Audacious - OLD, PLEASE USE GITHUB DISCUSSIONS/ISSUES

/*

 * Copyright (c) 2010, 2014 William Pitcock <nenolod@dereferenced.org>

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,

 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 */

#include <glib.h>

#include <glib/gstdio.h>

#include <string.h>

#include <QApplication>

#include <QContextMenuEvent>

#include <QDesktopServices>

#include <QMenu>

#include <QTextCursor>

#include <QTextDocument>

#include <QTextEdit>

#include <libxml/parser.h>

#include <libxml/tree.h>

#include <libxml/HTMLparser.h>

#include <libxml/xpath.h>

#define AUD_GLIB_INTEGRATION

#include <libaudcore/drct.h>

#include <libaudcore/i18n.h>

#include <libaudcore/plugin.h>

#include <libaudcore/plugins.h>

#include <libaudcore/audstrings.h>

#include <libaudcore/hook.h>

#include <libaudcore/vfs_async.h>

#include <libaudcore/runtime.h>

#include <libaudqt/libaudqt.h>

typedef struct {

    String filename; /* of song file */

    String title, artist;

    String uri; /* URI we are trying to retrieve */

    String local_filename; /* JWT:CALCULATED LOCAL FILENAME TO SAVE LYRICS TO */

    int startlyrics;       /* JWT:OFFSET IN LYRICS WINDOW WHERE LYRIC TEXT ACTUALLY STARTS */

    bool ok2save;          /* JWT:SET TO TRUE IF GOT LYRICS FROM LYRICWIKI (LOCAL FILE DOESN'T EXIST) */

} LyricsState;

static LyricsState state;

class TextEdit : public QTextEdit

{

public:

    TextEdit (QWidget * parent = nullptr) : QTextEdit (parent) {}

protected:

    void contextMenuEvent (QContextMenuEvent * event);

};

class LyricWikiQt : public GeneralPlugin

{

public:

    static constexpr PluginInfo info = {

        N_("LyricWiki Plugin"),

        PACKAGE,

        nullptr, // about

        nullptr, // prefs

        PluginQtOnly

    };

    constexpr LyricWikiQt () : GeneralPlugin (info, false) {}

    void * get_qt_widget ();

};

EXPORT LyricWikiQt aud_plugin_instance;

/*

 * Suppress libxml warnings, because lyricwiki does not generate anything near

 * valid HTML.

 */

static void libxml_error_handler (void * ctx, const char * msg, ...)

{

}

static CharPtr scrape_lyrics_from_lyricwiki_edit_page (const char * buf, int64_t len)

{

    xmlDocPtr doc;

    CharPtr ret;

    /*

     * temporarily set our error-handling functor to our suppression function,

     * but we have to set it back because other components of Audacious depend

     * on libxml and we don't want to step on their code paths.

     *

     * unfortunately, libxml is anti-social and provides us with no way to get

     * the previous error functor, so we just have to set it back to default after

     * parsing and hope for the best.

     */

    xmlSetGenericErrorFunc (nullptr, libxml_error_handler);

    doc = htmlReadMemory (buf, (int) len, nullptr, "utf-8", (HTML_PARSE_RECOVER | HTML_PARSE_NONET));

    xmlSetGenericErrorFunc (nullptr, nullptr);

    if (doc)

    {

        xmlXPathContextPtr xpath_ctx = nullptr;

        xmlXPathObjectPtr xpath_obj = nullptr;

        xmlNodePtr node = nullptr;

        xpath_ctx = xmlXPathNewContext (doc);

        if (! xpath_ctx)

            goto give_up;

        xpath_obj = xmlXPathEvalExpression ((xmlChar *) "//*[@id=\"wpTextbox1\"]", xpath_ctx);

        if (! xpath_obj)

            goto give_up;

        if (! xpath_obj->nodesetval->nodeMax)

            goto give_up;

        node = xpath_obj->nodesetval->nodeTab[0];

give_up:

        if (xpath_obj)

            xmlXPathFreeObject (xpath_obj);

        if (xpath_ctx)

            xmlXPathFreeContext (xpath_ctx);

        if (node)

