<?php

// Pandora FMS - http://pandorafms.com
// ==================================================
// Copyright (c) 2005-2021 Artica Soluciones Tecnologicas
// Please see http://pandorafms.org for full contribution list
// This program is free software; you can redistribute it and/or
// modify it under the terms of the  GNU Lesser General Public License
// as published by the Free Software Foundation; version 2
// 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.


/**
 * Connect db
 *
 * @param string $host    Host.
 * @param string $db      Db.
 * @param string $user    User.
 * @param string $pass    Pass.
 * @param string $port    Port.
 * @param string $charset Charset.
 *
 * @return mysqli|false
 */
function mysql_connect_db(
    $host=null,
    $db=null,
    $user=null,
    $pass=null,
    $port=null,
    $charset=null,
    $ssl=null,
    $verify=null
) {
    global $config;

    if ($host === null) {
        $host = $config['dbhost'];
    }

    if ($db === null) {
        $db = $config['dbname'];
    }

    if ($user === null) {
        $user = $config['dbuser'];
    }

    if ($pass === null) {
        $pass = $config['dbpass'];
    }

    if ($port === null) {
        $port = $config['dbport'];
    }

    if ($ssl === null && (bool) $config['dbssl'] === true) {
        $ssl = $config['dbsslcafile'];
    }

    if ($verify === null && (bool) $config['sslverifyservercert'] === true) {
        $verify = 'verified';
    }

    // Check if mysqli is available
    if (!isset($config['mysqli'])) {
        $config['mysqli'] = extension_loaded(mysqli);
    }

    // Non-persistent connection: This will help to avoid mysql errors like "has gone away" or locking problems
    // If you want persistent connections change it to mysql_pconnect().
    if ($config['mysqli']) {
        if (empty($ssl)) {
            $connect_id = mysqli_connect($host, $user, $pass, $db, $port);
            if (mysqli_connect_errno() > 0) {
                include 'general/mysqlerr.php';
                return false;
            }

            db_change_cache_id($db, $host);

            if (isset($charset)) {
                mysqli_set_charset($connect_id, $charset);
            }

            mysqli_select_db($connect_id, $db);
        } else {
            $connect_id = mysqli_init();

            mysqli_ssl_set($connect_id, null, null, $ssl, null, null);

            if ($verify === 'verified') {
                mysqli_real_connect($connect_id, $host, $user, $pass, $db, $port, null, MYSQLI_CLIENT_SSL);
            } else {
                mysqli_real_connect($connect_id, $host, $user, $pass, $db, $port, null, MYSQLI_CLIENT_SSL_DONT_VERIFY_SERVER_CERT);
            }

            if (mysqli_connect_errno() > 0) {
                include 'general/mysqlerr.php';
                return false;
            }
        }
    } else {
        $connect_id = @mysql_connect($host.':'.$port, $user, $pass, true);
        if (!$connect_id) {
            return false;
        }

        db_change_cache_id($db, $host);

        if (isset($charset)) {
            @mysql_set_charset($connect_id, $charset);
        }

        mysql_select_db($db, $connect_id);
    }

    return $connect_id;
}


function mysql_db_get_all_rows_sql($sql, $search_history_db=false, $cache=true, $dbconnection=false)
{
    global $config;

    $history = [];

    if ($dbconnection === false) {
        $dbconnection = $config['dbconnection'];
    }

    // To disable globally SQL cache depending on global variable.
    // Used in several critical places like Metaconsole trans-server queries
    if (isset($config['dbcache'])) {
        $cache = $config['dbcache'];
    }

    // Read from the history DB if necessary
    if ($search_history_db && $config['history_db_enabled'] == 1) {
        $cache = false;
        $history = false;

        // Connect to the history DB
        if (!isset($config['history_db_connection']) || $config['history_db_connection'] === false) {
            $config['history_db_connection'] = db_connect($config['history_db_host'], $config['history_db_name'], $config['history_db_user'], io_output_password($config['history_db_pass']), $config['history_db_port'], false);
        }

        if ($config['history_db_connection'] !== false) {
            $history = mysql_db_process_sql($sql, 'affected_rows', $config['history_db_connection'], false);
        }

        if ($history === false) {
            $history = [];
        }
    }

    $return = mysql_db_process_sql(
        $sql,
        'affected_rows',
        $dbconnection,
        $cache
    );

    if ($return === false) {
        $return = [];
    }

    // Append result to the history DB data
    if (!empty($return)) {
        foreach ($return as $row) {
            array_push($history, $row);
        }
    }

    if (!empty($history)) {
        return $history;
    }

    // Return false, check with === or !==
    return false;
}


/**
 * Get the first value of the first row of a table in the database.
 *
 * @param string  $field             Field name to get.
 * @param string  $table             Table to retrieve the data.
 * @param string  $field_search      Field to filter elements.
 * @param string  $condition         Condition the field must have.
 * @param boolean $search_history_db Search in historical db.
 * @param boolean $cache             Enable cache or not.
 *
 * @return mixed Value of first column of the first row. False if there were no row.
 */
function mysql_db_get_value(
    $field,
    $table,
    $field_search=1,
    $condition=1,
    $search_history_db=false,
    $cache=true
) {
    if (is_int($condition)) {
        $sql = sprintf(
            'SELECT %s FROM %s WHERE %s = %d LIMIT 1',
            $field,
            $table,
            $field_search,
            $condition
        );
    } else if (is_float($condition) || is_double($condition)) {
        $sql = sprintf(
            'SELECT %s FROM %s WHERE %s = %f LIMIT 1',
            $field,
            $table,
            $field_search,
            $condition
        );
    } else {
        $sql = sprintf(
            "SELECT %s FROM %s WHERE %s = '%s' LIMIT 1",
            $field,
            $table,
            $field_search,
            $condition
        );
    }

