s", strings.ToLower(e.Command), strings.Join(e.Params, ", "), e.Trailing), true
+		} else if len(e.Params) > 0 {
+			return fmt.Sprintf("[>] writing %s [%s]", strings.ToLower(e.Command), strings.Join(e.Params, ", ")), true
+		} else if len(e.Trailing) > 0 {
+			return fmt.Sprintf("[>] writing %s: %s", strings.ToLower(e.Command), e.Trailing), true
+		}
+
+		return "", false
+	}
+
+	if e.Command == INITIALIZED {
+		return fmt.Sprintf("[*] connection to %s initialized", e.Trailing), true
+	}
+
+	if e.Command == CONNECTED {
+		return fmt.Sprintf("[*] successfully connected to %s", e.Trailing), true
+	}
+
+	if (e.Command == PRIVMSG || e.Command == NOTICE) && len(e.Params) > 0 {
+		if ctcp := decodeCTCP(e); ctcp != nil {
+			if ctcp.Reply {
+				return
+			}
+
+			return fmt.Sprintf("[*] CTCP query from %s: %s%s", ctcp.Source.Name, ctcp.Command, " "+ctcp.Text), true
+		}
+		return fmt.Sprintf("[%s] (%s) %s", strings.Join(e.Params, ","), e.Source.Name, e.Trailing), true
+	}
+
+	if e.Command == RPL_MOTD || e.Command == RPL_MOTDSTART ||
+		e.Command == RPL_WELCOME || e.Command == RPL_YOURHOST ||
+		e.Command == RPL_CREATED || e.Command == RPL_LUSERCLIENT {
+		return "[*] " + e.Trailing, true
+	}
+
+	if e.Command == JOIN && len(e.Params) > 0 {
+		return fmt.Sprintf("[*] %s (%s) has joined %s", e.Source.Name, e.Source.Host, e.Params[0]), true
+	}
+
+	if e.Command == PART && len(e.Params) > 0 {
+		return fmt.Sprintf("[*] %s (%s) has left %s (%s)", e.Source.Name, e.Source.Host, e.Params[0], e.Trailing), true
+	}
+
+	if e.Command == QUIT {
+		return fmt.Sprintf("[*] %s has quit (%s)", e.Source.Name, e.Trailing), true
+	}
+
+	if e.Command == KICK && len(e.Params) == 2 {
+		return fmt.Sprintf("[%s] *** %s has kicked %s: %s", e.Params[0], e.Source.Name, e.Params[1], e.Trailing), true
+	}
+
+	if e.Command == NICK && len(e.Params) == 1 {
+		return fmt.Sprintf("[*] %s is now known as %s", e.Source.Name, e.Params[0]), true
+	}
+
+	if e.Command == TOPIC && len(e.Params) > 0 {
+		return fmt.Sprintf("[%s] *** %s has set the topic to: %s", e.Params[len(e.Params)-1], e.Source.Name, e.Trailing), true
+	}
+
+	if e.Command == MODE && len(e.Params) > 2 {
+		return fmt.Sprintf("[%s] *** %s set modes: %s", e.Params[0], e.Source.Name, strings.Join(e.Params[1:], " ")), true
+	}
+
+	if e.Command == CAP_AWAY {
+		if len(e.Trailing) > 0 {
+			return fmt.Sprintf("[*] %s is now away: %s", e.Source.Name, e.Trailing), true
+		}
+
+		return fmt.Sprintf("[*] %s is no longer away", e.Source.Name), true
+	}
+
+	if e.Command == CAP_CHGHOST && len(e.Params) == 2 {
+		return fmt.Sprintf("[*] %s has changed their host to %s (was %s)", e.Source.Name, e.Params[1], e.Source.Host), true
+	}
+
+	if e.Command == CAP_ACCOUNT && len(e.Params) == 1 {
+		if e.Params[0] == "*" {
+			return fmt.Sprintf("[*] %s has become un-authenticated", e.Source.Name), true
+		}
+
+		return fmt.Sprintf("[*] %s has authenticated for account: %s", e.Source.Name, e.Params[0]), true
+	}
+
+	if e.Command == RPL_TOPIC && len(e.Params) > 0 && len(e.Trailing) > 0 {
+		return fmt.Sprintf("[*] topic for %s is: %s", e.Params[len(e.Params)-1], e.Trailing), true
+	}
+
+	return "", false
+}
+
+// IsAction checks to see if the event is a PRIVMSG, and is an ACTION (/me).