        {

            xmlChar * lyric = xmlNodeGetContent (node);

            if (lyric)

            {

                GMatchInfo * match_info;

                GRegex * reg;

                reg = g_regex_new

                 ("<(lyrics?)>[[:space:]]*(.*?)[[:space:]]*</\\1>",

                 (GRegexCompileFlags) (G_REGEX_MULTILINE | G_REGEX_DOTALL),

                 (GRegexMatchFlags) 0, nullptr);

                g_regex_match (reg, (char *) lyric, G_REGEX_MATCH_NEWLINE_ANY, & match_info);

                ret.capture (g_match_info_fetch (match_info, 2));

                if (! strcmp_nocase (ret, "<!-- PUT LYRICS HERE (and delete this entire line) -->"))

                    ret.capture (g_strdup (_("No lyrics available")));

                g_match_info_free (match_info);

                g_regex_unref (reg);

                if (! ret)

                {

                    reg = g_regex_new

                     ("#REDIRECT \\[\\[([^:]*):(.*)]]",

                     (GRegexCompileFlags) (G_REGEX_MULTILINE | G_REGEX_DOTALL),

                     (GRegexMatchFlags) 0, nullptr);

                    if (g_regex_match (reg, (char *) lyric, G_REGEX_MATCH_NEWLINE_ANY, & match_info))

                    {

                        state.artist = String (g_match_info_fetch (match_info, 1));

                        state.title = String (g_match_info_fetch (match_info, 2));

                        state.uri = String ();

                    }

                    g_match_info_free (match_info);

                    g_regex_unref (reg);

                }

            }

            xmlFree (lyric);

        }

        xmlFreeDoc (doc);

    }

    return ret;

}

static String scrape_uri_from_lyricwiki_search_result (const char * buf, int64_t len)

{

    xmlDocPtr doc;

    String uri;

    /*

     * workaround buggy lyricwiki search output where it cuts the lyrics

     * halfway through the UTF-8 symbol resulting in invalid XML.

     */

    GRegex * reg;

    reg = g_regex_new ("<(lyrics?)>.*</\\1>", (GRegexCompileFlags)

     (G_REGEX_MULTILINE | G_REGEX_DOTALL | G_REGEX_UNGREEDY),

     (GRegexMatchFlags) 0, nullptr);

    CharPtr newbuf (g_regex_replace_literal (reg, buf, len, 0, "", G_REGEX_MATCH_NEWLINE_ANY, nullptr));

    g_regex_unref (reg);

    /*

     * temporarily set our error-handling functor to our suppression function,

     * but we have to set it back because other components of Audacious depend

     * on libxml and we don't want to step on their code paths.

     *

     * unfortunately, libxml is anti-social and provides us with no way to get

     * the previous error functor, so we just have to set it back to default after

     * parsing and hope for the best.

     */

    xmlSetGenericErrorFunc (nullptr, libxml_error_handler);

    doc = xmlParseMemory (newbuf, strlen (newbuf));

    xmlSetGenericErrorFunc (nullptr, nullptr);

    if (doc != nullptr)

    {

        xmlNodePtr root, cur;

        root = xmlDocGetRootElement(doc);

        for (cur = root->xmlChildrenNode; cur; cur = cur->next)

        {

            if (xmlStrEqual(cur->name, (xmlChar *) "url"))

            {

                auto lyric = (char *) xmlNodeGetContent (cur);

                // If the lyrics are unknown, LyricWiki returns a broken link

                // to the edit page.  Extract the song ID (artist:title) from

                // the URI and recreate a working link.

                char * title = strstr (lyric, "title=");

                if (title)

                {

                    title += 6;

                    // Strip trailing "&action=edit"

                    char * amp = strchr (title, '&');

                    if (amp)

                        * amp = 0;

                    // Spaces get replaced with plus signs for some reason.

                    str_replace_char (title, '+', ' ');

                    // LyricWiki interprets UTF-8 as ISO-8859-1, then "converts"

