<?php
/**
* @package dompdf
* @link http://dompdf.github.com/
* @author Benj Carson <benjcarson@digitaljunkies.ca>
* @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
*/
namespace Dompdf\FrameReflower;
use Dompdf\Dompdf;
use Dompdf\Helpers;
use Dompdf\Frame;
use Dompdf\FrameDecorator\Block;
use Dompdf\Frame\Factory;
/**
* Base reflower class
*
* Reflower objects are responsible for determining the width and height of
* individual frames. They also create line and page breaks as necessary.
*
* @package dompdf
*/
abstract class AbstractFrameReflower
{
/**
* Frame for this reflower
*
* @var Frame
*/
protected $_frame;
/**
* Cached min/max (content) size
*
* @var array
*/
protected $_min_max_cache;
/**
* AbstractFrameReflower constructor.
* @param Frame $frame
*/
function __construct(Frame $frame)
{
$this->_frame = $frame;
$this->_min_max_cache = null;
}
function dispose()
{
}
/**
* @return Dompdf
*/
function get_dompdf()
{
return $this->_frame->get_dompdf();
}
public function reset(): void
{
$this->_min_max_cache = null;
}
/**
* Determine the actual containing block for absolute and fixed position.
*
* https://www.w3.org/TR/CSS21/visudet.html#containing-block-details
*/
protected function determine_absolute_containing_block(): void
{
$frame = $this->_frame;
$style = $frame->get_style();
switch ($style->position) {
case "absolute":
$parent = $frame->find_positionned_parent();
if ($parent !== $frame->get_root()) {
$parent_style = $parent->get_style();
$parent_padding_box = $parent->get_padding_box();
//FIXME: an accurate measure of the positioned parent height
// is not possible until reflow has completed;
// we'll fall back to the parent's containing block,
// which is wrong for auto-height parents
if ($parent_style->height === "auto") {
$parent_containing_block = $parent->get_containing_block();
$containing_block_height = $parent_containing_block["h"] -
(float)$parent_style->length_in_pt([
$parent_style->margin_top,
$parent_style->margin_bottom,
$parent_style->border_top_width,
$parent_style->border_bottom_width
], $parent_containing_block["w"]);
} else {
$containing_block_height = $parent_padding_box["h"];
}
$frame->set_containing_block($parent_padding_box["x"], $parent_padding_box["y"], $parent_padding_box["w"], $containing_block_height);
break;
}
case "fixed":
$initial_cb = $frame->get_root()->get_first_child()->get_containing_block();
$frame->set_containing_block($initial_cb["x"], $initial_cb["y"], $initial_cb["w"], $initial_cb["h"]);
break;
default:
// Nothing to do, containing block already set via parent
break;
}
}
/**
* Collapse frames margins
* http://www.w3.org/TR/CSS21/box.html#collapsing-margins
*/
protected function _collapse_margins()
{
$frame = $this->_frame;
// Margins of float/absolutely positioned/inline-level elements do not collapse
if (!$frame->is_in_flow() || $frame->is_inline_level()
|| $frame->get_root() === $frame || $frame->get_parent() === $frame->get_root()
) {
return;
}
$cb = $frame->get_containing_block();
$style = $frame->get_style();
$t = $style->length_in_pt($style->margin_top, $cb["w"]);
$b = $style->length_in_pt($style->margin_bottom, $cb["w"]);
// Handle 'auto' values
if ($t === "auto") {
$style->margin_top = 0;
$t = 0;
}
if ($b === "auto") {
$style->margin_bottom = 0;
$b = 0;
}
// Collapse vertical margins:
$n = $frame->get_next_sibling();
if ( $n && !($n->is_block_level() && $n->is_in_flow()) ) {
