<?php
/* vim: set expandtab sw=4 ts=4 sts=4: */
/**
 * Functions for trigger management.
 *
 * @package PhpMyAdmin
 */
if (! defined('PHPMYADMIN')) {
    exit;
}

/**
 * Sets required globals
 *
 * @return void
 */
function PMA_TRI_setGlobals()
{
    global $action_timings, $event_manipulations;

    // Some definitions for triggers
    $action_timings      = array('BEFORE',
                                 'AFTER');
    $event_manipulations = array('INSERT',
                                 'UPDATE',
                                 'DELETE');
}

/**
 * Main function for the triggers functionality
 *
 * @return void
 */
function PMA_TRI_main()
{
    global $db, $table;

    PMA_TRI_setGlobals();
    /**
     * Process all requests
     */
    PMA_TRI_handleEditor();
    PMA_TRI_handleExport();
    /**
     * Display a list of available triggers
     */
    $items = $GLOBALS['dbi']->getTriggers($db, $table);
    echo PMA_RTE_getList('trigger', $items);
    /**
     * Display a link for adding a new trigger,
     * if the user has the necessary privileges
     */
    echo PMA_TRI_getFooterLinks();
} // end PMA_TRI_main()

/**
 * Handles editor requests for adding or editing an item
 *
 * @return void
 */
function PMA_TRI_handleEditor()
{
    global $_REQUEST, $_POST, $errors, $db, $table;

    if (! empty($_REQUEST['editor_process_add'])
        || ! empty($_REQUEST['editor_process_edit'])
    ) {
        $sql_query = '';

        $item_query = PMA_TRI_getQueryFromRequest();

        if (! count($errors)) { // set by PMA_RTN_getQueryFromRequest()
            // Execute the created query
            if (! empty($_REQUEST['editor_process_edit'])) {
                // Backup the old trigger, in case something goes wrong
                $trigger = PMA_TRI_getDataFromName($_REQUEST['item_original_name']);
                $create_item = $trigger['create'];
                $drop_item = $trigger['drop'] . ';';
                $result = $GLOBALS['dbi']->tryQuery($drop_item);
                if (! $result) {
                    $errors[] = sprintf(
                        __('The following query has failed: "%s"'),
                        htmlspecialchars($drop_item)
                    )
                    . '<br />'
                    . __('MySQL said: ') . $GLOBALS['dbi']->getError(null);
                } else {
                    $result = $GLOBALS['dbi']->tryQuery($item_query);
                    if (! $result) {
                        $errors[] = sprintf(
                            __('The following query has failed: "%s"'),
                            htmlspecialchars($item_query)
                        )
                        . '<br />'
                        . __('MySQL said: ') . $GLOBALS['dbi']->getError(null);
                        // We dropped the old item, but were unable to create the
                        // new one. Try to restore the backup query.
                        $result = $GLOBALS['dbi']->tryQuery($create_item);
                        if (! $result) {
                            // OMG, this is really bad! We dropped the query,
                            // failed to create a new one
                            // and now even the backup query does not execute!
                            // This should not happen, but we better handle
                            // this just in case.
                            $errors[] = __(
                                'Sorry, we failed to restore the dropped trigger.'
                            )
                            . '<br />'
                            . __('The backed up query was:')
                            . "\"" . htmlspecialchars($create_item) . "\""
                            . '<br />'
                            . __('MySQL said: ') . $GLOBALS['dbi']->getError(null);
                        }
                    } else {
                        $message = PMA_Message::success(
                            __('Trigger %1$s has been modified.')
                        );
                        $message->addParam(
                            PMA_Util::backquote($_REQUEST['item_name'])
                        );
                        $sql_query = $drop_item . $item_query;
                    }
                }
            } else {
                // 'Add a new item' mode
                $result = $GLOBALS['dbi']->tryQuery($item_query);
                if (! $result) {
                    $errors[] = sprintf(
                        __('The following query has failed: "%s"'),
                        htmlspecialchars($item_query)
                    )
                    . '<br /><br />'
                    . __('MySQL said: ') . $GLOBALS['dbi']->getError(null);
                } else {
                    $message = PMA_Message::success(
                        __('Trigger %1$s has been created.')
                    );
                    $message->addParam(
                        PMA_Util::backquote($_REQUEST['item_name'])
                    );
                    $sql_query = $item_query;
                }
            }
        }

        if (count($errors)) {
            $message = PMA_Message::error(
                '<b>'
                . __(
                    'One or more errors have occurred while processing your request:'
                )
                . '</b>'
            );
            $message->addString('<ul>');
            foreach ($errors as $string) {
                $message->addString('<li>' . $string . '</li>');
            }
            $message->addString('</ul>');
        }