                    // it to UTF-8 again.  Worse, it will sometimes corrupt only

                    // the song title in this way while leaving the artist name

                    // intact.  So we have to percent-decode the URI, split the

                    // two strings apart, repair them separately, and then

                    // rebuild the URI.

                    auto strings = str_list_to_index (str_decode_percent (title), ":");

                    for (String & s : strings)

                    {

                        StringBuf orig_utf8 = str_convert (s, -1, "UTF-8", "ISO-8859-1");

                        if (orig_utf8 && g_utf8_validate (orig_utf8, -1, nullptr))

                            s = String (orig_utf8);

                    }

                    uri = String (str_printf ("https://lyrics.fandom.com/index.php?"

                     "action=edit&title=%s", (const char *) str_encode_percent

                     (index_to_str_list (strings, ":"))));

                }

                else

                {

                    // Convert normal lyrics link to edit page link

                    char * slash = strrchr (lyric, '/');

                    // if (slash && ! strstr (slash, "lyrics.wikia.com")) // JWT:FIXME?! - CHGD. TO MATCH GTK SIDE!:

                    if (slash))

                        uri = String (str_printf ("https://lyrics.fandom.com/index.php?"

                         "action=edit&title=%s", slash + 1));

                    else

                        uri = String ("N/A");

                }

                xmlFree ((xmlChar *) lyric);

            }

        }

        xmlFreeDoc (doc);

    }

    return uri;

}

static void update_lyrics_window (const char * title, const char * artist, const char * lyrics);

static void get_lyrics_step_1 ();

static void get_lyrics_step_3 (const char * uri, const Index<char> & buf, void *)

{

    if (! state.uri || strcmp (state.uri, uri))

        return;

    if (! buf.len ())

    {

        update_lyrics_window (_("Error"), nullptr,

         str_printf (_("Unable to fetch %s"), uri));

        return;

    }

    CharPtr lyrics = scrape_lyrics_from_lyricwiki_edit_page (buf.begin (), buf.len ());

    if (! state.uri)

    {

        get_lyrics_step_1 ();

        return;

    }

    if (! lyrics)

    {

        update_lyrics_window (_("No lyrics Found"),

                (const char *) str_concat ({"Title: ", (const char *) state.title, "\nArtist: ",

                        (const char *) state.artist}),

                str_printf (_("Unable to parse %s"), uri));

        return;

    }

    update_lyrics_window (state.title, state.artist, lyrics);

    state.ok2save = true;

}

static void get_lyrics_step_2 (const char * uri1, const Index<char> & buf, void *)

{

    if (! state.uri || strcmp (state.uri, uri1))

        return;

    if (! buf.len ())

    {

        update_lyrics_window (_("Error"), nullptr,

         str_printf (_("Unable to fetch %s"), uri1));

        return;

    }

    String uri = scrape_uri_from_lyricwiki_search_result (buf.begin (), buf.len ());

    if (! uri)

    {

        update_lyrics_window (_("Error"), nullptr,

         str_printf (_("Unable to parse %s"), uri1));

        return;

    }

    else if (uri == String ("N/A"))

    {

        update_lyrics_window (state.title, state.artist,

         _("No lyrics available"));

        return;

    }

    state.uri = uri;

    update_lyrics_window (state.title, state.artist, _("Looking for lyrics ..."));

    vfs_async_file_get_contents (uri, get_lyrics_step_3, nullptr);

}

static void get_lyrics_step_1 ()

{

    if (! state.artist || ! state.title)

    {

        update_lyrics_window (_("Error"), nullptr, _("Missing title and/or artist"));

        return;

    }

    StringBuf title_buf = str_encode_percent (state.title);

    StringBuf artist_buf = str_encode_percent (state.artist);

    state.uri = String (str_printf ("https://lyrics.fandom.com/api.php?"

