mautrix-whatsapp/formatting.go

198 lines
7.2 KiB
Go

// mautrix-whatsapp - A Matrix-WhatsApp puppeting bridge.
// Copyright (C) 2023 Tulir Asokan
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
package main
import (
"fmt"
"html"
"regexp"
"sort"
"strings"
"go.mau.fi/whatsmeow/types"
"golang.org/x/exp/slices"
"maunium.net/go/mautrix/event"
"maunium.net/go/mautrix/format"
"maunium.net/go/mautrix/id"
)
var italicRegex = regexp.MustCompile("([\\s>~*]|^)_(.+?)_([^a-zA-Z\\d]|$)")
var boldRegex = regexp.MustCompile("([\\s>_~]|^)\\*(.+?)\\*([^a-zA-Z\\d]|$)")
var strikethroughRegex = regexp.MustCompile("([\\s>_*]|^)~(.+?)~([^a-zA-Z\\d]|$)")
var codeBlockRegex = regexp.MustCompile("```(?:.|\n)+?```")
var inlineURLRegex = regexp.MustCompile(`\[(.+?)]\((.+?)\)`)
const mentionedJIDsContextKey = "fi.mau.whatsapp.mentioned_jids"
const allowedMentionsContextKey = "fi.mau.whatsapp.allowed_mentions"
type Formatter struct {
bridge *WABridge
matrixHTMLParser *format.HTMLParser
waReplString map[*regexp.Regexp]string
waReplFunc map[*regexp.Regexp]func(string) string
waReplFuncText map[*regexp.Regexp]func(string) string
}
func NewFormatter(bridge *WABridge) *Formatter {
formatter := &Formatter{
bridge: bridge,
matrixHTMLParser: &format.HTMLParser{
TabsToSpaces: 4,
Newline: "\n",
PillConverter: func(displayname, mxid, eventID string, ctx format.Context) string {
allowedMentions, _ := ctx.ReturnData[allowedMentionsContextKey].(map[types.JID]bool)
if mxid[0] == '@' {
var jid types.JID
if puppet := bridge.GetPuppetByMXID(id.UserID(mxid)); puppet != nil {
jid = puppet.JID
} else if user := bridge.GetUserByMXIDIfExists(id.UserID(mxid)); user != nil {
jid = user.JID.ToNonAD()
}
if !jid.IsEmpty() && (allowedMentions == nil || allowedMentions[jid]) {
if allowedMentions == nil {
jids, ok := ctx.ReturnData[mentionedJIDsContextKey].([]string)
if !ok {
ctx.ReturnData[mentionedJIDsContextKey] = []string{jid.String()}
} else {
ctx.ReturnData[mentionedJIDsContextKey] = append(jids, jid.String())
}
}
return "@" + jid.User
}
}
return displayname
},
BoldConverter: func(text string, _ format.Context) string { return fmt.Sprintf("*%s*", text) },
ItalicConverter: func(text string, _ format.Context) string { return fmt.Sprintf("_%s_", text) },
StrikethroughConverter: func(text string, _ format.Context) string { return fmt.Sprintf("~%s~", text) },
MonospaceConverter: func(text string, _ format.Context) string { return fmt.Sprintf("```%s```", text) },
MonospaceBlockConverter: func(text, language string, _ format.Context) string { return fmt.Sprintf("```%s```", text) },
},
waReplString: map[*regexp.Regexp]string{
italicRegex: "$1<em>$2</em>$3",
boldRegex: "$1<strong>$2</strong>$3",
strikethroughRegex: "$1<del>$2</del>$3",
},
}
formatter.waReplFunc = map[*regexp.Regexp]func(string) string{
codeBlockRegex: func(str string) string {
str = str[3 : len(str)-3]
if strings.ContainsRune(str, '\n') {
return fmt.Sprintf("<pre><code>%s</code></pre>", str)
}
return fmt.Sprintf("<code>%s</code>", str)
},
}
formatter.waReplFuncText = map[*regexp.Regexp]func(string) string{}
return formatter
}
func (formatter *Formatter) getMatrixInfoByJID(roomID id.RoomID, jid types.JID) (mxid id.UserID, displayname string) {
