function __construct(Frame $frame, Dompdf $dompdf)
{
if (!$frame->is_text_node()) {
throw new Exception("Text_Decorator can only be applied to #text nodes.");
}
parent::__construct($frame, $dompdf);
$this->_text_spacing = null;
}
/**
* Decorate a Frame
*
* @param Frame $frame The frame to decorate
* @param Dompdf $dompdf The dompdf instance
* @param Frame $root The frame to decorate
*
* @throws Exception
* @return AbstractFrameDecorator
* FIXME: this is admittedly a little smelly...
*/
static function decorate_frame(Frame $frame, Dompdf $dompdf, Frame $root = null)
{
if (is_null($dompdf)) {
throw new Exception("The DOMPDF argument is required");
}
$style = $frame->get_style();
// Floating (and more generally out-of-flow) elements are blocks
// http://coding.smashingmagazine.com/2007/05/01/css-float-theory-things-you-should-know/
if (!$frame->is_in_flow() && in_array($style->display, Style::$INLINE_TYPES)) {
$style->display = "block";
}
$display = $style->display;
switch ($display) {
case "block":
$positioner = "Block";
$decorator = "Block";
$reflower = "Block";
break;
case "inline-block":
$positioner = "Inline";
$decorator = "Block";
$reflower = "Block";
break;
case "inline":
$positioner = "Inline";
if ($frame->is_text_node()) {
$decorator = "Text";
$reflower = "Text";
} else {
$enable_css_float = $dompdf->get_option("enable_css_float");
if ($enable_css_float && $style->float !== "none") {
$decorator = "Block";
$reflower = "Block";
} else {
$decorator = "Inline";
$reflower = "Inline";
}
}
break;
case "table":
$positioner = "Block";
$decorator = "Table";
$reflower = "Table";
break;
case "inline-table":
$positioner = "Inline";
$decorator = "Table";
$reflower = "Table";
break;
case "table-row-group":
case "table-header-group":
case "table-footer-group":
$positioner = "Null";
$decorator = "TableRowGroup";
$reflower = "TableRowGroup";
break;
case "table-row":
$positioner = "Null";
$decorator = "TableRow";
$reflower = "TableRow";
break;
case "table-cell":
$positioner = "TableCell";
$decorator = "TableCell";
$reflower = "TableCell";
break;
case "list-item":
$positioner = "Block";
$decorator = "Block";
$reflower = "Block";
break;
case "-dompdf-list-bullet":
if ($style->list_style_position === "inside") {
$positioner = "Inline";
} else {
$positioner = "ListBullet";
}
if ($style->list_style_image !== "none") {
$decorator = "ListBulletImage";
} else {
$decorator = "ListBullet";
}
$reflower = "ListBullet";
break;
case "-dompdf-image":
$positioner = "Inline";
$decorator = "Image";
$reflower = "Image";
break;
case "-dompdf-br":
$positioner = "Inline";
$decorator = "Inline";
$reflower = "Inline";
break;
default:
// FIXME: should throw some sort of warning or something?
// FIXME: should throw some sort of warning or something?