while ($n = $n->get_next_sibling()) {
if ($n->is_block_level() && $n->is_in_flow()) {
break;
}
if (!$n->get_first_child()) {
$n = null;
break;
}
}
}
if ($n) {
$n_style = $n->get_style();
$n_t = (float)$n_style->length_in_pt($n_style->margin_top, $cb["w"]);
$b = $this->_get_collapsed_margin_length($b, $n_t);
$style->margin_bottom = $b;
$n_style->margin_top = 0;
}
// Collapse our first child's margin, if there is no border or padding
if ($style->border_top_width == 0 && $style->length_in_pt($style->padding_top) == 0) {
$f = $this->_frame->get_first_child();
if ( $f && !($f->is_block_level() && $f->is_in_flow()) ) {
while ($f = $f->get_next_sibling()) {
if ($f->is_block_level() && $f->is_in_flow()) {
break;
}
if (!$f->get_first_child()) {
$f = null;
break;
}
}
}
// Margins are collapsed only between block-level boxes
if ($f) {
$f_style = $f->get_style();
$f_t = (float)$f_style->length_in_pt($f_style->margin_top, $cb["w"]);
$t = $this->_get_collapsed_margin_length($t, $f_t);
$style->margin_top = $t;
$f_style->margin_top = 0;
}
}
// Collapse our last child's margin, if there is no border or padding
if ($style->border_bottom_width == 0 && $style->length_in_pt($style->padding_bottom) == 0) {
$l = $this->_frame->get_last_child();
if ( $l && !($l->is_block_level() && $l->is_in_flow()) ) {
while ($l = $l->get_prev_sibling()) {
if ($l->is_block_level() && $l->is_in_flow()) {
break;
}
if (!$l->get_last_child()) {
$l = null;
break;
}
}
}
// Margins are collapsed only between block-level boxes
if ($l) {
$l_style = $l->get_style();
$l_b = (float)$l_style->length_in_pt($l_style->margin_bottom, $cb["w"]);
$b = $this->_get_collapsed_margin_length($b, $l_b);
$style->margin_bottom = $b;
$l_style->margin_bottom = 0;
}
}
}
/**
* Get the combined (collapsed) length of two adjoining margins.
*
* See http://www.w3.org/TR/CSS21/box.html#collapsing-margins.
*
* @param float $length1
* @param float $length2
* @return float
*/
private function _get_collapsed_margin_length($length1, $length2)
{
if ($length1 < 0 && $length2 < 0) {
return min($length1, $length2); // min(x, y) = - max(abs(x), abs(y)), if x < 0 && y < 0
}
if ($length1 < 0 || $length2 < 0) {
return $length1 + $length2; // x + y = x - abs(y), if y < 0
}
return max($length1, $length2);
}
/**
* Handle relative positioning according to
* https://www.w3.org/TR/CSS21/visuren.html#relative-positioning.
*
* @param Frame $frame The frame to handle.
*/
protected function position_relative(Frame $frame): void
{
$style = $frame->get_style();
if ($style->position === "relative") {
$cb = $frame->get_containing_block();
$top = $style->length_in_pt($style->top, $cb["h"]);
$right = $style->length_in_pt($style->right, $cb["w"]);
$bottom = $style->length_in_pt($style->bottom, $cb["h"]);
$left = $style->length_in_pt($style->left, $cb["w"]);
// FIXME RTL case:
// if ($left !== "auto" && $right !== "auto") $left = -$right;
if ($left === "auto" && $right === "auto") {
$left = 0;
} elseif ($left === "auto") {
$left = -(float) $right;
}
if ($top === "auto" && $bottom === "auto") {
$top = 0;
} elseif ($top === "auto") {
$top = -(float) $bottom;
}
$frame->move((float) $left, (float) $top);
}
}
/**
* @param Block|null $block
* @return mixed
*/
abstract function reflow(Block $block = null);
/**
* Get the minimum and maximum width of the content of this frame.
*
* @return array An array [0 => min, 1 => max, "min" => min, "max" => max]
* of the min and max width.