    $result = db_get_all_rows_sql($sql, $search_history_db, $cache);

    if ($result === false) {
        return false;
    }

    $row = array_shift($result);
    $value = array_shift($row);

    if ($value === null) {
        return false;
    }

    return $value;
}


/**
 * Get the first row of a database query into a table.
 *
 * The SQL statement executed would be something like:
 * "SELECT (*||$fields) FROM $table WHERE $field_search = $condition"
 *
 * @param string Table to get the row
 * @param string Field to filter elements
 * @param string Condition the field must have.
 * @param mixed Fields to select (array or string or false/empty for *)
 *
 * @return mixed The first row of a database query or false.
 */
function mysql_db_get_row($table, $field_search, $condition, $fields=false, $cache=true)
{
    if (empty($fields)) {
        $fields = '*';
    } else {
        if (is_array($fields)) {
            $fields = implode(',', $fields);
        } else if (!is_string($fields)) {
            return false;
        }
    }

    if (is_int($condition)) {
        $sql = sprintf(
            'SELECT %s FROM `%s` WHERE `%s` = %d LIMIT 1',
            $fields,
            $table,
            $field_search,
            $condition
        );
    } else if (is_float($condition) || is_double($condition)) {
        $sql = sprintf(
            'SELECT %s FROM `%s` WHERE `%s` = %f LIMIT 1',
            $fields,
            $table,
            $field_search,
            $condition
        );
    } else {
        $sql = sprintf(
            "SELECT %s FROM `%s` WHERE `%s` = '%s' LIMIT 1",
            $fields,
            $table,
            $field_search,
            $condition
        );
    }

    $result = db_get_all_rows_sql($sql, false, $cache);

    if ($result === false) {
        return false;
    }

    return $result[0];
}


/**
 * Get all the rows in a table of the database.
 *
 * @param string Database table name.
 * @param string Field to order by.
 * @param string                     $order The type of order, by default 'ASC'.
 *
 * @return mixed A matrix with all the values in the table
 */
function mysql_db_get_all_rows_in_table($table, $order_field='', $order='ASC')
{
    $sql = '
		SELECT *
		FROM `'.$table.'`';

    if (!empty($order_field)) {
        if (is_array($order_field)) {
            foreach ($order_field as $i => $o) {
                $order_field[$i] = $o.' '.$order;
            }

            $sql .= '
				ORDER BY '.implode(',', $order_field);
        } else {
            $sql .= '
				ORDER BY '.$order_field.' '.$order;
        }
    }

    return db_get_all_rows_sql($sql);
}


/**
 * Inserts strings into database
 *
 * The number of values should be the same or a positive integer multiple as the number of rows
 * If you have an associate array (eg. array ("row1" => "value1")) you can use this function with ($table, array_keys ($array), $array) in it's options
 * All arrays and values should have been cleaned before passing. It's not neccessary to add quotes.
 *
 * @param string Table to insert into
 * @param mixed A single value or array of values to insert (can be a multiple amount of rows)
 *
 * @return mixed False in case of error or invalid values passed. Affected rows otherwise
 */
function mysql_db_process_sql_insert($table, $values)
{
    // Empty rows or values not processed
    if (empty($values)) {
        return false;
    }

    $values = (array) $values;

    $query = sprintf('INSERT INTO `%s` ', $table);
    $fields = [];
    $values_str = '';
    $i = 1;
    $max = count($values);
    foreach ($values as $field => $value) {
        // Add the correct escaping to values
        if ($field[0] != '`') {
            $field = '`'.$field.'`';
        }

        array_push($fields, $field);

        if (is_null($value)) {
            $values_str .= 'NULL';
        } else if (is_int($value) || is_bool($value)) {
            $values_str .= sprintf('%d', $value);
        } else if (is_float($value) || is_double($value)) {
            $values_str .= sprintf('%f', $value);
        } else {
            $values_str .= sprintf("'%s'", $value);
        }

        if ($i < $max) {
            $values_str .= ',';
        }

        $i++;
    }

    $query .= '('.implode(', ', $fields).')';

    $query .= ' VALUES ('.$values_str.')';

    return db_process_sql($query, 'insert_id');
}


/**
 * This function comes back with an array in case of SELECT
 * in case of UPDATE, DELETE etc. with affected rows
 * an empty array in case of SELECT without results
 * Queries that return data will be cached so queries don't get repeated
 *
 * @param string SQL statement to execute
 *
 * @param string What type of info to return in case of INSERT/UPDATE.
 *        'affected_rows' will return mysql_affected_rows (default value)
 *        'insert_id' will return the ID of an autoincrement value
 *        'info' will return the full (debug) information of a query
 *
 * @return mixed An array with the rows, columns and values in a multidimensional array or false in error
 */
function mysql_db_process_sql($sql, $rettype='affected_rows', $dbconnection='', $cache=true)
{
    global $config;
    global $sql_cache;

    $retval = [];

    if ($sql == '') {
        return false;
    }

    if (isset($config['dbcache']) === true) {
        $cache = $config['dbcache'];
    }

    if ($cache && !empty($sql_cache[$sql_cache['id']][$sql])) {
        $retval = $sql_cache[$sql_cache['id']][$sql];
        $sql_cache['saved'][$sql_cache['id']]++;
        db_add_database_debug_trace($sql);
    } else {
        $start = microtime(true);

        if ($dbconnection == '') {
            $dbconnection = $config['dbconnection'];
        }

        if ($config['mysqli'] === true) {
            $result = mysqli_query($dbconnection, $sql);
        } else {
            $result = mysql_query($sql, $dbconnection);
        }