case "none":
if ($style->_dompdf_keep !== "yes") {
// Remove the node and the frame
$frame->get_parent()->remove_child($frame);
return;
}
$positioner = "Null";
$decorator = "Null";
$reflower = "Null";
break;
}
// Handle CSS position
$position = $style->position;
if ($position === "absolute") {
$positioner = "Absolute";
} else {
if ($position === "fixed") {
$positioner = "Fixed";
}
}
$node = $frame->get_node();
// Handle nodeName
if ($node->nodeName === "img") {
$style->display = "-dompdf-image";
$decorator = "Image";
$reflower = "Image";
}
$positioner = "Dompdf\\Positioner\\{$positioner}";
$decorator = "Dompdf\\FrameDecorator\\{$decorator}";
$reflower = "Dompdf\\FrameReflower\\{$reflower}";
/** @var AbstractFrameDecorator $deco */
$deco = new $decorator($frame, $dompdf);
$deco->set_positioner(new $positioner($deco));
$deco->set_reflower(new $reflower($deco, $dompdf->getFontMetrics()));
if ($root) {
$deco->set_root($root);
}
if ($display === "list-item") {
// Insert a list-bullet frame
$xml = $dompdf->get_dom();
$bullet_node = $xml->createElement("bullet");
// arbitrary choice
$b_f = new Frame($bullet_node);
$node = $frame->get_node();
$parent_node = $node->parentNode;
if ($parent_node) {
if (!$parent_node->hasAttribute("dompdf-children-count")) {
$xpath = new DOMXPath($xml);
$count = $xpath->query("li", $parent_node)->length;
$parent_node->setAttribute("dompdf-children-count", $count);
}
if (is_numeric($node->getAttribute("value"))) {
$index = intval($node->getAttribute("value"));
} else {
if (!$parent_node->hasAttribute("dompdf-counter")) {
$index = $parent_node->hasAttribute("start") ? $parent_node->getAttribute("start") : 1;
} else {
$index = $parent_node->getAttribute("dompdf-counter") + 1;
}
}
$parent_node->setAttribute("dompdf-counter", $index);
$bullet_node->setAttribute("dompdf-counter", $index);
}
$new_style = $dompdf->get_css()->create_style();
$new_style->display = "-dompdf-list-bullet";
$new_style->inherit($style);
$b_f->set_style($new_style);
$deco->prepend_child(Factory::decorate_frame($b_f, $dompdf, $root));
}
return $deco;
}
/**
* Determine if a page break is allowed before $frame
* http://www.w3.org/TR/CSS21/page.html#allowed-page-breaks
*
* In the normal flow, page breaks can occur at the following places:
*
* 1. In the vertical margin between block boxes. When a page
* break occurs here, the used values of the relevant
* 'margin-top' and 'margin-bottom' properties are set to '0'.
* 2. Between line boxes inside a block box.
*
* These breaks are subject to the following rules:
*
* * Rule A: Breaking at (1) is allowed only if the
* 'page-break-after' and 'page-break-before' properties of
* all the elements generating boxes that meet at this margin
* allow it, which is when at least one of them has the value
* 'always', 'left', or 'right', or when all of them are
* 'auto'.
*
* * Rule B: However, if all of them are 'auto' and the
* nearest common ancestor of all the elements has a
* 'page-break-inside' value of 'avoid', then breaking here is
* not allowed.
*
* * Rule C: Breaking at (2) is allowed only if the number of
* line boxes between the break and the start of the enclosing
* block box is the value of 'orphans' or more, and the number
* of line boxes between the break and the end of the box is
* the value of 'widows' or more.
*
* * Rule D: In addition, breaking at (2) is allowed only if
* the 'page-break-inside' property is 'auto'.
*
* If the above doesn't provide enough break points to keep
* content from overflowing the page boxes, then rules B and D are
* dropped in order to find additional breakpoints.
*
* If that still does not lead to sufficient break points, rules A
* and C are dropped as well, to find still more break points.
*
* We will also allow breaks between table rows. However, when
* splitting a table, the table headers should carry over to the
* next page (but they don't yet).
*
* @param Frame $frame the frame to check
*
* @return bool true if a break is allowed, false otherwise
*/
protected function _page_break_allowed(Frame $frame)
{
$block_types = array("block", "list-item", "table", "-dompdf-image");
Helpers::dompdf_debug("page-break", "_page_break_allowed(" . $frame->get_node()->nodeName . ")");
$display = $frame->get_style()->display;
// Block Frames (1):
if (in_array($display, $block_types)) {
// Avoid breaks within table-cells
if ($this->_in_table) {
Helpers::dompdf_debug("page-break", "In table: " . $this->_in_table);
return false;
}
// Rules A & B
if ($frame->get_style()->page_break_before === "avoid") {
Helpers::dompdf_debug("page-break", "before: avoid");
return false;
}
// Find the preceeding block-level sibling
$prev = $frame->get_prev_sibling();
while ($prev && !in_array($prev->get_style()->display, $block_types)) {
$prev = $prev->get_prev_sibling();
}
// Does the previous element allow a page break after?
if ($prev && $prev->get_style()->page_break_after === "avoid") {
Helpers::dompdf_debug("page-break", "after: avoid");
return false;
}
// If both $prev & $frame have the same parent, check the parent's
// page_break_inside property.
