Source of file Page.php
Size: 21,422 Bytes - Last Modified: 2021-12-23T10:11:59+00:00
/var/www/docs.ssmods.com/process/src/ext/dompdf/dompdf/src/FrameDecorator/Page.php
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Overridden to set $this->_bottom_page_margin. * * @param float $x * @param float $y * @param float $w * @param float $h */ function set_containing_block($x = null, $y = null, $w = null, $h = null) { parent::set_containing_block($x, $y, $w, $h); //$w = $this->get_containing_block("w"); if (isset($h)) { $this->_bottom_page_margin = $h; } // - $this->_frame->get_style()->length_in_pt($this->_frame->get_style()->margin_bottom, $w); } /** * Returns true if the page is full and is no longer accepting frames. * * @return bool */ function is_full() { return $this->_page_full; } /** * Start a new page by resetting the full flag. */ function next_page() { $this->_floating_frames = array(); $this->_renderer->new_page(); $this->_page_full = false; } /** * Indicate to the page that a table is currently being reflowed. */ function table_reflow_start() { $this->_in_table++; } /** * Indicate to the page that table reflow is finished. */ function table_reflow_end() { $this->_in_table--; } /** * Return whether we are currently in a nested table or not * * @return bool */ function in_nested_table() { return $this->_in_table > 1; } /** * Check if a forced page break is required before $frame. This uses the * frame's page_break_before property as well as the preceeding frame's * page_break_after property. * * @link http://www.w3.org/TR/CSS21/page.html#forced * * @param Frame $frame the frame to check * * @return bool true if a page break occured */ function check_forced_page_break(Frame $frame) { // Skip check if page is already split if ($this->_page_full) { return null; } $block_types = array("block", "list-item", "table", "inline"); $page_breaks = array("always", "left", "right"); $style = $frame->get_style(); if (!in_array($style->display, $block_types)) { return false; } // Find the previous block-level sibling $prev = $frame->get_prev_sibling(); while ($prev && !in_array($prev->get_style()->display, $block_types)) { $prev = $prev->get_prev_sibling(); } if (in_array($style->page_break_before, $page_breaks)) { // Prevent cascading splits $frame->split(null, true); // We have to grab the style again here because split() resets // $frame->style to the frame's orignal style. $frame->get_style()->page_break_before = "auto"; $this->_page_full = true; return true; } if ($prev && in_array($prev->get_style()->page_break_after, $page_breaks)) { // Prevent cascading splits $frame->split(null, true); $prev->get_style()->page_break_after = "auto"; $this->_page_full = true; return true; } if ($prev && $prev->get_last_child() && $frame->get_node()->nodeName != "body") { $prev_last_child = $prev->get_last_child(); if (in_array($prev_last_child->get_style()->page_break_after, $page_breaks)) { $frame->split(null, true); $prev_last_child->get_style()->page_break_after = "auto"; $this->_page_full = true; return true; } } return false; } /** * 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; } // Inline frames (2): 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' $table = Table::find_parent_table($frame); $p = $table; while ($p) { if ($p->get_style()->page_break_inside === "avoid") { Helpers::dompdf_debug("page-break", "parent->inside: avoid"); return false; } $p = $p->find_block_parent(); } // Avoid breaking after the first row of a table if ($table && $table->get_first_child() === $frame || $table->get_first_child()->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; } } } } } /** * Check if $frame will fit on the page. If the frame does not fit, * the frame tree is modified so that a page break occurs in the * correct location. * * @param Frame $frame the frame to check * * @return bool */ function check_page_break(Frame $frame) { //FIXME: should not need to do this since we're tracking table status in `$this->_in_table` $p = $frame; $in_table = false; while ($p) { if ($p->is_table()) { $in_table = true; break; } $p = $p->get_parent(); } // Do not split if we have already or if the frame was already // pushed to the next page (prevents infinite loops) if ($in_table) { if ($this->_page_full && $frame->_already_pushed) { return false; } } elseif ($this->_page_full || $frame->_already_pushed) { return false; } //FIXME: work-around for infinite loop due to tables if ($in_table && $frame->_already_pushed) { return false; } $p = $frame; do { $display = $p->get_style()->display; if ($display == "table-row") { if ($p->_already_pushed) { return false; } } } while ($p = $p->get_parent()); // If the frame is absolute of fixed it shouldn't break $p = $frame; do { if ($p->is_absolute()) { return false; } // FIXME If the row is taller than the page and // if it the first of the page, we don't break $display = $p->get_style()->display; if ($display === "table-row" && !