        $output = PMA_Util::getMessage($message, $sql_query);
        if ($GLOBALS['is_ajax_request']) {
            $response = PMA_Response::getInstance();
            if ($message->isSuccess()) {
                $items = $GLOBALS['dbi']->getTriggers($db, $table, '');
                $trigger = false;
                foreach ($items as $value) {
                    if ($value['name'] == $_REQUEST['item_name']) {
                        $trigger = $value;
                    }
                }
                $insert = false;
                if (empty($table)
                    || ($trigger !== false && $table == $trigger['table'])
                ) {
                    $insert = true;
                    $response->addJSON('new_row', PMA_TRI_getRowForList($trigger));
                    $response->addJSON(
                        'name',
                        htmlspecialchars(
                            strtoupper($_REQUEST['item_name'])
                        )
                    );
                }
                $response->addJSON('insert', $insert);
                $response->addJSON('message', $output);
            } else {
                $response->addJSON('message', $message);
                $response->isSuccess(false);
            }
            exit;
        }
    }

    /**
     * Display a form used to add/edit a trigger, if necessary
     */
    if (count($errors)
        || (empty($_REQUEST['editor_process_add'])
        && empty($_REQUEST['editor_process_edit'])
        && (! empty($_REQUEST['add_item'])
        || ! empty($_REQUEST['edit_item']))) // FIXME: this must be simpler than that
    ) {
        // Get the data for the form (if any)
        if (! empty($_REQUEST['add_item'])) {
            $title = PMA_RTE_getWord('add');
            $item = PMA_TRI_getDataFromRequest();
            $mode = 'add';
        } else if (! empty($_REQUEST['edit_item'])) {
            $title = __("Edit trigger");
            if (! empty($_REQUEST['item_name'])
                && empty($_REQUEST['editor_process_edit'])
            ) {
                $item = PMA_TRI_getDataFromName($_REQUEST['item_name']);
                if ($item !== false) {
                    $item['item_original_name'] = $item['item_name'];
                }
            } else {
                $item = PMA_TRI_getDataFromRequest();
            }
            $mode = 'edit';
        }
        if ($item !== false) {
            // Show form
            $editor = PMA_TRI_getEditorForm($mode, $item);
            if ($GLOBALS['is_ajax_request']) {
                $response = PMA_Response::getInstance();
                $response->addJSON('message', $editor);
                $response->addJSON('title', $title);
            } else {
                echo "\n\n<h2>$title</h2>\n\n$editor";
                unset($_POST);
            }
            exit;
        } else {
            $message  = __('Error in processing request:') . ' ';
            $message .= sprintf(
                PMA_RTE_getWord('not_found'),
                htmlspecialchars(PMA_Util::backquote($_REQUEST['item_name'])),
                htmlspecialchars(PMA_Util::backquote($db))
            );
            $message = PMA_message::error($message);
            if ($GLOBALS['is_ajax_request']) {
                $response = PMA_Response::getInstance();
                $response->isSuccess(false);
                $response->addJSON('message', $message);
                exit;
            } else {
                $message->display();
            }
        }
    }
} // end PMA_TRI_handleEditor()

/**
 * This function will generate the values that are required to for the editor
 *
 * @return array    Data necessary to create the editor.
 */
function PMA_TRI_getDataFromRequest()
{
    $retval = array();
    $indices = array('item_name',
                     'item_table',
                     'item_original_name',
                     'item_action_timing',
                     'item_event_manipulation',
                     'item_definition',
                     'item_definer');
    foreach ($indices as $index) {
        $retval[$index] = isset($_REQUEST[$index]) ? $_REQUEST[$index] : '';
    }
    return $retval;
} // end PMA_TRI_getDataFromRequest()

