/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * 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:
 *
 * Copyright (C) 2008 - 2009 Novell, Inc.
 * Copyright (C) 2009 - 2010 Red Hat, Inc.
 */

#include <glib.h>
#include <string.h>

#include "mm-errors.h"
#include "mm-modem-helpers.h"

GPtrArray *
mm_gsm_parse_scan_response (const char *reply, GError **error)
{
    /* Got valid reply */
    GPtrArray *results = NULL;
    GRegex *r;
    GMatchInfo *match_info;
    GError *err = NULL;
    gboolean umts_format = TRUE;

    g_return_val_if_fail (reply != NULL, NULL);
    if (error)
        g_return_val_if_fail (*error == NULL, NULL);

    if (!strstr (reply, "+COPS: ")) {
        g_set_error_literal (error,
                             MM_MODEM_ERROR, MM_MODEM_ERROR_GENERAL,
                             "Could not parse scan results.");
        return NULL;
    }

    reply = strstr (reply, "+COPS: ") + 7;

    /* Cell access technology (GSM, UTRAN, etc) got added later and not all
        * modems implement it.  Some modesm have quirks that make it hard to
        * use one regular experession for matching both pre-UMTS and UMTS
        * responses.  So try UMTS-format first and fall back to pre-UMTS if
        * we get no UMTS-formst matches.
        */

    /* Quirk: Sony-Ericsson TM-506 sometimes includes a stray ')' like so,
        *        which is what makes it hard to match both pre-UMTS and UMTS in
        *        the same regex:
        *
        *       +COPS: (2,"","T-Mobile","31026",0),(1,"AT&T","AT&T","310410"),0)
        */

    r = g_regex_new ("\\((\\d),\"(.*)\",\"(.*)\",\"(.*)\"[\\)]?,(\\d)\\)", G_REGEX_UNGREEDY, 0, &err);
    if (err) {
        g_error ("Invalid regular expression: %s", err->message);
        g_error_free (err);
        g_set_error_literal (error,
                             MM_MODEM_ERROR, MM_MODEM_ERROR_GENERAL,
                             "Could not parse scan results.");
        return NULL;
    }

    /* If we didn't get any hits, try the pre-UMTS format match */
    if (!g_regex_match (r, reply, 0, &match_info)) {
        g_regex_unref (r);
        if (match_info) {
            g_match_info_free (match_info);
            match_info = NULL;
        }

        /* Pre-UMTS format doesn't include the cell access technology after
            * the numeric operator element.
            *
            * Ex: Motorola C-series (BUSlink SCWi275u) like so:
            *
            *       +COPS: (2,"T-Mobile","","310260"),(0,"Cingular Wireless","","310410")
            */
        r = g_regex_new ("\\((\\d),\"(.*)\",\"(.*)\",\"(.*)\"\\)", G_REGEX_UNGREEDY, 0, &err);
        if (err) {
            g_error ("Invalid regular expression: %s", err->message);
            g_error_free (err);
            g_set_error_literal (error,
                                 MM_MODEM_ERROR, MM_MODEM_ERROR_GENERAL,
                                 "Could not parse scan results.");
            return NULL;
        }

        g_regex_match (r, reply, 0, &match_info);
        umts_format = FALSE;
    }

    /* Parse the results */
    results = g_ptr_array_new ();
    while (g_match_info_matches (match_info)) {
        GHashTable *hash;
        char *access_tech = NULL;

        hash = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
        g_hash_table_insert (hash, g_strdup (MM_SCAN_TAG_STATUS), g_match_info_fetch (match_info, 1));
        g_hash_table_insert (hash, g_strdup (MM_SCAN_TAG_OPER_LONG), g_match_info_fetch (match_info, 2));
        g_hash_table_insert (hash, g_strdup (MM_SCAN_TAG_OPER_SHORT), g_match_info_fetch (match_info, 3));
        g_hash_table_insert (hash, g_strdup (MM_SCAN_TAG_OPER_NUM), g_match_info_fetch (match_info, 4));

        /* Only try for access technology with UMTS-format matches */
        if (umts_format)
            access_tech = g_match_info_fetch (match_info, 5);
        if (access_tech && (strlen (access_tech) == 1)) {
            /* Recognized access technologies are between '0' and '6' inclusive... */
            if ((access_tech[0] >= 48) && (access_tech[0] <= 54))
                g_hash_table_insert (hash, g_strdup (MM_SCAN_TAG_ACCESS_TECH), access_tech);
        } else
            g_free (access_tech);

        g_ptr_array_add (results, hash);

        g_match_info_next (match_info, NULL);
    }

    g_match_info_free (match_info);
    g_regex_unref (r);

    return results;
}

void
mm_gsm_destroy_scan_data (gpointer data)
{
    GPtrArray *results = (GPtrArray *) data;

    g_ptr_array_foreach (results, (GFunc) g_hash_table_destroy, NULL);
    g_ptr_array_free (results, TRUE);
}