Linkify plain text mails

4 files changed, 314 insertions, 1 deletions

diff --git a/framework/src/CMakeLists.txt b/framework/src/CMakeLists.txt
index 10773f8a..54dcd4dc 100644
--- a/framework/src/CMakeLists.txt
+++ b/framework/src/CMakeLists.txt
@@ -36,6 +36,7 @@ set(SRCS
     domain/contactcontroller.cpp
     domain/controller.cpp
     domain/peoplemodel.cpp
+    domain/htmlutils.cpp
     accounts/accountfactory.cpp
     accounts/accountsmodel.cpp
     fabric.cpp
diff --git a/framework/src/domain/htmlutils.cpp b/framework/src/domain/htmlutils.cpp
new file mode 100644
index 00000000..156bcc48
--- /dev/null
+++ b/framework/src/domain/htmlutils.cpp
@@ -0,0 +1,286 @@
+/*
+    Copyright (c) 2017 Christian Mollekopf <mollekopf@kolabsys.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library 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 Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+#include "htmlutils.h"
+
+#include <QTextDocument>
+
+static QString resolveEntities(const QString &in)
+{
+        QString out;
+
+        for(int i = 0; i < (int)in.length(); ++i) {
+                if(in[i] == '&') {
+                        // find a semicolon
+                        ++i;
+                        int n = in.indexOf(';', i);
+                        if(n == -1)
+                                break;
+                        QString type = in.mid(i, (n-i));
+                        i = n; // should be n+1, but we'll let the loop increment do it
+
+                        if(type == "amp")
+                                out += '&';
+                        else if(type == "lt")
+                                out += '<';
+                        else if(type == "gt")
+                                out += '>';
+                        else if(type == "quot")
+                                out += '\"';
+                        else if(type == "apos")
+                                out += '\'';
+                        else if(type == "nbsp")
+                                out += 0xa0;
+                } else {
+                        out += in[i];
+                }
+        }
+
+        return out;
+}
+
+
+static bool linkify_pmatch(const QString &str1, int at, const QString &str2)
+{
+        if(str2.length() > (str1.length()-at))
+                return false;
+
+        for(int n = 0; n < (int)str2.length(); ++n) {
+                if(str1.at(n+at).toLower() != str2.at(n).toLower())
+                        return false;
+        }
+
+        return true;
+}
+
+static bool linkify_isOneOf(const QChar &c, const QString &charlist)
+{
+        for(int i = 0; i < (int)charlist.length(); ++i) {
+                if(c == charlist.at(i))
+                        return true;
+        }
+
+        return false;
+}
+
+// encodes a few dangerous html characters
+static QString linkify_htmlsafe(const QString &in)
+{
+        QString out;
+
+        for(int n = 0; n < in.length(); ++n) {
+                if(linkify_isOneOf(in.at(n), "\"\'`<>")) {
+                        // hex encode
+                        QString hex;
+                        hex.sprintf("%%%02X", in.at(n).toLatin1());
+                        out.append(hex);
+                } else {
+                        out.append(in.at(n));
+                }
+        }
+
+        return out;
+}
+
+static bool linkify_okUrl(const QString &url)
+{
+        if(url.at(url.length()-1) == '.')
+                return false;
+
+        return true;
+}
+
+static bool linkify_okEmail(const QString &addy)
+{
+        // this makes sure that there is an '@' and a '.' after it, and that there is
+        // at least one char for each of the three sections
+        int n = addy.indexOf('@');
+        if(n == -1 || n == 0)
+                return false;
+        int d = addy.indexOf('.', n+1);
+        if(d == -1 || d == 0)
+                return false;
+        if((addy.length()-1) - d <= 0)
+                return false;
+        if(addy.indexOf("..") != -1)
+                return false;
+
+        return true;
+}
+
+/**
+ * takes a richtext string and heuristically adds links for uris of common protocols
+ * @return a richtext string with link markup added
+ */
+QString HtmlUtils::linkify(const QString &in)
+{
+        QString out = in;
+        int x1, x2;
+        bool isUrl, isAtStyle;
+        QString linked, link, href;
+
+        for(int n = 0; n < (int)out.length(); ++n) {
+                isUrl = false;
+                isAtStyle = false;
+                x1 = n;
+
+                if(linkify_pmatch(out, n, "xmpp:")) {
+                        n += 5;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "mailto:")) {
+                        n += 7;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "http://")) {
+                        n += 7;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "https://")) {
+                        n += 8;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "ftp://")) {
+                        n += 6;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "news://")) {
+                        n += 7;
+                        isUrl = true;
+                        href = "";
+                }
+                else if (linkify_pmatch(out, n, "ed2k://")) {
+                        n += 7;
+                        isUrl = true;
+                        href = "";
+                }
+                else if (linkify_pmatch(out, n, "magnet:")) {
+                        n += 7;
+                        isUrl = true;
+                        href = "";
+                }
+                else if(linkify_pmatch(out, n, "www.")) {
+                        isUrl = true;
+                        href = "http://";
+                }
+                else if(linkify_pmatch(out, n, "ftp.")) {
+                        isUrl = true;
+                        href = "ftp://";
+                }
+                else if(linkify_pmatch(out, n, "@")) {
+                        isAtStyle = true;
+                        href = "x-psi-atstyle:";
+                }
+
+                if(isUrl) {
