/*
 * * Copyright (C) 2009-2011 Ali <aliov@xfce.org>
 * * Copyright (C) 2012-2017 Sean Davis <smd.seandavis@gmail.com>
 * * Copyright (C) 2012-2017 Simon Steinbeiß <ochosi@xfce.org>
 *
 * Licensed under the GNU General Public License Version 2
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

/*
 * Based on code from:
 *
 * Totem pl parser: Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007 Bastien Nocera
 *              Copyright (C) 2003, 2004 Colin Walters <walters@rhythmbox.org>
 *
 * xfmedia:     Copyright (c) 2004-2005 Brian Tarricone, <bjt23@cornell.edu>
 *
 * Thanks :).
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <gio/gio.h>
#include <glib.h>

#include <libxfce4util/libxfce4util.h>

#include "src/misc/parole-debug.h"
#include "src/misc/parole-enum-types.h"
#include "src/misc/parole-file.h"
#include "src/misc/parole-filters.h"

#include "src/misc/parole-pl-parser.h"

typedef struct {
    GSList    *list;
    gboolean  started;
    gchar    *uri;
    gchar    *title;
} ParoleParserData;

gchar *g_substr(const gchar* str, gint start, gint end);

static gchar*
parole_filename_to_utf8(const gchar* filename) {
    gsize read_size, written;

    gchar *utf8;
    gchar *tmp = g_strdup(filename);
    tmp = g_strconcat(tmp, "\0", NULL);

    utf8 = g_filename_to_utf8(tmp, -1, &read_size, &written, NULL);
    g_free(tmp);
    return utf8;
}

static void
parole_xspf_xml_start(GMarkupParseContext *context, const gchar *element_name,
                       const gchar **attribute_names, const gchar **attribute_values,
                       gpointer user_data, GError **error) {
    ParoleParserData *data = user_data;

    if ( !data->started ) {
        if (!g_ascii_strcasecmp (element_name, "playlist") )
            data->started = TRUE;
    }
}

static void
parole_xspf_xml_text(GMarkupParseContext *context,
                     const gchar *text, gsize text_len,
                     gpointer user_data, GError **error) {
    ParoleParserData *data = user_data;
    const gchar *element_name;

    if (!data->started)
        return;

    element_name = g_markup_parse_context_get_element(context);

    if (!g_ascii_strcasecmp(element_name, "location")) {
        if (data->uri) {
            g_free(data->uri);
            data->uri = NULL;
        }

        if (text_len > 0)
            data->uri = g_strdup(text);
    } else if (!g_ascii_strcasecmp(element_name, "title")) {
        if (data->title) {
            g_free(data->title);
            data->title = NULL;
        }

        if (text_len > 0)
            data->title = g_strdup(text);
    }
}

static void
parole_xspf_xml_end(GMarkupParseContext *context, const gchar *element_name, gpointer user_data, GError **error) {
    ParoleParserData *data = user_data;
    ParoleFile *file;

    if (!g_ascii_strcasecmp (element_name, "playlist"))
        data->started = FALSE;

    if (!data->started)
        return;

    if (!g_ascii_strcasecmp(element_name, "track")) {
        if (data->uri) {
            file = parole_file_new_with_display_name(data->uri, data->title);
            data->list = g_slist_append(data->list, file);

            g_free(data->uri);
            data->uri = NULL;
        }

        if (data->title) {
            g_free(data->title);
            data->title = NULL;
        }
    }
}

static void
parole_asx_xml_start(GMarkupParseContext *context, const gchar *element_name,
                      const gchar **attribute_names, const gchar **attribute_values,
                      gpointer user_data, GError **error) {
    guint i;
    ParoleParserData *data = user_data;

    if ( !data->started ) {
        if (!g_ascii_strcasecmp (element_name, "asx") )
            data->started = TRUE;
        else
            return;
    }

    if (!g_ascii_strcasecmp(element_name, "ref")) {
        if (data->uri) {
            g_free(data->uri);
            data->uri = NULL;
        }

        for (i = 0; attribute_names[i]; i++) {
            if (!g_ascii_strcasecmp(attribute_names[i], "href")) {
                data->uri = g_strdup(attribute_values[i]);
                break;
            }
        }
    }
}

static void
parole_asx_xml_text(GMarkupParseContext *context,
                    const gchar *text, gsize text_len,
                    gpointer user_data, GError **error) {
    ParoleParserData *data = user_data;
    const gchar *element_name;

    if (!data->started)
        return;

    element_name = g_markup_parse_context_get_element(context);