        $time = (microtime(true) - $start);
        if ($result === false) {
            $backtrace = debug_backtrace();
            if ($config['mysqli'] === true) {
                $error = sprintf(
                    '%s (\'%s\') in <strong>%s</strong> on line %d',
                    mysqli_error($dbconnection),
                    $sql,
                    $backtrace[0]['file'],
                    $backtrace[0]['line']
                );
                db_add_database_debug_trace($sql, mysqli_error($dbconnection));
            } else {
                $error = sprintf(
                    '%s (\'%s\') in <strong>%s</strong> on line %d',
                    mysql_error(),
                    $sql,
                    $backtrace[0]['file'],
                    $backtrace[0]['line']
                );
                db_add_database_debug_trace($sql, mysql_error($dbconnection));
            }

            set_error_handler('db_sql_error_handler');
            trigger_error($error);
            restore_error_handler();
            return false;
        } else if ($result === true) {
            if ($config['mysqli'] === true) {
                if ($rettype == 'insert_id') {
                    $result = mysqli_insert_id($dbconnection);
                } else if ($rettype == 'info') {
                    $result = mysqli_info($dbconnection);
                } else {
                    $result = mysqli_affected_rows($dbconnection);
                }

                db_add_database_debug_trace(
                    $sql,
                    $result,
                    mysqli_affected_rows($dbconnection),
                    ['time' => $time]
                );
            } else {
                if ($rettype == 'insert_id') {
                    $result = mysql_insert_id($dbconnection);
                } else if ($rettype == 'info') {
                    $result = mysql_info($dbconnection);
                } else {
                    $result = mysql_affected_rows($dbconnection);
                }

                db_add_database_debug_trace(
                    $sql,
                    $result,
                    mysql_affected_rows($dbconnection),
                    ['time' => $time]
                );
            }

            return $result;
        } else {
            if ($config['mysqli'] === true) {
                db_add_database_debug_trace(
                    $sql,
                    0,
                    mysqli_affected_rows($dbconnection),
                    ['time' => $time]
                );
                while ($row = mysqli_fetch_assoc($result)) {
                    array_push($retval, $row);
                }

                if ($cache === true) {
                    $sql_cache[$sql_cache['id']][$sql] = $retval;
                }

                mysqli_free_result($result);
            } else {
                db_add_database_debug_trace(
                    $sql,
                    0,
                    mysql_affected_rows($dbconnection),
                    ['time' => $time]
                );
                while ($row = mysql_fetch_assoc($result)) {
                    array_push($retval, $row);
                }

                if ($cache === true) {
                    $sql_cache[$sql_cache['id']][$sql] = $retval;
                }

                mysql_free_result($result);
            }
        }
    }

    if (!empty($retval)) {
        return $retval;
    }

    // Return false, check with === or !==
    return false;
}


/**
 * Escape string to set it properly to use in sql queries
 *
 * @param string String to be cleaned.
 *
 * @return string String cleaned.
 */
function mysql_escape_string_sql($string)
{
    global $config;

    $dbconnection = $config['dbconnection'];
    if ($dbconnection == null) {
        $dbconnection = mysql_connect_db();
    }

    if ($config['mysqli'] === true) {
        $str = mysqli_real_escape_string($dbconnection, $string);
    } else {
        $str = mysql_real_escape_string($string);
    }

    return $str;
}


function mysql_encapsule_fields_with_same_name_to_instructions($field)
{
    $return = $field;

    if (is_string($return)) {
        if ($return[0] !== '`') {
            $return = '`'.$return.'`';
        }
    }

    return $return;
}


/**
 * Get the first value of the first row of a table in the database from an
 * array with filter conditions.
 *
 * Example:
 <code>
 db_get_value_filter ('name', 'talert_templates',
 array ('value' => 2, 'type' => 'equal'));
 // Equivalent to:
 // SELECT name FROM talert_templates WHERE value = 2 AND type = 'equal' LIMIT 1

 db_get_value_filter ('description', 'talert_templates',
 array ('name' => 'My alert', 'type' => 'regex'), 'OR');
 // Equivalent to:
 // SELECT description FROM talert_templates WHERE name = 'My alert' OR type = 'equal' LIMIT 1
 </code>
 *
 * @param string Field name to get
 * @param string Table to retrieve the data
 * @param array Conditions to filter the element. See db_format_array_where_clause_sql()
 * for the format
 * @param string Join operator for the elements in the filter.
 *
 * @return mixed Value of first column of the first row. False if there were no row.
 */
function mysql_db_get_value_filter($field, $table, $filter, $where_join='AND', $search_history_db=false)
{
    if (!is_array($filter) || empty($filter)) {
        return false;
    }

    // Avoid limit and offset if given
    unset($filter['limit']);
    unset($filter['offset']);

    $sql = sprintf(
        'SELECT %s FROM %s WHERE %s LIMIT 1',
        $field,
        $table,
        db_format_array_where_clause_sql($filter, $where_join)
    );

    $result = db_get_all_rows_sql($sql, $search_history_db);

    if ($result === false) {
        return false;
    }

    $row = array_shift($result);
    $value = array_shift($row);

    if ($value === null) {
        return false;
    }

    return $value;
}


/**
 * Formats an array of values into a SQL where clause string.
 *
 * This function is useful to generate a WHERE clause for a SQL sentence from
 * a list of values. Example code:
 <code>
 $values = array ();
 $values['name'] = "Name";
 $values['description'] = "Long description";
 $values['limit'] = $config['block_size']; // Assume it's 20
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values);
 echo $sql;
 </code>
 * Will return:
 * <code>
 * SELECT * FROM table WHERE `name` = "Name" AND `description` = "Long description" LIMIT 20
 * </code>
 *
 * @param array Values to be formatted in an array indexed by the field name.
 * There are special parameters such as 'limit' and 'offset' that will be used
 * as ORDER, LIMIT and OFFSET clauses respectively. Since LIMIT and OFFSET are
 * numerics, ORDER can receive a field name or a SQL function and a the ASC or
 * DESC clause. Examples:
 <code>
 $values = array ();
 $values['value'] = 10;
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values);
 // SELECT * FROM table WHERE VALUE = 10