     "action=lyrics&artist=%s&song=%s&fmt=xml", (const char *) artist_buf,

     (const char *) title_buf));

    update_lyrics_window (state.title, state.artist, _("Connecting to lyrics.fandom.com ..."));

    vfs_async_file_get_contents (state.uri, get_lyrics_step_2, nullptr);

}

static void get_lyrics_step_0 (const char * uri, const Index<char> & buf, void *)

{

    if (! buf.len ())

    {

        update_lyrics_window (_("Error"), nullptr,

         str_printf (_("Unable to fetch file %s"), uri));

        return;

    }

    StringBuf nullterminated_buf = str_copy (buf.begin (), buf.len ());

    update_lyrics_window (state.title, state.artist, (const char *) nullterminated_buf);

    /* JWT:ALLOW 'EM TO EDIT LYRICWIKI, EVEN IF LYRICS ARE LOCAL, IF THEY HAVE BOTH REQUIRED FIELDS: */

    if (state.artist && state.title)

    {

        StringBuf title_buf = str_copy (state.title);

        str_replace_char (title_buf, ' ', '_');

        title_buf = str_encode_percent (title_buf, -1);

        StringBuf artist_buf = str_copy (state.artist);

        str_replace_char (artist_buf, ' ', '_');

        artist_buf = str_encode_percent (artist_buf, -1);

        state.uri = String (str_printf ("https://lyrics.fandom.com/index.php?action=edit&title=%s:%s",

                (const char *) artist_buf, (const char *) title_buf));

    }

}

static QTextEdit * textedit;

static void save_lyrics_locally ()

{

    if (state.local_filename)

    {

        QString lyrics = textedit->toPlainText ();

        if (! lyrics.isNull() && ! lyrics.isEmpty())

        {

            if (state.startlyrics > 0)

                lyrics.remove(0, state.startlyrics);

            int sz = lyrics.length ();

            if (sz > 0)

            {

                if (strstr ((const char *) state.local_filename, "/lyrics/"))

                {

                    GStatBuf statbuf;

                    StringBuf path = filename_get_parent ((const char *) state.local_filename);

                    if (g_stat ((const char *) path, & statbuf)

                            && g_mkdir ((const char *) path, 0755))

                    {

                        AUDERR ("e:Could not create missing lyrics directory (%s)!\n", (const char *) path);

                        return;

                    }

                }

                VFSFile file (state.local_filename, "w");

                if (file)

                {

                    if (file.fwrite (lyrics.toUtf8().constData(), 1, sz) == sz)

                        AUDINFO ("i:Successfully saved %d bytes of lyrics locally to (%s).\n", sz,

                                (const char *) state.local_filename);

                    state.ok2save = false;

                }

            }

        }

    }

}

static void update_lyrics_window (const char * title, const char * artist, const char * lyrics)

{

    if (! textedit)

        return;

    textedit->document ()->clear ();

    QTextCursor cursor (textedit->document ());

    cursor.insertHtml (QString ("<big><b>") + QString (title) + QString ("</b></big>"));

    if (artist)

    {

        cursor.insertHtml (QString ("<br><i>") + QString (artist) + QString ("</i>"));

    }

    cursor.insertHtml ("<br><br>");

    QString prelyrics = textedit->toPlainText ();

    state.startlyrics = prelyrics.length ();

    cursor.insertText (lyrics);

}

static void lyricwiki_playback_began ()

{

    /* FIXME: cancel previous VFS requests (not possible with current API) */

    bool found_lyricfile = false;

    GStatBuf statbuf;

    String lyricStr = String ("");

    StringBuf path = StringBuf ();

    state.filename = aud_drct_get_filename ();

    state.uri = String ();

    state.local_filename = String ("");

    if (! strncmp ((const char *) state.filename, "file://", 7))  // JWT:WE'RE A LOCAL FILE, CHECK FOR CORRESPONDING LYRICS FILE:

    {

        /* JWT: EXTRACT JUST THE "NAME" PART TO USE TO NAME THE LYRICS FILE: */

        const char * slash = state.filename ? strrchr (state.filename, '/') : nullptr;

        const char * base = slash ? slash + 1 : nullptr;

        if (base && base[0])