    if (!g_ascii_strcasecmp(element_name, "title")) {
        if (data->title) {
            g_free(data->title);
            data->title = NULL;
        }

        if (text_len > 0)
            data->title = g_strdup(text);
    }
}

static void
parole_asx_xml_end(GMarkupParseContext *context, const gchar *element_name, gpointer user_data, GError **error) {
    ParoleParserData *data = user_data;
    ParoleFile *file;

    if (!g_ascii_strcasecmp(element_name, "ASX"))
        data->started = FALSE;

    if (!data->started)
        return;

    if (!g_ascii_strcasecmp(element_name, "entry")) {
        if (data->uri) {
            file = parole_file_new_with_display_name(data->uri, data->title);
            data->list = g_slist_append(data->list, file);

            g_free(data->uri);
            data->uri = NULL;
        }

        if (data->title) {
            g_free(data->title);
            data->title = NULL;
        }
    }
}

static GSList *
parole_pl_parser_parse_asx(const gchar *filename) {
    ParoleParserData data;
    GFile *file;
    gchar *contents;
    GError *error = NULL;
    gsize size;
    GMarkupParseContext *pctx;
    GMarkupParser parser = {
        parole_asx_xml_start,
        parole_asx_xml_end,
        parole_asx_xml_text,
        NULL,
        NULL
    };

    data.list = NULL;
    data.title = data.uri = NULL;

    file = g_file_new_for_path(filename);

    if (!g_file_load_contents (file, NULL, &contents, &size, NULL, NULL))
        goto out;

    if (g_utf8_validate(contents, -1, NULL) == FALSE) {
        gchar *fixed;
        fixed = g_convert(contents, -1, "UTF-8", "ISO8859-1", NULL, NULL, NULL);
        if (fixed != NULL) {
            g_free(contents);
            contents = fixed;
        }
    }

    pctx = g_markup_parse_context_new(&parser, 0, &data, NULL);

    if ( !g_markup_parse_context_parse(pctx, contents, size, &error) ) {
        if ( error ) {
            g_critical("Unable to parse asx file : %s : %s\n", filename, error->message);
            g_error_free(error);
        }
    } else {
        if ( !g_markup_parse_context_end_parse(pctx, &error) ) {
            g_critical("Unable to finish parsing ASX playlist file %s", error->message);
            g_error_free(error);
        }
    }

    g_markup_parse_context_free(pctx);

out:
    g_object_unref(file);
    return data.list;
}

gchar *
g_substr(const gchar* str, gint start, gint end) {
    gsize len = (end - start + 1);
    gchar *output = g_malloc0(len + 1);
    return g_utf8_strncpy (output, &str[start], len);
}

static GSList *
parole_pl_parser_parse_m3u(const gchar *filename) {
    GFile *file;
    gchar **lines;
    gchar *contents;
    gchar *path, *pl_filename = NULL;
    GSList *list = NULL;
    gsize size;
    guint num_lines;
    const gchar *split_char;
    guint i;

    GRegex *regex;
    GMatchInfo *match_info = NULL;

    file = g_file_new_for_path(filename);
    path = g_path_get_dirname(filename);

    if (!g_file_load_contents (file, NULL, &contents, &size, NULL, NULL))
        goto out;

    if (g_utf8_validate(contents, -1, NULL) == FALSE) {
        gchar *fixed;
        fixed = g_convert(contents, -1, "UTF-8", "ISO8859-1", NULL, NULL, NULL);
        if (fixed != NULL) {
            g_free(contents);
            contents = fixed;
        }
    }

    if (strstr(contents, "\x0d") == NULL) {
        split_char = "\n";
    } else {
        split_char = "\x0d\n";
    }

    lines = g_strsplit(contents, split_char, 0);
    g_free(contents);

    // Regular expression for stream protocols, such as http:// and smb://
    regex = g_regex_new("^(?!/)[a-zA-Z_0-9]+://", 0, 0, NULL);

    num_lines = g_strv_length(lines);
    num_lines--; /* Drop the terminating NULL */

    for (i = 0; lines[i] != NULL; i++) {
        if ( lines[i][0] == '\0' || lines[i][0] == '#')
            continue;