+func (e *Event) IsAction() bool {
+	if e.Source == nil || e.Command != PRIVMSG || len(e.Trailing) < 9 {
+		return false
+	}
+
+	if !strings.HasPrefix(e.Trailing, "\001ACTION") || e.Trailing[len(e.Trailing)-1] != ctcpDelim {
+		return false
+	}
+
+	return true
+}
+
+// IsFromChannel checks to see if a message was from a channel (rather than
+// a private message).
+func (e *Event) IsFromChannel() bool {
+	if e.Source == nil || e.Command != PRIVMSG || len(e.Params) < 1 {
+		return false
+	}
+
+	if !IsValidChannel(e.Params[0]) {
+		return false
+	}
+
+	return true
+}
+
+// IsFromUser checks to see if a message was from a user (rather than a
+// channel).
+func (e *Event) IsFromUser() bool {
+	if e.Source == nil || e.Command != PRIVMSG || len(e.Params) < 1 {
+		return false
+	}
+
+	if !IsValidNick(e.Params[0]) {
+		return false
+	}
+
+	return true
+}
+
+// StripAction returns the stripped version of the action encoding from a
+// PRIVMSG ACTION (/me).
+func (e *Event) StripAction() string {
+	if !e.IsAction() {
+		return e.Trailing
+	}
+
+	return e.Trailing[8 : len(e.Trailing)-1]
+}
+
+const (
+	messagePrefix byte = 0x3A // ":" -- prefix or last argument
+	prefixIdent   byte = 0x21 // "!" -- username
+	prefixHost    byte = 0x40 // "@" -- hostname
+)
+
+// Source represents the sender of an IRC event, see RFC1459 section 2.3.1.
+// <servername> | <nick> [ '!' <user> ] [ '@' <host> ]
+type Source struct {
+	// Name is the nickname, server name, or service name.
+	Name string `json:"name"`
+	// Ident is commonly known as the "user".
+	Ident string `json:"ident"`
+	// Host is the hostname or IP address of the user/service. Is not accurate
+	// due to how IRC servers can spoof hostnames.
+	Host string `json:"host"`
+}
+
+// Copy returns a deep copy of Source.
+func (s *Source) Copy() *Source {
+	if s == nil {
+		return nil
+	}
+
+	newSource := &Source{
+		Name:  s.Name,
+		Ident: s.Ident,
+		Host:  s.Host,
+	}
+
+	return newSource
+}
+
+// ParseSource takes a string and attempts to create a Source struct.
+func ParseSource(raw string) (src *Source) {
+	src = new(Source)
+
+	user := strings.IndexByte(raw, prefixIdent)
+	host := strings.IndexByte(raw, prefixHost)
+
+	switch {
+	case user > 0 && host > user:
+		src.Name = raw[:user]
+		src.Ident = raw[user+1 : host]
+		src.Host = raw[host+1:]
+	case user > 0:
+		src.Name = raw[:user]
+		src.Ident = raw[user+1:]
+	case host > 0:
+		src.Name = raw[:host]
+		src.Host = raw[host+1:]
+	default:
+		src.Name = raw
+	}
+
+	return src
+}
+
+// Len calculates the length of the string representation of prefix
+func (s *Source) Len() (length int) {
+	length = len(s.Name)
+	if len(s.Ident) > 0 {
+		length = 1 + length + len(s.Ident)
+	}
+	if len(s.Host) > 0 {
+		length = 1 + length + len(s.Host)
+	}
+
+	return
+}
+
+// Bytes returns a []byte representation of source.
+func (s *Source) Bytes() []byte {
+	buffer := new(bytes.Buffer)
+	s.writeTo(buffer)
+
+	return buffer.Bytes()
+}
+
+// String returns a string representation of source.
+func (s *Source) String() (out string) {
+	out = s.Name
+	if len(s.Ident) > 0 {
+		out = out + string(prefixIdent) + s.Ident
+	}
+	if len(s.Host) > 0 {
+		out = out + string(prefixHost) + s.Host
+	}
+
+	return
+}
+
+// IsHostmask returns true if source looks like a user hostmask.
+func (s *Source) IsHostmask() bool {
+	return len(s.Ident) > 0 && len(s.Host) > 0
+}
+
+// IsServer returns true if this source looks like a server name.
+func (s *Source) IsServer() bool {
+	return len(s.Ident) <= 0 && len(s.Host) <= 0
+}
+
+// writeTo is an utility function to write the source to the bytes.Buffer
+// in Event.String().
+func (s *Source) writeTo(buffer *bytes.Buffer) {
+	buffer.WriteString(s.Name)
+	if len(s.Ident) > 0 {
+		buffer.WriteByte(prefixIdent)
+		buffer.WriteString(s.Ident)
+	}
+	if len(s.Host) > 0 {
+		buffer.WriteByte(prefixHost)
+		buffer.WriteString(s.Host)
+	}
+
+	return
+}