 $values = array ();
 $values['value'] = 10;
 $values['order'] = 'name DESC';
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values);
 // SELECT * FROM table WHERE VALUE = 10 ORDER BY name DESC

 </code>
 * @param string Join operator. AND by default.
 * @param string A prefix to be added to the string. It's useful when limit and
 * offset could be given to avoid this cases:
 <code>
 $values = array ();
 $values['limit'] = 10;
 $values['offset'] = 20;
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values);
 // Wrong SQL: SELECT * FROM table WHERE LIMIT 10 OFFSET 20

 $values = array ();
 $values['limit'] = 10;
 $values['offset'] = 20;
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values, 'AND', 'WHERE');
 // Good SQL: SELECT * FROM table LIMIT 10 OFFSET 20

 $values = array ();
 $values['value'] = 5;
 $values['limit'] = 10;
 $values['offset'] = 20;
 $sql = 'SELECT * FROM table WHERE '.db_format_array_where_clause_sql ($values, 'AND', 'WHERE');
 // Good SQL: SELECT * FROM table WHERE value = 5 LIMIT 10 OFFSET 20
 </code>
 *
 * @return string Values joined into an SQL string that can fits into the WHERE
 * clause of an SQL sentence.
 */
function mysql_db_format_array_where_clause_sql($values, $join='AND', $prefix=false)
{
    $fields = [];

    if (!is_array($values)) {
        return '';
    }

    $query = '';
    $limit = '';
    $offset = '';
    $order = '';
    $group = '';
    if (isset($values['limit'])) {
        $limit = sprintf(' LIMIT %d', $values['limit']);
        unset($values['limit']);
    }

    if (isset($values['offset'])) {
        $offset = sprintf(' OFFSET %d', $values['offset']);
        unset($values['offset']);
    }

    if (isset($values['order'])) {
        if (is_array($values['order'])) {
            if (!isset($values['order']['order'])) {
                $orderTexts = [];
                foreach ($values['order'] as $orderItem) {
                    $orderTexts[] = $orderItem['field'].' '.$orderItem['order'];
                }

                $order = ' ORDER BY '.implode(', ', $orderTexts);
            } else {
                $order = sprintf(' ORDER BY %s %s', $values['order']['field'], $values['order']['order']);
            }
        } else {
            $order = sprintf(' ORDER BY %s', $values['order']);
        }

        unset($values['order']);
    }

    if (isset($values['group'])) {
        $group = sprintf(' GROUP BY %s', $values['group']);
        unset($values['group']);
    }

    $i = 1;
    $max = count($values);
    foreach ($values as $field => $value) {
        $negative = false;
        if (is_numeric($field)) {
            // User provide the exact operation to do
            $query .= $value;

            if ($i < $max) {
                $query .= ' '.$join.' ';
            }

            $i++;
            continue;
        }

        if ($field[0] == '!') {
            $negative = true;
            $field = substr($field, 1);
        }

        if ($field[0] != '`') {
            // If the field is as <table>.<field>, don't scape.
            if (strstr($field, '.') === false) {
                if (preg_match('/(UPPER|LOWER)(.+)/mi', $field)) {
                    $field = preg_replace('/(UPPER|LOWER])\((.+)\)/mi', '$1(`$2`)', $field);
                } else {
                    $field = '`'.$field.'`';
                }
            }
        }

        if ($value === null) {
            $not = (($negative === true) ? 'NOT' : '');
            $query .= sprintf('%s IS %s NULL', $field, $not);
        } else if (is_int($value) || is_bool($value)) {
            $not = (($negative === true) ? '!' : '');
            $query .= sprintf('%s %s= %d', $field, $not, $value);
        } else if (is_float($value) || is_double($value)) {
            $not = (($negative === true) ? ' !' : '');
            $query .= sprintf('%s %s= %f', $field, $not, $value);
        } else if (is_array($value)) {
            $values_check = array_keys($value);
            $ranges = false;
            $initialized = false;
            foreach ($values_check as $operation) {
                if ($ranges === true && $initialized === true) {
                    $query .= ' '.$join.' ';
                } else {
                    $initialized = true;
                }

                if ($operation === '>') {
                    $query .= sprintf("%s > '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($operation === '>=') {
                    $query .= sprintf("%s >= '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($operation === '<') {
                    $query .= sprintf("%s < '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($operation === '<=') {
                    $query .= sprintf("%s <= '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($operation === '!=') {
                    $query .= sprintf("%s != '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($operation === '=') {
                    $query .= sprintf("%s = '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '>') {
                    $query .= sprintf("%s <= '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '>=') {
                    $query .= sprintf("%s < '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '<') {
                    $query .= sprintf("%s >= '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '<=') {
                    $query .= sprintf("%s > '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '!=') {
                    $query .= sprintf("%s = '%s'", $field, $value[$operation]);
                    $ranges = true;
                } else if ($negative === true && $operation === '=') {
                    $query .= sprintf("%s != '%s'", $field, $value[$operation]);
                    $ranges = true;
                }
            }