        /* Absolute, local path */
        if ( lines[i][0] == '/' ) {
            pl_filename = g_strdup(lines[i]);
        } else {
            /* Stream protocol */
            if ( g_regex_match(regex, lines[i], 0, &match_info) ) {
                pl_filename = g_strdup(lines[i]);
            } else {
                /* Relative path */
                pl_filename = g_strjoin("/", path, lines[i], NULL);
            }
        }

        list = g_slist_append(list, parole_file_new(pl_filename));
    }

    if (pl_filename)
        g_free(pl_filename);
    g_strfreev(lines);

    g_match_info_free(match_info);
    g_regex_unref(regex);
out:

    g_object_unref(file);
    return list;
}

static GSList *
parole_pl_parser_parse_pls(const gchar *filename) {
    XfceRc *rcfile;
    GSList *list = NULL;
    ParoleFile *file;
    const gchar *file_entry, *title_entry;
    guint i, nentries;
    gchar key[128];

    rcfile = xfce_rc_simple_open(filename, TRUE);

    if (xfce_rc_has_group(rcfile, "playlist")) {
        xfce_rc_set_group(rcfile, "playlist");

        nentries = xfce_rc_read_int_entry(rcfile, "NumberOfEntries", 0);

        for (i = 1; i <= nentries; i++) {
            g_snprintf(key, 128, "File%d", i);

            file_entry = xfce_rc_read_entry(rcfile, key, NULL);

            if (!file_entry)
                continue;

            g_snprintf(key, 128, "Title%d", i);

            title_entry = xfce_rc_read_entry(rcfile, key, NULL);

            file = parole_file_new_with_display_name(file_entry, title_entry);
            list = g_slist_append(list, file);
        }
    }

    xfce_rc_close(rcfile);

    return list;
}

static GSList *
parole_pl_parser_parse_xspf(const gchar *filename) {
    ParoleParserData data;
    GFile *file;
    gchar *contents;
    GError *error = NULL;
    gsize size;
    GMarkupParseContext *pctx;
    GMarkupParser parser = {
        parole_xspf_xml_start,
        parole_xspf_xml_end,
        parole_xspf_xml_text,
        NULL,
        NULL
    };

    data.list = NULL;
    data.title = data.uri = NULL;

    file = g_file_new_for_path(filename);

    if ( !g_file_load_contents (file, NULL, &contents, &size, NULL, NULL) )
        goto out;

    if (g_utf8_validate(contents, -1, NULL) == FALSE) {
        gchar *fixed;
        fixed = g_convert(contents, -1, "UTF-8", "ISO8859-1", NULL, NULL, NULL);
        if (fixed != NULL) {
            g_free(contents);
            contents = fixed;
        }
    }

    pctx = g_markup_parse_context_new(&parser, 0, &data, NULL);

    if ( !g_markup_parse_context_parse(pctx, contents, size, &error) ) {
        if ( error ) {
            g_critical("Unable to parse xspf file : %s : %s\n", filename, error->message);
            g_error_free(error);
        }
    } else {
        if ( !g_markup_parse_context_end_parse(pctx, &error) ) {
            g_critical("Unable to finish parsing xspf playlist file %s", error->message);
            g_error_free(error);
        }
    }

    g_markup_parse_context_free(pctx);

out:
    g_object_unref(file);
    return data.list;
}

static GSList *
parole_pl_parser_parse(ParolePlFormat format, const gchar *filename) {
    GSList *list = NULL;

    switch (format) {
        case PAROLE_PL_FORMAT_M3U:
            list = parole_pl_parser_parse_m3u(filename);
            break;
        case PAROLE_PL_FORMAT_PLS:
            list = parole_pl_parser_parse_pls(filename);
            break;
        case PAROLE_PL_FORMAT_ASX:
            list = parole_pl_parser_parse_asx(filename);
            break;
        case PAROLE_PL_FORMAT_XSPF:
            list = parole_pl_parser_parse_xspf(filename);
            break;
        default:
            break;
    }

    return list;
}

static gboolean
parole_pl_parser_save_m3u(FILE *f, GSList *files) {
    guint len;
    guint i;

    gchar *display_name = NULL;
    gchar *file_name = NULL;

    fputs("#EXTM3U\n\n", f);

    len = g_slist_length(files);

    for (i = 0; i < len; i++) {
        ParoleFile *file;
        file = g_slist_nth_data(files, i);
        display_name = g_strdup(parole_file_get_display_name(file));
        file_name = parole_filename_to_utf8(parole_file_get_file_name(file));

        if (display_name && file_name) {
            fprintf(f, "#EXTINF:-1,%s\n", display_name);
            fprintf(f, "%s\n\n", file_name);
        }
    }

    if (display_name)
        g_free(display_name);

    if (file_name)
        g_free(file_name);