/**
 * This function will generate the values that are required to complete
 * the "Edit trigger" form given the name of a trigger.
 *
 * @param string $name The name of the trigger.
 *
 * @return array Data necessary to create the editor.
 */
function PMA_TRI_getDataFromName($name)
{
    global $db, $table, $_REQUEST;

    $temp = array();
    $items = $GLOBALS['dbi']->getTriggers($db, $table, '');
    foreach ($items as $value) {
        if ($value['name'] == $name) {
            $temp = $value;
        }
    }
    if (empty($temp)) {
        return false;
    } else {
        $retval = array();
        $retval['create']                  = $temp['create'];
        $retval['drop']                    = $temp['drop'];
        $retval['item_name']               = $temp['name'];
        $retval['item_table']              = $temp['table'];
        $retval['item_action_timing']      = $temp['action_timing'];
        $retval['item_event_manipulation'] = $temp['event_manipulation'];
        $retval['item_definition']         = $temp['definition'];
        $retval['item_definer']            = $temp['definer'];
        return $retval;
    }
} // end PMA_TRI_getDataFromName()

/**
 * Displays a form used to add/edit a trigger
 *
 * @param string $mode If the editor will be used edit a trigger
 *                     or add a new one: 'edit' or 'add'.
 * @param array  $item Data for the trigger returned by PMA_TRI_getDataFromRequest()
 *                     or PMA_TRI_getDataFromName()
 *
 * @return string HTML code for the editor.
 */
function PMA_TRI_getEditorForm($mode, $item)
{
    global $db, $table, $event_manipulations, $action_timings;

    // Escape special characters
    $need_escape = array(
                       'item_original_name',
                       'item_name',
                       'item_definition',
                       'item_definer'
                   );
    foreach ($need_escape as $key => $index) {
        $item[$index] = htmlentities($item[$index], ENT_QUOTES, 'UTF-8');
    }
    $original_data = '';
    if ($mode == 'edit') {
        $original_data = "<input name='item_original_name' "
                       . "type='hidden' value='{$item['item_original_name']}'/>\n";
    }
    $query  = "SELECT `TABLE_NAME` FROM `INFORMATION_SCHEMA`.`TABLES` ";
    $query .= "WHERE `TABLE_SCHEMA`='" . PMA_Util::sqlAddSlashes($db) . "' ";
    $query .= "AND `TABLE_TYPE`='BASE TABLE'";
    $tables = $GLOBALS['dbi']->fetchResult($query);

