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luos/thirdparty/html2ps_pdf/strategy.table.layout.auto.php
Paula Quispe 9eb7d6cac2 HOR-2689
2017-08-03 17:00:30 -04:00

252 lines
10 KiB
PHP

<?php
class StrategyTableLayoutAuto {
function StrategyTableLayoutAuto() {
}
function apply($table, &$context) {
$width = $table->get_width();
return $this->table_columns_fit($table, $width, $context);
}
function use_colspans(&$table, $widths, &$context, $width_fun, $minwc, $maxwc) {
$colspans = $table->get_colspans();
foreach ($colspans as $colspan) {
$cell = $table->content[$colspan->row]->content[$colspan->column];
// apply colspans to the corresponsing colspanned-cell dimension
//
$cell_width = $cell->$width_fun($context);
// now select the pre-calculated widths of columns covered by this cell
// select the list of resizable columns covered by this cell
$spanned_widths = array();
$spanned_resizable = array();
for ($i=$colspan->column; $i < $colspan->column+$colspan->size; $i++) {
$spanned_widths[] = $widths[$i];
$spanned_resizable[] = ($minwc[$i] != $maxwc[$i]);
}
// Sometimes we may encounter the colspan over the empty columns (I mean ALL columns are empty); in this case
// we need to make these columns reizable in order to fit colspanned cell contents
//
if (array_sum($spanned_widths) == 0) {
for ($i=0; $i<count($spanned_widths); $i++) {
$spanned_widths[$i] = EPSILON;
$spanned_resizable[$i] = true;
};
};
// The same problem may arise when all colspanned columns are not resizable; in this case we'll force all
// of them to be resized
$any_resizable = false;
for ($i=0; $i<count($spanned_widths); $i++) {
$any_resizable |= $spanned_resizable[$i];
};
if (!$any_resizable) {
for ($i=0; $i<count($spanned_widths); $i++) {
$spanned_resizable[$i] = true;
};
}
// Expand resizable columns
//
$spanned_widths = expand_to_with_flags($cell_width,$spanned_widths,$spanned_resizable);
// Store modified widths
array_splice($widths, $colspan->column, $colspan->size, $spanned_widths);
};
return $widths;
}
/**
* Fit table columns to the given width
*/
function table_columns_fit(&$table, $width, &$context) {
$minw = $table->get_table_columns_min_widths($context);
$maxw = $table->get_table_columns_max_widths($context);
$minw = $this->use_colspans($table, $minw, $context, 'get_min_width', $minw, $maxw);
$maxw = $this->use_colspans($table, $maxw, $context, 'get_max_width', $minw, $maxw);
// Store number of columns
$columns = count($minw);
// Apply column width constraints
$minwc = array();
$maxwc = array();
$cellpadding = $table->getCSSProperty(CSS_HTML2PS_CELLPADDING);
$cellspacing = $table->getCSSProperty(CSS_HTML2PS_CELLSPACING);
for ($i=0; $i<count($minw); $i++) {
$cwc = $table->get_cwc($i);
// Do not allow constrained max width be less than min width
// Do not allow constrained min width be less than min width
//
$table_width = $table->get_width();
$extra = 2*$cellpadding->getPoints() + $cellspacing->getPoints();
$minwc[$i] = max($minw[$i], $cwc->apply($minw[$i]-$extra, $table_width) + $extra);
$maxwc[$i] = max($minw[$i], $cwc->apply($maxw[$i]-$extra, $table_width) + $extra);
};
$minwc = $table->normalize_min_widths($width, $minw, $minwc);
$minwc = $table->_table_apply_colspans($minwc, $context, 'get_min_width', $minwc, $maxwc);
// We need to normalize widths for the case of colspans width is too big; for example:
// <table><tr><td width="100">
// <table><tr><td width="150">TEXT<td>TEXT<tr><td colspan="2" width="200">
// in this case table SHOULD NOT be expanded over the 100px!