if puppet := formatter.bridge.GetPuppetByJID(jid); puppet != nil {
mxid = puppet.MXID
displayname = puppet.Displayname
}
if user := formatter.bridge.GetUserByJID(jid); user != nil {
mxid = user.MXID
member := formatter.bridge.StateStore.GetMember(roomID, user.MXID)
if len(member.Displayname) > 0 {
displayname = member.Displayname
}
}
return
}
func (formatter *Formatter) ParseWhatsApp(roomID id.RoomID, content *event.MessageEventContent, mentionedJIDs []string, allowInlineURL, forceHTML bool) {
output := html.EscapeString(content.Body)
for regex, replacement := range formatter.waReplString {
output = regex.ReplaceAllString(output, replacement)
}
for regex, replacer := range formatter.waReplFunc {
output = regex.ReplaceAllStringFunc(output, replacer)
}
if allowInlineURL {
output = inlineURLRegex.ReplaceAllStringFunc(output, func(s string) string {
groups := inlineURLRegex.FindStringSubmatch(s)
return fmt.Sprintf(`<a href="%s">%s</a>`, groups[2], groups[1])
})
}
alreadyMentioned := make(map[id.UserID]struct{})
content.Mentions = &event.Mentions{}
for _, rawJID := range mentionedJIDs {
jid, err := types.ParseJID(rawJID)
if err != nil {
continue
} else if jid.Server == types.LegacyUserServer {
jid.Server = types.DefaultUserServer
}
mxid, displayname := formatter.getMatrixInfoByJID(roomID, jid)
number := "@" + jid.User
output = strings.ReplaceAll(output, number, fmt.Sprintf(`<a href="https://matrix.to/#/%s">%s</a>`, mxid, displayname))
content.Body = strings.ReplaceAll(content.Body, number, displayname)
if _, ok := alreadyMentioned[mxid]; !ok {
alreadyMentioned[mxid] = struct{}{}
content.Mentions.UserIDs = append(content.Mentions.UserIDs, mxid)
}
}
if output != content.Body || forceHTML {
output = strings.ReplaceAll(output, "\n", "<br/>")
content.FormattedBody = output
content.Format = event.FormatHTML
for regex, replacer := range formatter.waReplFuncText {
content.Body = regex.ReplaceAllStringFunc(content.Body, replacer)
}
}
}
func (formatter *Formatter) ParseMatrix(html string, mentions *event.Mentions) (string, []string) {
ctx := format.NewContext()
var mentionedJIDs []string
if mentions != nil {
var allowedMentions = make(map[types.JID]bool)
mentionedJIDs = make([]string, 0, len(mentions.UserIDs))
for _, userID := range mentions.UserIDs {
var jid types.JID
if puppet := formatter.bridge.GetPuppetByMXID(userID); puppet != nil {
jid = puppet.JID
mentionedJIDs = append(mentionedJIDs, puppet.JID.String())
} else if user := formatter.bridge.GetUserByMXIDIfExists(userID); user != nil {
jid = user.JID.ToNonAD()
}
if !jid.IsEmpty() && !allowedMentions[jid] {
allowedMentions[jid] = true
mentionedJIDs = append(mentionedJIDs, jid.String())
}
}
ctx.ReturnData[allowedMentionsContextKey] = allowedMentions
}
result := formatter.matrixHTMLParser.Parse(html, ctx)
if mentions == nil {
mentionedJIDs, _ = ctx.ReturnData[mentionedJIDsContextKey].([]string)
sort.Strings(mentionedJIDs)
mentionedJIDs = slices.Compact(mentionedJIDs)
}
return result, mentionedJIDs
}
func (formatter *Formatter) ParseMatrixWithoutMentions(html string) string {
ctx := format.NewContext()
ctx.ReturnData[allowedMentionsContextKey] = map[types.JID]struct{}{}
return formatter.matrixHTMLParser.Parse(html, ctx)
}