        {

            /* JWT:FIRST CHECK LOCAL DIRECTORY FOR A LYRICS FILE MATCHING FILE-NAME: */

            const char * dot = strrchr (base, '.');

            int ln = (dot && ! strstr (dot, ".cue?")) ? (dot - base) : -1;  // SET TO FULL LENGTH(-1) IF NO EXTENSION OR NOT A CUESHEET.

            path = filename_get_parent (uri_to_filename (state.filename));

            lyricStr = String (str_concat ({path, "/", str_decode_percent (base, ln), ".lrc"}));

            found_lyricfile = ! (g_stat ((const char *) lyricStr, & statbuf));

            state.local_filename = lyricStr;

            if (! found_lyricfile)

            {

                /* JWT:LOCAL LYRIC FILE NOT FOUND, SO CHECK THE GLOBAL CONFIG PATH FOR A MATCHING LYRICS FILE: */

                lyricStr = String (str_concat ({aud_get_path (AudPath::UserDir), "/lyrics/",

                        str_decode_percent (base, ln), ".lrc"}));

                found_lyricfile = ! (g_stat ((const char *) lyricStr, & statbuf));

            }

        }

    }

    Tuple tuple = aud_drct_get_tuple ();

    state.title = tuple.get_str (Tuple::Title);

    state.artist = tuple.get_str (Tuple::Artist);

    state.ok2save = false;

    if (found_lyricfile)  // JWT:WE HAVE LYRICS STORED IN A LOCAL FILE MATCHING FILE NAME!:

    {

        AUDINFO ("i:Local lyric file found (%s).\n", (const char *) lyricStr);

        vfs_async_file_get_contents (lyricStr, get_lyrics_step_0, nullptr);

    }

    else  // NO LOCAL LYRICS FILE FOUND, SO CHECK FOR LYRIC FILE MATCHING TITLE:

    {

        if (state.title)

        {

            /* JWT:MANY STREAMS & SOME FILES FORMAT THE TITLE FIELD AS:

               "[Artist: ]<artist> - [Title: ]<title> [<other-stuff>?]".  IF SO, THEN PARSE OUT THE

               ARTIST AND TITLE COMPONENTS FROM THE TITLE FOR SEARCHING LYRICWIKI:

            */

            const char * ttlstart = (const char *) state.title;

            int ttllen = strlen (ttlstart);  // MAKE SURE WE DON'T OVERRUN (THIS IS C)! ;^)

            if (ttllen > 8 && ! strcmp_nocase (ttlstart, "Artist:", 7))

                ttlstart += 8;

            if (ttllen > 0)  // MAKE SURE WE DON'T OVERRUN!

            {

                const char * ttloffset = ttlstart ? strstr (ttlstart, " - ") : nullptr;

                if (ttloffset)

                {

                    state.artist = String (str_copy (ttlstart, (ttloffset-ttlstart)));

                    ttloffset += 3;

                    ttllen -= 3;

                    if (ttllen > 7 && ! strcmp_nocase (ttloffset, "Title:", 6))

                        ttloffset += 7;

                    ttllen = strlen (ttloffset);

                    if (ttllen > 0)

                    {

                        const char * ttlend = strstr (ttloffset, " - ");

                        if (ttlend)

                            state.title = String (str_copy (ttloffset, ttlend-ttloffset));

                        else

                        {

                            auto split = str_list_to_index (ttloffset, "|/");

                            for (auto & str : split)

                            {

                                int ttllen_1 = strlen (str) - 1;  // "CHOMP" ANY TRAILING SPACES:

                                while (ttllen_1 >= 0 && str[ttllen_1] == ' ')

                                    ttllen_1--;

                                if (ttllen_1 >= 0)

                                {

                                    StringBuf titleBuf = str_copy (str);

                                    titleBuf.resize (ttllen_1+1);

                                    state.title = String (titleBuf);

                                }

                                break;

                            }

                        }

                    }

                }

                if (! state.local_filename || ! state.local_filename[0])