$p->get_prev_sibling() && $p->get_margin_height() > $this->get_margin_height() ) { return false; } } while ($p = $p->get_parent()); $margin_height = $frame->get_margin_height(); // Determine the frame's maximum y value $max_y = (float)$frame->get_position("y") + $margin_height; // If a split is to occur here, then the bottom margins & paddings of all // parents of $frame must fit on the page as well: $p = $frame->get_parent(); while ($p) { $max_y += $p->get_style()->computed_bottom_spacing(); $p = $p->get_parent(); } // Check if $frame flows off the page if ($max_y <= $this->_bottom_page_margin) { // no: do nothing return false; } Helpers::dompdf_debug("page-break", "check_page_break"); Helpers::dompdf_debug("page-break", "in_table: " . $this->_in_table); // yes: determine page break location $iter = $frame; $flg = false; $in_table = $this->_in_table; Helpers::dompdf_debug("page-break", "Starting search"); while ($iter) { // echo "\nbacktrack: " .$iter->get_node()->nodeName ." ".spl_object_hash($iter->get_node()). ""; if ($iter === $this) { Helpers::dompdf_debug("page-break", "reached root."); // We've reached the root in our search. Just split at $frame. break; } if ($this->_page_break_allowed($iter)) { Helpers::dompdf_debug("page-break", "break allowed, splitting."); $iter->split(null, true); $this->_page_full = true; $this->_in_table = $in_table; $frame->_already_pushed = true; return true; } if (!$flg && $next = $iter->get_last_child()) { Helpers::dompdf_debug("page-break", "following last child."); if ($next->is_table()) { $this->_in_table++; } $iter = $next; continue; } if ($next = $iter->get_prev_sibling()) { Helpers::dompdf_debug("page-break", "following prev sibling."); if ($next->is_table() && !$iter->is_table()) { $this->_in_table++; } else if (!$next->is_table() && $iter->is_table()) { $this->_in_table--; } $iter = $next; $flg = false; continue; } if ($next = $iter->get_parent()) { Helpers::dompdf_debug("page-break", "following parent."); if ($iter->is_table()) { $this->_in_table--; } $iter = $next; $flg = true; continue; } break; } $this->_in_table = $in_table; // No valid page break found. Just break at $frame. Helpers::dompdf_debug("page-break", "no valid break found, just splitting."); // If we are in a table, backtrack to the nearest top-level table row if ($this->_in_table) { $iter = $frame; while ($iter && $iter->get_style()->display !== "table-row" && $iter->get_style()->display !== 'table-row-group' && $iter->_already_pushed === false) { $iter = $iter->get_parent(); } if ($iter) { $iter->split(null, true); } else { return false; } } else { $frame->split(null, true); } $this->_page_full = true; $frame->_already_pushed = true; return true; } //........................................................................ /** * @param Frame|null $frame * @param bool $force_pagebreak */ function split(Frame $frame = null, $force_pagebreak = false) { // Do nothing } /** * Add a floating frame * * @param Frame $frame * * @return void */ function add_floating_frame(Frame $frame) { array_unshift($this->_floating_frames, $frame); } /** * @return Frame[] */ function get_floating_frames() { return $this->_floating_frames; } /** * @param $key */ public function remove_floating_frame($key) { unset($this->_floating_frames[$key]); } /** * @param Frame $child * @return int|mixed */ public function get_lowest_float_offset(Frame $child) { $style = $child->get_style(); $side = $style->clear; $float = $style->float; $y = 0; if ($float === "none") { foreach ($this->_floating_frames as $key => $frame) { if ($side === "both" || $frame->get_style()->float === $side) { $y = max($y, $frame->get_position("y") + $frame->get_margin_height()); } $this->remove_floating_frame($key); } } if ($y > 0) { $y++; // add 1px buffer from float } return $y; } } |