*/
function get_min_max_content_width(): array
{
if (!is_null($this->_min_max_cache)) {
return $this->_min_max_cache;
}
$cb_w = $this->_frame->get_containing_block("w");
$style = $this->_frame->get_style();
// Ignore percentage values for a specified width here, as the
// containing block is not defined yet
$display = $style->display;
$width = $style->width;
$fixed_width = $width !== "auto" && !Helpers::is_percent($width);
// If the frame has a specified width, then we don't need to check its
// children. Table cells are handled slightly differently below
if ($fixed_width && $display !== "inline" && $display !== "table-cell") {
$width = (float) $style->length_in_pt($width, $cb_w);
return $this->_min_max_cache = [$width, $width, "min" => $width, "max" => $width];
}
$low = [];
$high = [];
for ($iter = $this->_frame->get_children()->getIterator(); $iter->valid(); $iter->next()) {
$inline_min = 0;
$inline_max = 0;
// Add all adjacent inline widths together to calculate max width
while ($iter->valid() && ($iter->current()->is_inline_level() || $iter->current()->get_style()->display === "-dompdf-image")) {
$child = $iter->current();
$child->get_reflower()->_set_content();
$minmax = $child->get_min_max_width();
if (in_array($child->get_style()->white_space, ["pre", "nowrap"], true)) {
$inline_min += $minmax["min"];
} else {
$low[] = $minmax["min"];
}
$inline_max += $minmax["max"];
$iter->next();
}
if ($inline_min > 0) {
$low[] = $inline_min;
}
if ($inline_max > 0) {
$high[] = $inline_max;
}
// Skip children with absolute position
if ($iter->valid() && !$iter->current()->is_absolute()) {
$child = $iter->current();
$child->get_reflower()->_set_content();
list($low[], $high[]) = $child->get_min_max_width();
}
}
$min = count($low) ? max($low) : 0;
$max = count($high) ? max($high) : 0;
// For table cells: Use specified width if it is greater than the
// minimum defined by the content
if ($fixed_width && $display === "table-cell") {
$width = (float) $style->length_in_pt($width, $cb_w);
$min = max($width, $min);
$max = $min;
}
return $this->_min_max_cache = [$min, $max, "min" => $min, "max" => $max];
}
/**
* Required for table layout: Get the minimum and maximum width of this
* frame. This provides a basic implementation. Child classes should
* override this if necessary.
*
* @return array An array [0 => min, 1 => max, "min" => min, "max" => max]
* of the min and max width.
*/
function get_min_max_width(): array
{
$style = $this->_frame->get_style();
// Account for margins & padding
$dims = [$style->padding_left,
$style->padding_right,
$style->border_left_width,
$style->border_right_width,
$style->margin_left,
$style->margin_right];
$cb_w = $this->_frame->get_containing_block("w");
$delta = (float)$style->length_in_pt($dims, $cb_w);
[$min, $max] = $this->get_min_max_content_width();
$min += $delta;
$max += $delta;
return [$min, $max, "min" => $min, "max" => $max];
}
/**
* Parses a CSS string containing quotes and escaped hex characters
*
* @param $string string The CSS string to parse
* @param $single_trim
* @return string
*/
protected function _parse_string($string, $single_trim = false)
{
if ($single_trim) {
$string = preg_replace('/^[\"\']/', "", $string);
$string = preg_replace('/[\"\']$/', "", $string);
} else {
$string = trim($string, "'\"");
}
$string = str_replace(["\\\n", '\\"', "\\'"],
["", '"', "'"], $string);
// Convert escaped hex characters into ascii characters (e.g. \A => newline)
$string = preg_replace_callback("/\\\\([0-9a-fA-F]{0,6})/",
function ($matches) { return \Dompdf\Helpers::unichr(hexdec($matches[1])); },
$string);
return $string;
}
/**
* Parses a CSS "quotes" property
*
* @return array|null An array of pairs of quotes
*/
protected function _parse_quotes()
{
// Matches quote types
$re = '/(\'[^\']*\')|(\"[^\"]*\")/';
$quotes = $this->_frame->get_style()->quotes;
// split on spaces, except within quotes
if (!preg_match_all($re, "$quotes", $matches, PREG_SET_ORDER)) {
return null;
}
$quotes_array = [];
foreach ($matches as $_quote) {
$quotes_array[] = $this->_parse_string($_quote[0], true);
}
if (empty($quotes_array)) {
$quotes_array = ['"', '"'];
}
return array_chunk($quotes_array, 2);
}
/**
* Parses the CSS "content" property
*
* @return string|null The resulting string
*/
protected function _parse_content()
{
// Matches generated content
$re = "/\n" .
"\s(counters?\\([^)]*\\))|\n" .
"\A(counters?\\([^)]*\\))|\n" .
"\s([\"']) ( (?:[^\"']|\\\\[\"'])+ )(?<!\\\\)\\3|\n" .
"\A([\"']) ( (?:[^\"']|\\\\[\"'])+ )(?<!\\\\)\\5|\n" .