    return TRUE;
}

static gboolean
parole_pl_parser_save_pls(FILE *f, GSList *files) {
    guint len;
    guint i;
    gchar key[128];

    len = g_slist_length(files);

    fprintf(f, "[playlist]\nNumberOfEntries=%d\n", len);

    for (i = 1; i <= len; i++) {
        ParoleFile *file;
        file = g_slist_nth_data(files, i - 1);
        g_snprintf(key, 128, "File%d", i);
        fprintf(f, "%s=%s\n", key, parole_filename_to_utf8(parole_file_get_file_name(file)));
        g_snprintf(key, 128, "Title%d", i);
        fprintf(f, "%s=%s\n\n", key, parole_file_get_display_name(file));
    }

    return TRUE;
}

static gboolean
parole_pl_parser_save_asx(FILE *f, GSList *files) {
    guint len;
    guint i;

    len = g_slist_length(files);

    fputs("<ASX VERSION=\"3.0\">\n", f);

    for (i = 0; i < len; i++) {
        ParoleFile *file;
        file = g_slist_nth_data(files, i);
        fprintf(f, "  <ENTRY>\n   <TITLE>%s</TITLE>\n    <REF HREF=\"%s\"/>\n  </ENTRY>\n",
             parole_file_get_display_name(file),
             parole_file_get_uri(file));
    }

    fputs("</ASX>\n", f);

    return TRUE;
}

static gboolean
parole_pl_parser_save_xspf(FILE *f, GSList *files) {
    guint len;
    guint i;

    len = g_slist_length(files);

    fputs("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
       "<playlist version=\"1\" xmlns=\"http://xspf.org/ns/0/\">\n", f);

    fputs(" <trackList>\n", f);

    for (i = 0; i < len; i++) {
        ParoleFile *file;

        file = g_slist_nth_data(files, i);
        fprintf(f, "  <track>\n    <title>%s</title>\n    <location>%s</location>\n  </track>\n",
             parole_file_get_display_name(file), parole_file_get_uri(file));
    }

    fputs(" </trackList>\n<playlist>", f);

    return TRUE;
}

/**
 * parole_pl_parser_guess_format_from_extension:
 * @filename: a filename
 *
 * Guess a playlist format from the filename extension.
 *
 * Returns: PAROLE_PL_FORMAT_UNKNOWN if unable to get the playlist format, and a valid
 *          playlist format otherwise
 *
 * Since: 0.2
 */
ParolePlFormat
parole_pl_parser_guess_format_from_extension(const gchar *filename) {
    if ( g_str_has_suffix (filename, ".m3u") || g_str_has_suffix (filename, ".M3U") )
        return PAROLE_PL_FORMAT_M3U;

    if ( g_str_has_suffix (filename, ".pls") || g_str_has_suffix (filename, ".PLS") )
        return PAROLE_PL_FORMAT_PLS;

    if ( g_str_has_suffix (filename, ".xspf") || g_str_has_suffix (filename, ".XSPF") )
        return PAROLE_PL_FORMAT_XSPF;

    if ( g_str_has_suffix (filename, ".asx") || g_str_has_suffix (filename, ".ASX") )
        return PAROLE_PL_FORMAT_ASX;

    if ( g_str_has_suffix (filename, ".wax") || g_str_has_suffix (filename, ".WAX") )
        return PAROLE_PL_FORMAT_XSPF;

    return PAROLE_PL_FORMAT_UNKNOWN;
}

/**
 * parole_pl_parser_guess_format_from_data:
 * @filename: a filename
 *
 * Guess a playlist format from its data.
 *
 * Returns: PAROLE_PL_FORMAT_UNKNOWN if unable to get the playlist format, and a valid
 *          playlist format otherwise
 *
 * Since: 0.2
 */
ParolePlFormat
parole_pl_parser_guess_format_from_data(const gchar *filename) {
    GFile *file;
    gchar *contents = NULL;
    gsize size;