    // Create the output
    $retval  = "";
    $retval .= "<!-- START " . strtoupper($mode) . " TRIGGER FORM -->\n\n";
    $retval .= "<form class='rte_form' action='db_triggers.php' method='post'>\n";
    $retval .= "<input name='{$mode}_item' type='hidden' value='1' />\n";
    $retval .= $original_data;
    $retval .= PMA_URL_getHiddenInputs($db, $table) . "\n";
    $retval .= "<fieldset>\n";
    $retval .= "<legend>" . __('Details') . "</legend>\n";
    $retval .= "<table class='rte_table' style='width: 100%'>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td style='width: 20%;'>" . __('Trigger name') . "</td>\n";
    $retval .= "    <td><input type='text' name='item_name' maxlength='64'\n";
    $retval .= "               value='{$item['item_name']}' /></td>\n";
    $retval .= "</tr>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td>" . __('Table') . "</td>\n";
    $retval .= "    <td>\n";
    $retval .= "        <select name='item_table'>\n";
    foreach ($tables as $key => $value) {
        $selected = "";
        if ($mode == 'add' && $value == $table) {
            $selected = " selected='selected'";
        } else if ($mode == 'edit' && $value == $item['item_table']) {
            $selected = " selected='selected'";
        }
        $retval .= "<option$selected>";
        $retval .= htmlspecialchars($value);
        $retval .= "</option>\n";
    }
    $retval .= "        </select>\n";
    $retval .= "    </td>\n";
    $retval .= "</tr>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td>" . _pgettext('Trigger action time', 'Time') . "</td>\n";
    $retval .= "    <td><select name='item_timing'>\n";
    foreach ($action_timings as $key => $value) {
        $selected = "";
        if (! empty($item['item_action_timing'])
            && $item['item_action_timing'] == $value
        ) {
            $selected = " selected='selected'";
        }
        $retval .= "<option$selected>$value</option>";
    }
    $retval .= "    </select></td>\n";
    $retval .= "</tr>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td>" . __('Event') . "</td>\n";
    $retval .= "    <td><select name='item_event'>\n";
    foreach ($event_manipulations as $key => $value) {
        $selected = "";
        if (! empty($item['item_event_manipulation'])
            && $item['item_event_manipulation'] == $value
        ) {
            $selected = " selected='selected'";
        }
        $retval .= "<option$selected>$value</option>";
    }
    $retval .= "    </select></td>\n";
    $retval .= "</tr>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td>" . __('Definition') . "</td>\n";
    $retval .= "    <td><textarea name='item_definition' rows='15' cols='40'>";
    $retval .= $item['item_definition'];
    $retval .= "</textarea></td>\n";
    $retval .= "</tr>\n";
    $retval .= "<tr>\n";
    $retval .= "    <td>" . __('Definer') . "</td>\n";
    $retval .= "    <td><input type='text' name='item_definer'\n";
    $retval .= "               value='{$item['item_definer']}' /></td>\n";
    $retval .= "</tr>\n";
    $retval .= "</table>\n";
    $retval .= "</fieldset>\n";
    if ($GLOBALS['is_ajax_request']) {
        $retval .= "<input type='hidden' name='editor_process_{$mode}'\n";
        $retval .= "       value='true' />\n";
        $retval .= "<input type='hidden' name='ajax_request' value='true' />\n";
    } else {
        $retval .= "<fieldset class='tblFooters'>\n";
        $retval .= "    <input type='submit' name='editor_process_{$mode}'\n";
        $retval .= "           value='" . __('Go') . "' />\n";
        $retval .= "</fieldset>\n";
    }
    $retval .= "</form>\n\n";
    $retval .= "<!-- END " . strtoupper($mode) . " TRIGGER FORM -->\n\n";

    return $retval;
} // end PMA_TRI_getEditorForm()

/**
 * Composes the query necessary to create a trigger from an HTTP request.
 *
 * @return string  The CREATE TRIGGER query.
 */
function PMA_TRI_getQueryFromRequest()
{
    global $_REQUEST, $db, $errors, $action_timings, $event_manipulations;

    $query = 'CREATE ';
    if (! empty($_REQUEST['item_definer'])) {
        if (strpos($_REQUEST['item_definer'], '@') !== false) {
            $arr = explode('@', $_REQUEST['item_definer']);
            $query .= 'DEFINER=' . PMA_Util::backquote($arr[0]);
            $query .= '@' . PMA_Util::backquote($arr[1]) . ' ';
        } else {
            $errors[] = __('The definer must be in the "username@hostname" format!');
        }
    }
    $query .= 'TRIGGER ';
    if (! empty($_REQUEST['item_name'])) {
        $query .= PMA_Util::backquote($_REQUEST['item_name']) . ' ';
    } else {
        $errors[] = __('You must provide a trigger name!');
    }
    if (! empty($_REQUEST['item_timing'])
        && in_array($_REQUEST['item_timing'], $action_timings)
    ) {
        $query .= $_REQUEST['item_timing'] . ' ';
    } else {
        $errors[] = __('You must provide a valid timing for the trigger!');
    }
    if (! empty($_REQUEST['item_event'])
        && in_array($_REQUEST['item_event'], $event_manipulations)
    ) {
        $query .= $_REQUEST['item_event'] . ' ';
    } else {
        $errors[] = __('You must provide a valid event for the trigger!');
    }
    $query .= 'ON ';
    if (! empty($_REQUEST['item_table'])
        && in_array($_REQUEST['item_table'], $GLOBALS['dbi']->getTables($db))
    ) {
        $query .= PMA_Util::backquote($_REQUEST['item_table']);
    } else {
        $errors[] = __('You must provide a valid table name!');
    }
    $query .= ' FOR EACH ROW ';
    if (! empty($_REQUEST['item_definition'])) {
        $query .= $_REQUEST['item_definition'];
    } else {
        $errors[] = __('You must provide a trigger definition.');
    }

    return $query;
} // end PMA_TRI_getQueryFromRequest()

?>