//
// $minwc = $table->normalize_min_widths($width, $minw, $minwc);
$maxwc = $table->_table_apply_colspans($maxwc, $context, 'get_max_width', $minwc, $maxwc);
// Calculate actual widths
$widths = array();
// Calculate widths for all constrained columns
for ($i=0; $i < $columns; $i++) {
if ($table->is_constrained_column($i)) {
$widths[$i] = $minwc[$i];
}
}
// Quick fix for overconstrained tables: if table have width attribute AND its value is less than sum
// of constrained columns widths plus minimal widths of uncostrained columns, then we'll expand the width of table
// to fit all columns
// 1. calculate sum of constrained column widths
// 2. calculate sum of unconstrained column minimal widths
$sum_cw = 0;
$sum_ucw = 0;
for ($i=0; $i < $columns; $i++) {
if ($table->is_constrained_column($i)) {
$sum_cw += $widths[$i];
} else {
$sum_ucw += $minwc[$i];
}
}
// 3. compare these widths with the table width and choose the maximal value
$width = max($width, $sum_cw + $sum_ucw);
// Second pass - disctribute the rest of the width
// Explanation of the stuff below (I've really had problems with this small piece of code, especially
// when I was trying to fix "bugs" inside it)
//
// First of all, no column can be narrower than it minimal width (determined by its content)
// Note that constrained columns have their widths distributed above, so we can exclude them for now
// (just throw them out and imagine that table does not contain any width-constrained cols)
//
// Second, the relative widths of columns will have _appoximately_ the same ratio as
// their maximal content widths. (In exception of cases where the first rule will take place -
// say for the table containing two columns with the VERY long text in the first and one or two words
// in the second)
//
// In general, this approach can be inoptimal in case of _very_ different font sizes
// inside the cells, of, say big images; nevertheless, it will give a good approximate
// AND still fast enough (unlike fully correct methods involving evaluation of the content height of the cell)
//
// Thus, we do the following:
// - calculate the ratio of current column MAXIMAL ($current_max) width to the sum of MAXIMAL widths of all columns left
// (inluding current) second rule applied. Note that we need remember about column spans and select
// maxw or maxwc in order.
// - then check if the rest of width will be too small for other columns to fit and decrease current columns
// width (see MIN function call)
// - then check again if our width will be too small for current column to fit (and expand if nesessary) -
// MAX function call
for ($i=0; $i < $columns; $i++) {
if (!$table->is_constrained_column($i)) {
// Get undistributed width (total table width - width of constrained columns)
$rest = $width - array_sum($widths);
// get max width of column being processed
// If width is equal to zero, use max constrained width, as this column could be covered by colspan;
// If not, we lose nothing, because all constrained columns are already processed earlier, and no more
// columns except these two types can have different constrained and raw widths
$current_max = max($maxw[$i], $maxwc[$i]);
// Get sum of maximal constrained widths of unplaced columns
$sum_max_cw = 0;
$sum_min_cw = 0;
for ($j=0; $j<$columns; $j++) {
if (!isset($widths[$j])) {
$sum_max_cw += max($maxw[$j], $maxwc[$j]);
$sum_min_cw += max($minw[$j], $minwc[$j]);
};
};
// If some unplaced columns have maximal (constrained width) greater zero
if ($sum_max_cw > 0) {
$current_max = min($current_max * $rest / $sum_max_cw, $rest - $sum_min_cw + max($minwc[$i], $minw[$i]));
};
// Check for minimal width (either unconstrained or constrained) of current column
$current_max = max($current_max, $minw[$i] == 0 ? $minwc[$i] : $minw[$i]);
// Store calculated width
$widths[$i] = $current_max;
}
}
// Process the case of a lone empty table cell (used, for example, for its background color)
// as we're using floating point numbers, we cannot use equals sign
if (array_sum($widths) < EPSILON) {
for ($i=0; $i<count($widths); $i++) {
$widths[$i] = 0.01;
};
};
// now - the last attempt; if total width is less than box width, then we have a situation when either
// all columns AND table are width constrained or the HTML similar to the following:
//
// <table cellpadding="0" width="100%" bgcolor="green"><tbody><tr>
// <td colspan="2" bgcolor="yellow"></td>
// <td style="width: 100px;" bgcolor="cyan">TEXT
//
// e.g. empty column (with zero width) and fixed-width column.
//
$wc = $table->getCSSProperty(CSS_WIDTH);
if (!$wc->isNull()) {
if (array_sum($widths) < $width) {
// Let's make zero-width columns
// non-zero width (so that they columd be expanded) and re-try expanding columns
//
for ($i=0; $i<count($widths); $i++) {
if ($widths[$i] == 0) { $widths[$i] = EPSILON; };
};
// Now, if there's at least one non-costrained columns, try expanding them again
$flags = $table->get_non_constrained_width_flags();
if (!any_flag_set($flags)) {
$flags = $table->get_non_constant_constrained_width_flags();
if (!any_flag_set($flags)) {
$flags = $table->get_non_image_constrained_width_flags();
if (!any_flag_set($flags)) {
for ($i=0; $i<count($flags); $i++) { $flags[$i] = true; };
};
};
};
$widths = expand_to_with_flags($width,
$widths,
$flags);
};
// in case of overconstrained table (e.g. two columns with 20% widths), expand them
$widths = expand_to($width, $widths);
};
$table->put_full_width(array_sum($widths));
// Now we need to sort array by key keeping key-value associations in order for array_slice to work correctly
ksort($widths, SORT_NUMERIC);
return $widths;
}
}
?>