+                        // make sure the previous char is not alphanumeric
+                        if(x1 > 0 && out.at(x1-1).isLetterOrNumber())
+                                continue;
+
+                        // find whitespace (or end)
+                        QMap<QChar, int> brackets;
+                        brackets['('] = brackets[')'] = brackets['['] = brackets[']'] = brackets['{'] = brackets['}'] = 0;
+                        QMap<QChar, QChar> openingBracket;
+                        openingBracket[')'] = '(';
+                        openingBracket[']'] = '[';
+                        openingBracket['}'] = '{';
+                        for(x2 = n; x2 < (int)out.length(); ++x2) {
+                                if(out.at(x2).isSpace() || linkify_isOneOf(out.at(x2), "\"\'`<>")
+                                        || linkify_pmatch(out, x2, "&quot;")  || linkify_pmatch(out, x2, "&apos;")
+                                        || linkify_pmatch(out, x2, "&gt;") || linkify_pmatch(out, x2, "&lt;") ) {
+                                        break;
+                                }
+                                if(brackets.keys().contains(out.at(x2))) {
+                                        ++brackets[out.at(x2)];
+                                }
+                        }
+                        int len = x2-x1;
+                        QString pre = resolveEntities(out.mid(x1, x2-x1));
+
+                        // go backward hacking off unwanted punctuation
+                        int cutoff;
+                        for(cutoff = pre.length()-1; cutoff >= 0; --cutoff) {
+                                if(!linkify_isOneOf(pre.at(cutoff), "!?,.()[]{}<>\""))
+                                        break;
+                                if(linkify_isOneOf(pre.at(cutoff), ")]}")
+                                        && brackets[pre.at(cutoff)] - brackets[openingBracket[pre.at(cutoff)]] <= 0 ) {
+                                        break;  // in theory, there could be == above, but these are urls, not math ;)
+                                }
+                                if(brackets.keys().contains(pre.at(cutoff))) {
+                                        --brackets[pre.at(cutoff)];
+                                }
+
+                        }
+                        ++cutoff;
+                        //++x2;
+
+                        link = pre.mid(0, cutoff);
+                        if(!linkify_okUrl(link)) {
+                                n = x1 + link.length();
+                                continue;
+                        }
+                        href += link;
+                        // attributes need to be encoded too.
+                        href = href.toHtmlEscaped();
+                        href = linkify_htmlsafe(href);
+                        //printf("link: [%s], href=[%s]\n", link.latin1(), href.latin1());
+                        linked = QString("<a href=\"%1\">").arg(href) + link.toHtmlEscaped() + "</a>" + pre.mid(cutoff).toHtmlEscaped();
+                        out.replace(x1, len, linked);
+                        n = x1 + linked.length() - 1;
+                } else if(isAtStyle) {
+                        // go backward till we find the beginning
+                        if(x1 == 0)
+                                continue;
+                        --x1;
+                        for(; x1 >= 0; --x1) {
+                                if(!linkify_isOneOf(out.at(x1), "_.-+") && !out.at(x1).isLetterOrNumber())
+                                        break;
+                        }
+                        ++x1;
+
+                        // go forward till we find the end
+                        x2 = n + 1;
+                        for(; x2 < (int)out.length(); ++x2) {
+                                if(!linkify_isOneOf(out.at(x2), "_.-+") && !out.at(x2).isLetterOrNumber())
+                                        break;
+                        }
+
+                        int len = x2-x1;
+                        link = out.mid(x1, len);
+                        //link = resolveEntities(link);
+
+                        if(!linkify_okEmail(link)) {
+                                n = x1 + link.length();
+                                continue;
+                        }
+
+                        href += link;
+                        //printf("link: [%s], href=[%s]\n", link.latin1(), href.latin1());
+                        linked = QString("<a href=\"%1\">").arg(href) + link + "</a>";
+                        out.replace(x1, len, linked);
+                        n = x1 + linked.length() - 1;
+                }
+        }
+
+        return out;
+}
diff --git a/framework/src/domain/htmlutils.h b/framework/src/domain/htmlutils.h
new file mode 100644
index 00000000..b59da1dc
--- /dev/null
+++ b/framework/src/domain/htmlutils.h
@@ -0,0 +1,25 @@
+/*
+    Copyright (c) 2017 Christian Mollekopf <mollekopf@kolabsys.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library 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 Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+#pragma once
+
+#include <QString>
+
+namespace HtmlUtils {
+    QString linkify(const QString &in);
+}
diff --git a/framework/src/domain/messageparser_new.cpp b/framework/src/domain/messageparser_new.cpp
index c353becf..7e7dbfa6 100644
--- a/framework/src/domain/messageparser_new.cpp
+++ b/framework/src/domain/messageparser_new.cpp
@@ -19,6 +19,7 @@
 
 #include "messageparser.h"
 #include "mimetreeparser/interface.h"
+#include "htmlutils.h"
 
 #include <QDebug>
 #include <QTextDocument>
@@ -470,7 +471,7 @@ QVariant NewModel::data(const QModelIndex &index, int role) const
                     }
                 } else { //We assume plain
                     //We alwas do richtext (so we get highlighted links and stuff).
-                    return Qt::convertFromPlainText(text);
+                    return HtmlUtils::linkify(Qt::convertFromPlainText(text));
                 }
                 return text;
             }