            if ($ranges !== true) {
                $not = (($negative === true) ? 'NOT' : '');
                $query .= sprintf('%s %s IN ("%s")', $field, $not, implode('", "', $value));
            }
        } else {
            if ($value === '') {
                // Search empty string.
                $not = (($negative === true) ? '!' : '');
                $query .= sprintf("%s %s= ''", $field, $not);
            } else if ($value[0] == '>') {
                $value = substr($value, 1, (strlen($value) - 1));
                $query .= sprintf("%s > '%s'", $field, $value);
            } else if ($value[0] == '<') {
                if ($value[1] == '>') {
                    $value = substr($value, 2, (strlen($value) - 2));
                    $query .= sprintf("%s <> '%s'", $field, $value);
                } else {
                    $value = substr($value, 1, (strlen($value) - 1));
                    $query .= sprintf("%s < '%s'", $field, $value);
                }
            } else if ($value[0] == '%') {
                $not = (($negative === true) ? ' NOT ' : '');
                $query .= sprintf("%s %s LIKE '%s'", $field, $not, $value);
            } else {
                $not = (($negative === true) ? '!' : '');
                $query .= sprintf("%s %s= '%s'", $field, $not, $value);
            }
        }

        if ($i < $max) {
            $query .= ' '.$join.' ';
        }

        $i++;
    }

    return (!empty($query) ? $prefix : '').$query.$group.$order.$limit.$offset;
}


/**
 * Get the first value of the first row of a table result from query.
 *
 * @param string SQL select statement to execute.
 *
 * @return the first value of the first row of a table result from query.
 */
function mysql_db_get_value_sql($sql, $dbconnection=false, $search_history_db=false)
{
    $sql .= ' LIMIT 1';
    $result = mysql_db_get_all_rows_sql($sql, $search_history_db, true, $dbconnection);

    if ($result === false) {
        return false;
    }

    $row = array_shift($result);
    $value = array_shift($row);

    if ($value === null) {
        return false;
    }

    return $value;
}


/**
 * Get the first row of an SQL database query.
 *
 * @param string SQL select statement to execute.
 *
 * @return mixed The first row of the result or false
 */
function mysql_db_get_row_sql($sql, $search_history_db=false, $cache=true)
{
    $sql .= ' LIMIT 1';
    $result = db_get_all_rows_sql($sql, $search_history_db, $cache);

    if ($result === false) {
        return false;
    }

    return $result[0];
}


/**
 * Get the row of a table in the database using a complex filter.
 *
 * @param string Table to retrieve the data (warning: not cleaned)
 * @param mixed Filters elements. It can be an indexed array
 * (keys would be the field name and value the expected value, and would be
 * joined with an AND operator) or a string, including any SQL clause (without
 * the WHERE keyword). Example:
 <code>
 Both are similars:
 db_get_row_filter ('table', array ('disabled', 0));
 db_get_row_filter ('table', 'disabled = 0');

 Both are similars:
 db_get_row_filter ('table', array ('disabled' => 0, 'history_data' => 0), 'name, description', 'OR');
 db_get_row_filter ('table', 'disabled = 0 OR history_data = 0', 'name, description');
 db_get_row_filter ('table', array ('disabled' => 0, 'history_data' => 0), array ('name', 'description'), 'OR');
 </code>
 * @param mixed Fields of the table to retrieve. Can be an array or a coma
 * separated string. All fields are retrieved by default
 * @param string Condition to join the filters (AND, OR).
 *
 * @return mixed Array of the row or false in case of error.
 */
function mysql_db_get_row_filter($table, $filter, $fields=false, $where_join='AND', $historydb=false, $cache=true)
{
    if (empty($fields)) {
        $fields = '*';
    } else {
        if (is_array($fields)) {
            $fields = implode(',', $fields);
        } else if (!is_string($fields)) {
            return false;
        }
    }

    if (is_array($filter)) {
        $filter = db_format_array_where_clause_sql($filter, $where_join, ' WHERE ');
    } else if (is_string($filter)) {
        $filter = 'WHERE '.$filter;
    } else {
        $filter = '';
    }

    $sql = sprintf('SELECT %s FROM %s %s', $fields, $table, $filter);

    return db_get_row_sql($sql, $historydb, $cache);
}


/**
 * Get all the rows of a table in the database that matches a filter.
 *
 * @param string Table to retrieve the data (warning: not cleaned)
 * @param mixed Filters elements. It can be an indexed array
 * (keys would be the field name and value the expected value, and would be
 * joined with an AND operator) or a string, including any SQL clause (without
 * the WHERE keyword). Example:
 * <code>
 * Both are similars:
 * db_get_all_rows_filter ('table', array ('disabled', 0));
 * db_get_all_rows_filter ('table', 'disabled = 0');
 *
 * Both are similars:
 * db_get_all_rows_filter ('table', array ('disabled' => 0, 'history_data' => 0), 'name', 'OR');
 * db_get_all_rows_filter ('table', 'disabled = 0 OR history_data = 0', 'name');
 * </code>
 * @param mixed Fields of the table to retrieve. Can be an array or a coma
 * separated string. All fields are retrieved by default
 * @param string Condition of the filter (AND, OR).
 * @param boolean                                                  $returnSQL Return a string with SQL instead the data, by default false.
 *
 * @return mixed Array of the row or false in case of error.
 */
function mysql_db_get_all_rows_filter($table, $filter=[], $fields=false, $where_join='AND', $search_history_db=false, $returnSQL=false)
{
    // TODO: Validate and clean fields
    if (empty($fields)) {
        $fields = '*';
    } else if (is_array($fields)) {
        $fields = implode(',', $fields);
    } else if (!is_string($fields)) {
        return false;
    }