"\s([^\s\"']+)|\n" .
"\A([^\s\"']+)\n" .
"/xi";
$content = $this->_frame->get_style()->content;
$quotes = $this->_parse_quotes();
// split on spaces, except within quotes
if (!preg_match_all($re, $content, $matches, PREG_SET_ORDER)) {
return null;
}
$text = "";
foreach ($matches as $match) {
if (isset($match[2]) && $match[2] !== "") {
$match[1] = $match[2];
}
if (isset($match[6]) && $match[6] !== "") {
$match[4] = $match[6];
}
if (isset($match[8]) && $match[8] !== "") {
$match[7] = $match[8];
}
if (isset($match[1]) && $match[1] !== "") {
// counters?(...)
$match[1] = mb_strtolower(trim($match[1]));
// Handle counter() references:
// http://www.w3.org/TR/CSS21/generate.html#content
$i = mb_strpos($match[1], ")");
if ($i === false) {
continue;
}
preg_match('/(counters?)(^\()*?\(\s*([^\s,]+)\s*(,\s*["\']?([^"\'\)]*)["\']?\s*(,\s*([^\s)]+)\s*)?)?\)/i', $match[1], $args);
$counter_id = $args[3];
if (strtolower($args[1]) == 'counter') {
// counter(name [,style])
if (isset($args[5])) {
$type = trim($args[5]);
} else {
$type = null;
}
$p = $this->_frame->lookup_counter_frame($counter_id);
$text .= $p->counter_value($counter_id, $type);
} else if (strtolower($args[1]) == 'counters') {
// counters(name, string [,style])
if (isset($args[5])) {
$string = $this->_parse_string($args[5]);
} else {
$string = "";
}
if (isset($args[7])) {
$type = trim($args[7]);
} else {
$type = null;
}
$p = $this->_frame->lookup_counter_frame($counter_id);
$tmp = [];
while ($p) {
// We only want to use the counter values when they actually increment the counter
if (array_key_exists($counter_id, $p->_counters)) {
array_unshift($tmp, $p->counter_value($counter_id, $type));
}
$p = $p->lookup_counter_frame($counter_id);
}
$text .= implode($string, $tmp);
} else {
// countertops?
continue;
}
} else if (isset($match[4]) && $match[4] !== "") {
// String match
$text .= $this->_parse_string($match[4]);
} else if (isset($match[7]) && $match[7] !== "") {
// Directive match
if ($match[7] === "open-quote") {
// FIXME: do something here
$text .= $quotes[0][0];
} else if ($match[7] === "close-quote") {
// FIXME: do something else here
$text .= $quotes[0][1];
} else if ($match[7] === "no-open-quote") {
// FIXME:
} else if ($match[7] === "no-close-quote") {
// FIXME:
} else if (mb_strpos($match[7], "attr(") === 0) {
$i = mb_strpos($match[7], ")");
if ($i === false) {
continue;
}
$attr = mb_substr($match[7], 5, $i - 5);
if ($attr == "") {
continue;
}
$text .= $this->_frame->get_parent()->get_node()->getAttribute($attr);
} else {
continue;
}
}
}
return $text;
}
/**
* Sets the generated content of a generated frame
*/
protected function _set_content()
{
$frame = $this->_frame;
if ($frame->content_set) {
return;
}
$style = $frame->get_style();
if ($style->counter_reset && ($reset = $style->counter_reset) !== "none") {
$vars = preg_split('/\s+/', trim($reset), 2);
$frame->reset_counter($vars[0], isset($vars[1]) ? $vars[1] : 0);
}
if ($style->counter_increment && ($increment = $style->counter_increment) !== "none") {
$frame->increment_counters($increment);
}
if ($style->content && $frame->get_node()->nodeName === "dompdf_generated") {
$content = $this->_parse_content();
$node = $frame->get_node()->ownerDocument->createTextNode($content);
$new_style = $style->get_stylesheet()->create_style();
$new_style->inherit($style);
$new_frame = new Frame($node);
$new_frame->set_style($new_style);
Factory::decorate_frame($new_frame, $frame->get_dompdf(), $frame->get_root());
$frame->append_child($new_frame);
}
$frame->content_set = true;
}
}