$parent = $frame->get_parent();
if ($prev && $parent && $parent->get_style()->page_break_inside === "avoid") {
Helpers::dompdf_debug("page-break", "parent inside: avoid");
return false;
}
// To prevent cascading page breaks when a top-level element has
// page-break-inside: avoid, ensure that at least one frame is
// on the page before splitting.
if ($parent->get_node()->nodeName === "body" && !$prev) {
// We are the body's first child
Helpers::dompdf_debug("page-break", "Body's first child.");
return false;
}
// If the frame is the first block-level frame, use the value from
// $frame's parent instead.
if (!$prev && $parent) {
return $this->_page_break_allowed($parent);
}
Helpers::dompdf_debug("page-break", "block: break allowed");
return true;
} else {
if (in_array($display, Style::$INLINE_TYPES)) {
// Avoid breaks within table-cells
if ($this->_in_table) {
Helpers::dompdf_debug("page-break", "In table: " . $this->_in_table);
return false;
}
// Rule C
$block_parent = $frame->find_block_parent();
if (count($block_parent->get_line_boxes()) < $frame->get_style()->orphans) {
Helpers::dompdf_debug("page-break", "orphans");
return false;
}
// FIXME: Checking widows is tricky without having laid out the
// remaining line boxes. Just ignore it for now...
// Rule D
$p = $block_parent;
while ($p) {
if ($p->get_style()->page_break_inside === "avoid") {
Helpers::dompdf_debug("page-break", "parent->inside: avoid");
return false;
}
$p = $p->find_block_parent();
}
// To prevent cascading page breaks when a top-level element has
// page-break-inside: avoid, ensure that at least one frame with
// some content is on the page before splitting.
$prev = $frame->get_prev_sibling();
while ($prev && ($prev->is_text_node() && trim($prev->get_node()->nodeValue) == "")) {
$prev = $prev->get_prev_sibling();
}
if ($block_parent->get_node()->nodeName === "body" && !$prev) {
// We are the body's first child
Helpers::dompdf_debug("page-break", "Body's first child.");
return false;
}
// Skip breaks on empty text nodes
if ($frame->is_text_node() && $frame->get_node()->nodeValue == "") {
return false;
}
Helpers::dompdf_debug("page-break", "inline: break allowed");
return true;
// Table-rows
} else {
if ($display === "table-row") {
// Simply check if the parent table's page_break_inside property is
// not 'avoid'
$p = Table::find_parent_table($frame);
while ($p) {
if ($p->get_style()->page_break_inside === "avoid") {
Helpers::dompdf_debug("page-break", "parent->inside: avoid");
return false;
}
$p = $p->find_block_parent();
}
// Avoid breaking after the first row of a table
if ($p && $p->get_first_child() === $frame) {
Helpers::dompdf_debug("page-break", "table: first-row");
return false;
}
// If this is a nested table, prevent the page from breaking
if ($this->_in_table > 1) {
Helpers::dompdf_debug("page-break", "table: nested table");
return false;
}
Helpers::dompdf_debug("page-break", "table-row/row-groups: break allowed");
return true;
} else {
if (in_array($display, Table::$ROW_GROUPS)) {
// Disallow breaks at row-groups: only split at row boundaries
return false;
} else {
Helpers::dompdf_debug("page-break", "? " . $frame->get_style()->display . "");
return false;
}
}
}
}
}