    // TODO: Validate and clean filter options
    if (is_array($filter)) {
        $filter = db_format_array_where_clause_sql($filter, $where_join, ' WHERE ');
    } else if (is_string($filter)) {
        $filter = 'WHERE '.$filter;
    } else {
        $filter = '';
    }

    $sql = sprintf(
        'SELECT %s
		FROM %s %s',
        $fields,
        $table,
        $filter
    );

    if ($returnSQL) {
        return $sql;
    } else {
        return db_get_all_rows_sql($sql, $search_history_db);
    }
}


/**
 * Return the count of rows of query.
 *
 * @param  $sql
 * @return integer The count of rows of query.
 */
function mysql_db_get_num_rows($sql)
{
    global $config;

    if ($config['mysqli'] === true) {
        $result = mysqli_query($config['dbconnection'], $sql);

        if ($result) {
            return mysqli_num_rows($result);
        }
    } else {
        $result = mysql_query($sql, $config['dbconnection']);

        if ($result) {
            return mysql_num_rows($result);
        }
    }

    return 0;
}


/**
 * Get all the rows in a table of the databes filtering from a field.
 *
 * @param string Database table name.
 * @param string Field of the table.
 * @param string Condition the field must have to be selected.
 * @param string Field to order by.
 *
 * @return mixed A matrix with all the values in the table that matches the condition in the field or false
 */
function mysql_db_get_all_rows_field_filter($table, $field, $condition, $order_field='')
{
    if (is_int($condition) || is_bool($condition)) {
        $sql = sprintf('SELECT * FROM `%s` WHERE `%s` = %d', $table, $field, $condition);
    } else if (is_float($condition) || is_double($condition)) {
        $sql = sprintf('SELECT * FROM `%s` WHERE `%s` = %f', $table, $field, $condition);
    } else {
        $sql = sprintf("SELECT * FROM `%s` WHERE `%s` = '%s'", $table, $field, $condition);
    }

    if ($order_field != '') {
        $sql .= sprintf(' ORDER BY %s', $order_field);
    }

    return db_get_all_rows_sql($sql);
}


/**
 * Get all the rows in a table of the databes filtering from a field.
 *
 * @param string Database table name.
 * @param string Field of the table.
 *
 * @return mixed A matrix with all the values in the table that matches the condition in the field
 */
function mysql_db_get_all_fields_in_table($table, $field='', $condition='', $order_field='')
{
    $sql = sprintf('SELECT * FROM `%s`', $table);

    if ($condition != '') {
        $sql .= sprintf(" WHERE `%s` = '%s'", $field, $condition);
    }

    if ($order_field != '') {
        $sql .= sprintf(' ORDER BY %s', $order_field);
    }

    return db_get_all_rows_sql($sql);
}


/**
 * Formats an array of values into a SQL string.
 *
 * This function is useful to generate an UPDATE SQL sentence from a list of
 * values. Example code:
 *
 * <code>
 * $values = array ();
 * $values['name'] = "Name";
 * $values['description'] = "Long description";
 * $sql = 'UPDATE table SET '.format_array_to_update_sql ($values).' WHERE id=1';
 * echo $sql;
 * </code>
 * Will return:
 * <code>
 * UPDATE table SET `name` = "Name", `description` = "Long description" WHERE id=1
 * </code>
 *
 * @param array Values to be formatted in an array indexed by the field name.
 *
 * @return string Values joined into an SQL string that can fits into an UPDATE
 * sentence.
 */
function mysql_db_format_array_to_update_sql($values)
{
    $fields = [];

    foreach ($values as $field => $value) {
        if (is_numeric($field)) {
            array_push($fields, $value);
            continue;
        } else if ($field[0] == '`') {
            $field = str_replace('`', '', $field);
        }

        if ($value === null) {
            $sql = sprintf('`%s` = NULL', $field);
        } else if (is_int($value) || is_bool($value)) {
            $sql = sprintf('`%s` = %d', $field, $value);
        } else if (is_float($value) || is_double($value)) {
            $sql = sprintf('`%s` = %f', $field, $value);
        } else {
            // String
            if (isset($value[0]) && $value[0] == '`') {
                // Don't round with quotes if it references a field
                $sql = sprintf('`%s` = %s', $field, $value);
            } else {
                $sql = sprintf("`%s` = '%s'", $field, $value);
            }
        }

        array_push($fields, $sql);
    }

    return implode(', ', $fields);
}


/**
 * Updates a database record.
 *
 * All values should be cleaned before passing. Quoting isn't necessary.
 * Examples:
 *
 * <code>
 * db_process_sql_update ('table', array ('field' => 1), array ('id' => $id));
 * db_process_sql_update ('table', array ('field' => 1), array ('id' => $id, 'name' => $name));
 * db_process_sql_update ('table', array ('field' => 1), array ('id' => $id, 'name' => $name), 'OR');
 * db_process_sql_update ('table', array ('field' => 2), 'id in (1, 2, 3) OR id > 10');
 * </code>
 *
 * @param string Table to insert into
 * @param array An associative array of values to update
 * @param mixed An associative array of field and value matches. Will be joined
 * with operator specified by $where_join. A custom string can also be provided.
 * If nothing is provided, the update will affect all rows.
 * @param string When a                                         $where parameter is given, this will work as the glue
 *                                         between the fields. "AND" operator will be use by default. Other values might
 *                                         be "OR", "AND NOT", "XOR"
 *
 * @return mixed False in case of error or invalid values passed. Affected rows otherwise
 */
function mysql_db_process_sql_update($table, $values, $where=false, $where_join='AND')
{
    $query = sprintf(
        'UPDATE `%s` SET %s',
        $table,
        db_format_array_to_update_sql($values)
    );

