/**
* Handle showing/processing the submission from the block editing form.
* @return boolean true if the form was submitted and the new config saved. Does not
* return if the editing form was displayed. False otherwise.
*/
public function process_url_move()
{
global $CFG, $DB, $PAGE;
$blockid = optional_param('bui_moveid', null, PARAM_INT);
if (!$blockid) {
return false;
}
require_sesskey();
$block = $this->find_instance($blockid);
if (!$this->page->user_can_edit_blocks()) {
throw new moodle_exception('nopermissions', '', $this->page->url->out(), get_string('editblock'));
}
$newregion = optional_param('bui_newregion', '', PARAM_ALPHANUMEXT);
$newweight = optional_param('bui_newweight', null, PARAM_FLOAT);
if (!$newregion || is_null($newweight)) {
// Don't have a valid target position yet, must be just starting the move.
$this->movingblock = $blockid;
$this->page->ensure_param_not_in_url('bui_moveid');
return false;
}
if (!$this->is_known_region($newregion)) {
throw new moodle_exception('unknownblockregion', '', $this->page->url, $newregion);
}
// Move this block. This may involve moving other nearby blocks.
$blocks = $this->birecordsbyregion[$newregion];
$maxweight = self::MAX_WEIGHT;
$minweight = -self::MAX_WEIGHT;
// Initialise the used weights and spareweights array with the default values
$spareweights = array();
$usedweights = array();
for ($i = $minweight; $i <= $maxweight; $i++) {
$spareweights[$i] = $i;
$usedweights[$i] = array();
}
// Check each block and sort out where we have used weights
foreach ($blocks as $bi) {
if ($bi->weight > $maxweight) {
// If this statement is true then the blocks weight is more than the
// current maximum. To ensure that we can get the best block position
// we will initialise elements within the usedweights and spareweights
// arrays between the blocks weight (which will then be the new max) and
// the current max
$parseweight = $bi->weight;
while (!array_key_exists($parseweight, $usedweights)) {
$usedweights[$parseweight] = array();
$spareweights[$parseweight] = $parseweight;
$parseweight--;
}
$maxweight = $bi->weight;
} else {
if ($bi->weight < $minweight) {
// As above except this time the blocks weight is LESS than the
// the current minimum, so we will initialise the array from the
// blocks weight (new minimum) to the current minimum
$parseweight = $bi->weight;
while (!array_key_exists($parseweight, $usedweights)) {
$usedweights[$parseweight] = array();
$spareweights[$parseweight] = $parseweight;
$parseweight++;
}
$minweight = $bi->weight;
}
}
if ($bi->id != $block->instance->id) {
unset($spareweights[$bi->weight]);
$usedweights[$bi->weight][] = $bi->id;
}
}
// First we find the nearest gap in the list of weights.
$bestdistance = max(abs($newweight - self::MAX_WEIGHT), abs($newweight + self::MAX_WEIGHT)) + 1;
$bestgap = null;
foreach ($spareweights as $spareweight) {
if (abs($newweight - $spareweight) < $bestdistance) {
$bestdistance = abs($newweight - $spareweight);
$bestgap = $spareweight;
}
}
// If there is no gap, we have to go outside -self::MAX_WEIGHT .. self::MAX_WEIGHT.
if (is_null($bestgap)) {
$bestgap = self::MAX_WEIGHT + 1;
while (!empty($usedweights[$bestgap])) {
$bestgap++;
}
}
// Now we know the gap we are aiming for, so move all the blocks along.
if ($bestgap < $newweight) {
$newweight = floor($newweight);
for ($weight = $bestgap + 1; $weight <= $newweight; $weight++) {
foreach ($usedweights[$weight] as $biid) {
$this->reposition_block($biid, $newregion, $weight - 1);
}
}
$this->reposition_block($block->instance->id, $newregion, $newweight);
} else {
$newweight = ceil($newweight);
for ($weight = $bestgap - 1; $weight >= $newweight; $weight--) {
if (array_key_exists($weight, $usedweights)) {
foreach ($usedweights[$weight] as $biid) {
$this->reposition_block($biid, $newregion, $weight + 1);
}
}
}
$this->reposition_block($block->instance->id, $newregion, $newweight);
}
$this->page->ensure_param_not_in_url('bui_moveid');
$this->page->ensure_param_not_in_url('bui_newregion');
$this->page->ensure_param_not_in_url('bui_newweight');
return true;
}