                {

                    /* JWT:NO LOCAL LYRIC FILE, SO TRY SEARCH FOR LYRIC FILE BY TITLE: */

                    StringBuf titleBuf = str_copy (state.title);

                    /* DON'T %-ENCODE SPACES BY CONVERTING TO A "LEGAL" CHAR. NOT (LIKELY) IN FILE-NAMES/TITLES: */

                    str_replace_char (titleBuf, ' ', '~');

                    titleBuf = str_encode_percent ((const char *) titleBuf, -1);

                    str_replace_char (titleBuf, '~', ' ');  // (THEN CONVERT 'EM BACK TO SPACES)

                    if (path)

                    {

                        /* ENTRY IS A LOCAL FILE, SO FIRST CHECK DIRECTORY THE FILE IS IN: */

                        lyricStr = String (str_concat ({path, "/", titleBuf, ".lrc"}));

                        found_lyricfile = ! (g_stat ((const char *) lyricStr, & statbuf));

                        state.local_filename = lyricStr;

                        if (found_lyricfile)

                        {

                            AUDINFO ("i:Local lyric file found by title (%s).\n", (const char *) lyricStr);

                            vfs_async_file_get_contents (lyricStr, get_lyrics_step_0, nullptr);

                            return;

                        }

                    }

                    /* OTHERWISE (STREAM, ETC.), CHECK THE GLOBAL CONFIG PATH FOR LYRICS FILE MATCHING TITLE: */

                    lyricStr = String (str_concat ({aud_get_path (AudPath::UserDir),

                            "/lyrics/", titleBuf, ".lrc"}));

                    found_lyricfile = ! (g_stat ((const char *) lyricStr, & statbuf));

                    state.local_filename = lyricStr;

                    if (found_lyricfile)

                    {

                        AUDINFO ("i:Global lyric file found by title (%s).\n", (const char *) lyricStr);

                        vfs_async_file_get_contents (lyricStr, get_lyrics_step_0, nullptr);

                        return;

                    }

                }

            }

        }

        /* IF HERE, NO LOCAL LYRICS FILE BY FILENAME OR TITLE, SEARCH LYRICWIKI: */

        AUDINFO ("i:No Local lyric file found, try fetching from lyricwiki...\n");

        get_lyrics_step_1 ();

    }

    lyricStr = String ();

}

static void lw_cleanup (QObject * object = nullptr)

{

    state.filename = String ();

    state.title = String ();

    state.artist = String ();

    state.uri = String ();

    state.local_filename = String ();

    hook_dissociate ("tuple change", (HookFunction) lyricwiki_playback_began);

    hook_dissociate ("playback ready", (HookFunction) lyricwiki_playback_began);

    textedit = nullptr;

}

void * LyricWikiQt::get_qt_widget ()

{

    textedit = new TextEdit;

    textedit->setReadOnly (true);

#ifdef Q_OS_MAC  // Mac-specific font tweaks

    textedit->document ()->setDefaultFont (QApplication::font ("QTipLabel"));

#endif

    hook_associate ("tuple change", (HookFunction) lyricwiki_playback_began, nullptr);

    hook_associate ("playback ready", (HookFunction) lyricwiki_playback_began, nullptr);

    if (aud_drct_get_ready ())

        lyricwiki_playback_began ();

    QObject::connect (textedit, & QObject::destroyed, lw_cleanup);

    return textedit;

}

void TextEdit::contextMenuEvent (QContextMenuEvent * event)

{

    QMenu * menu = createStandardContextMenu ();

    menu->addSeparator ();

    if (state.uri)

    {

        QAction * edit = menu->addAction (_("Edit Lyricwiki"));

        QObject::connect (edit, & QAction::triggered, [] () {

            QDesktopServices::openUrl (QUrl ((const char *) state.uri));

        });

    }

    if (state.ok2save)

    {

        QAction * save_button = menu->addAction (_("Save Locally"));

        QObject::connect (save_button, & QAction::triggered, [] () {

            save_lyrics_locally ();

        });

    }

    menu->exec (event->globalPos ());

    delete menu;

}