    ParolePlFormat format = PAROLE_PL_FORMAT_UNKNOWN;

    file = g_file_new_for_path(filename);

    if (!g_file_load_contents(file, NULL, &contents, &size, NULL, NULL)) {
        g_debug("Unable to load content of file=%s", filename);
        goto out;
    }

    if ( strstr (contents, "<ASX VERSION") )
        format = PAROLE_PL_FORMAT_ASX;
    else if ( strstr (contents, "<trackList>") || strstr (contents, "<tracklist>") )
        format = PAROLE_PL_FORMAT_XSPF;
    else if ( strstr (contents, "NumberOfEntries") )
        format = PAROLE_PL_FORMAT_PLS;
    else
        /* try to load the file as M3U*/
        format = PAROLE_PL_FORMAT_M3U;

    g_free(contents);
out:
    g_object_unref(file);
    return format;
}

/**
 * parole_pl_parser_save_from_files:
 * @files: a #GSList list of #ParoleFile files
 * @filename: a filename to save
 * @format: a #ParolePlFormat format of the playlist
 *
 * Saves a #GSList containing a list of #ParoleFile files to filename.
 *
 *
 * Returns: TRUE if the playlist was saved, FALSE otherwise
 *
 * Since: 0.2
 **/
gboolean parole_pl_parser_save_from_files(GSList *files, const gchar *filename, ParolePlFormat format) {
    FILE *f;
    gboolean ret_val = FALSE;

    PAROLE_DEBUG_ENUM_FULL(format, PAROLE_ENUM_TYPE_PL_FORMAT, "Saving playlist %s ", filename);

    f = fopen(filename, "w");

    switch (format) {
        case PAROLE_PL_FORMAT_M3U:
            ret_val = parole_pl_parser_save_m3u(f, files);
            break;
        case PAROLE_PL_FORMAT_PLS:
            ret_val = parole_pl_parser_save_pls(f, files);
            break;
        case PAROLE_PL_FORMAT_ASX:
            ret_val = parole_pl_parser_save_asx(f, files);
            break;
        case PAROLE_PL_FORMAT_XSPF:
            ret_val = parole_pl_parser_save_xspf(f, files);
            break;
        default:
            break;
    }

    fclose(f);

    return ret_val;
}

/**
 * parole_pl_parser_parse_from_file_by_extension:
 * @filename: a filename
 *
 * Parse a playlist into a series of #ParoleFile
 *
 * Returns: a #GSList containing a list of #ParoleFile parsed from the playlist,
 *          or NULL if no files were parsed
 *
 * Since: 0.2
 */
GSList *parole_pl_parser_parse_from_file_by_extension(const gchar *filename) {
    ParolePlFormat format = PAROLE_PL_FORMAT_UNKNOWN;
    GSList *list = NULL;

    if ( (format = parole_pl_parser_guess_format_from_extension (filename)) == PAROLE_PL_FORMAT_UNKNOWN &&
(format = parole_pl_parser_guess_format_from_data(filename)) == PAROLE_PL_FORMAT_UNKNOWN ) {
        g_debug("Unable to guess playlist format : %s", filename);
        goto out;
    }

    PAROLE_DEBUG_ENUM_FULL(format, PAROLE_ENUM_TYPE_PL_FORMAT, "playlist %s ", filename);
    list = parole_pl_parser_parse(format, filename);

out:
    return list;
}

/**
 * parole_pl_parser_parse_all_from_file:
 * @filename: a filename
 *
 * This function tries to parse a playlist without guessing the playlist format.
 *
 *
 * Returns: a #GSList containing a list of #ParoleFile parsed from the playlist,
 *          or NULL if no files were parsed
 *
 * Since: 0.2
 */
GSList *parole_pl_parser_parse_all_from_file(const gchar *filename) {
    GSList *list = NULL;

    list = parole_pl_parser_parse_asx(filename);
    list = g_slist_concat(list, parole_pl_parser_parse_m3u(filename));
    list = g_slist_concat(list, parole_pl_parser_parse_pls(filename));
    list = g_slist_concat(list, parole_pl_parser_parse_xspf(filename));

    return list;
}

/**
 * parole_pl_parser_can_parse_data:
 * @data: data
 * @len: length of data
 *
 * Get if the Parole parser can parse from the passed data.
 *
 * Returns: TRUE if it can parse from the data, FALSE otherwise
 *
 * Since: 0.2
 */
gboolean parole_pl_parser_can_parse_data(const guchar *data, gint len) {
    gchar *mime_type = NULL;
    gboolean result_uncertain;
    gboolean result = FALSE;

    mime_type = g_content_type_guess(NULL, data, len,  &result_uncertain);

    if ( mime_type && result_uncertain == FALSE ) {
        GtkFileFilter *filter = g_object_ref_sink(parole_get_supported_playlist_filter());
        GtkFileFilterInfo filter_info;
        g_debug("Mime_type=%s", mime_type);
        filter_info.mime_type = mime_type;

        filter_info.contains = GTK_FILE_FILTER_MIME_TYPE;

        result = gtk_file_filter_filter(filter, &filter_info);
        g_object_unref(filter);
        g_free(mime_type);
    }

    return result;
}