    if ($where) {
        if (is_string($where)) {
            // No clean, the caller should make sure all input is clean, this is a raw function
            $query .= ' WHERE '.$where;
        } else if (is_array($where)) {
            $query .= db_format_array_where_clause_sql($where, $where_join, ' WHERE ');
        }
    }

    return db_process_sql($query);
}


/**
 * Delete database records.
 *
 * All values should be cleaned before passing. Quoting isn't necessary.
 * Examples:
 *
 * <code>
 * db_process_sql_delete ('table', array ('id' => 1));
 * // DELETE FROM table WHERE id = 1
 * db_process_sql_delete ('table', array ('id' => 1, 'name' => 'example'));
 * // DELETE FROM table WHERE id = 1 AND name = 'example'
 * db_process_sql_delete ('table', array ('id' => 1, 'name' => 'example'), 'OR');
 * // DELETE FROM table WHERE id = 1 OR name = 'example'
 * db_process_sql_delete ('table', 'id in (1, 2, 3) OR id > 10');
 * // DELETE FROM table WHERE id in (1, 2, 3) OR id > 10
 * </code>
 *
 * @param string Table to insert into
 * @param array An associative array of values to update
 * @param mixed An associative array of field and value matches. Will be joined
 * with operator specified by $where_join. A custom string can also be provided.
 * If nothing is provided, the update will affect all rows.
 * @param string When a                                         $where parameter is given, this will work as the glue
 *                                         between the fields. "AND" operator will be use by default. Other values might
 *                                         be "OR", "AND NOT", "XOR"
 *
 * @return mixed False in case of error or invalid values passed. Affected rows otherwise
 */
function mysql_db_process_sql_delete($table, $where, $where_join='AND')
{
    if (empty($where)) {
        // Should avoid any mistake that lead to deleting all data
        return false;
    }

    $query = sprintf('DELETE FROM `%s` WHERE ', $table);

    if ($where) {
        if (is_string($where)) {
            /*
                FIXME: Should we clean the string for sanity?
             Who cares if this is deleting data... */
            $query .= $where;
        } else if (is_array($where)) {
            $query .= db_format_array_where_clause_sql($where, $where_join);
        }
    }

    return db_process_sql($query);
}


/**
 * Get row by row the DB by SQL query. The first time pass the SQL query and
 * rest of times pass none for iterate in table and extract row by row, and
 * the end return false.
 *
 * @param  boolean  $new    Default true, if true start to query.
 * @param  resource $result The resource of mysql for access to query.
 * @param  string   $sql
 * @return mixed The row or false in error.
 */
function mysql_db_get_all_row_by_steps_sql($new, &$result, $sql=null)
{
    global $config;

    $new = ($new ?? true);

    if ($config['mysqli'] === true) {
        if ($new == true) {
            $result = mysqli_query($config['dbconnection'], $sql);
        }

        if ($result) {
            return mysqli_fetch_assoc($result);
        }
    } else {
        if ($new == true) {
            $result = mysql_query($sql);
        }

        if ($result) {
            return mysql_fetch_assoc($result);
        }
    }

    return [];
}


/**
 * Get last error.
 *
 * @return string Return the string error.
 */
function mysql_db_get_last_error()
{
    global $config;

    if ($config['mysqli']) {
        return mysqli_error();
    } else {
        return mysql_error();
    }
}


/**
 * This function gets the time from either system or sql based on preference and returns it
 *
 * @return integer Unix timestamp
 */
function mysql_get_system_time()
{
    global $config;

    static $time = 0;

    if ($time != 0) {
        return $time;
    }

    if ($config['timesource'] == 'sql') {
        $time = db_get_sql('SELECT UNIX_TIMESTAMP();');
        if (empty($time)) {
            return time();
        }

        return $time;
    } else {
        return time();
    }
}


/**
 * Get the type of field.
 *
 * @param string  $table The table to examine the type of field.
 * @param integer $field The field order in table.
 *
 * @return mixed Return the type name or False in error case.
 */
function mysql_db_get_type_field_table($table, $field)
{
    global $config;

    if ($config['mysqli']) {
        $result = mysqli_query($config['dbconnection'], 'SELECT parameters FROM '.$table);

        return mysqli_fetch_field_direct($result, $field);
    } else {
        $result = mysql_query('SELECT parameters FROM '.$table);

        return mysql_field_type($result, $field);
    }
}


function mysql_get_fields($table)
{
    global $config;

    return db_get_all_rows_sql('SHOW COLUMNS FROM '.$table);
}


/**
 * Process a file with an oracle schema sentences.
 * Based on the function which installs the pandoradb.sql schema.
 *
 * @param string  $path         File path.
 * @param boolean $handle_error Whether to handle the mysqli_query/mysql_query errors or throw an exception.
 *
 * @return boolean Return the final status of the operation.
 */
function mysql_db_process_file($path, $handle_error=true)
{
    global $config;

    if (file_exists($path)) {
        $file_content = file($path);
        $query = '';

        // Begin the transaction
        db_process_sql_begin();

        foreach ($file_content as $sql_line) {
            if (trim($sql_line) != '' && strpos($sql_line, '--') === false) {
                $query .= $sql_line;

                if (preg_match("/;[\040]*\$/", $sql_line)) {
                    if ($config['mysqli']) {
                        $query_result = mysqli_query($config['dbconnection'], $query);
                    } else {
                        $query_result = mysql_query($query);
                    }

                    if (!$result = $query_result) {
                        // Error. Rollback the transaction
                        db_process_sql_rollback();

                        if ($config['mysqli']) {
                            $error_message = mysqli_error($config['dbconnection']);
                        } else {
                            $error_message = mysql_error();
                        }

                        // Handle the error
                        if ($handle_error) {
                            $backtrace = debug_backtrace();
                            $error = sprintf(
                                '%s (\'%s\') in <strong>%s</strong> on line %d',
                                $error_message,
                                $query,
                                $backtrace[0]['file'],
                                $backtrace[0]['line']
                            );
                            db_add_database_debug_trace($query, $error_message);
                            set_error_handler('db_sql_error_handler');
                            trigger_error($error);
                            restore_error_handler();

                            return false;
                        }
                        // Throw an exception with the error message
                        else {
                            throw new Exception($error_message);
                        }
                    }

                    $query = '';
                }
            }
        }

        // No errors. Commit the transaction
        db_process_sql_commit();
        return true;
    } else {
        return false;
    }
}


// ---------------------------------------------------------------
// Initiates a transaction and run the queries of an sql file
// ---------------------------------------------------------------
function db_run_sql_file($location)
{
    global $config;

    // Load file
    $commands = file_get_contents($location);
    // Delete comments
    $lines = explode("\n", $commands);
    $commands = '';
    foreach ($lines as $line) {
        $line = trim($line);
        if ($line && !preg_match('/^--/', $line) && !preg_match('/^\/\*/', $line)) {
            $line = preg_replace('/;$/', '__;__', $line);
            $commands .= $line;
        }
    }

    // Convert to array
    $commands = explode('__;__', $commands);

    if ($config['mysqli']) {
        $mysqli = new mysqli($config['dbhost'], $config['dbuser'], $config['dbpass'], $config['dbname'], $config['dbport']);

        // Run commands
        $mysqli->query($config['dbconnection'], 'SET AUTOCOMMIT = 0');
        $mysqli->query($config['dbconnection'], 'START TRANSACTION');
    } else {
        // Run commands
        db_process_sql_begin();
        // Begin transaction
    }

    foreach ($commands as $command) {
        if (trim($command)) {
            $command .= ';';

            if ($config['mysqli']) {
                $result = $mysqli->query($command);
            } else {
                $result = mysql_query($command);
            }

            if (!$result) {
                break;
                // Error
            }
        }
    }

    if ($result) {
        if ($config['mysqli']) {
            $mysqli->query($config['dbconnection'], 'COMMIT');
            $mysqli->query($config['dbconnection'], 'SET AUTOCOMMIT = 1');
        } else {
            db_process_sql_commit();
            // Save results
        }

        return true;
    } else {
        if ($config['mysqli']) {
            $mysqli->query($config['dbconnection'], 'ROLLBACK ');
            $mysqli->query($config['dbconnection'], 'SET AUTOCOMMIT = 1');
        } else {
            db_process_sql_rollback();
            // Undo results
        }

        $config['db_run_sql_file_error'] = $mysqli->error;
        return false;
    }
}


/**
 * Inserts multiples strings into database.
 *
 * @param string  $table      Table to insert into.
 * @param mixed   $values     A single value or array of values to insert
 *      (can be a multiple amount of rows).
 * @param boolean $only_query Sql string.
 *
 * @return mixed False in case of error or invalid values passed.
 * Affected rows otherwise.
 */
function mysql_db_process_sql_insert_multiple($table, $values, $only_query)
{
    // Empty rows or values not processed.
    if (empty($values) === true || is_array($values) === false) {
        return false;
    }

    $query = sprintf('INSERT INTO `%s`', $table);

    $j = 1;
    $max_total = count($values);
    foreach ($values as $key => $value) {
        $fields = [];
        $values_str = '';
        $i = 1;
        $max = count($value);
        foreach ($value as $k => $v) {
            if ($j === 1) {
                // Add the correct escaping to values.
                $field = sprintf('`%s`', $k);
                array_push($fields, $field);
            }

            if (isset($v) === false) {
                $values_str .= 'NULL';
            } else if (is_int($v) || is_bool($v)) {
                $values_str .= sprintf('%d', $v);
            } else if (is_float($v) || is_double($v)) {
                $values_str .= sprintf('%f', $v);
            } else {
                $values_str .= sprintf("'%s'", $v);
            }

            if ($i < $max) {
                $values_str .= ',';
            }

            $i++;
        }

        if ($j === 1) {
            $query .= sprintf(' (%s) VALUES', implode(', ', $fields));
        }

        $query .= ' ('.$values_str.')';

        if ($j < $max_total) {
            $query .= ',';
        }

        $j++;
    }

    if ($only_query === true) {
        $result = $query;
    } else {
        $result = db_process_sql($query);
    }

    return $result;
}


/**
 * Updates multiples strings into database.
 *
 * @param string  $table      Table to update into.
 * @param mixed   $values     A single value or array of values to update
 *       (can be a multiple amount of rows).
 * @param boolean $only_query Sql string.
 *
 * @return mixed False in case of error or invalid values passed.
 * Affected rows otherwise.
 */
function mysql_db_process_sql_update_multiple($table, $values, $only_query)
{
    // Empty rows or values not processed.
    if (empty($values) === true || is_array($values) === false) {
        return false;
    }

    $res = [];
    foreach ($values as $field => $update) {
        $query = sprintf('UPDATE `%s` SET', $table);
        $query .= sprintf(' `%s` = CASE `%s`', $field, $field);
        foreach ($update as $where => $set) {
            $query .= sprintf(' WHEN "%s" THEN  "%s"', $where, $set);
        }

        $query .= sprintf(' ELSE `%s` END', $field);
        $query .= sprintf(' WHERE `%s` IN (%s)', $field, '"'.implode('","', array_keys($update)).'"');

        if ($only_query === true) {
            $res[] = $query;
        } else {
            $res['table'] = $table;
            $res['fields'][$field] = db_process_sql($query);
        }
    }

    return $res;
}